ABSTRACT
Background & objectives: The National Prevalence Survey of India (2019-2021) estimated 31 per cent tuberculosis infection (TBI) burden among individuals above 15 years of age. However, so far little is known about the TBI burden among the different risk groups in India. Thus, this systematic review and meta-analysis, aimed to estimate the prevalence of TBI in India based on geographies, sociodemographic profile, and risk groups. Methods: To identify the prevalence of TBI in India, data sources such as MEDLINE, EMBASE, CINAHL, and Scopus were searched for articles reporting data between 2013-2022, irrespective of the language and study setting. TBI data were extracted from 77 publications and pooled prevalence was estimated from the 15 community-based cohort studies. Articles were reviewed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines and were sourced using a predefined search strategy from different databases. Results: Out of 10,521 records, 77 studies (46 cross-sectional and 31 cohort studies) were included. The pooled TBI prevalence for India based on the community-based cohort studies was estimated as 41 per cent [95% confidence interval (CI) 29.5-52.6%] irrespective of the risk of acquiring it, while the estimation was 36 per cent (95% CI 28-45%) prevalence observed among the general population excluding high-risk groups. Regions with high active TB burden were found to have a high TBI prevalence such as Delhi and Tamil Nadu. An increasing trend of TBI was observed with increasing age in India. Interpretation & conclusions: This review demonstrated a high prevalence of TBI in India. The burden of TBI was commensurate with active TB prevalence suggesting possible conversion of TBI to active TB. A high burden was recorded among people residing in the northern and southern regions of the country. Such local epidemiologic variation need to be considered to reprioritize and implement-tailored strategies for managing TBI in India.
ABSTRACT
Background & objectives: Serosurvey of COVID-19 provides a better estimation of people who have developed antibodies against the infection. Undertaking such a serosurvey in certain districts of India which are densely populated with prominent tribes can provide valuable information regarding seropravelance of SARS-CoV-2 antibodies among such indigenous populations. In this context, two rounds of population-based, cross-sectional serosurveys for SARS-CoV-2 IgG antibody were carried out in Jharkhand, a tribal-dominated State of India, to compare the seroprevalence of SARS-CoV-2 infection and to determine the associated demographic risk factors. Methods: The surveys were carried out in June 2020 and February 2021 in ten districts of the State of Jharkhand. Blood samples were collected from the residents of the selected districts by random sampling and tested for anti-SARS-CoV-2 antibodies using an automated chemiluminescence immunoassay platform. A total of 4761 and 3855 eligible participants were included in round 1 and round 2, respectively. Results: The age- and gender-standardized seroprevalence for COVID-19 during round 1 was 0.54 per cent (0.36-0.80) that increased to 41.69 per cent (40.16-43.22) during round 2 with a gap of eight months in between. The seropositivity among male and female participants was 0.73 and 0.45 per cent, respectively, during the first round and 51.35 and 33.70 per cent, respectively, during the second round. During the first round, 17.37 per cent of the participants were tribal with seropositivity of 0.24 per cent (0.02-0.87), and during the second round, 21.14 per cent were tribal with seropositivity of 39.14 per cent (35.77-42.59). Compared to tribal group, non-tribal participants had an adjusted odds of 1.24 (95% confidence interval=1.04-1.48) for SARS-CoV-2 seropositivity. Interpretation & conclusions: COVID-19 seroprevalence was found to be low during the first round (0.54%) of the survey, possibly due to the travel restrictions during lockdown better adherence to social distancing and wearing of face masks among the people. Understanding the dynamics of SARS-CoV-2 transmission and the susceptibility to infection at the individual as well as community level will inform decision and help policy makers to design and implement effective public health strategies to mitigate the pandemic in this State.