New ICMR plan for states to expand antibody tests

After finishing a pilot sero-survey (a test of the blood serum of a bunch of people) final week to verify the extent of publicity to the Sars-CoV-2 virus that causes Covid-19 in the neighborhood utilizing Elisa-based antibody testing, the Indian Council of Medical Research’s (ICMR) on Saturday despatched an advisory to all states to broaden the survey.

ICMR has ready a complete checklist of classes of people that needs to be examined as a part of the sero survey, together with high-risk or susceptible populations (health-care employees, frontline employees, immune-compromised people, people in containment zones, safety workers, prisoners) to know who has been contaminated up to now and has now recovered.

“ICMR conducted the pilot survey to get a basic sense of how India is in terms of disease spread currently, for which the results should be out in some time. However, periodic sero-surveys are necessary to establish a trend and the states have been asked to take it forward and keep doing it periodically to know the prevalence of the disease at ground level,” mentioned a senior ICMR official, who didn’t want to be recognized.

The blood samples can be examined for detecting IgG antibodies utilizing the Elisa methodology ((IgG is an antibody that develops later as in comparison with the opposite antibodies, therefore, determines a previous an infection). The Elisa methodology is an enzyme-based laboratory test that detects and quantifies antibodies in blood that can decide a previous an infection because of the virus.

For a number of viral infections, antibody checks are helpful for illness detection after 5–7 days of sickness. Understanding associated to antibody checks for Covid-19 is evolving and a number of other checks are being developed globally. The IgG antibodies typically begin showing after two weeks of the onset of an infection, as soon as the person has recovered after an infection and final for a number of months. The IgG test shouldn’t be helpful for detecting acute an infection however signifies episodes of Sars-CoV-2 an infection up to now, say specialists.

“Sero-surveys help to understand the proportion of population exposed to Sars-CoV-2 infection including asymptomatic individuals. Depending upon the level of sero-prevalence of infection, appropriate public health interventions can be planned and implemented for prevention and control of the disease. Periodic sero-surveys are useful to guide the policy makers,” mentioned ICMR in a press release.

Scientists at ICMR-National Institute of Virology, Pune have developed and validated an indigenous IgG Elisa test for antibody detection for Sars-CoV-2.

The test has undergone intense validation in three phases and has been discovered to have excessive sensitivity and specificity. To fast-track manufacturing and enhance availability of the IgG Elisa test, ICMR has transferred this know-how to many pharma firms reminiscent of Zydus Cadila, J Mitra & Company, Meril Diagnostics, Voxtur Bio, Trivitron Healthcare, Karwah Enterprises and Avecon Healthcare.

“The technology has been transferred to various entities without exclusivity clause and therefore can be further shared with others as per demand and capability. ICMR has offered to provide technical support to States/ UTs, if required, in planning and carrying out sero-surveys using IgG Elisa test kits and also interpreting the results,” mentioned the analysis physique.

Experts on infectious ailments, nevertheless, really feel that merely figuring out whether or not the inhabitants has developed antibodies towards the virus shouldn’t be sufficient.

“Merely knowing the volume of people who have been infected will only provide the sense of the spread of the disease; what we must try to know is the quantity and quality of antibodies being produced against the virus. Also, for how long these antibodies stay in human blood so as to know if it’s enough to offer protection against the disease,” says Dr Lalit Kant, former head of the epidemiology division at ICMR