CDC Report - Hepatitis A Cases Among Food Handlers as All Those Infected with Hepatitis A

In a CDC report, investigators looked at the uptick of Hepatitis A in many states across the country.  Those regarded as high risk is where "infections are spreading primarily through close contact among persons who use drugs and persons experiencing homelessness, as well as among men who have sex with men (MSM)"  Of interest in the report was the percentage of food handlers, and overall, the percentage of cases associated with food handlers was low (3.8%).  Looking at food handlers, a high percentage of them were people in the high risk - people use drugs, have unstable housing or are homeless, are active in MSM, or had been incarcerated.

From the report, "Among 22,825 hepatitis A outbreak cases reported from these 26 states during July 1, 2016–September 13, 2019, 871 (3.8%) were among food handlers; 587 (67.4%) hepatitis A–infected food handlers reported one or more risk factors (i.e., drug use, unstable housing or homelessness, MSM, or incarceration) during the 15–50 days before symptom onset. "

https://www.cdc.gov/mmwr/volumes/69/wr/mm6920a4.htm
Notes from the Field: Assessing the Role of Food Handlers in Hepatitis A Virus Transmission — Multiple States, 2016–2019
Weekly / May 22, 2020 / 69(20);636–637
Megan G. Hofmeister, MD1; Monique A. Foster, MD1; Martha P. Montgomery, MD1; Neil Gupta, MD1 (View author affiliations)

The United States is experiencing person-to-person outbreaks of hepatitis A in unprecedented numbers during the vaccine era (1). As of May 2020, 33 states had reported hepatitis A outbreaks involving approximately 32,500 cases, 19,800 (61%) hospitalizations, and 320 deaths since 2016 (1). These infections are spreading primarily through close contact among persons who use drugs and persons experiencing homelessness, as well as among men who have sex with men (MSM) (2).

During these outbreaks, hepatitis A infections occurring among food handlers have raised public alarm and resulted in calls for vaccinating all food handlers, often prompting health departments to divert limited resources away from populations at risk. However, the risk for secondary transmission from hepatitis A–infected food handlers to food establishment patrons is not well understood. To characterize this risk, a novel, structured survey was developed and conducted using Research Electronic Data Capture (REDCap) (version 9.5.13; Vanderbilt University); among 30 state health departments reporting person-to-person hepatitis A outbreaks during July 1, 2016–September 13, 2019, 29 states responded (3,4).

Twenty-six states (89.7%) submitted complete information regarding secondary transmission events associated with food handlers (Table). Among 22,825 hepatitis A outbreak cases reported from these 26 states during July 1, 2016–September 13, 2019, 871 (3.8%) were among food handlers; 587 (67.4%) hepatitis A–infected food handlers reported one or more risk factors (i.e., drug use, unstable housing or homelessness, MSM, or incarceration) during the 15–50 days before symptom onset. Associated with these 871 hepatitis A–infected food handlers were eight (0.9%) secondary transmission events (Table), which resulted in 57 secondary cases.

Eighteen of 29 states (62.1%) submitted complete information for public health response activities related to hepatitis A–infected food handlers. Among 275 cases in food handlers from these 18 states, 271 (98.5%) investigations and 63 (22.9%) public notifications took place.

Ongoing hepatitis A outbreaks have been prolonged and costly to control (5). These study findings indicate that the risk for secondary infection from hepatitis A–infected food handlers to food establishment patrons in these outbreaks is low (<1.0%). Therefore, public health efforts to preemptively vaccinate all food handlers would be ineffective at mitigating the current risk for person-to-person outbreaks. To optimize resources, health departments should assess the risk for secondary transmission of hepatitis A from infected food handlers on a case-by-case basis and prioritize vaccination efforts in situations where secondary transmission risk is deemed high (6).

Approximately two thirds of the hepatitis A–infected food handlers in this survey reported risk factors commonly associated with the current person-to-person outbreaks. This underscores the importance of vaccination strategies targeting the populations at highest risk (i.e., persons who use drugs, persons experiencing unstable housing or homelessness, MSM, and persons who are or were recently incarcerated) as the cornerstone of an effective public health response.