Diseases & National Health Programme
Which of the following is false about annual risk of TB? (DNB June 09)
|A||ARI of 1 percent = 75 new cases|
|B||Current ARI in India is 1.7%|
|C||It represents new cases of TB|
|D||It is assessed by tuberculin conversion in previously non vaccinated children|
Incidence of infection: (Annual Infection Rate): It is the percentage of population under study who will be newly infected by Myco. tuberculosis among the non -infected of the preceding survey during the course of one' year. It reflects the annual risk of being infected (or reinfected) in a given community. In other words, it expresses the attacking force of tuberculosis in a community. In developing countries, every 1 % of annual risk of infection is said to correspond to 50 new cases of smear-positive pulmonary tuberculosis, per year for 100,000 general population. Also known as "tuberculin conversion" index, this parameter is considered one of the best indicators for evaluating the tuberculosis problem and its trend. The higher the rate, the greater the problem . It may be mentioned that a good treatment programme, lowers the risk of tuberculosis infection in the community.