Study of diphtheria antibody levels in healthy population.

Diphtheria antibody levels were analysed in 200 healthy individuals by Indirect Haemagglutination test. The antibody titres in the age groups 1-5 and 6-10 years were well above the protective level. The titre declined with increase in age. In 11-20 years of age about 17.5 per cent, in 21-30 years of age 52.5 per cent and in persons above 30 years of age 82.5 per cent people had antibodies below protective level. Our results are comparable to studies from India and abroad. Emphasis is given for reconsideration of immunisation programme in higher age group.