Send to

Choose Destination
Int J Tuberc Lung Dis. 2013 Mar;17(3):312-9. doi: 10.5588/ijtld.12.0330. Epub 2013 Jan 14.

Trends in the annual risk of tuberculous infection in India.

Author information

Epidemiology and Research Division, National Tuberculosis Institute, Bangalore, India.

Erratum in

  • Int J Tuberc Lung Dis. 2013 Jun;17(6):851.



Twenty-four districts in India.


To evaluate trends in annual risk of tuberculous infection (ARTI) in each of four geographically defined zones in the country.


Two rounds of house-based tuberculin surveys were conducted 8-9 years apart among children aged 1-9 years in statistically selected clusters during 2000-2003 and 2009-2010 (Surveys I and II). Altogether, 184,992 children were tested with 1 tuberculin unit (TU) of purified protein derivative (PPD) RT23 with Tween 80 in Survey I and 69,496 children with 2TU dose of PPD in Survey II. The maximum transverse diameter of induration was measured about 72 h after test administration. ARTI was computed from the prevalence of infection estimated using the mirror-image method.


Estimated ARTI rates in different zones varied between 1.1% and 1.9% in Survey I and 0.6% and 1.2% in Survey II. The ARTI declined by respectively 6.1% and 11.7% per year in the north and west zones; no decline was observed in the south and east zones. National level estimates were respectively 1.5% and 1.0%, with a decline of 4.5% per year in the intervening period.


Although a decline in ARTI was observed in two of the four zones and at national level, the current ARTI of about 1% in three zones suggests that further intensification of TB control activities is required.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Ingenta plc
Loading ...
Support Center