The rate of adverse events following BCG vaccination in Poland

The purpose of the study was to evaluate the capacity of the surveillance system to respond to the schedule changes in the view of TB vaccination uptake. Complications of Bacillus Calmette-Guerin (BCG) vaccination in Poland are as elsewhere uncommon. In Poland, BCG vaccination with a vaccine produced with Mycobacterium bovis BCG Moreau has been a part of the National Immunization Program since 1955. In the beginning the immunization schedule involved several BCG revaccinations in children and youths, with the first dose given to neonates up to 1 month old followed by revaccinations at 2, 4, 7, 12, 15, and 18 years of life. In 90s, the number of BCG doses was reduced and since 2006, according to recommendations made by the WHO, a single BCG dose is given to neonates only.

In the study we have analyzed data on adverse events following BCG vaccination registered within a period of 1994-2010, with attention to the periods before and after 2006, when different BCG vaccination schedules were used for immunization.

The frequency of adverse events following BCG vaccination in Poland oscillated within 1994-2000 and 2001-2010 periods around 0.2 per thousand and 0.6 per thousand respectively, and in half consisted of local lesions at the injection sites and in half--appeared in the form of the regional lymphadenopathy. The analysis of surveillance data revealed similar rates of adverse events following BCG vaccination in the periods of different BCG vaccination schedules, eg. before and after 2006.

Improvements in the data collecting manner from passive to active one and the introduction of the routine laboratory confirmation of the infection might evaluate the real prevalence of Mycobacterium bovis BCG infections and improve the treatment of adverse events following BCG vaccination cases.