Yersinia pestis is the bacterium that causes plague. It originated in Asia over 5,000 years ago and was responsible for three major pandemics: the Plague of Justinian in the 6th century, the Black Death in the 14th century, and a third pandemic from 1855-1959. Currently plague remains endemic in parts of Africa, Asia, and the Americas. Madagascar experiences regular outbreaks and had over 275 cases in 2015. Treatment with antibiotics is effective if administered promptly. Plague poses a potential bioterrorism risk if weaponized. Ongoing surveillance and public health responses are needed to combat future outbreaks.
Parasites are classified according to the International Code of Zoological Nomenclature and belong to a Phylum, Class, Order, Family, Genus, and Species. Parasite transmission can occur through soil, snails, arthropods, food/animals, contact, or air. The epidemiology of parasitic infections examines incidence, prevalence, intensity of infection, morbidity, and mortality.
This document provides information about endemic diseases. It defines endemic as the constant presence of a disease within a given population or geographic area without outside influence. Diseases are considered endemic when the basic reproduction rate and proportion of susceptible individuals allows transmission from one person to another on average. Examples of endemic diseases include various illnesses that are constantly present at specific locations around the world. Factors that influence a disease becoming endemic include the availability of hosts, pathogens, vectors, geographic location and climate.
This document discusses emerging and re-emerging infectious diseases. It begins by quoting Girolamo Frascatoro who spoke about syphilis in the 15th century, noting diseases will reoccur. Microbes evolve faster than humans. Infectious diseases have significantly impacted history, like the Black Plague. Emerging diseases are new, while re-emerging were previously controlled but increasing. Factors contributing to emergence include microbial adaptation, human behavior, and environmental changes. Examples discussed are MERS, Ebola, SARS, avian influenza, Zika virus, and potential bioterrorism agents. Preventing emergence requires surveillance, research, infrastructure, training, and prevention/control strategies.
This document discusses medical entomology and arthropod-borne diseases. It begins with an introduction to medical entomology and its importance. It then discusses different types of vectors that transmit pathogens and classifications of arthropods. Several sections provide details on major disease-transmitting arthropods like mosquitoes, sand flies, fleas, ticks and mites. It concludes with an overview of control measures for arthropods.
Genotyping of Human Lice Suggests MultipleEmergences of Body.docxbudbarber38650
Genotyping of Human Lice Suggests Multiple
Emergences of Body Lice from Local Head Louse
Populations
Wenjun Li1¤, Gabriel Ortiz1, Pierre-Edouard Fournier1, Gregory Gimenez1, David L. Reed2, Barry
Pittendrigh3, Didier Raoult1*
1 URMITE, UMR CNRS 6236, IRD 198, Université de la Méditerranée, Faculté de Médecine, Marseille, France, 2 Florida Museum of Natural History, Dickinson Hall, University
of Florida, Gainesville, Florida, United States of America, 3 Department of Entomology, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of
America
Abstract
Background: Genetic analyses of human lice have shown that the current taxonomic classification of head lice (Pediculus
humanus capitis) and body lice (Pediculus humanus humanus) does not reflect their phylogenetic organization. Three
phylotypes of head lice A, B and C exist but body lice have been observed only in phylotype A. Head and body lice have
different behaviours and only the latter have been involved in outbreaks of infectious diseases including epidemic typhus,
trench fever and louse borne recurrent fever. Recent studies suggest that body lice arose several times from head louse
populations.
Methods and Findings: By introducing a new genotyping technique, sequencing variable intergenic spacers which were
selected from louse genomic sequence, we were able to evaluate the genotypic distribution of 207 human lice. Sequence
variation of two intergenic spacers, S2 and S5, discriminated the 207 lice into 148 genotypes and sequence variation of
another two intergenic spacers, PM1 and PM2, discriminated 174 lice into 77 genotypes. Concatenation of the four
intergenic spacers discriminated a panel of 97 lice into 96 genotypes. These intergenic spacer sequence types were
relatively specific geographically, and enabled us to identify two clusters in France, one cluster in Central Africa (where a
large body louse outbreak has been observed) and one cluster in Russia. Interestingly, head and body lice were not
genetically differentiated.
Conclusions: We propose a hypothesis for the emergence of body lice, and suggest that humans with both low hygiene
and head louse infestations provide an opportunity for head louse variants, able to ingest a larger blood meal (a required
characteristic of body lice), to colonize clothing. If this hypothesis is ultimately supported, it would help to explain why poor
human hygiene often coincides with outbreaks of body lice. Additionally, if head lice act as a reservoir for body lice, and that
any social degradation in human populations may allow the formation of new populations of body lice, then head louse
populations are potentially a greater threat to humans than previously assumed.
Citation: Li W, Ortiz G, Fournier P-E, Gimenez G, Reed DL, et al. (2010) Genotyping of Human Lice Suggests Multiple Emergences of Body Lice from Local Head
Louse Populations. PLoS Negl Trop Dis 4(3): e641. doi:10.1371/journal.pntd.0000641
Editor: G.
This document reviews bacterial pathogens that have been isolated from bats. While many studies have investigated viruses in bats, less is known about pathogenic bacteria in bats and their impacts. Some common bacterial pathogens found in bats through traditional culture methods include Salmonella, Shigella, Yersinia, Clostridium, and Listeria. In particular, Salmonella Enteritidis and Salmonella Typhimurium which cause disease in humans and animals have been isolated from bats. The presence of these zoonotic bacterial pathogens in bats indicates bats could act as reservoirs and transmit diseases to humans and other animals. However, more research is still needed to understand the ecology and transmission cycles of bacterial pathogens involving bats.
This document discusses causes of parasitic disease in captive polar bears. Raw meat and fish fed to polar bears can contain parasites like Anisakiasis nematodes. Another common parasite is Baylisascaris, roundworms that infect the intestines of bears. While daily disinfecting reduces parasite infection rates, environmental contamination of eggs can still expose zoo animals and staff. Proper removal and disposal of polar bear waste is needed to control parasites.
Yersinia pestis is the bacterium that causes plague. It originated in Asia over 5,000 years ago and was responsible for three major pandemics: the Plague of Justinian in the 6th century, the Black Death in the 14th century, and a third pandemic from 1855-1959. Currently plague remains endemic in parts of Africa, Asia, and the Americas. Madagascar experiences regular outbreaks and had over 275 cases in 2015. Treatment with antibiotics is effective if administered promptly. Plague poses a potential bioterrorism risk if weaponized. Ongoing surveillance and public health responses are needed to combat future outbreaks.
Parasites are classified according to the International Code of Zoological Nomenclature and belong to a Phylum, Class, Order, Family, Genus, and Species. Parasite transmission can occur through soil, snails, arthropods, food/animals, contact, or air. The epidemiology of parasitic infections examines incidence, prevalence, intensity of infection, morbidity, and mortality.
