Fourfold increase in norovirus prompts safety advice

A senior lecturer at the School of Biochemistry and Cell Biology at University College Cork (UCC) has shared advice on protection against the spread of norovirus.

It comes as the HSE’s Health Protection Surveillance Centre (HPSC) urged people to be aware of the symptoms of norovirus as cases increase in Ireland.

In the first 10 weeks of 2023, there were 394 cases of norovirus. This is four times the number of cases in the first 10 weeks of 2022 (109).

Young children and elderly people have been the most affected, with half of cases (50%) aged over 65 years and (28%) of cases aged under five years.

Dr Anne Moore, the senior lecturer, described the virus as a highly transmissible enteric virus.

“It is the most common cause of acute gastritis globally. Infection of the gut by this virus causes systems such as diarrhoea, vomiting, and so on.

“The young and the elderly can be more affected by this gastritis, compared to healthy adults. It’s estimated that there are about 700m cases annually, with about 219,000 deaths.

“It has a high economic burden; estimated to be about $60bn per year; related to healthcare costs and societal costs,” Dr Moore said.

Prevention against norovirus relies on basic hygiene and outbreaks have been related to contaminated food, nursing homes, and cruise ships.

“There are no anti-viral drugs to treat norovirus. There is quite a lot of work being conducted to develop a vaccine against norovirus. To protect against infection, this vaccine should induce immune responses in the gut. There are multiple strains of norovirus and known genetic susceptibilities to different strains,” she said.

Tips to prevent the spread of norovirus include frequent handwashing, cleaning and disinfecting of contaminated surfaces after an episode of illness by using a bleach-based household cleaner, removing and washing clothing or linens, and flushing or discarding any vomit and/or faeces in the toilet and making sure that the surrounding area is kept clean.

HPSC consultant in public health medicine, Dr Paul McKeown, said: “People who are ill with norovirus should stay at home and not go to work, or school, and they should not visit nursing homes or hospitals until 48 hours after their symptoms have gone.

“This is the best way to protect other, often vulnerable people.” Those who develop forceful vomiting are urged not to visit their GP without phoning ahead.”