Comparative evaluation of varied antibody response to SARS-CoV-2in asymptomatic High risk versus Low risk population: A cross sectional serosurvey at Sirmour District, Himachal Pradesh, India

Abstract

ABSTRACT

Covid -19 disease is a respiratory illness caused by novel Severe Acute Respiratory Syndrome Corona virus-2 (SARS

CoV-2). Serological testing in Covid -19 infection can facilitate diagnostic utility for case management especially in

later stages of the disease when the sensitivity of RT-PCR to diagnose COVID -19 lower. There are limited studies

from low and middle-income countries like India regarding this. So, this study was designed for Comparative

evaluation of the varied antibody response to SARS-CoV-2 in asymptomatic high risk versus low risk population at

District level.

Method

High risk and low risk individuals were selected based on convenience sampling at the various health institutes of

District at Block level. ELISA IgG blood test kits provided by the state government for serosurvey were used.

CovidKavach Anti SARSCoV-2 Human Ig ELISA kit intended for detection of IgG antibodies, manufactured by

Trivitron health care and validated by ICMR, NIV Pune was used.

Results

Seroprevalence of SARS COV2 was assessed among 470 health care workers and 331 participants from general

population. Overall seropositivity for SARS CoV 2 was present in 61(12.9%) health care workers. No significant

difference was present in various parameters like age, gender and profession between seropositive and

seronegative health care workers except block wise distribution (p<0.001). Among general population, overall

seropositivity for SARS CoV 2 was present in 30/331(9.0%). Seroprevalence in this study is seen to be higher in males

than in females, both in general population and health care workers (HCW). However, no correlation was found

between Diabetes, Asthma or Hypertensive patients and IgG positivity among HCW or general population. The

study highlights the role of seroprevalence detection in asymptomatic or undetected infections in both groups.