This document provides information about endemic diseases. It defines endemic as the constant presence of a disease within a given population or geographic area without outside influence. Diseases are considered endemic when the basic reproduction rate and proportion of susceptible individuals allows transmission from one person to another on average. Examples of endemic diseases include various illnesses that are constantly present at specific locations around the world. Factors that influence a disease becoming endemic include the availability of hosts, pathogens, vectors, geographic location and climate.
This document discusses emerging and re-emerging infectious diseases. It begins by quoting Girolamo Frascatoro who spoke about syphilis in the 15th century, noting diseases will reoccur. Microbes evolve faster than humans. Infectious diseases have significantly impacted history, like the Black Plague. Emerging diseases are new, while re-emerging were previously controlled but increasing. Factors contributing to emergence include microbial adaptation, human behavior, and environmental changes. Examples discussed are MERS, Ebola, SARS, avian influenza, Zika virus, and potential bioterrorism agents. Preventing emergence requires surveillance, research, infrastructure, training, and prevention/control strategies.
This document discusses medical entomology and arthropod-borne diseases. It begins with an introduction to medical entomology and its importance. It then discusses different types of vectors that transmit pathogens and classifications of arthropods. Several sections provide details on major disease-transmitting arthropods like mosquitoes, sand flies, fleas, ticks and mites. It concludes with an overview of control measures for arthropods.
Genotyping of Human Lice Suggests MultipleEmergences of Body.docxbudbarber38650
Genotyping of Human Lice Suggests Multiple
Emergences of Body Lice from Local Head Louse
Populations
Wenjun Li1¤, Gabriel Ortiz1, Pierre-Edouard Fournier1, Gregory Gimenez1, David L. Reed2, Barry
Pittendrigh3, Didier Raoult1*
1 URMITE, UMR CNRS 6236, IRD 198, Université de la Méditerranée, Faculté de Médecine, Marseille, France, 2 Florida Museum of Natural History, Dickinson Hall, University
of Florida, Gainesville, Florida, United States of America, 3 Department of Entomology, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of
America
Abstract
Background: Genetic analyses of human lice have shown that the current taxonomic classification of head lice (Pediculus
humanus capitis) and body lice (Pediculus humanus humanus) does not reflect their phylogenetic organization. Three
phylotypes of head lice A, B and C exist but body lice have been observed only in phylotype A. Head and body lice have
different behaviours and only the latter have been involved in outbreaks of infectious diseases including epidemic typhus,
trench fever and louse borne recurrent fever. Recent studies suggest that body lice arose several times from head louse
populations.
Methods and Findings: By introducing a new genotyping technique, sequencing variable intergenic spacers which were
selected from louse genomic sequence, we were able to evaluate the genotypic distribution of 207 human lice. Sequence
variation of two intergenic spacers, S2 and S5, discriminated the 207 lice into 148 genotypes and sequence variation of
another two intergenic spacers, PM1 and PM2, discriminated 174 lice into 77 genotypes. Concatenation of the four
intergenic spacers discriminated a panel of 97 lice into 96 genotypes. These intergenic spacer sequence types were
relatively specific geographically, and enabled us to identify two clusters in France, one cluster in Central Africa (where a
large body louse outbreak has been observed) and one cluster in Russia. Interestingly, head and body lice were not
genetically differentiated.
Conclusions: We propose a hypothesis for the emergence of body lice, and suggest that humans with both low hygiene
and head louse infestations provide an opportunity for head louse variants, able to ingest a larger blood meal (a required
characteristic of body lice), to colonize clothing. If this hypothesis is ultimately supported, it would help to explain why poor
human hygiene often coincides with outbreaks of body lice. Additionally, if head lice act as a reservoir for body lice, and that
any social degradation in human populations may allow the formation of new populations of body lice, then head louse
populations are potentially a greater threat to humans than previously assumed.
Citation: Li W, Ortiz G, Fournier P-E, Gimenez G, Reed DL, et al. (2010) Genotyping of Human Lice Suggests Multiple Emergences of Body Lice from Local Head
Louse Populations. PLoS Negl Trop Dis 4(3): e641. doi:10.1371/journal.pntd.0000641
Editor: G.
This document reviews bacterial pathogens that have been isolated from bats. While many studies have investigated viruses in bats, less is known about pathogenic bacteria in bats and their impacts. Some common bacterial pathogens found in bats through traditional culture methods include Salmonella, Shigella, Yersinia, Clostridium, and Listeria. In particular, Salmonella Enteritidis and Salmonella Typhimurium which cause disease in humans and animals have been isolated from bats. The presence of these zoonotic bacterial pathogens in bats indicates bats could act as reservoirs and transmit diseases to humans and other animals. However, more research is still needed to understand the ecology and transmission cycles of bacterial pathogens involving bats.
This document discusses causes of parasitic disease in captive polar bears. Raw meat and fish fed to polar bears can contain parasites like Anisakiasis nematodes. Another common parasite is Baylisascaris, roundworms that infect the intestines of bears. While daily disinfecting reduces parasite infection rates, environmental contamination of eggs can still expose zoo animals and staff. Proper removal and disposal of polar bear waste is needed to control parasites.
The document reviews Swine Flu, including its history, structure, epidemiology, symptoms, diagnosis, treatment and prevention. It discusses how Swine Flu originated in Mexico in 2009. The virus is an influenza A virus with a single stranded RNA structure. Symptoms include fever, cough, sore throat and difficulty breathing. Treatment involves antiviral drugs like Tamiflu as well as rest, hydration and avoiding contact with infected individuals. Vaccines are also being developed to prevent the spread of the disease. The review concludes that further research is needed to better understand and control outbreaks of the Swine Flu virus.
The document discusses the origin and definition of entomology. It is the study of arthropods including insects, arachnids, crustaceans and others. Medical entomology focuses on arthropods that affect human and animal health, many acting as vectors that transmit pathogens. Examples of major vector groups are discussed like mosquitoes, flies, bugs, ticks and mites. Life cycles and modes of transmission of vector-borne diseases are described. The roles of arthropods as disease vectors and causes of injury are highlighted. Control methods for arthropods including environmental, chemical, biological and genetic approaches are briefly outlined.
Epidemiology is defined as the study of the distribution and determinants of health-related states in populations and the application of this study to control relevant problems. The aims of epidemiology are to describe disease distribution and magnitude, identify causal factors, and provide data to plan, implement, and evaluate prevention and treatment services. Epidemiology focuses on measuring mortality, morbidity, disability, and the distribution of disease characteristics in populations to understand disease causation and transmission dynamics within human, animal, and environmental reservoirs and the factors that influence susceptibility.
Tuberculosis: Why are we still fighting tb finalSHERIFFMUIDEEN1
This document discusses tuberculosis (TB), including its history, epidemiology, challenges, and a call to action for a TB-free UAE. It notes that TB has plagued humanity for thousands of years and remains a leading infectious killer. While diagnosis and treatment have improved, only about half of drug-resistant TB cases are cured. Obstacles to TB control include weak healthcare infrastructure, unregulated private care, lack of political will, and drug resistance. The document calls for intensifying TB awareness, screening, and treatment in the UAE to work towards eliminating the disease.
