Right now the whole world is facing the covid-19 pandemic, and right now diagnosis and prevention of the spread of disease is the best option we have. This presentation includes methods that are currently in use for the identification of SARS-Co-V 2 / Covid-19. other than currently used methods this presentation also includes potential wearable devices that can be used for early detection of Covid-19.
2. Coronavirus disease 2019 (COVID-19) is caused by a novel coronavirus (CoVs), named severe acute
respiratory syndrome coronavirus 2 (SARS-CoV-2) [provisionally known as 2019 novel coronavirus
(2019-nCoV)].
• It originated in central China's Wuhan city anywhere from March to September 2019, and spread rapidly to
nearly the entire world, with more than 4 million deaths and 195 million cases.
• The World Health Organization (WHO) on March 11, 2020, has declared the novel coronavirus (COVID-19)
outbreak a global pandemic.
• The exponential growth of SARS-CoV-2 is a result of its high reproduction numbers (R0) ranging from 2.2
to 3.58, with an average of 2.67.
• The major problem with infectious disease like covid 19 is exponential spread of the disease, thus
diagnosis and isolation of infected individuals provides the best approach in controlling disease spread.
A pandemic is an epidemic of an infectious disease that has spread across a large region, for
instance, multiple continents or worldwide, affecting a substantial number of people.
Executive Summary | COVID-19
3. • To control the spread of covid 19 or other
infectious diseases generally, some common
strategies are available.
• Such as;
• Proper and reliable diagnosis of disease.
• Isolation of infected individuals.
• Social distancing.
• Contact tracing.
• Quarantine.
• Other covid appropriate behaviours.
Identifying who infected people have come into contact with, known as contact tracing, is a very
important step in detecting potentially infected individuals and preventing further spread.
Prevention | COVID-19
4. • Diagnosis plays a major role in controlling the outbreak of infectious diseases like COVID 19. Currently,
many techniques and kits are available for detection of covid 19, and many are under development to
increase efficacy and efficiency of diagnosis. When the diagnosis is accurate and done in a timely
manner, the patient has the best chance for a positive health outcome, and it also prevents the further
spread of the infection.
• Some common diagnosis strategies are;
Diagnosis has been described as both a process and a classification scheme, or a “pre-existing
set of categories agreed upon by the medical profession to designate a specific condition”
Diagnosis | COVID-19
• Viral genetic material (RNA) detection
• Detection of antibodies against viral
antigens in serum
• Detection of viral antigens in body
fluids
• presence of physical symptoms
• Image-based test for a lung
infection
• Biosensors for early detection of
infection
5. • The Real-Time reverse transcription- Polymerase Chain Reaction (rRT-PCR) test is the "gold
standard" for the diagnosis of COVID-19 because of its accuracy.
• The assay uses viral RNA extracted from patient samples (such as material collected by NP/OP swabs),
synthesizes complementary DNA (cDNA) through the action of the reverse transcriptase enzyme, amplifies
target sequences of the SARS-CoV-2 genome from the cDNA template using multiple primer and probe,
thus it could discriminate SARS-CoV from other human and animal coronaviruses.
• Failure to expand can be interpreted as a negative result, but it can also be due to poor quality of the
clinical sample or to early disease status.
• NGS (Next Generation Sequencing) is an alternative approach that can be used for this purpose. In
addition to diagnosing infection, it can also provide information about new mutations in the viral genome.
Viral Nucleic Acid Detection | COVID-19
rRT-PCR, preferably, should be performed between the third and fifth day after the onset of
symptoms, as the viral load is usually high in the first week of illness.
Emery SL, Erdman DD, Bowen MD, et al. Real-time reverse transcription-polymerase chain reaction assay for SARS-associated coronavirus. Emerg Infect Dis. 2004;10(2):311-316.
doi:10.3201/eid1002.030759
First NGS-based COVID-19 diagnostic. Nat Biotechnol 38, 777 (2020). https://doi.org/10.1038/s41587-020-0608-y
6. • Several POCT kits are currently available for the rapid detection of viral genomes, specific viral protein
antigens, or antibodies in host blood.
