The UK Health Security Agency (UKHSA) is looking into an increase in hepatitis A cases.

UKHSA and other health agencies are investigating two clusters of hepatitis A virus (HAV) with dozens of confirmed patients.

In the first, 31 people are sick with 23 in England, seven in Scotland, and one in Northern Ireland. Some are secondary infections. Cases have been reported across England in regions such as the South West, East, West Midlands, and London.

Sample dates range from January 2021 to March 1, 2025, but 23 cases have been recorded since August 2024. Nineteen people have been hospitalized but no deaths have been reported.

There are 15 women and 16 men sick. They have an age range of 5 to 80 with a median of 50 years old. The most affected group is people aged 50 to 69.

Analysis of patient questionnaires suggests a foodborne source. A food item from an unnamed supermarket is suspected as a possible vehicle of transmission because of its frequently reported consumption.

Epidemiological and virological investigations are ongoing with Public Health Scotland leading the incident management team. The Food Standards Agency (FSA) is also involved in the efforts.

Second cluster
In the second cluster, 64 people are ill with 57 in England, four in Northern Ireland, and three in Scotland.

Sample dates range from January 2023 to March 2025, but 53 cases have been seen since December 2024. only seven people recorded international travel in the 50 days before symptom onset.

In total, 37 women and 27 men are sick. Cases have an age range of 3 to 80 with a median of 32 years old. No deaths have been recorded but 39 people have been hospitalized.

Analysis of patient questionnaires identified multiple food categories of interest, which led to the FSA being alerted.

Hepatitis A virus is acquired through fecal-oral transmission and most commonly occurs in people who have recently visited countries wher the disease is more common. Outbreaks linked to food items from HAV endemic countries are more frequent at the start of the year.

The UKHSA said given the lack of international travel in most cases, and mention of implicated food items, further investigations into possible sources of the illnesses are continuing to help inform control measures.