International Threats of Zoonotic Diseases - International Conference on One ...Tata Naipospos
The document summarizes an international conference presentation on zoonotic diseases and their threats. It notes that emerging zoonotic diseases pose an increasing global threat due to factors like population growth, increased animal production and trade, and human encroachment on wildlife habitats. An interdisciplinary "One Health" approach integrating human, animal, and environmental health is needed to monitor and control zoonotic diseases, which account for over 60% of all known human pathogens. Collaboration across medical, veterinary and policy sectors can help achieve efficiencies and early detection of outbreaks.
Zoonotic infections are diseases that can spread from animals to humans. Over 60% of infectious diseases in humans are zoonotic. Transmission can occur through direct contact with infected animals, indirect contact, vectors like ticks and mosquitoes, or contaminated food. Common zoonotic diseases include anthrax, bovine tuberculosis, salmonellosis, E. coli, rabies, avian influenza, and prion diseases. Bacteria, viruses, parasites, fungi, and prions can all cause zoonotic diseases. Proper hygiene and food handling can help prevent transmission of zoonotic infections.
The document discusses key concepts in epidemiology including descriptive and analytic epidemiology. Descriptive epidemiology examines the basic features of disease distribution in terms of time, place and person, while analytic epidemiology aims to identify causes and effects through quantitative analysis. The document also defines other epidemiological terms such as prevalence, incidence, risk, rate, ratio and their uses and calculations. Concepts like endemic, epidemic, pandemic are also explained along with examples.
This chapter discusses zoonotic and vector-borne diseases. It defines key terms like zoonotic, which refers to diseases that can be transmitted from animals to humans. Examples of transmission methods and diseases are provided, including malaria (transmitted by Anopheles mosquitoes), leishmaniasis (transmitted by sand flies), plague (transmitted by fleas from infected rodents), and Lyme disease (transmitted by blacklegged ticks). Control methods for vector-borne diseases include using insect repellents, draining standing water, and rodent control. Emerging diseases like Ebola, Zika virus, and hantavirus are also examined.
Although the helminth parasites of domestic hogs are well documented worldwide, no information is available about the digestive and pulmonary helminth infections of wild boar in Morocco. The lungs of 33 wild boars (Sus scrofa barbarus) (19 females and 14 males) from four area of El Hajeb province (Middle Atlas) hunted officially for wildlife damage control, from October 2014 to March 2015 were examined for lung nematodes. Twenty eight out of 33 wild baors, (84.4%) were positive for three species of Metastrongylus and their prevalence was as follows: Metastrongylus pudendotectus (84.4%), Metastrongylus confusus (72.7%) and Metastrongylus salmi (51.5%). In most cases, multi-species infection was observed. Prevalence and infection intensity were found greater in juvenile females less than 1 year old than in adults and males. Prevalence and intensity of infection were higher in wild boars collected from range lands and forest than in wild boars collected in the cultivate area. Further studies are needed to understand the factors structuring Metstrongylidae communites
This document provides an introduction and literature review on malaria. It discusses the background of malaria, the mosquito and Plasmodium species that cause malaria, and their modes of transmission. Key points include: malaria is caused by Plasmodium parasites transmitted via mosquito bites; the most common species are P. falciparum, P. vivax, P. malariae, P. ovale, and P. knowlesi; the parasite has a complex life cycle between mosquitoes and humans; transmission occurs when an infected mosquito bites and injects sporozoites into the bloodstream.
This document discusses bioterrorism response strategies. It defines bioterrorism as terrorism involving the intentional release of biological agents like bacteria, viruses, toxins, or other harmful materials. Biological agents can be spread through air, water, or food. The document outlines the history of bioterrorism and categorizes biological agents into three categories based on their ability to spread and cause harm. It identifies strategic planning as a key bioterrorism preparedness approach, including detection, laboratory analysis, response coordination, and education. Response strategies aim to limit the spread of communicable diseases through vaccination, treatment, quarantine, isolation, and movement restrictions.
This document discusses mosquitoes and the diseases they transmit. It covers several key points:
1. Mosquitoes transmit serious diseases like West Nile virus, eastern equine encephalitis, and heartworm in dogs.
2. The major mosquito-borne diseases in Georgia include West Nile virus, LaCrosse encephalitis, and eastern equine encephalitis.
3. Encephalitis is an inflammation of the brain that is caused by viral infections and has flu-like symptoms.
The document provides details on the transmission cycles and vectors of these diseases, as well as integrated mosquito management strategies like surveillance, source reduction, larviciding and adulticiding.
Prevalence of Intestinal Parasitic Infections among Patients Attended to Alri...CrimsonpublishersCJMI
Prevalence of Intestinal Parasitic Infections among Patients Attended to Alribat University hospital, Khartoum State, Sudan, 2017 by Mohammed HMN in Cohesive Journal of Microbiology & Infectious Disease
Impact of road networks on the distribution of dengue fever cases in Trinidad...rsmahabir
This study examined the impact of road networks on the distribution of dengue fever cases in Trinidad, West Indies. All confirmed cases of dengue hemorrhagic fever (DHF) observed during 1998 were georef- erenced and spatially located on a road map of Trinidad using Geographic Information Systems software. A new digital geographic layer representing these cases was created and the distances from these cases to the nearest classified road category (5 classifications based on a functional utility system) were examined. The distance from each spatially located DHF case to the nearest road in each of the 5 road subsets was determined and then subjected to an ANOVA and t-test to determine levels of association between minor road networks (especially 3rd and 4th class roads) and DHF cases and found DHF cases were located away from forests, especially 5th class roads). The frequency of DHF cases to different road classes was: 0% (1st class roads), 7% (2nd class roads), 32% (3rd class roads), 57% (4th class roads) and 4% (5th class road). The data clearly demonstrated that both class 3 and class 4 roads account for 89% of nearby dengue cases. These results represent the first evidence of dengue cases being found restricted between forested areas and major highways and would be useful when planning and implementing control strategies for dengue and Aedes aegypti mosquitoes.
This document discusses the social and economic impacts of HIV/AIDS in sub-Saharan Africa, with a focus on aging populations. It notes that early models underestimated the severity of the epidemic in Africa. HIV prevalence rates have changed who is most at risk over time. The AIDS pandemic threatens to overwhelm aging populations in sub-Saharan Africa as they need more support but have fewer able-bodied children to care for them due to the disease. The impacts of AIDS on older people could change dramatically as responses to the disease develop.
This document summarizes information about Tularemia, a bacterial zoonosis caused by Francisella tularensis. It discusses the history, etiology, epidemiology, life cycle, transmission, pathogenesis and symptoms of the disease. Tularemia is found globally and can infect a wide range of hosts. Humans typically get infected through arthropod bites, direct contact with infected animals, or inhalation. The disease presents with non-specific flu-like symptoms and can take several clinical forms depending on the route of infection.
