The 'Two-Bucket' Virus: A Winter Woe with a Spring Twist
Imagine a virus that causes both vomiting and diarrhoea, a double whammy that has hospitals on high alert. This is the reality of the norovirus, a highly contagious bug that's causing a surge in cases, even as we approach spring. But here's where it gets controversial: experts are puzzled as to why this virus is thriving when other respiratory illnesses are on the decline.
Norovirus, often dubbed the 'winter vomiting bug,' has seen a significant rise in cases, with the latest NHS England figures revealing a daily average of over 1,000 patients in hospital with the virus - a 10% increase from the previous week. This is the second consecutive week of rising figures, leaving health officials scratching their heads.
'The reason for this surge is not entirely clear,' says Professor Andrew Easton, a virologist at the University of Warwick. 'While respiratory viruses like Covid-19, RSV, and the flu are declining, norovirus is going against the grain.'
Symptoms of norovirus include nausea, vomiting, diarrhoea, high temperature, abdominal pain, and aching limbs. The virus has an incubation period of several days, meaning people often don't realize they're carriers until after they've spread it to others. This stealthy nature has led to hospital wards being closed to contain outbreaks.
The problem with norovirus is its extreme infectiousness. It takes less than 100 particles to make someone sick, and infected individuals shed billions of these particles in their stools and vomit. With other infections still circulating, such as flu and Covid, health services are at risk of being overwhelmed.
One theory suggests that multiple mutations of norovirus are in play, with people recovering from one variant only to catch another soon after. Research published in Nature Communications supports this, showing a surge in infections caused by genotype GII.17, which mutates quickly, allowing it to infect people multiple times. Meanwhile, strains of the GII.4 genotype, responsible for 70-80% of outbreaks between 2006 and 2016, are still around, meaning those who've had norovirus this season can catch it again.
Professor Easton explains, 'Our immune system is great at identifying targets, but if the target changes, immunity against new variants may be weaker.' He adds, 'With multiple genotypes, reinfection in the same season is possible, as seen with RSV and norovirus.'
The persistent wet weather in the UK has also kept people indoors, making it easier for the virus to spread. Other infections are circulating too, and recovering from one virus can leave you vulnerable to another.
A 2022 study in The Lancet found that nearly 7,000 hospital patients with Covid also had flu, RSV, or adenoviruses, or a combination. 'Developing one virus can reduce your immune defenses against others, leading to more severe outcomes,' says Professor Peter Openshaw, a respiratory physician at Imperial College London.
One of the best ways to protect yourself is to ensure good ventilation in your home and office. 'Norovirus spreads through oral and faecal contact, but also in aerosol droplets, especially if someone is vomiting near others,' explains Professor Openshaw. Poorly ventilated rooms can increase the risk of spread, especially with many infected people.
The risk of airborne transmission is higher when people in enclosed spaces are active, like exercising in a gym, or shouting, singing, or talking loudly. 'Opening windows for short bursts throughout the day can improve air quality and reduce virus levels,' he adds.
Professor Easton believes the Covid-19 lockdowns may have contributed to lowered immunity, with people isolating and wearing masks, reducing exposure to flu and other respiratory infections. 'There's a possibility that over two years of reduced exposure, there's a general decrease in immunity to these viruses.'
For those wanting to stay healthy, it's not too late to get vaccinated. Appointments for the NHS flu jab run until March 31, 2026, and RSV vaccinations are available to certain vulnerable groups. A 2024 study in The Lancet showed the RSV jab was 72% effective at preventing infection.
While there's no norovirus vaccine, a high-fibre diet can boost your immune system, reducing your risk of illness. A study by the University of Cambridge found that eating more fibre supports the growth of good gut bacteria, reducing the risk of illnesses like pneumonia.
'We carry a population of bacteria in our bodies, and the nature of this microbiome is significant for our health and ability to fight infections,' explains Professor Easton.
If you do fall ill with a bug like norovirus, rest and isolate until symptoms pass. Pharmacist Sultan Dajani recommends paracetamol and co-codamol to reduce pain and fever without irritating the stomach. Ibuprofen is not recommended for regular or long-term use for those over 65 due to the risk of stomach ulcers.
Regular handwashing with soap and water is essential, as the virus spreads through contact. Replacing lost fluids is also crucial, as norovirus can lead to increased fluid loss, hindering the body's immune response. Mr. Dajani advises clear soups over spicy food and dairy, and to avoid alcohol and caffeine, which can increase fluid loss.
So, while the 'two-bucket' virus continues to cause concern, with the right precautions and a focus on immune health, we can navigate this challenging season.
