General non-specific morbidity is reduced after vaccination within the third month of life--the Greifswald study.

OBJECTIVES

The incidence of many serious infectious diseases fundamentally decline as a success of consequent vaccination regimens. However, it is a matter of discussion if vaccination might cause unspecific negative side effects on the immune system. To answer this, we performed a clinical study on children with the question as to whether there is an enhanced frequency of infection diseases after vaccination or not.

METHODS

The study population (n=496) was randomized to a group of vaccinated children (first vaccination on the 60th day of life, n=201) and a group of unvaccinated children (first vaccination on the 90th day of life, n=295). Frequencies of unspecific, morbidity-related signs were recorded by the mothers with a diary card. These data were taken for further statistical analysis to determine if the factor "vaccination" does have a significant effect on the variable "morbidity".

RESULTS

Various infectious disease-associated symptoms (vomiting, coughing, signs of rhinitis, restlessness, rash and pain) were significantly less often seen in vaccinated than in non-vaccinated children.

CONCLUSIONS

Our study revealed that children who received vaccination against diphtheria, pertussis, tetanus, HiB and poliomyelitis simultaneously within the third month of life do not exhibit enhanced frequencies of infectious disease-associated symptoms. In contrary, the frequencies of infection-associated symptoms were found to be significantly reduced. This might be caused by a vaccination-associated unspecific enhancement of immunological activity (e.g. mediated by interleukin 2) or by other presently still unknown factors.