Toxoplasma gondii is a parasite that infects around a third of the world's population. It can cause health issues in pregnant women and immunocompromised individuals. Some studies have found associations between T. gondii infection and changes in human behavior. This literature review will examine the parasite's ability to manipulate host behavior in rodents and humans, the potential mechanisms involved, and whether human manipulation could be adaptive for the parasite. It will also discuss diagnosis, treatment and prevention of toxoplasmosis.
Fibroid uterus a deep insight - by rxvichu ;)RxVichuZ
Hello friends...............................
This is my FIRST PPT OUTSIDE PHARM.D SYLLABUS!!!!
This ppt is REGARDING FIBROID UTERUS, with a therapeutical & pathophysiological approach!!
Do go through....will surely be useful for students posted in OBG departments!
Regards,
@rxvichu-alwz4uh! :)
Schizophrenia is a serious mental illness that affects how a person thinks, f...AmitSherawat2
Schizophrenia is a serious mental illness that affects how a person thinks, feels, and behaves. People with schizophrenia may seem like they have lost touch with reality, which can be distressing for them and for their family a
Mental status examination Maja (1) (1).pptxAmitSherawat2
The Mental Status Examination [MSE], also referred to as Mental State Examination, is an integral and essential skill to develop in a psychiatric evaluation. Conducting an accurate MSE helps elicit signs and symptoms of apparent mental illness and associated risk factors.
The Mental Status Examination [MSE], also referred to as Mental State Examination, is an integral and essential skill to develop in a psychiatric evaluation. Conducting an accurate MSE helps elicit signs and symptoms of apparent mental illness and associated risk factor
The document reviews Swine Flu, including its history, structure, epidemiology, symptoms, diagnosis, treatment and prevention. It discusses how Swine Flu originated in Mexico in 2009. The virus is an influenza A virus with a single stranded RNA structure. Symptoms include fever, cough, sore throat and difficulty breathing. Treatment involves antiviral drugs like Tamiflu as well as rest, hydration and avoiding contact with infected individuals. Vaccines are also being developed to prevent the spread of the disease. The review concludes that further research is needed to better understand and control outbreaks of the Swine Flu virus.
The document discusses the origin and definition of entomology. It is the study of arthropods including insects, arachnids, crustaceans and others. Medical entomology focuses on arthropods that affect human and animal health, many acting as vectors that transmit pathogens. Examples of major vector groups are discussed like mosquitoes, flies, bugs, ticks and mites. Life cycles and modes of transmission of vector-borne diseases are described. The roles of arthropods as disease vectors and causes of injury are highlighted. Control methods for arthropods including environmental, chemical, biological and genetic approaches are briefly outlined.
Epidemiology is defined as the study of the distribution and determinants of health-related states in populations and the application of this study to control relevant problems. The aims of epidemiology are to describe disease distribution and magnitude, identify causal factors, and provide data to plan, implement, and evaluate prevention and treatment services. Epidemiology focuses on measuring mortality, morbidity, disability, and the distribution of disease characteristics in populations to understand disease causation and transmission dynamics within human, animal, and environmental reservoirs and the factors that influence susceptibility.
Tuberculosis: Why are we still fighting tb finalSHERIFFMUIDEEN1
This document discusses tuberculosis (TB), including its history, epidemiology, challenges, and a call to action for a TB-free UAE. It notes that TB has plagued humanity for thousands of years and remains a leading infectious killer. While diagnosis and treatment have improved, only about half of drug-resistant TB cases are cured. Obstacles to TB control include weak healthcare infrastructure, unregulated private care, lack of political will, and drug resistance. The document calls for intensifying TB awareness, screening, and treatment in the UAE to work towards eliminating the disease.
International Threats of Zoonotic Diseases - International Conference on One ...Tata Naipospos
The document summarizes an international conference presentation on zoonotic diseases and their threats. It notes that emerging zoonotic diseases pose an increasing global threat due to factors like population growth, increased animal production and trade, and human encroachment on wildlife habitats. An interdisciplinary "One Health" approach integrating human, animal, and environmental health is needed to monitor and control zoonotic diseases, which account for over 60% of all known human pathogens. Collaboration across medical, veterinary and policy sectors can help achieve efficiencies and early detection of outbreaks.
Zoonotic infections are diseases that can spread from animals to humans. Over 60% of infectious diseases in humans are zoonotic. Transmission can occur through direct contact with infected animals, indirect contact, vectors like ticks and mosquitoes, or contaminated food. Common zoonotic diseases include anthrax, bovine tuberculosis, salmonellosis, E. coli, rabies, avian influenza, and prion diseases. Bacteria, viruses, parasites, fungi, and prions can all cause zoonotic diseases. Proper hygiene and food handling can help prevent transmission of zoonotic infections.
The document discusses key concepts in epidemiology including descriptive and analytic epidemiology. Descriptive epidemiology examines the basic features of disease distribution in terms of time, place and person, while analytic epidemiology aims to identify causes and effects through quantitative analysis. The document also defines other epidemiological terms such as prevalence, incidence, risk, rate, ratio and their uses and calculations. Concepts like endemic, epidemic, pandemic are also explained along with examples.
This chapter discusses zoonotic and vector-borne diseases. It defines key terms like zoonotic, which refers to diseases that can be transmitted from animals to humans. Examples of transmission methods and diseases are provided, including malaria (transmitted by Anopheles mosquitoes), leishmaniasis (transmitted by sand flies), plague (transmitted by fleas from infected rodents), and Lyme disease (transmitted by blacklegged ticks). Control methods for vector-borne diseases include using insect repellents, draining standing water, and rodent control. Emerging diseases like Ebola, Zika virus, and hantavirus are also examined.
Although the helminth parasites of domestic hogs are well documented worldwide, no information is available about the digestive and pulmonary helminth infections of wild boar in Morocco. The lungs of 33 wild boars (Sus scrofa barbarus) (19 females and 14 males) from four area of El Hajeb province (Middle Atlas) hunted officially for wildlife damage control, from October 2014 to March 2015 were examined for lung nematodes. Twenty eight out of 33 wild baors, (84.4%) were positive for three species of Metastrongylus and their prevalence was as follows: Metastrongylus pudendotectus (84.4%), Metastrongylus confusus (72.7%) and Metastrongylus salmi (51.5%). In most cases, multi-species infection was observed. Prevalence and infection intensity were found greater in juvenile females less than 1 year old than in adults and males. Prevalence and intensity of infection were higher in wild boars collected from range lands and forest than in wild boars collected in the cultivate area. Further studies are needed to understand the factors structuring Metstrongylidae communites
This document provides an introduction and literature review on malaria. It discusses the background of malaria, the mosquito and Plasmodium species that cause malaria, and their modes of transmission. Key points include: malaria is caused by Plasmodium parasites transmitted via mosquito bites; the most common species are P. falciparum, P. vivax, P. malariae, P. ovale, and P. knowlesi; the parasite has a complex life cycle between mosquitoes and humans; transmission occurs when an infected mosquito bites and injects sporozoites into the bloodstream.
