Hepatitis A —Investigation and control of outbreaks in two primary schools

Outbreaks of hepatitis A in two primary schools in different parts of a city were investigated using similar methods. The pattern of each outbreak indicated that caseto-case transmission was likely. In both schools more boys than girls were affected. In one school, infection was commoner in those who brought packed lunches to school (10/86) compared with those who took school dinners or went home for lunch (3/88), although this was not statistically significant. Simple measures, such as attention to personal hygiene and exclusion of sick children from school, appeared to control the outbreaks. School-based transmission of hepatitis A in 5–14 year olds may be more important than the literature suggests, and may partly explain the high incidence in this age group.