The UK Health Security Agency (UKHSA) is warning that norovirus cases are increasing, with the potential for a “second wave.” Now, experts caution that even those who have already been infected could catch it again, according to GOV.UK.
Laboratory reports have now reached their highest levels since UKHSA began tracking cases this way in 2014. But with seasonal illnesses like colds and flu also circulating, how can you tell them apart?
What are the symptoms of the norovirus and flu?
Norovirus
Although it is often called the winter vomiting bug, you can get norovirus at any time of year. This viral stomach bug causes vomiting and diarrhoea. The UKHSA warns: “This season we are experiencing the highest number of norovirus cases since our current reporting system began.
“The main symptoms of norovirus are feeling sick (nausea), diarrhoea, and being sick (vomiting). You may also have a high temperature, headache, and aching arms and legs.”
In further warnings, the NHS notes that other symptoms of norovirus, which usually start suddenly, can include:
- tummy pain
- body aches and pains
- a high temperature
- a headache
Flu
According to the UK Health Security Agency, this is a viral infection which affects the nose, throat, and lungs. It is prevalent during the winter months and can cause a number of symptoms.
The NHS lists the following symptoms that could indicate you have the flu
- a headache
- feeling sick
- being sick
- a store throat
- difficulty sleeping
- a sudden high temperature
- an aching body
- feeling tired or exhausted
- a dry cough
- loss of appetite
- diarrhoea or tummy pain
What is the difference between the norovirus and flu?
Dr Richard Martinello, an infectious diseases expert and chief medical officer for Yale Medicine, told today.com that both viruses can cause gastrointestinal symptoms. However, they are often seen in people infected with norovirus and rarely appear with the flu.
Often norovirus symptoms are more severe with the doctor explaining if you have it you’ll likely have diarrhea that’s “frequent and very watery.” In addition to this, he notes that you may also find it hard to keep water down.
If you have the norovirus, you’ll likely not experience respiratory symptoms such as congestion and a cough according to Doctor Stuart Ray, a professor of medicine and oncology at Johns Hopkins University School of Medicine. Having a headache, sore throat and cough are symptoms that “differentiate norovirus from influenza,” Martinello adds.
UKHSA norovirus warning
Issued today (February 27), Amy Douglas, Lead Epidemiologist at UKHSA, warns: “Norovirus levels are still exceptionally high and now with multiple genotypes spreading at the same time, people could end up getting infected more than once this season.
“We are seeing the biggest impacts in health and social care settings, such as hospitals and care homes. “Symptoms of norovirus can be more severe in older adults, young children and those who are immunocompromised.
“If you have diarrhoea and vomiting, please do not visit hospitals and care homes or return to work, school or nursery until 48 hours after your symptoms have stopped and don’t prepare food for others, as you can still pass on the virus during this time.
“Alcohol gels do not kill norovirus. Wash your hands with soapy warm water and clean surfaces with bleach-based products where possible to help stop infections from spreading.”
The rise in norovirus cases this season is likely driven by the GII.17 genotype, as previous immunity to this strain is low. However, the rise in cases may also be influenced by UKHSA’s enhanced testing capabilities and shifts in infection patterns since the COVID-19 pandemic.