This document discusses bioterrorism response strategies. It defines bioterrorism as terrorism involving the intentional release of biological agents like bacteria, viruses, toxins, or other harmful materials. Biological agents can be spread through air, water, or food. The document outlines the history of bioterrorism and categorizes biological agents into three categories based on their ability to spread and cause harm. It identifies strategic planning as a key bioterrorism preparedness approach, including detection, laboratory analysis, response coordination, and education. Response strategies aim to limit the spread of communicable diseases through vaccination, treatment, quarantine, isolation, and movement restrictions.
This document discusses mosquitoes and the diseases they transmit. It covers several key points:
1. Mosquitoes transmit serious diseases like West Nile virus, eastern equine encephalitis, and heartworm in dogs.
2. The major mosquito-borne diseases in Georgia include West Nile virus, LaCrosse encephalitis, and eastern equine encephalitis.
3. Encephalitis is an inflammation of the brain that is caused by viral infections and has flu-like symptoms.
The document provides details on the transmission cycles and vectors of these diseases, as well as integrated mosquito management strategies like surveillance, source reduction, larviciding and adulticiding.
Prevalence of Intestinal Parasitic Infections among Patients Attended to Alri...CrimsonpublishersCJMI
Prevalence of Intestinal Parasitic Infections among Patients Attended to Alribat University hospital, Khartoum State, Sudan, 2017 by Mohammed HMN in Cohesive Journal of Microbiology & Infectious Disease
Impact of road networks on the distribution of dengue fever cases in Trinidad...rsmahabir
This study examined the impact of road networks on the distribution of dengue fever cases in Trinidad, West Indies. All confirmed cases of dengue hemorrhagic fever (DHF) observed during 1998 were georef- erenced and spatially located on a road map of Trinidad using Geographic Information Systems software. A new digital geographic layer representing these cases was created and the distances from these cases to the nearest classified road category (5 classifications based on a functional utility system) were examined. The distance from each spatially located DHF case to the nearest road in each of the 5 road subsets was determined and then subjected to an ANOVA and t-test to determine levels of association between minor road networks (especially 3rd and 4th class roads) and DHF cases and found DHF cases were located away from forests, especially 5th class roads). The frequency of DHF cases to different road classes was: 0% (1st class roads), 7% (2nd class roads), 32% (3rd class roads), 57% (4th class roads) and 4% (5th class road). The data clearly demonstrated that both class 3 and class 4 roads account for 89% of nearby dengue cases. These results represent the first evidence of dengue cases being found restricted between forested areas and major highways and would be useful when planning and implementing control strategies for dengue and Aedes aegypti mosquitoes.
This document discusses the social and economic impacts of HIV/AIDS in sub-Saharan Africa, with a focus on aging populations. It notes that early models underestimated the severity of the epidemic in Africa. HIV prevalence rates have changed who is most at risk over time. The AIDS pandemic threatens to overwhelm aging populations in sub-Saharan Africa as they need more support but have fewer able-bodied children to care for them due to the disease. The impacts of AIDS on older people could change dramatically as responses to the disease develop.
This document summarizes information about Tularemia, a bacterial zoonosis caused by Francisella tularensis. It discusses the history, etiology, epidemiology, life cycle, transmission, pathogenesis and symptoms of the disease. Tularemia is found globally and can infect a wide range of hosts. Humans typically get infected through arthropod bites, direct contact with infected animals, or inhalation. The disease presents with non-specific flu-like symptoms and can take several clinical forms depending on the route of infection.
Toxoplasma gondii is a parasite that infects around a third of the world's population. It can cause health issues in pregnant women and immunocompromised individuals. Some studies have found associations between T. gondii infection and changes in human behavior. This literature review will examine the parasite's ability to manipulate host behavior in rodents and humans, the potential mechanisms involved, and whether human manipulation could be adaptive for the parasite. It will also discuss diagnosis, treatment and prevention of toxoplasmosis.
Fibroid uterus a deep insight - by rxvichu ;)RxVichuZ
Hello friends...............................
This is my FIRST PPT OUTSIDE PHARM.D SYLLABUS!!!!
This ppt is REGARDING FIBROID UTERUS, with a therapeutical & pathophysiological approach!!
Do go through....will surely be useful for students posted in OBG departments!
Regards,
@rxvichu-alwz4uh! :)
Similar a African Trypanosomiasis Matthew Malone 3-9-2012.pptx (18)
Schizophrenia is a serious mental illness that affects how a person thinks, f...AmitSherawat2
Schizophrenia is a serious mental illness that affects how a person thinks, feels, and behaves. People with schizophrenia may seem like they have lost touch with reality, which can be distressing for them and for their family a
Mental status examination Maja (1) (1).pptxAmitSherawat2
The Mental Status Examination [MSE], also referred to as Mental State Examination, is an integral and essential skill to develop in a psychiatric evaluation. Conducting an accurate MSE helps elicit signs and symptoms of apparent mental illness and associated risk factors.
The Mental Status Examination [MSE], also referred to as Mental State Examination, is an integral and essential skill to develop in a psychiatric evaluation. Conducting an accurate MSE helps elicit signs and symptoms of apparent mental illness and associated risk factor
Presentations are typically demonstrations, introduction, lecture, or speech meant to inform, persuade, inspire, motivate, build goodwill, or present a new idea/product. Presentations usually require preparation, organization, event planning, writing, use of visual aids, dealing with stress, and answering questions.
The immune system is a complex network of organs, cells and proteins that def...AmitSherawat2
The immune system is a complex network of organs, cells and proteins that defends the body against infection, whilst protecting the body's own cells. The immune system keeps a record of every germ (microbe) it has ever defeated so it can recognise and destroy the microbe quickly if it enters the body again.
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How do you get rid of ulcers on your legs?
occlusive (air- and water-tight) dressings – ulcers heal better when they are covered. These dressings should be changed weekly. compression treatment – boosts internal pressure, using either elasticised bandages or stockings. This is particularly effective if multiple layers are used.
Leveraging Generative AI to Drive Nonprofit InnovationTechSoup
In this webinar, participants learned how to utilize Generative AI to streamline operations and elevate member engagement. Amazon Web Service experts provided a customer specific use cases and dived into low/no-code tools that are quick and easy to deploy through Amazon Web Service (AWS.)
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This is part 1 of my Java Learning Journey. This Contains Custom methods, classes, constructors, packages, multithreading , try- catch block, finally block and more.
A workshop hosted by the South African Journal of Science aimed at postgraduate students and early career researchers with little or no experience in writing and publishing journal articles.
A review of the growth of the Israel Genealogy Research Association Database Collection for the last 12 months. Our collection is now passed the 3 million mark and still growing. See which archives have contributed the most. See the different types of records we have, and which years have had records added. You can also see what we have for the future.
Walmart Business+ and Spark Good for Nonprofits.pdfTechSoup
"Learn about all the ways Walmart supports nonprofit organizations.
You will hear from Liz Willett, the Head of Nonprofits, and hear about what Walmart is doing to help nonprofits, including Walmart Business and Spark Good. Walmart Business+ is a new offer for nonprofits that offers discounts and also streamlines nonprofits order and expense tracking, saving time and money.
