The Health Protection Surveillance Center in Ireland has issued a warning about hepatitis E and undercooked pork following an increase in the number of people infected during summer and autumn this past year.

The agency reported a small increase in clinical notifications during the summer and autumn periods in 2018.

Health Protection Surveillance Center (HPSC) officials reminded consumers of the risk associated with undercooked meat, particularly when barbecuing. Meat cooked on a grill is more likely to char on the outside, while remaining undercooked in the middle.

FSAI advice

Hepatitis E infection is a disease of the liver caused by hepatitis E virus (HEV). Infections have been linked to consumption of raw or undercooked pork or game meat but can also occur through drinking HEV contaminated water or eating contaminated shellfish.

The Food Safety Authority of Ireland (FSAI) recommends cooking pork and pork products such as sausages to a minimum temperature of 75 degrees Celsius at the center of the thickest part.

The agency recommends use of a meat thermometer to check temperature of cooked meat and meat products. Hand washing and hygiene precautions in the kitchen are also essential to prevent foodborne illness through handling of raw meat or cross contamination of cooked food by raw items, utensils and food contact surfaces

The average time between exposure to the hepatitis E virus and infection is 40 days with a range of 21 to 56 days. Half of infected people do not develop symptoms but can still spread the virus to other people.

Symptoms may include yellowing of the skin and eyes, dark urine, extreme fatigue, nausea, vomiting and abdominal pain and can be more severe in pregnant women and people with weak immune systems.

Role of food

Hepatitis E became a notifiable disease in Ireland at the end of 2015. There were 218 notifications to HPSC between 2016 and 2018. A total of 66 percent were clinical cases, detected because they had clinical symptoms, or liver function test results, consistent with viral hepatitis while the other 34 percent were blood donors.

There were 54 notifications of hepatitis E in 2017 compared to 90 in 2016. Food histories were completed for 23 cases of HEV.

All but one had eaten one or more pork products in the nine weeks before illness or diagnosis. The one case who had not consumed pork was likely infected outside Ireland. The most commonly eaten pork items were bacon at 91 percent, pork sausages at 87 percent, pork meat at 74 percent, and sliced ham.

In 2017, the European Food Safety Authority (EFSA) found consumption of raw or undercooked pork meat and liver was the top cause of hepatitis E infection in the EU.

According to data from the European Centre for Disease Prevention and Control (ECDC), the number of confirmed HEV cases has skyrocketed from 514 in 2005 to 5,617 cases in 2015, representing a 10-fold increase. A total of 28 deaths were reported from five countries between 2005 and 2015.