Weight fluctuations after immunization in a rural preschool child community.

After inoculations with diphtheria, pertussis, tetanus (DPT), smallpox Bacillus Calmette-Guèrin (BCG), polio, and DPT + polio vaccine preparations, weight-for-age fluctuations were monitored in over 470 rural preschool children and compared to those in nonvaccinated control children matched for age, weight-for-age, season and year of immunization, and village affiliation. It was found that children immunized with live agents (BCG, smallpox, polio, DPT + polio) who also were below 6 months of age suffered statistically significant reductions in their weight-for-age compared to matched nonimmunized controls. Children inoculated with polio or smallpox who also were below 80% of the Harvard weight-for-age median experienced a larger decrease in their nutritional levels than those above, with correction for age distribution. It is suggested that in the developing world immunizations with live agents to children below 6 months of age should be given only if the infectious illness in which immunization is provided poses a real threat to health, or if vaccination coverage of children above 6 months of age would subsequently be difficult to achieve.