The webinar may also give some examples on how nonprofits can best leverage Walmart Business+.
The event will cover the following::
Walmart Business + (https://business.walmart.com/plus) is a new shopping experience for nonprofits, schools, and local business customers that connects an exclusive online shopping experience to stores. Benefits include free delivery and shipping, a 'Spend Analytics” feature, special discounts, deals and tax-exempt shopping.
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Chapter wise All Notes of First year Basic Civil Engineering.pptxDenish Jangid
Chapter wise All Notes of First year Basic Civil Engineering
Syllabus
Chapter-1
Introduction to objective, scope and outcome the subject
Chapter 2
Introduction: Scope and Specialization of Civil Engineering, Role of civil Engineer in Society, Impact of infrastructural development on economy of country.
Chapter 3
Surveying: Object Principles & Types of Surveying; Site Plans, Plans & Maps; Scales & Unit of different Measurements.
Linear Measurements: Instruments used. Linear Measurement by Tape, Ranging out Survey Lines and overcoming Obstructions; Measurements on sloping ground; Tape corrections, conventional symbols. Angular Measurements: Instruments used; Introduction to Compass Surveying, Bearings and Longitude & Latitude of a Line, Introduction to total station.
Levelling: Instrument used Object of levelling, Methods of levelling in brief, and Contour maps.
Chapter 4
Buildings: Selection of site for Buildings, Layout of Building Plan, Types of buildings, Plinth area, carpet area, floor space index, Introduction to building byelaws, concept of sun light & ventilation. Components of Buildings & their functions, Basic concept of R.C.C., Introduction to types of foundation
Chapter 5
Transportation: Introduction to Transportation Engineering; Traffic and Road Safety: Types and Characteristics of Various Modes of Transportation; Various Road Traffic Signs, Causes of Accidents and Road Safety Measures.
Chapter 6
Environmental Engineering: Environmental Pollution, Environmental Acts and Regulations, Functional Concepts of Ecology, Basics of Species, Biodiversity, Ecosystem, Hydrological Cycle; Chemical Cycles: Carbon, Nitrogen & Phosphorus; Energy Flow in Ecosystems.
Water Pollution: Water Quality standards, Introduction to Treatment & Disposal of Waste Water. Reuse and Saving of Water, Rain Water Harvesting. Solid Waste Management: Classification of Solid Waste, Collection, Transportation and Disposal of Solid. Recycling of Solid Waste: Energy Recovery, Sanitary Landfill, On-Site Sanitation. Air & Noise Pollution: Primary and Secondary air pollutants, Harmful effects of Air Pollution, Control of Air Pollution. . Noise Pollution Harmful Effects of noise pollution, control of noise pollution, Global warming & Climate Change, Ozone depletion, Greenhouse effect
Text Books:
1. Palancharmy, Basic Civil Engineering, McGraw Hill publishers.
2. Satheesh Gopi, Basic Civil Engineering, Pearson Publishers.
3. Ketki Rangwala Dalal, Essentials of Civil Engineering, Charotar Publishing House.
4. BCP, Surveying volume 1
বাংলাদেশের অর্থনৈতিক সমীক্ষা ২০২৪ [Bangladesh Economic Review 2024 Bangla.pdf] কম্পিউটার , ট্যাব ও স্মার্ট ফোন ভার্সন সহ সম্পূর্ণ বাংলা ই-বুক বা pdf বই " সুচিপত্র ...বুকমার্ক মেনু 🔖 ও হাইপার লিংক মেনু 📝👆 যুক্ত ..
আমাদের সবার জন্য খুব খুব গুরুত্বপূর্ণ একটি বই ..বিসিএস, ব্যাংক, ইউনিভার্সিটি ভর্তি ও যে কোন প্রতিযোগিতা মূলক পরীক্ষার জন্য এর খুব ইম্পরট্যান্ট একটি বিষয় ...তাছাড়া বাংলাদেশের সাম্প্রতিক যে কোন ডাটা বা তথ্য এই বইতে পাবেন ...
তাই একজন নাগরিক হিসাবে এই তথ্য গুলো আপনার জানা প্রয়োজন ...।
বিসিএস ও ব্যাংক এর লিখিত পরীক্ষা ...+এছাড়া মাধ্যমিক ও উচ্চমাধ্যমিকের স্টুডেন্টদের জন্য অনেক কাজে আসবে ...
3. Learning Goals
• Understand the causes, risk factors, and modes of transmission
for Human African Trypanosomiasis (HAT)
• Know the role of armed conflict in the rise of infection rates
throughout Africa
• Use past HAT outbreak patterns and causes to understand the
implications for future infection
4. The Problem
• Multiple HAT outbreaks have occurred over the last century.
• Armed conflict in Africa has escalated disease rates in recent
years.
• Continued displacement of populations may cause many more
outbreaks.
• Displacement widens the geographic disease spread.
5. Causal Agents
• Caused by the protozoan
Trypanosoma Brucei
• Has three subspecies:
– Trypanosoma brucei
gambiense
– Trypanosoma brucei
rhodesiense
– Trypanosoma brucei
brucei (animals only)
6. Vector Biology
• The vector for HAT is the
tsetse fly
• Biological Vector
• Inhabits rural areas
• Bites during daytime hours
• Both males and females are
capable of carrying and
transmitting the disease.
7. Vector Biology Cont’d
• Tsetse flies belong to the
genus Glossina
• Glossina contains 3
subgroups
– Glossina (includes G.
morsitans group)
– Nemorhina (includes G.
palpalis group)
– Austenina (includes G.
fusca group)
8. Vector Biology Cont’d
• Vectors of T.b.
gambiense
– G. palpalis & G.
tachinoides groups
• Vectors of T.b.
rhodesiense
– G. morsitans, G.
swynnertoni, & G.
pallidipes groups
11. Risk Factors
• Civil Disturbance/War
• Cattle Movements
• Population
Movements/Migrations
(Refugees)
• Reduced Health
Program Financing
• Rural Living
Environment
12. Case Study: Uganda HAT Outbreak
• Began in the late 1980s and
persisted through 2005
• Refugees migrated from
Uganda to Zaire and
Sudanacquired infection
• Refugees migrated back to
Uganda accompanied by
infected Sudanese
refugeesspread infection
13. Case Study Cont’d
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14. Epidemiology
• In 1986, it was estimated
that approx. 70 million
people lived in areas
conducive to disease
transmission
• HAT affects 36 countries in
sub-Saharan Africa
• According to the World
Health Organization, HAT
causes ~40,000 deaths in
Africa annually
15. Epidemiology Cont’d
• The total amount of reported HAT cases has
decreased substantially over time.
• 1998: ~40,000 reported cases; >250,000 actual
cases
• 2004: ~18,000 reported cases; between 50,000 and
70,000 actual cases
• 2010: ~7,000 reported cases; ~30,000 actual cases
• Cases involving T.b. rhodesiense are much rarer
than those involving T.b. gambiense.
17. Geographical Distribution
• 1998- World Health Organization states that there are over 200
active foci of HAT between latitude 15 degrees north and 15
degrees south (“tsetse belt”).
