The third round of sero surveys will be launched by Haryana on Tuesday to determine the prevalence of coronavirus antibodies in people, including children 6 and older. “It will help us to plan and consolidate our paediatric services, including the creation and expansion of intensive care units. The study will flag populations and areas susceptible to vaccination in those areas, helping us to channel and prioritise immunisation in those areas,” said Rajeev Arora, Heath Secretary, last week. The study also contributes to the effect and effectiveness of vaccination. Arora stated.
The Senior Functionary stated that the third round of the sero survey was underway to detect the impact on the community of the second coronavirus wave. In August, seroprevalence was found to be 8 percent in the first round. In October, it rose to 14.8%.
How it is done?
The scale of undetected infections is taken from randomly selected persons in the sero survey. The presence of IgG (Immunoglobulin G) antibodies which determine a previous virus infection is tested in the blood samples in a sero survey. Sero surveys are important to determine if the disease is transmitted to the community.
The IgG Enzyme Linked Immunosorbent Assay (ELISA) test is part of a serological examination. It estimates the share of Sars-Cov-2 exposed population. The IgG test is not useful to detect acute infections, but it shows episodes of previously occurring infections. For its high sensitivity and specificity, the test is approved by ICMR.
What have the results of previous sero surveys in India revealed?
Earlier sero surveys suggested that a large portion of the population was still susceptible to the virus, and India was still far from achieving herd immunity. The first was a cross-sectional survey of adults aged 18 and up from 21 states, with districts divided into four strata based on the number of Covid-19 cases per million population reported.
In May of last year, the first sero survey revealed a national infection rate of 0.73 percent. In the second, nearly one in 15 (6.6 percent) people over the age of ten were found to be infected with the virus until August 2020. The third sero survey, which took place between December 17, 2020, and January 8, 2021, found that 21.4 percent of those aged 10 and up were infected with the virus.
Except for the age bracket, which was taken from people aged 10 and up in the second and third rounds, all other parameters remained the same.
When is the fourth national sero survey scheduled to begin?
The fourth round of sero surveys by the Indian Council of Medical Research (ICMR) to detect the prevalence of Sars-CoV-2, the virus that causes coronavirus disease (Covid-19), will start this month in 70 districts across 21 states. Blood samples will also be taken from health-care workers in these districts’ district hospitals.
States, where the samples will collected for sero survey, include Andhra Pradesh (Krishna, SPSR Nellore, Vizianagram), Assam (Udalguri, Kamrup Metropolitan, Karbianglong), Bihar (Muzaffarpur, Purnia, Begusarai, Madhubani, Buxar, Arwal), Chhattisgarh (Bijapur, Kabirdham, Surguja), Gujarat (Mahisagar, Narmada, Sabar Kantha), Jharkhand (Latehar, Pakur, Simdega), Karnataka (Bengaluru urban, Chitradurga, Kalaburagi), Kerala (Palakkad, Ernakulam, Thrissur), Madhya Pradesh (Dewas, Ujjain, Gwalior), Maharashtra (Beed, Nanded, Parbhani, Jalgaon, Ahmednagar, Sangli), Odisha (Rayagada, Ganjam, Koraput), Punjab (Gurdaspur, Jalandhar), Haryana (Kurukshetra), Rajasthan (Dausa, Jalore, Rajsamand), Tamil Nadu (Tiruvannamalai, Coimbatore, Chennai), Telangana (Kamareddy, Jangaon, Nalgonda), and Uttar Pradesh (Amroha).
