An urgent warning has been issued by the UK’s health authority to stop the spread of a contagious virus of which cases are currently “exceptionally high”. The UK Health Security Agency (UKHSA) released the latest data on norovirus on Thursday afternoon.
It also gave an update on flu, Covid and Respiratory Syncytial Virus (RSV) levels. It said flu levels decreased to “medium” activity, while Covid was “stable” over the past week. RSV levels fell as well.
However, when it came to sickness and diarrhoea bug norovirus, the news was not so good. The UKHSA said norovirus reports in the two-week period between January 20 and February 2 were 17.4% higher than the previous two-week period. The total number of reports was 116.7% higher than the five-season average for the same two-week period. Laboratory reporting remained highest in adults aged 65 years and over, it added. The UKHSA also said that hospital outbreaks were currently 22.6% higher than the five-season average.
It explained: “While some of the increased reporting may be attributable to the increased use of PCR multiplex technology (capable of detecting multiple gastrointestinal pathogens in one test), it is likely that the emergence of an unusual norovirus genotype, GII.17, as well as changes in the epidemiology following the COVID-19 pandemic and other factors are contributing to the observed rise.
“During the 2024/2025 season to date, the majority (91.3%) of samples characterised were norovirus genogroup 2 (GII), of which the most frequently identified genotype was GII.17 (54.7%), an increase of this genotype has also been observed in other counties during 2024 and is being closely monitored — at present there is no indication it leads to more severe illness.”

Norovirus symptoms and what to do if you catch it
The UKHSA said norovirus symptoms included nausea, vomiting and diarrhoea, but can also include a high temperature, abdominal pain and aching limbs. Norovirus infections can cause dehydration, especially in vulnerable groups such as young children and older or immunocompromised people, so if you do get ill it is important to drink plenty of fluids during that time.
Dr Gauri Godbole, deputy director at UKHSA, said: “Norovirus cases are still exceptionally high and continue to rise. Half term usually provides a bit of a firebreak, so hopefully we will see a fall in numbers in the next few weeks. However, it’s really important that if you have diarrhoea and vomiting, you take steps to avoid passing the infection on. Please avoid visiting people in hospitals and care homes to prevent passing on the infection in these settings.
“Do not return to work, school or nursery until 48 hours after your symptoms have stopped and don’t prepare food for others in that time either. This is because you can still pass on the virus in the days after you stop being sick.
“Washing your hands with soap and warm water and using bleach-based products to clean surfaces will also help stop infections from spreading. Alcohol gels do not kill norovirus so don’t rely on these alone.”