There are three serious viruses going round Britain – which one have you got?

How dangerous are these viruses and how long does infection last?

While rhinoviruses are less deadly, they can still cause problems for anyone with underlying lung problems such as chronic bronchitis from air pollution or heavy smoking. “Even the common cold can kill occasionally,” says Prof Hunter. “Most of the time, that’s much less common than it is with flu which can cause problems even in otherwise reasonably healthy people.”

One of the problems with both flu and Covid is that they attach to receptors on cells in the lower airways, making them more likely to cause viral pneumonia. Prof Hunter believes that flu is actually now more virulent in this regard than Covid.

But one of the biggest dangers, and something that may be contributing to the current burden of persistent illness, is co-infections where unwell individuals become infected with more than one virus or pathogen at a time. Studies have shown that people can be infected with both flu and Covid, while flu can enable severe bacterial co-infections due to the damage it inflicts on your lung tissue.

“Flu damages the cells in the respiratory tract that help you clear the bad bugs out of your lungs,” says Prof Hunter. “So sometimes you might get over your acute illness, and then a week or so later you develop this very severe pneumonia which kills people. A lot of deaths after the flu each year are not actually caused by flu.”

However, Dr Al-Zubaidi says that in most cases any of these viral infections should clear up within a week. He suspects that one of the reasons people are unwell for longer periods is due to the growing numbers of long-term health conditions in the population, along with the prevalence of obesity, which impacts on immunity.

“These infections aren’t getting more severe,” he says. “We are just more unwell with background conditions that reduce our ability to fight off these kinds of infections.”

How should you treat these infections?

Because these are viral infections, antibiotics are not effective and you shouldn’t expect them. Instead, Dr Tukmachi says that GPs will initially suggest lifestyle measures such as taking multivitamin or zinc supplements to try to boost the immune system. Other doctors, such as GP Dr Semiya Aziz, also recommend getting plenty of rest, avoiding caffeine as this can dehydrate you, and using a humidifier and keeping rooms well ventilated through opening doors and windows, to help relieve cough symptoms. “Avoid lying on your back, which can make coughing worse,” she says. “Lie on your side or sit upright instead.”