One dose of diphtheria, tetanus, and pertussis vaccine was associated with a mortality ratio of 1.84 (1.10 to 3.10) and two to three doses with a ratio of 1.38 (0.73 to 2.61) compared with children who had received no dose of these vaccines.”
Routine vaccinations and child survival: follow up study in Guinea Bissau, West Africa.
Kristensen I, Aaby P, Jensen H. British Medical Journal. 2000 Dec 9;321(7274):1435-8.
Research on vaccines in developing countries recommended by the World Health Organization has emphasised serological responses and protection against specific diseases. The aim of the research has been to optimise vaccine schedules for control, elimination, or eradication of disease. In modelling exercises, vaccination against diphtheria, pertussis, tetanus, and polio has been assumed to save 1.52.0% of the children in areas with high infant mortality. However, these assumptions are not supported by data. Mortality was lower in the group vaccinated with any vaccine compared with those not vaccinated, however, recipients of one dose of diphtheria, tetanus, and pertussis or polio vaccines had higher mortality than children who had received none of these vaccines.