True statement regarding "tuberculine test" is -
Used for diagnosis of TB
Measures incidence of disease
More than 10mm induration in 72 hrs. Indicates positive test
Measures immunity status
The tuberculin test is the only means of estimating the prevalence of infection in a population . Produce a pale wheal of the skin, 6 to 10 mm in diameter. The result of the test is read after48-98 hrs but 72 hrs(3rd day) is the ideal. Reaction exceeding 10 mm are considered positive. Ref:PARK&;S TEXTBOOK OF PREVENTIVE AND SOCIAL MEDICINE 23rd edition , Page 185
Communicable diseases