Transmission of Hepatitis A Virus Infection despite Vaccination

To the Editor: In 1989, a killed hepatitis A virus (HAV) vaccine produced from cell culture was described.1 Today, several vaccines are available commercially in countries all over the world. The World Health Organization and other advisory committees now recommend the use of these vaccines for prophylactic purposes as well as for intervention during epidemics.2 It is uncertain whether persons who are vaccinated after coming into contact with patients with hepatitis A can nevertheless become infected and possibly excrete infectious HAV without clinical symptoms, thus posing a risk to others. We describe the spread of symptomatic hepatitis A infection among . . .