Studies on antibody to hepatitis A virus in children and adults in London.

366 specimens of serum from children and adults without liver disease were screened for antibody to hepatitis A virus (anti-HAV) by means of radioimmunoassay. 56% were born in London, 26% came to London from various parts of the United Kingdom and the remainder (18%) from various parts of the world. The prevalence of antibody was related to increasing age, ranging from 7% in children under ten years of age to 77% in adults aged 50 years or more. The prevalence of anti-HAV was significantly higher in females, in the lower socio-economic class and in those not indigenous to London. In comparison to other urban populations such as those of the United States and Western Europe, the prevalence of anti-HAV was similar in terms of the overall prevalence and age distribution. By contrast, these findings were entirely different from the countries of Eastern Europe and the Middle East where the overall prevalence was higher but the anti-HAV was equal in all ages. Thus, the findings presented indicate that hepatitis A virus infection is common in London and also shows a clear relationship to advancing age, lower socioeconomic class and the country of origin.