• Isothermal Nucleic Acid Amplification Assay amplified the target sequence at a constant temperature of
60–65 °C using primers and a polymerase with high strand displacement activity in addition to a replication
activity. The amplification product can be detected via photometry, which measures the turbidity caused by
magnesium pyrophosphate, which occurs as a byproduct of amplification.
• Some molecular POCT kits are:-
• iLACO, by sangyang university; based on RT-LAMP.
• ID-NOW COVID 19, by Abbott; based on ID NOW instrument.
• Sherlock CRISPR SARS-CoV-2 kit, by sherlock bioscience; based on RT-LAMP and CRISPR-cas13.
Molecular point-of-care tests | COVID-19
Point of care testing (POCT) allows rapid medical diagnostic testing at or near the actual point of
care such as in a physician's office, ambulance, home, field, or hospital that lacks laboratory
infrastructure to allow rapid treatment.
7. Immunological assay such as ELISA can be used in detection of antibodies or viral protein as diagnosis test
for covid 19.
• Serological tests, use ELISA to detect the presence of immunoglobulins M and G against coronavirus in
a whole blood, plasma or serum sample. These tests can determine whether a patient has previously
been infected with coronavirus, as they will stay positive after active infection has gone. These tests will
not be positive until the body has started to make antibodies to fight the virus, typically 5-10 days post-
infection.
• Example; “SARS-CoV-2 IgG assay” by “abbott laboratory” detect IgG antibody in serum or plasma.
• Antigen test detect the presence of viral antigen in patient biological sample using immunological assay.
• Currently “Sofia 2 SARS Antigen FIA”, “Coviself” and other antigen test kit are commercially available
which detect presence of nucleocapsid protein antigen of SARS-CoV-2 in nasopharynx swab.
The enzyme-linked immunosorbent assay (ELISA) uses a solid-phase type of enzyme immunoassay
(EIA) to detect the presence of a ligand (commonly a protein) in a liquid sample using enzyme-linked
antibodies directed against the protein to be measured.
Protein test | COVID-19
8. • Physical signs and symptoms can be used to diagnose the disease but in the case of covid 19, these
symptoms and their severity can vary between asymptomatic, mild, and severe patients. physical
symptoms can develop from 2 days to 2 weeks after exposure to the virus.
• some common symptoms of covid 19 :
Physical symptoms are abnormalities that can indicate a possible medical condition and serve as
objective evidence of a disease that can be observed by others or only by the patient.
• Fever or chills
• Cough
• Shortness of breath
• Fatigue
• Muscle or body aches
• Headache
• hyposmia and anosmia
• Sore throat
• Congestion or runny nose
• Nausea or vomiting
Physical Examination | COVID-19
9. • Imaging tests to diagnose COVID-19 were usually done with an HRCT scan or chest X-ray. It has been
reported that CT imaging of lesions may exhibit major distributions in the subpleural region or may barely
exist along with bronchial vascular bundles. Quantitative analysis demonstrated the existence of one to
two and often more than three lesions at random. Their morphology was observed to be nodular, lumpy,
or patchy. Furthermore, the density was found to be mostly uneven along the condensed bronchial wall.
Other associated signs vary from air-filled bronchi, enlarged lymph nodes (mediastinal), and rarely pleural
effusion.
• Medical research bodies like ICMR, American College of Radiology (or ACR) has issued guidance that
CTs and x-rays should not be used as a first-line tool to diagnose or screen for COVID-19. There are
some major reasons for the ACR’s recommendation, such as;
• A chest CT or x-ray cannot accurately distinguish between COVID-19 and other respiratory
infections, like seasonal flu.
• A significant percentage of patients with COVID-19 have normal chest CTs or x-rays.
Image-based test | COVID-19
High-resolution computed tomography (HRCT) is a type of computed tomography (CT) that use
radiology with specific techniques to enhance image resolution.