• T.b. gambiense is mostly found in western and central Africa.
– Over 95% of the cases of human infection found in the
Democratic Republic of Congo, Angola, Sudan, Central
African Republic, Chad, and northern Uganda.
• T.b. rhodesiense is found mostly in eastern and southern
Africa.
– Over 95% of the cases of human infection occur in
Tanzania, Uganda, Malawi, and Zambia.
19. Geographical Distribution/Conflict
• The resurgence of HAT in several countries has been
attributed to conflict and/or war.
• Cases of HAT have been seen to occur significantly
more often in countries where there is conflict,
internationalized civil war, and/or high political terror.
21. Geographical Distribution/Conflict Cont’d
• Forced population movement
increases transmission.
• Migration causes
trypanosomes to circulate
from high-incidence to low-
incidence areas.
• Conflict causes breakdown of
control measures and
surveillance, increasing
disease spread
22. References
1. Pepin J., Meda H. The epidemiology and control of human African
trypanosomiasis. Adv Parasitol, 49 (2001), pp. 71–132
2. Human African trypanosomiasis (sleeping sickness). Available at
http://www.who.int/mediacentre/factsheets/fs259/en/. Accessed March 8, 2012.
3. Smith D., Pepin J., Stich A. Human African trypanosomiasis: an emerging public
health crisis. Br Med Bull, 54 (1998), pp. 341–355
4. Brun R., Blum J., Chappuis F., Burri C. Human African trypanosomiasis. Lancet
(2009), pp. 148–159
5. Simarro P., Jannin J., Cattand P. Eliminating human African trypanosomiasis:
where do we stand and what comes next? PLoS Med. 5, e55 (2008), pp. 174–180
23. References Cont’d
6. Parasites- African Trypanosomiasis (also known as Sleeping Sickness). Available
at http://www.cdc.gov/parasites/sleepingsickness/. Accessed March 8, 2012.
7. Berrang-Ford L, Martin O, Maiso F, Waltner-Toews D, McDermott J (2006)
Sleeping sickness in Uganda: revisiting current and historical distributions. Afr
Health Sci 6: 223–231
8. Kuzoe FAS. (1993) Current situation of African trypanosomiasis. Acta Trop. 54:
153-162
9. MacGregor P., Matthews K. New discoveries in the transmission biology of
sleeping sickness parasites: applying the basics. J. Mol. Med., 88 (2010), pp. 865–
871
There have been three major HAT epidemics in Africa over the past 100 years. The first epidemic, which took place between 1896 and 1906, largely affected equatorial Africa and caused the death of approximately 800,000 people.4 The second epidemic took place between 1920 and 1940 and caused colonial powers to invest in control and surveillance programs that almost eradicated the disease by the 1960s.4 The third epidemic, which occurred in 1970, was a direct result of the civil conflicts and the breakdown of HAT control and surveillance activities that took place after the advent of independence in most countries where HAT was endemic.4,5 This epidemic saw its peak in the late 1990s.
Social upheavals, population movements, and wars, combined with lack of awareness and poverty, have caused the disease to spread and evolve across sub-Saharan Africa. These risk factors still exist today, and for this reason, future epidemics are still very possible. In order to prevent future epidemics, steps must be taken to eliminate these factors or, at least, greatly minimize them.
Human African Trypanosomiasis is caused by Trypanosoma Brucei which is a protozoan. It has three different subspecies which are Trypanosoma brucei gambiense (95% of all infections), Trypanosoma brucei rhodesiense, and Trypanosoma brucei brucei (under normal conditions does not infect humans). Trypanosoma brucei gambiense is usually associated with the chronic form of the disease and Trypanosoma brucei rhodesiense is usually associated with the acute form of the disease. T.b. rhodesiense is more virulent than T.b. gambiense and is less prone to cause large epidemics.1 This observation has been validated by the fact that there have been much less outbreaks caused by T.b. rhodesiense over time than outbreaks caused by T.b. gambiense.
Picture: Trypanosoma Brucei
Source: http://www.humenhealth.com/trypanosoma-brucei
The vector for HAT is the tsetse fly. Although the tsetse fly is a biological vector, mechanical transmission through other blood-sucking insects is possible.2 There is less epidemiological data concerning this type of transmission. The flies only bite during daytime hours, and both male and female flies are capable of carrying and transmitting the disease.6 In eastern Africa the flies inhabit woodland areas and thickets throughout the savannah, and in western Africa the flies inhabit forests and vegetation along streams.6 Tsetse flies are the main means of transmission for HAT. However, mother to child infection has been seen as trypanosomes can cross the placenta and infect the fetus.6 Reports of accidental contamination via pricks from contaminated needles have also been reported.6
Pic: Tsetse fly
Source: http://fohn.net/pictures-of-flies/pix-flies-6.html
Tsetse flies all belong to the genus Glossina. This genus consists of three subgroubs: Glossina (includes G. morsitans group), Nemorhina (includes G. palpalis group), Austenina (includes G. fusca group).1 For a species of Glossina, its vectorial capacity is determined by two factors.
Pic: Tsetse fly
Source: http://www.vectorbase.org/Glossina_morsitans/Info/Index
For a species of Glossina, its vectorial capacity is determined by two factors. These factors are the ability to become infected while feeding on a vertebrate host, and the ability to subsequently support the development of the infection and transmit trypanosomes to a different vertebrate host.1 Following these criteria, the G. palpalis group and the G. morsitans group are the only groups that contain species and subspecies that are vectors of T.b.gambiense.1 G. palpalis palpalis in forest areas and G. palpalis gambiensis in savannah areas (both are species of the G. palpalis group) are very proficient vectors species of T.b. gambiense in West and Central Africa.1 The vectors of T.b. rhodesiense are different from those of T.b gambiense. This strain is mostly transmitted by G.m. morsitans and G.m. centralis in East Africa (except Uganda and Kenya), G. pallidipes in eastern and southern Africa, and G. swynnertoni in Kenya and Tanzania.1 These species are all savannah species of the G. morsitans group.
Pic: Species and Subspecies of Glossina that are vectors for T.b. gambiense and T.b. rhodesiense
Source: Pepin J., Meda H. The epidemiology and control of human African trypanosomiasis. Adv Parasitol, 49 (2001), pp. 71–132
For T.b. gambiense, the main reservoir of infection is humans, although both wild and domestic animals have also been seen to harbor the infection. For T.b. rhodesiense, the main reservoir for infection is cattle. However, other domestic animals (dogs, pigs, and sheep) and many game animals (warthogs, bushbuck, hartebeest, lions, zebras, impala, waterbuck, and hyenas) also carry the infection.1
Left Pic: People Walking
Source: http://www.worldofstock.com/stock-photos/crowd-of-people-walking-on-a-sidewalk/TAJ1292
Right Pic: Cattle
Source: http://photo-dictionary.com/phrase/564/cattle.html#b
Pic: HAT Transmission Cycle
Source: Simarro P., Jannin J., Cattand P. Eliminating human African trypanosomiasis: where do we stand and what comes next? PLoS Med. 5, e55 (2008), pp. 174–180
Tsetse flies are only found in sub-Saharan Africa. Within sub-Saharan Africa, there are multiple different risk factors that make some populations much more susceptible to acquiring HAT than others. Populations living in rural areas are the most at risk for becoming infected, as these areas are where tsetse flies are mostly found.2 Within rural areas, the populations most at risk for becoming infected are those that depend on agriculture, animal husbandry, fishing, or hunting.2 These activities heighten the exposure of those populations to tsetse flies and increases the probability that they will be bitten and contract HAT.
