KUMJ | VOL. 18 | NO. 2 | ISSUE 70 | COVID-19 SPECIAL 2020
Sensitivity and Specificity of Lateral Flow Antigen Test Kits for COVID-19 in Asymptomatic Population of Quarantine Centre of Province 3
Shrestha B, Neupane AK, Pant S, Shrestha A, Bastola A, Rajbhandari B, Thapa A, Singh A
Abstract: Background
Nearly after 6 months of the spread of Corona Virus Disease 19, along with the
world Nepal is still trying to control the spread and prevent general population
from acquiring it. With limited resources in manpower, technology and evidence
it has been a difficult battle. But with time and more understanding of the virus
new technology to detect the virus are coming up. It is a major breakthrough in the
diagnostic field as this helps us in not only detecting the virus but also helps us to
mobilize our human resources. This comes in a time where the cases are increasing
at an alarming rate. Although numbers of Polymerase Chain Reaction testing have
increased but due to the time consuming and the cost wise, we need a faster and
equally reliable alternative. Antigen test approved by different countries can be used
for point of care, screening and surveillance depending upon the requirements after
calculating its sensitivity, specificity and accuracy.
Objective
To find out sensitivity and specificity of the Antigen test kit for COVID-19.
Method
Antigen tests were compared with Reverse Transcription Polymerase Chain Reaction
as a reference standard in calculated sample size of 113 subjects in a high risk
population. Both Reverse Transcription Polymerase Chain Reaction and antigen test
were performed in a same subject with in maximum of 2 days’ interval. Convenience
sampling technique was used to select the subjects. Ethical approval was taken from
Nepal Health Research Council before data collection. Study was done from August
to September 2020 from Quarantine center of Province 3.
Result
There were total of 113 test carried out, among those 47 were positive and 66 were
negative in Reverse Transcription Polymerase Chain Reaction. After preparing two by
two table, Sensitivity and specificity of the tested was calculated which came out to
be 85% and 100% respectively, with accuracy of 93.80%.
Conclusion
Even though the sensitivity and specificity came to be higher, this test should be
interpreted cautiously depending upon the prevalence of Corona Virus Disease 19 in
that particular community and the clinical and epidemiological context of the person
who has been tested. When in doubt by clinical correlation should be confirmed with
Reverse Transcription Polymerase Chain Reaction.
Keyword : Asymptomatic, Coronavirus Disease 19, Lateral flow antigen test, Sensitivity
