: The city-based ICMR-NationalInstitute of Nutrition (NIN) on Friday said it has initiated community-based sero-surveillance in Telangana, in association with the state government, to monitor the trend of SARS-CoV-2 infection transmission in the community.The survey would be carried out in 30 villages across three districts Jangaon, Kamareddy and Nalgonda, the NIN said in a press release.The NIN said it has been observed that severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) causes asymptomatic infection for which sero-surveillance (the monitoring of the presence or absence of specific substances in the blood serum of a population) is strongly recommended for active case finding, testing and contact-tracing.Also, surveillance of antibody-based sero-positivity (having or being a positive serum reaction especially in a test for the presence of an antibody) indicates the extent of spread of infection in the given population and forms the basis for strengthening public health mitigation measures, the release said.Household-based studies can generate evidence on role of asymptomatic and mild infections in transmission.To establish the community-based district-level sero- surveillance and to monitor the transmission of SARS-CoV-2 infection in the general population, a nation-wide survey has been initiated throughout the country by the ICMR (Indian Council of Medical Research), it said.In Telangana, three districts - Jangaon, Kamareddy and Nalgonda - have been selected. In each district, 10 villages would be selected randomly, and from each village 40 adults (18 years) men and women would be randomly covered for the study, the release said.The study would be carried out in four rounds in the same villages (repeat cross-sectional study). The initial survey would serve as a baseline to determine the sero- prevalence (the frequency of individuals in a population that have a particular element in their blood serum) of SARS-CoV-2 infection in the community.The subsequent rounds would help to monitor the trends of infection in the community.Population-based sero-epidemiological (relating to, or being epidemiological investigations involving the identification of antibodies to specific antigens in populations of individuals) studies would help in determining the burden of COVID-19 infection at the community-level and to monitor the trends in transmission of SARS-CoV-2 infection.The study findings would be useful in designing and implementing appropriate containment measures.The objectives of the sero-surveillance are to estimate and monitor the trend of sero-prevalence for SARS- CoV-2 infection in the general population and high burden cities, determine the socio-demographic risk factors for SARS-CoV-2 infection, and delineate the geographical spread of the infection in the general population and hotspot cities, thre release said.For this purpose, the NIN, in association with the state government, has initiated the house-to-house survey in 30 villages across three districts, it added.