Everything all about dengue.

1. IMF - Kyrgyztan
SUBMITTED BY:
Ravi Abarnaa
14A
2016 BATCH

3. CONTENTS
 Introduction
 Dengue virus
 Epidemiology
 Etiology
 Pathophysiology
 Classification
 Clinical presentation
 Diagnosis
 Complications
 Management
 Prevention
 Vaccines

4. INTRODUCTION
• Dengue fever is an acute infectious viral disease, also known as
breakbone fever
• Dengue is transmitted by mosquitoes of the genus.
• Dengue hemorrhagic fever is a fatal manifestation of dengue
virus that manifest with bleeding diathesis and hypovolemic
shock.

5. DENGUE VIRUS
• Flavi viruses: RNA
• Arbovirus group
• 4 serotypes – Den 1- 4
• Cycle involves humans and mosquitos
• Infection with one virus gives immunity to that serotype only
• Causes dengue and dengue hemorrhagic fever

6. EPIDEMIOLOGY
• First reported epidemics in 1779 –80 in Asia, Africa and North
America.
• Considered a mild non fatal disease
• Epidemics every 10-40 years due to introduction of new
serotype
• After World War II, pandemic of dengue which began in
Southeast Asia, expanded geographical distribution, epidemics
with multiple serotypes and emergence of DHF

7. • 1980s: a second re-expansion of DHF in Asia with epidemics in
India, Sri Lanka and Maldives, Taiwan, PRC; Africa and
Americas
• Progressively larger epidemics
• Primarily urban

8. Mainly in Urban and Semi Urban area

9. DENGUE GLOBALLY
 390 million dengue infections per year
 22,000 deaths, mostly among children.
 South America, South-East Asia and Western Pacific regions are the
most seriously affected.

10. Why the no. of cases keep increases worldwide ??
Increased air travel
Uneffective mosquito
control
Unreliable
drainage systems
Increasing
population

11. ETIOLOGY
• Vector - Aedes aegypti*
▪ bite during daytime
▪ Lays egg in clean & stagnant water
▪ Female feeds on blood
- Aedes alboticus
AEDES EGYPTI AEDES ALBOPTICUS

13. PATHOPHYSIOLOGY

14. TRANSMISSION

15. DENGUE CLASSIFICATION
There are actually four dengue clinical syndromes:
• Undifferentiated fever;
• Classic dengue fever;
• Dengue hemorrhagic fever, or DHF; and
• Dengue shock syndrome, or DSS.
• Dengue shock syndrome is actually a severe form of DHF.

16. Classic Dengue Fever
Dengue hemorrhagic
Fever
( > chances in ? )
Dengue Shock
Syndrome
In
critical
phase ,
Might
**Monitor
Warning
Signs***
Without or
without
haemorrhage
Clinical Manifestation

17. PATHOGENESIS OF PRIMARY INFECTION
 Incubation period : 4-7 days (range 3-14)
 Primary Dengue Infection – Self Limited
 May also progress to severe dengue (DHF/DSS) (normally children,
elderly & immunocompromised
PATHOGENESIS OF SECONDARY INFECTION
“Antibody dependent enhancement mechanism”
Infection by
virus of
another
serotype
Production
of non
neutralizing
antibodies
Facilitate
entry of virus
to
monocytes
through Fc
Receptor

18. More
Cytokines
Released
Acute increase
in vascular
permeability
Hypovolaemia
or shock or
death
Dengue
Hemorrhagic
Fever (DHF)
Dengue Shock
Syndrome
(DSS)
may

19. Clinical Manifestation
Dengue Virus Infection
Asymptomatic Symptomatic
Undifferentiated
fever
(viral syndrome)
Dengue fever
Mostly Without
hemorrhage
With unusual
hemorrhage
Dengue hemorrhagic
fever
(plasma leakage)
No shock Dengue shock
syndrome
Dengue fever
Severe Dengue
Secondary
Infection

20. PHASES
• Febrile Phase
• Critical Phase
• Recovery Phase

21. Febrile Phase x 7days
High fever 40 °C (104 °F)
headache
generalized arthalgia
myalgia
petechiae
bleeding from mucus membrane.
Arash occurs in 50–80%

22. Critical Phase x 2days
Leukopenia
thrombocytopenia.
Increase capillary permeability leading to plasma leakage that
lead to metabolic acidosis.
In children febrile phase is common carries nausea, vomiting,
thrombocytopnea.

23. Recovery phase x 2-3 days
Stabilize hemodynamic status
increase urine output
overall clinical improvement.
Increase in fluid overload can cause cerebral edema.

24. SIGN & SYMPTOMS of dengue( Based on WHO )
• Fever, Chills , ( more than 105 )
• headache
• Myalgia
• Arthralgia
• Retro-orbital pain
• Deep bone pain – “break bone fever”
• Rashes ( appear 4-5 days after fever )
• Positive Tourniquet
• Test

25. Symptoms – Dengue Fever Positive tourniquet test
Goal of the test :-
 To asses fragility of capillary walls
 To identify thrombocytopenia
 In DHF grade 1, a positive tourniquet
test serves as the only indicator of
haemorrhagic tendency
• 20 or more petechiae per 1
square inch. (MOH MALAYSIA
2014)

26. WARNING SIGNS
• Severe abdominal pain
• Persistent vomiting
• Vomit with blood
• Drowsiness or irritability
• Dyspnoea
• Swollen lymph node
• Prostration
• diarrhea
 Raised HCT, with rapid fall in platelet
 Fever to hypothermia
 Mucosal Bleed
 Liver Enlargement
Normal Male Hct 40.7 to 50.3%
• Normal Female Hct: 36.1 to 44.3%
• The normal number of platelets in the
blood is 150,000 to 400,000 platelets per
microliter (mcL).

