Tubercular infection in children living with adults receiving Directly Observed Treatment Short Course (DOTS): a follow up study

Background Children living with sputum smear-positive adult tuberculosis (TB) patients are vulnerable to acquire tubercular infection. Contact tracing is an important strategy to control tubercular infection in the community. This study was done to find out prevalence of tuberculosis and tubercular infection in children living with sputum smear-positive adult patients receiving DOTS at recruitment and to find out incidence of tubercular infection and disease in these children on follow up. Method Children (< 15 years) living in contact with adults on DOTS were grouped as < 6 years and 6-14 years. They were further sub grouped as being - uninfected, infected, diseased and on prophylaxis and were followed at 3, 6 and 9 months. Tuberculin skin test (TST) and chest X-ray were done. Results At recruitment 152 children were enrolled and 21.1% (n = 32) had TB. On follow up, 4.3% (n = 5), 5.8% (n = 6) and 11.6% (n = 11) children developed TB after 3, 6 and 9 months respectively.9 children did not come for the last follow up so the overall prevalence of TB disease at 9 months was 37.7% (n = 54). Out of the 128 children with TST reading 23.4% (n = 30) child contacts were found to be infected already at recruitment. The incidence of TST conversion was 20.7% (n = 18), 26.9% (n = 18) and 16.3% (n = 7) respectively. The overall prevalence of tubercular infection in the children, who were in contact with TB patients for 9 months was 74.5% (n = 73). Conclusion About half the children were either suffering from TB or tubercular infection on recruitment. During 9 months follow up 22 unaffected children developed disease and 43acquired infection.