Vaccination strategies for control of community outbreaks of hepatitis A: A comparison of two outbreaks in England

In August 2015 two community outbreaks of hepatitis A virus (HAV) occurred in sub-urban communities in Northern England. Each was managed by an independent outbreak control team. In outbreak one, mass vaccination was deployed targeting a residential area and two schools, while in outbreak two, vaccination was reserved for household-type contacts of cases. The highest vaccination uptake was achieved in the school settings (82% and 95%). These case studies illustrate the range of approaches that can be used and the factors that influence decision-making in response to a hepatitis A community outbreak. Both outbreaks likely started from importation(s) of HAV by returning travellers and spread through extended social networks and the local community. Vaccination strategies were selected based on hypotheses about transmission pathways, which were informed by evidence from oral fluid (OF) testing of asymptomatic contacts. More evidence about the effectiveness of mass vaccination in community outbreaks of hepatitis A in low endemicity settings is needed. Hepatitis A guidelines should include recommendations for the use of mass vaccination and OF testing in outbreaks.