British doctors have urged authorities to make flu testing available amid concerns that an influenza epidemic may be about to collide with a third wave of Covid-19.
In a report published Thursday, physicians from the U.K.'s Academy of Medical Sciences warned a resurgence of respiratory viruses such as flu and RSV — a common virus that can be serious for young infants and the elderly — was likely to increase pressure on the country's National Health Service.
The U.K. is due to lift nearly all Covid restrictions on July 19. However, the country is currently experiencing a rise in new cases of the virus, which has been linked to the highly transmissible delta variant.
On July 14, 42,302 people tested positive for Covid in the U.K., making it the country with the fourth-highest number of new cases, according to Johns Hopkins University.
Doctors warned in Thursday's report that overlapping symptoms between flu and Covid meant routine testing for both viruses, and possibly additional respiratory infections — known as multiplex testing — would be important ahead of an expected uptick in common winter illnesses. Medical experts have expressed concerns the U.K. could be headed for an influenza epidemic later this year, and multiplex testing would help doctors differentiate between viruses, allow them to monitor the growth of epidemics, make timely decisions about treatments and reduce transmission rates, the report said.
"We strongly support multiplex testing," its authors said. "However, if this is not feasible, well evaluated and accurate point-of-care testing for influenza should be deployed in hospitals, primary care settings, care homes and community pharmacies."
They added that "the symptoms of influenza and other winter respiratory viruses are typically clinically indistinguishable from Covid-19 without a test," and warned demand for PCR tests may surge this year given the potential rise in winter diseases with similar symptoms.
A recent study of Covid symptoms in the U.K. found that the most common symptoms of the virus included a headache, sore throat and loss of smell. However, these can vary and people with the virus can also experience flu-like symptoms such as fever and a cough, according to the U.S. Centers for Disease Control and Prevention and the U.K.'s NHS.
The AMS noted that while a successful vaccine rollout would mean mortality would be lower in the next wave than in the winter of 2020/2021, continuous transmission of Covid among the under-50s could result in higher levels of "long Covid" than seen in the previous two waves. The medical body also warned that if Covid cases rise or remain elevated throughout the fall and winter, the third wave could coincide with a resurgence of flu and RSV, adding pressure to the NHS.
Outbreaks of RSV and flu during the fall and winter may be twice as large as the numbers seen in a "normal" year, according to the report. Social distancing and lockdown measures had prevented these illnesses from spreading at their usual rates during the coronavirus pandemic, meaning population immunity may have been diminished.
"Very low levels of influenza over the last two seasons will have led to lower levels of immunity than usually seen, which means a wave of influenza could be problematic," the report warned. A priority should be to ensure vulnerable groups were given a flu vaccine, its authors said, although flu vaccines were less effective than those for Covid.
Around 10,000 deaths are caused by flu in a regular year in England and Wales, according to the NHS.
Meanwhile, non-infectious illnesses like asthma and stroke were also likely to be exacerbated in the winter, the AMS report warned, adding more pressure to health care services.