Hepatitis A case reported in Monterey, California

The recent report of a food handler with hepatitis A again highlights the importance of hepatitis A vaccination for those involved in food catering. It is also important for travellers who are very dependent on food handlers to provide food and drinks safely.

According to news reports, public health officials are investigating an employee who became ill while working at a well-known restaurant in Monterey, California. They are now having to follow up all people who attended the restaurant between the 13th and 22nd of November 2024.

Understanding Hepatitis A transmission and risks

Hepatitis A is transmitted through contaminated food and fluids. No further cases have been identified to date, but the disease has an incubation period of 3 to 6 weeks. Further cases might be expected but vaccination within 2 weeks of exposure has been found to lessen the impact of the disease.

Hepatitis A is not a benign disease. While it is generally accepted that it might go unnoticed in very young children, it does have a mortality rate in older individuals. Convalescence after a bout of hepatitis A can also be prolonged.

A “growing up disease” in some regions

Hepatitis A is a common “growing up disease” in many low and low middle-income countries where public health infrastructure is poor. The child develops his/her immunity early in life and maintains this immunity over a lifetime, much in the same way as most individuals born before the 1960’s in Australia became naturally immune to chickenpox, measles, mumps and rubella.

Natural immunity to hepatitis A would not be common in those growing up in countries with a well-developed public health infrastructure.

Vaccination has been available in Australia since the 1990’s.

Over 200 cases of hepatitis A have been notified in Australia in the past 12 months (10 November 2024). It is likely many are related to travel.

Challenges of tracking Hepatitis A exposure

In October 2023, a food handler working in the precinct of Edmonton International Airport, Canada, was diagnosed with hepatitis A. Imagine how difficult it would have been to follow up those people who might have been exposed at the café.