K. K. Datta

Epidemiological Considerations of the Age Distribution of Measles in India: a Review

This paper reviews the Indian data on age distribution of measles prior to large scale immunization. In metropolitan areas, the median age was about 24 months and virtually all the cases were recorded in children under 5, whereas median age in most of rural studies was < 4-< 5 years and all the persons were not affected until 10 years of age. The situation was in between in other areas. Since less than 10 per cent of the cases occurred before 9 months of age, this age is appropriate for routine measles immunization. The results also suggested the choice of age groups to be immunized during measles mass campaigns; the upper age may be 3 years in metropolitan city, 10 years in rural areas, and 5 years in the rest of the population.

Transplacental Dilution of Tetanus Antitoxins in Delhi

Maternal blood-cord samples from 171 women of middle socio-economic status who had been administered at least two doses of tetanus toxoid (TT), were assayed for tetanus antitoxins by passive haemagglutination (PHA) test. All the mother as well as cord samples had antitoxin titres > or = 0.015IU/ml, the generally accepted minimal protective level; 98 per cent of the mothers and 97 per cent of the newborns had levels > or = 0.125IU/ml. Transplacental dilution was observed in 45 per cent of the samples; the cord/maternal antitoxin ratio (C/M) of geometric mean titre (GMT) was found to be 0.72. The C/M ratio was not affected by the maternal age, parity, birth weight, and number of TT doses administered to mother. The study showed that tetanus antitoxins were diluted on the fetal side of circulation, but the protective levels of antitoxins were achieved in all the newborns as the mothers had received at least two doses of TT before delivery.