[An epidemiologic assessment of viral hepatitis type A morbidity in the Gdansk province in the years 1989-1990]. / Próba oceny epidemiologicznej wzrostu zachorowan na wzw A na terenie województwa gdanskiego w latach 1989-1990.

The considerable increase in viral hepatitis type A morbidity was observed in 1989-1990 in the area of Gdansk province. That increase was clearly focusing, it concerned only the chosen towns and communities. In these areas and also in regions where the increase in morbidity did not take place, the special researches have been carried out among children and adults which determined the frequency of passed HAV infection. It has been tried to investigate the ways and to describe the reasons of epidemic enlargement. It was proved that in adults group, the difference of the passed infection HAV frequency was not significant statistically comparing to the towns and villages dwellers, either for the regions where epidemic took place or without it. Comparison of the examined children revealed statistically the essential differences between the towns and villages-dwellers and significantly higher anti-HAV frequency among the children from the areas with morbidity increase. For explanation of the epidemic enlargement ways, the fast spreading of infection was emphasised on the areas situated at Wierzyca river and all its tributary streams.