ICMR says indigenous ELISA kits 92.37% sensitive, 97.9% specific for COVID-19 testing

The Indian Council of Medical Research (ICMR) has published its latest scientific paper in which it says indigenous IgG-based ELISA kits for COVID-19 testing will be useful in screening healthcare workers, industry workers, and other people exposed to the virus. The kits have been found to be sensitive and specific for the detection of coronavirus infection in human serum samples.

A total of 513 blood samples (131 positives, 382 negatives for SARS-CoV-2) were collected and tested by micro-neutralization test (MNT).

"The virus neutralization is regarded as the gold standard method for a serological assay. The in-house ELISA results correlated strongly with neutralization assay, indicating that the assay was sensitive and specific for the detection of anti-SARS-CoV-2 IgG," ICMR paper said. "The developed ELISA was found to be 92.37 per cent sensitive, 97.9 per cent specific, robust and reproducible. The positive and negative predictive values were 94.44 and 98.14 per cent, respectively," stated ICMR findings.

READ | Delhi Govt Issues Notice To Labs For Defying ICMR Guidelines; Submitting Covid Tests Late

READ | ICMR Issues List Of Approved Ig-ELISA Kits To Be Used For COVID-19 Serosurvey & Monitoring

Detect exposed immune-protected individuals

The assay performance was not different with the use of serum or plasma. No cross-reactivity with other respiratory viruses was detected. This kit may be used to detect exposed immune-protected individuals. This ELISA will be useful in screening healthcare workers, industry workers, etc.

According to ICMR, for surveillance of the emerging and re-emerging viruses, serological assays have been widely recommended. Several IgM/IgG ELISA kits for COVID-19 are in the stage of development.

However, validated and approved SARS-CoV-2 (the virus that causes COVID-19 disease) serological assays are lacking for case detection and are not included in laboratory testing guidelines for COVID-19 of the World Health Organisation (WHO).

"Due to the non-availability of an indigenous, approved and cost-effective kit, an in-house ELISA was developed and validated for the detection of anti-SARS-CoV-2 human IgG antibodies," read the paper. The ELISA kits can be produced at lower manufacturing costs. It gives easy-to-use and affordable kits to resource-limited settings.

The study concluded that this indigenous anti-SARS-CoV-2 human IgG-ELISA may be used for ascertaining the seroprevalence against SARS-CoV-2 in a population and for epidemiological studies.

(With ANI inputs) (AP Photo for representation)

READ | India Testing 1.2 Lakh Samples For COVID-19 Daily, Outreach Has Increased: ICMR

READ | Senior ICMR Scientist Tests Positive For Coronavirus