Purified protein derivative (PPD) conversion rate among Lebanese children in Beirut.

To determine the purified protein derivative conversion rate among Lebanese children we followed a cohort of 1236 students, ages 5-14 years, enrolled in 25 public schools in Beirut. All cases received an intradermal injection of purified protein derivative in 1992 and one year later. Test administration was done using standard techniques and results were read by the same physician 48-72 hours later. Demographic information was also obtained on the enrolled students. The majority of children identified belonged to a low socioeconomic class. The one year conversion rate was 1.4%. This underscores the urgent need for preventive programs.