• Hepatitis E virus regularly found in uncooked sausages and other pork products in UK

Food safety experts have warned for many years that the Hepatitis E virus is a public health threat which has largely been ignored whilst more prescient viruses, bacteria and other bugs dominate the food chain. Not that long ago in 2014, ‘infection’ from sausages in England and Wales with what was then reported as one in ten of them containing this pernicious virus were reported in the media. It seems that in 2017 the issue still persists. Recent evidence suggests that imported sausages and probably other pork products as well from Europe and from piggeries in The Netherlands and Germany in particular were entering the food chain.

Hepatitis E or HEV G3-2 as it’s often referred to is fortunately killed by cooking for 20 minutes at or above 70°C at the centre of the product. That’s a typical and thorough cooking time for destroying most food pathogens including viruses.

The virus in the body causes liver damage such as cirrhosis and can be fatal. Jaundice with tiredness, nausea, vomiting, fever and abdominal or intestinal pain are common symptoms although other viral infections have these effects too. Not all symptoms are evident. Indeed, there may be a variety of strains as alluded to in a survey describing the virus in Clinical Infectious Diseases (Hughes et al., 2010) which defines four so far. The virus has been a common enough disease issue mainly in Africa and Asia (Kamar et al., 2014).

The number of confirmed cases of Hepatitis E infection in England and Wales according to Public Health England (PHE) has risen steadily from 124 in 2003 through to 691 cases in 2013 and still continuing upwards. The recent PHE report puts the level of infection of people in Britain at between 150,000 and 200,000 a year from 2014 onwards although that statistical range probably should cover all other sources as well. The NHS Blood and Transport departments are now screening all donated blood, organs and tissues for this virus.

Food Chain Issues

Hepatitis E usually enters the food chain from pig herds although is has been found in shellfish, poorly sanitised washing water and drinking water. Pig herds are perhaps most susceptible because the animal can readily be infected by eating other contaminated animal products and living in poor hygienic conditions. In the most recent case, Dutch scientists believe the virus is spread in slaughtered pigs’ blood which is collected and added back into meat after processing but not sterilised properly. Foods like black pudding and white pudding would also be susceptible to this.

Contaminated water is perhaps the biggest source of the virus. In 2012, 12 people died and 4,089 others became unwell after drinking water in the Indian state of Maharashtra. It was most likely contaminated sewage and faeces entering the Panchganga river which was then drunk further downstream.

Pork products are traded throughout the world and processed into a variety of foods including sausages, hams, pate, pork pies and kebabs. Sausages in particular are sources of infection in the sense that they are only cooked at the point of eating. More accurately, the risk of eating a contaminated sausage is 1 in 100 given the size of the sample of sausages tested. No doubt, a much wider survey is being conducted to establish the level of contamination.

One of the best sources of information about the virus is the British Liver Trust (see webpage).

References

Hughes, J. M., Wilson, M. E., Teshale, E. H., Hu, D. J., & Holmberg, S. D. (2010). The two faces of hepatitis E virus. Clinical Infectious Diseases, 51(3), pp. 328-334

Kamar, N., Dalton, H. R., Abravanel, F., & Izopet, J. (2014). Hepatitis E virus infection. Clinical Microbiology Reviews, 27(1), pp. 116-138.