27. The 4 WHO Criteria for DHF
 Fever
 Hemorrhagic
manifestations(Symptoms)
 Low platelet count (100,000/mm 3 or less
 Elevated hematocrit ( >20% then normal)
or ( > 50% THEN BASELINE)

28. Symptoms - Dengue Hemorrhagic Fever (DHF)
• petechiae
• epistaxis(nose bleed),
• gingival bleeding (gum bleed)
• Microscopic hematuria.

29. SYMPTOMS

30. DENGUE SHOCK SYNDROME
• It can trigger Dengue Shock Syndrome
– Massive bleeding
– Death
– Dehydration
– Febrile convulsion

31. DIAGNOSIS
History Clinical Lab
• History tells us the endemic area, previous dengue infection and etc
• Clinical diagnosis are all the symptoms.
We can make only provisional diagnosis
• Lab Diagnosis is the confirmatory

32. Lab Diagnosis – Is the Confirmatory test
Tests include
1. Serological Test – ELISA – To Detect Antibody
2. Non Structural Protein (NS1 antigen) Test
These 2 tests are most widely used diagnostic test
OTHER TEST
1. Virus isolation
2. RT-PCR

33. 1. Non Structural Protein (NS1 antigen) Test
• Latest diagnostic tool for diagnosing dengue
• Useful in the diagnosing in the early phase (3 to 4 of illness) Some
times even from second day of illness
• But It is not useful after 5 days of illness .
• Criteria for primary infection
• Postive NS1 antigen
• Criteria for secondary infection
• Usually Negative NS1 antigen
• rarely Can be postive as well

34. 2. Serological Test by ELISA – To Detect
Antibody (Ig M and Ig G)
• Criteria for primary infection
 Positive IgM after 5 to 7 days of illness
 Ig G present after 7 days
• Criteria for secondary infection
 Positive Ig G after 5 to 7 days onwards
 Usually Absence or slight increase in IgM after 5 to 7 days onwards

35. Rapid Test Combo Kit
• SD BIOLINE Dengue Duo
• (To detect Dengue NS1 Ag and IgG/IgM in a single test )

37. OTHER TEST
• Virus Isolation performed in the lab equipped with tissue culture and other
virus isolation facilities. blood should be collected before day 5 of illness –
before the formation of neutralizing antibodies.
• It may take up to two weeks to complete the test and it is expensive.
• PCR can be used as a diagnostic tool in early dengue infection .
• It is not recommended as a routine diagnostic test due to limited
availability and cost.

38. Lab Test for Provisional Diagnosis/ Screening Criteria
and disease monitoring purpose
Full Blood Count (FBC) White cell count (WCC) shows –
1 Leucopaenia
2 Thrombocytopaenia
3 Normal or raised HCT

40. COMPLICATION
1 Febrile phase - Dehydration
2 Critical phase - Shock from plasma leakage: severe haemorrhage;
organ impairment = Dengue Shock Syndrome
3 Recovery phase - Hypervolaemia
A small percentage of individual who have dengue fever can develop a
more serious form of disease
• Dengue haemorrhagic fever and disseminated intravascular coagulation
• Hepatitis, cerebral haemorrhage or oedema, encephalitis,
• cranial nerve palsies, rhabdomyolysis, myocarditis
• Vertical transmission if infection within 5 wks of delivery

41. MOST OF YOU GET CONFUSED THAT
WHAT IS DENGUE HEMMORAHAGIC FEVER AND
DENGUE SHOCK SNDROME
ALWAYS REMEMBER
THEYARE THE COMPLICATION OF DENGUE FEVER

42. CONTROL AND PREVENTION
• Vector Control
• Individual Preventive Measures
• Immunization
- Sanofi Dengvaxia
- All for types

43. TREATMENT
• No specific treatment , only Supportive therapy
• No antiviral agents are of proven value
• Fluid replacement and Monitor the Ht and Platelet Count
MANAGEMENT
• Bleeding prevention & control
• Fluid & water replacement
• Symptoms relief & fever control

44. *Only* for severe cases ( DHF and DSS )
• Close monitoring of hypotension/shock
• IV. Infusion of crystalloids/colloids
• Oxygen administration
• Platelet transfusion
• Clotting factors replacement

46. PROGNOSIS
• For the majority of peoples the people infected with dengue
virus fever the prognosis is excellent.
• Although they are likely to feel very ill during first 1-2 week of
acute illness.
• Overall the fatality rate is about 1% for all denge fever
infection.

47. REFERENCE
1. k. Park , park’s textbook of preventive and social medicine, February 2011, 21st Edition,
Published Banarsidas Bhanot Publishers
2. Nettina S. M., Lippincott manual of nursing practice ,2016, 10th edition, Jaypee
brothers.
3. James S R , Kristine N, Jean A., Nursing Careof Children: Principles and Practice, 2014,
4th Edition,Elsevier.
4. D. L. Wong, L. F.Whaley, Essentials of Pediatric Nursing ,January 15, 1997,5 th
edition,Mosby
5. Mentor : AP. DR. Durgadas , IMS – MSU
6. Book : Lange Microbiology 14th edition
7. Guidelines : MOH Malaysia 2014 and WHO 2014
8. Journal : International Medical Journal Malaysia ( IMJM)
9. Official Portal : Selangor Health Department
10. Online web site : Medscape
11. Picture Source : Flicker , Google Images