Do Food Handlers Spread Hepatitis A to Diners? Evidence From the 2016–2019 Outbreaks

The U.S. has seen person-to-person hepatitis A outbreaks on a scale unprecedented in the vaccine era. By May 2020, 33 states had reported outbreaks since 2016, with about 32,500 cases, 19,800 (61%) hospitalizations and 320 deaths. The virus has spread mainly through close contact among people who use drugs, people experiencing homelessness, and men who have sex with men (MSM).

Infections among food handlers alarmed the public and prompted calls to vaccinate every food handler, often pulling health departments' limited resources away from the groups most at risk. But how often do infected food handlers actually pass the virus to diners?

The survey

CDC surveyed the 30 state health departments with person-to-person outbreaks from July 1, 2016, to September 13, 2019; 29 responded.

What they found

In the 26 states with complete data:

In 18 states with complete response data, 271 of 275 food handler cases (98.5%) were investigated; 63 (22.9%) led to public notification, and in 80 (29.1%), patrons were offered postexposure prophylaxis.

What it means

The risk of an infected food handler infecting patrons in these outbreaks was low — under 1%. So preemptively vaccinating all food handlers would do little to curb the person-to-person spread driving these outbreaks, which have been long and costly to control.

Instead, health departments should assess each infected food handler case by case, vaccinating where the risk of secondary spread is high. And since about two-thirds of infected food handlers had the same risk factors as everyone else in these outbreaks, the cornerstone of the response should be vaccinating the highest-risk groups: people who use drugs, people with unstable housing or homelessness, MSM, and people who are or were recently incarcerated.

Sources

Based on Hofmeister MG, Foster MA, Montgomery MP, Gupta N, "Notes from the Field: Assessing the Role of Food Handlers in Hepatitis A Virus Transmission — Multiple States, 2016–2019," MMWR volume 69, number 20, Centers for Disease Control and Prevention; a work of the United States government in the public domain.