10. Laboratory parameters Abnormalities
Lymphocytes Reduction
Eosinophils Reduction
Hemoglobin (Hb) Reduction
Albuin Reduction
Procalcitonin Increase
Lactate dehydrogenase (LDH) Increase
D-dimer Increase
C-reactive protein(CRP) Increase
Creatinine Increase
Creatine kinase (CK) Increase
Pro-inflammatory Cytokines such as IL-1β, IL-2, IL-4, IL-6, TNF-α and IFNγ Increase
A hematologic examination is the microscopic examination of the cells of the blood looking for
changes in the structure and numbers of various types of blood cells.
Hematological and Biochemical Examination
11. Pre-screening | COVID-19
• As COVID 19 shows many different patterns of physical symptoms it becomes difficult to identify infected
persons (asymptomatic) who do not show proper physical symptoms but can spread the disease.
• Thus, pre-screening by a wearable device that can detect subtle changes in respiratory function and body
temperature before the onset of clinical symptoms, such as shallow respiration, wheezing and shortness
of breath has the potential to be an effective tool.
• Many Wearable devices are available to major physical symptoms like,
• Temperature
• Blood oxygen saturation
• Respiration rate (RR)
• Heart rate variability (HRV)
Pre-screening is very important for individuals who are at high risk of infection like a frontline
staff so that they can isolate themselves before spreading the disease to others and get proper
treatment in time.
12. • Wearable devices can detect and alert users of possible infection with SARS-CoV-2 before they develop
clinical symptoms through the development of an early detection algorithm (EDA). By notifying wearable
device users of possible early infection, EDA could allow them the ability to self-isolate, seek care or
diagnostic testing, and take other steps to mitigate transmission of the infection during a critical period of
the disease process.
• Some commercially available wearable devices;
• TempTraq®, a wearable temperature monitor in the form of a soft, comfortable patch that continuously,
safely and comfortably, monitors body temperature for up to 48 hours and sends alerts to a smartphone
using Bluetooth connectivity.
• Oura ring and other fitness bands, major Resting Heart Rate, Heart Rate Variability (HRV), Respiratory
Rate, Body Temperature, Light, Deep and REM Sleep, Nighttime Movement, Sleep Timing and Quality
and physical movements of body.
• Pulse oximetry, can major Peripheral oxygen saturation readings within 2% accuracy.
Early Detection Algorithm(EDA) | COVID-19
Computational algorithms with wearable devices can analyze biological data and detect any
infection prior to any major physical symptoms.
13. • Proper diagnostic methods cost money and require time so cannot be used on the general public
in daily life. Thus, certain symptoms are commonly used as indicators of infection.
• Currently, some common general screening methods or indicators are used to test infected
persons in public places.
• Such as;
• Body temperature: High body temperature or fever is a common symptom of COVID 19 and
temperature detection is a very simple, cost-effective, time-efficient method that does not require
skilled manpower.
• Breath sound: Since patients infected with COVID-19 show changes in physical breath sound or
cough sound, this can be used as a test for screening using machine learning techniques.
• Smell Identification test; Loss of smell either anosmia or hyposmia is a prominent marker of covid
19. Testing for anosmia or hyposmia can be done using a scratch card of micro-encapsulated
odorant.
These tests alone are not sufficient for diagnosis of COVID 19 due to high false results.
General screening | COVID-19
14. • Nearly 20 months have passed since the first case of Covid-19 was reported and the whole world
has seen several phases of lockdown. The lives of about 3 trillion people have come to a
standstill.
• Currently around 300 thousand new cases are being reported daily around the world. In which ~40
thousand are only from India.
• The condition of the pandemic is different in different countries. Some countries are facing the
second wave and in some, the advisory is being issued for the third wave.
• Cure and treatment methods are being explored all over the world, but any concrete treatment for
medical use in humans is still far away.
• But as history tells, prevention is the best cure. Therefore, vaccination is currently being
considered as a strong remedy all over the world. Widespread vaccination campaigns are going
on in many countries to build a Hard immunity.
• In India alone, about 50 lakh people are getting the vaccine every day.
Prevention is the best cure.
Current situation | COVID-19