Norovirus lab reports climb 47% in 2 weeks

15 Jan 2026 04:48 PM

Weekly UKHSA report for the 2025/26 season, monitoring respiratory viruses.

This weekly bulletin brings together the latest surveillance data, along with the latest public health advice for flu, COVID-19, respiratory syncytial virus (RSV) and other viruses.

Latest

According to the latest surveillance data from the UK Health Security Agency (UKHSA), Norovirus cases have increased by 47% in the first 2 weeks of 2026, compared to the previous 2-week period ending 28 December, prompting a reminder about good hygiene measures to halt the spread of the virus.

Reports remain highest among those aged 65 years and over and although activity remains within expected levels, outbreaks in hospital settings are also rising.

UKHSA’s latest surveillance data also shows that flu, COVID-19 and RSV levels continued to decline in the first week of the year. While cases for all winter viruses remain within expected levels for this time of year, people are urged to continue taking simple steps to ensure this trend continues. Viruses like flu and norovirus can be unpredictable and trends can change throughout the season which is why it’s important that people take simple steps to reduce the spread.

For both respiratory and gastrointestinal viruses like norovirus, this includes washing hands regularly. Remember that alcohol gels do not kill norovirus, so regularly washing hands with soap and warm-water and using bleach-based products to clean surfaces will also help stop infections from spreading.

Making sure indoor spaces are well-ventilated can reduce the spread of respiratory infections like flu, and if you have symptoms, stay home where possible. If you need to go out, consider wearing a face covering particularly if visiting vulnerable people.

Amy Douglas, Lead Epidemiologist at UKHSA, said:

We have seen a notable increase in norovirus cases in recent weeks among those aged 65 years and over, with more hospital outbreaks also being reported. While this is still within expected levels, there are simple steps that people can take to reduce the spread of norovirus and ensure levels don’t rise further.

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.

If you have diarrhoea and vomiting, don’t 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. If you are unwell, avoid visiting people in hospitals and care homes to prevent passing on the infection to those most vulnerable.

Flu and RSV vaccines remain available. Those most at risk from flu are eligible for a free flu vaccine on the NHS, which includes everyone over 65, those who are pregnant, children from the age of 2 years (as of 31 August) to school year 11, and those with certain long-term health conditions. The RSV vaccine is also available to those aged 75 to 79, those who turned 80 years old after 1 September 2024 and is also offered to pregnant women at or beyond the 28-week mark, as the vaccine helps protect the newborn baby.

Vaccination helps provide the best protection against severe illness and hospitalisation for those at higher risk. Early flu vaccine effectiveness data from UKHSA shows that the flu vaccine is working well against the flu strain most dominant so far this year, so it’s important that those eligible still take up the offer and get vaccinated to ensure they are protected for the rest of the flu season.

Dr Alex Allen, Consultant Epidemiologist at UKHSA, said:

It’s encouraging to see that levels of flu and RSV have fallen for another week. But we mustn’t be complacent because our data from previous years tell us that the end of the flu season could still be some months away. Respiratory viruses are unpredictable but there are steps people can take to reduce the spread and ensure we continue on this downward trend – including taking up a vaccine if you haven’t yet.

Vaccine appointments are still available on the NHS national booking system and those most at risk who haven’t yet had their vaccine should make sure they take it up now to ensure they are protected for the remainder of the season. RSV vaccination remains open year-round for pregnant women and any older adults aged 75 to 80 who haven’t yet had a dose.

In the week between 5 January and 11 January 2026:

• Influenza activity decreased and is circulating at low levels
• COVID-19 activity remained stable and is circulating at baseline levels
• Respiratory syncytial virus (RSV) activity decreased slightly and is circulating at medium levels 

The flu, COVID-19 and RSV surveillance report and the national norovirus and rotavirus surveillance reports: 2025 to 2026 season are published weekly.

Norovirus surveillance data between week 1 to week 2 of 2026:

• norovirus activity has increased in recent weeks but remains within expected levels
• overall, norovirus laboratory reports between weeks 1 and 2 of 2026 (29 December 2025 to 11 January 2026) were 27.6% higher than the 5-season average for the same 2-week period and 46.5% higher than during the previous 2-weeks
• the rate of norovirus laboratory reports remains highest among individuals aged 65 years and over
• rotavirus activity between weeks 1 and week 2 of 2026 were 7.2% lower than the 5-season average for the same 2-week period
• the number of norovirus outbreaks reported to the Hospital Norovirus Outbreak Reporting System (HNORS) since the start of the 2025/2026 season is 44.8% lower than the 5-season average
• during the 2025/2026 season to date, the majority (84.3%) of samples characterised were norovirus genogroup 2 (GII), of which the most frequent genotype identified was GII.4 (32.8%), although GII.17 and GII.4 have continued to co-circulate
• norovirus symptoms include 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)

Flu surveillance data for week 2 (5 – 11 January 2026): 

• flu activity decreased and is circulating at low levels
• flu positivity decreased with a weekly mean positivity rate of 11.7% compared with 14.1% in the previous week
• overall, flu hospitalisations were decreasing at 5.37 per 100,000 compared with 7.20 per 100,000 in the previous week

For the 2025-26 season’s vaccination programme, children and pregnant women have been eligible since 1 September, with other groups eligible from 1 October.

Up to the end of week 2 of 2026 (11 January), vaccine uptake stands at:

• 74.1% in all those aged over 65 years
• 40.2% in those aged under 65 years with one or more long-term health conditions
• 38.2% in all pregnant women
• 43.1% in children aged 2 years and 44.3% in children aged 3 years

Respiratory Syncytial Virus (RSV) surveillance data for week 2 (5 – 11 January 2026): 

• RSV activity decreased slightly and is circulating at medium levels
• RSV positivity decreased slightly to 7.3% compared with 8.6% in the previous week
• the overall weekly hospital admission rate for RSV was decreasing slightly at 2.99 per 100,000 compared with 3.31 per 100,000 in the previous week
• emergency department attendances for acute bronchiolitis decreased

COVID-19 surveillance data for week 2 (5 – 11 January 2026): 

• COVID-19 activity remained stable and is at baseline levels
• COVID-19 positivity remained stable with a weekly mean positivity rate of 1.6% compared with 1.6% in the previous week
• COVID-19 hospitalisations were slightly decreasing at 0.81 per 100,000 compared with 0.90 per 100,000 in the previous week
• COVID-19 ICU admissions remained low at 0.03 per 100,000 compared with 0.03 per 100,000 in the previous week