Health Protection Scotland has published annual surveillance reports for Listeria, hepatitis A and E, norovirus, Shigella and Yersinia.
Data shows a decline in Listeria, Shigella, Yersinia and norovirus cases while hepatitis A and E infections increased in the past year.
During 2019, there were six cases of Listeria monocytogenes reported to Health Protection Scotland (HPS), the lowest number seen in recent years. There were 12 cases reported in 2018 and 17 infections in 2017.
Surveillance of Listeria in Scotland relies on reports from all laboratories in the country. These are reported to HPS via Electronic Communication of Surveillance in Scotland (ECOSS).
Hepatitis A and E rise
In 2019, there were 50 cases of Hepatitis A reported to HPS. This was higher than the 34 reports in 2018. In 2017, there were 153 cases but 91 of these were associated with a foodborne outbreak of Hepatitis A in Lanarkshire.
Hepatitis A is an infection of the liver caused by the hepatitis A virus. Foodborne outbreaks have been associated with contamination of ready to eat foods by infected food handlers. Outbreaks have also been linked to contamination further upstream in the food production process including shellfish and fresh and frozen berries.
Reports of hepatitis E virus (HEV) infection in Scotland and elsewhere in the United Kingdom have gone up in recent years. Lab reports of HEV in Scotland rose from 13 in 2011 to 226 in 2016. It is likely that more clinical recognition and testing of hepatitis E has contributed to the rise since 2011, according to HPS.
In 2019, HPS received 158 reports of HEV, an increase of 41 percent on the 112 reports in 2018 but still less than the 171 in 2017.
HPS is working with Food Standards Scotland, the Scottish Government, NHS boards and Public Health England to improve understanding of the epidemiology of HEV, including risk factors and exposures that will inform public health management and control.
Hepatitis E is an illness of the liver caused by the hepatitis E virus, which can infect animals and humans. HEV infection usually produces a mild disease. However, symptoms can vary from no clear symptoms to liver failure.
Norovirus, Shigella and Yersinia decline
During 2019, HPS received 890 laboratory reports of norovirus. This was a decrease of around 40 percent on the 1,491 lab reports in 2018 and was the lowest number in recent years. Norovirus is a common cause of infectious gastroenteritis that results in diarrhea and vomiting. It is very easily spread from one person to another and through food.
Laboratory reports of norovirus show a seasonal trend, with most during winter months. Predominantly the elderly and young were affected with 437 of 890 reports from those aged 65 years and over and 238 from those under five years old. This probably reflects those from whom samples are most likely to be taken, according to HPS.
In 2019, there were 101 reports of Shigella in Scotland which was a slight drop from 115 in 2018. Of the 98 isolates further speciated, Shigella sonnei was the most common with 68 cases, down from 77 in 2018.
There were 25 cases of Shigella flexneri in 2019 which was a slight decline from the 32 reported in 2018. Four cases of Shigella boydii and one of Shigella dysenteriae were also reported in 2019.
Yersinia infections are not common in Scotland. In 2019, there were five reports of Yersinia enterocolitica. This was a fall from the 12 in 2018 and 2017 and nine in 2016.
(To sign up for a free subscription to Food Safety News, click here.)