Mass screening of tuberculosis among Filipinos by the Heaf test and its comparison with the Mantoux test

ABSTRACT

1. In 1962 and 1963 a study was conducted by the authors to determine the usefulness and practicality of the Heaf test for mass screening of tuberculosis2. The study group consisted of children and adults attending 7 public and 2 private schools and institutions in Manila and Quezon City as well as in towns and barrios in the provinces of Cavite, Laguna, Marinduque, Rizal and Bulacan. A total of 7,920 individuals were tested3. The Heaf test was positive in 24.2% of 7,920 children and adults tested4. Reactors to the Heaf test vary in different localities thus in cities these reached, 22% in towns 27% and in barrios 21%5. The reactor group was found to increase proportionately with icreasing age, which is the usual finding in almost any tuberculin survey by any test used6. In this study, we observed the equivalent of reactions for Heaf and Mantoux tests. Thus, a reaction of 1 to 6 papules to Heaf test is the equivalent of a "soft","erythema" or an induration of less than 10 millimeters by Mantoux which is the accepted positive reaction in the Philippines, has a corresponding 10 mm. induration by Heaf7. The two tests have a high percentage of agreement being 71.6% to 92% in 10 TU and 5 TU, (96%) in which the precentage of disagreement was 4%8, Taking into account the case and convenience of testing, a reasonable overall cost, and the finding of a high percentage of agreement with the standard Mantoux test, this study gives basis for recommending the Heaf test as a mass screening test for tuberculosis. (Summary)