HAT was very nearly eradicated in many Sub-Saharan countries around the 1960s, but in recent years, as mentioned in the background, there has been a resurgence of HAT cases in several countries. There are several factors that contribute to both HAT resurgence and the onset of epidemics. These factors include civil disturbance, war, reduced health financing, dismantling of disease control programs, cattle movements, and population movements/migration (includes refugees).3 Population movement are especially significant in the transmission and spread of the disease because when large groups of people migrate from one area to another, trypanosomes are circulated from high-incidence to low-incidence areas, causing more susceptible populations to be at increased risk of acquiring infection.1
Pic: Central African Soldiers
Source: http://www.usatoday.com/news/opinion/forum/story/2011-10-18/lra-resistance-army-uganda/50816576/1
A case study that exemplifies the impact of migrations on disease spread and the onset of epidemics is the recent outbreak of HAT that has been observed in northwestern Uganda. This outbreak began in the late 1980s and persisted through 2005.7 Refugees migrated from Uganda to Zaire and Sudan, where they acquired infection. Years later, these refugees migrated back to Uganda accompanied by infected Sudanese refugees.1
Pic: African Refugees
Source: http://refugeechild.mkfc.se/2009/02/un-congo-refugees-escaping-in-many-directions/
Pic: Sleeping Sickness in south-eastern Uganda, 1905-2001
Source: Berrang-Ford L, Martin O, Maiso F, Waltner-Toews D, McDermott J (2006) Sleeping sickness in Uganda: revisiting current and historical distributions. Afr Health Sci 6: 223–231
HAT occurs in 36 sub-Saharan African countries where over 50 million people are at risk for becoming infected.8 Currently, it is estimated that over 50,000 people within these countries are actually infected.9 HAT has been the leading cause of mortality in many different villages in the Democratic Republic of Congo, Angola, and Southern Sudan during epidemic periods.2 During these periods, the prevalence of HAT reached 50% and the disease caused more deaths than HIV/AIDS.2
Top Pic: Trypanosoma brucei gambiense
Source: http://158.83.1.40/Buckelew/Trypanosoma%20brucei%20gambiense.htm
Bottom Pic: Trypanosoma brucei rhodesiense
Source: http://tolweb.org/Trypanosoma/98034
The estimated amount of cases of HAT in Africa has changed drastically over time due to the escalation and cessation of epidemics. Between 1998 and 2004, the total amount of reported HAT cases, including both strains of the disease, fell from approximately 37,991 to 17,616, and the estimated number of actual cases was between 50,000 and 70,000.2 In 2009, the number of reported cases had dropped to 9,878. 2 This marked the first time in five decades that the number of reported cases had fallen below 10,000. In 2010, 7,139 cases were reported, and the current estimated number of actual cases is 30,000. 2
Exact numbers for the amount of cases of the disease are hard to acquire due to the large amount of underreporting that occurs. For example, in 1998, almost 40,000 cases were reported but reports suggested that there might have been around 300,000 undiagnosed cases.2 In addition, there is more epidemiological data available for HAT caused by T.b. gambiense than for HAT caused by T.b. rhodesiense since HAT caused by T.b. rhodesiense is much rarer.
Pic: Trypanosoma brucei gambiense comparison between population placed under active surveillance and new cases
Source: Brun R., Blum J., Chappuis F., Burri C. Human African trypanosomiasis. Lancet (2009), pp. 148–159
T.b. rhodesiense is sometimes referred to as East African sleeping sickness because it is found mostly in eastern and southern Africa. Over 95% of the cases of human infection occur in Tanzania, Uganda, Malawi, and Zambia.6 T.b. gambiense is sometimes referred to as West African sleeping sickness because it is mostly found in western and central Africa. Over 95% of the cases of human infection are found in the Democratic Republic of Congo, Angola, Sudan, Central African Republic, Chad, and northern Uganda.6 Both forms of the disease have been major causes of depopulation of large tracts of fertile land in Africa.8 In 1998, the World Health Organization stated that there were over 200 active foci of HAT that were located between latitude 15 degrees north and 15 degrees south.1
According to a 2001 research article, Uganda was the only country where both T.b. gambiense and T.b. rhodesiense could be found without any overlap.1 This same article stated that the Democratic Republic of Congo was the country with the most severe HAT epidemic and that Angola was the country with the second highest amount of HAT cases. These observations are still seen today, although the number of HAT cases has declined a considerable amount over time. In 2010, the Democratic Republic of Congo was the only country in Africa to report over 500 new cases annually.2 Angola, Chad, Sudan, Central African Republic, and Uganda have all declared between 100 and 500 new cases annually.2 Cameroon, Congo, the Ivory Coast, Guinea, Malawi, United Republic of Tanzania, Gabon, Nigeria, Zambia, and Zimbabwe have been reporting less than 100 cases annually.2 Benin, Botswana, Burkina Faso, Burundi, Ethiopia, Gambia, Ghana, Guinea Bissau, Kenya, Liberia, Mali, Mozambique, Namibia, Niger, Rwanda, Senegal, Sierra Leone, Swaziland, and Togo have reported no new cases in over 10 years.2
Pic: Map of Africa Showing the Epidemiological Status of Countries Considered Endemic for the Disease
Source: Simarro P., Jannin J., Cattand P. Eliminating human African trypanosomiasis: where do we stand and what comes next? PLoS Med. 5, e55 (2008), pp. 174–180
The resurgence of HAT in several countries has been attributed to conflict and/or war. Conflict has also caused HAT cases to keep arising in regions that have low resources and in regions that are politically unstable.10 Cases of HAT have been seen to occur significantly more often in countries when there is conflict, internationalized civil war, and/or high political terror.10
Pic: HAT incidence by conflict severity (a) and political terror scale (b)
Source: Berrang-Ford L., Breau L. Conflict and human trypanosomiasis. Soc. Sci. Med. (2010), pp. 398–407
The fact that many conflicts still exist in Africa today is a cause for concern because these conflicts can potentially cause more outbreaks of HAT by putting reservoirs for infection in more contact with disease vectors. Conflict has been shown to cause problems for countries’ disease surveillance and control programs, and as long as conflict still exists, another HAT epidemic is very possible .
Pic: African Soldiers Attacking Protesters
Source: http://www.telegraph.co.uk/news/worldnews/africaandindianocean/guinea/6240759/Guinea-soldiers-shoot-dead-dozens-of-protesters.html