|PREVALENCE OF NON-SPECIFIC SENSITIVITY TO TUBERCULIN
IN A SOUTH INDIAN RURAL POPULATION
|AK Chakraborty, KT Ganapathy, SS Nair & Kul Bhushan:
Indian J Med Res 1976, 64, 639-51.
The data from a tuberculosis prevalence survey
carried out in three taluks of Bangalore district in south India
during 1961-68 were analysed to study (i) the prevalence of non-specific
sensitivity in the community i.e., prevalence of infection with
mycobacteria other than M.tuberculosis, as found by testing the
population with tuberculin RT 23 of a lower strength (1 TU) and
higher strength (20 TU), both with Tween 80 and (ii) additional
boosting if any, resulting from testing with higher dose of tuberculin,
immediately following a test with 1 TU RT 23.
The level of demarcation between infected and uninfected
with 1 TU was 0-9 mm induration size and this negative group tested
with 20 TU dose induration of 8 mm or more was considered positive.
Prevalence of infection with M.tuberculosis in the community were
2.1% in 0-4 years, 7.9% in 5-9 years, 16.5% in 10-14 years, 33.2%
in 15-24 years and overall 14.5% in 0-24 years of age group. Infection
rate with other mycobacteria were 12.9%, 44.9%, 66.2%, 62.4% and
45.7% respectively in the above stated different age groups.
Testing the population with 20 TU RT 23 following
a 1 TU test was found not to boost the tuberculin reactions over
that observed on a single test with 1 TU only.
|KEY WORDS: NTM, PREVALENCE, INFECTION, BOOSTING,
TUBERCULIN REACTION, RURAL POPULATION.