Doctor reveals why so many people in the UK feel sick right now

That explains a lot

But you’re not alone, you may have noticed a large number of your friends, family and colleagues struck down with illness right now.

Experts have now revealed the potential cause of the sudden spike in colds, flu and Covid-19 that are sweeping the nation.

According to the Health Security Agency, positive Covid-19 tests rose from 4% at the end of March to 14% by the end of June and that number has continued to rise to 17% as of July 10.

A research fellow at Bristol University, Dr Allen Haddrell said these increases are more likely due to the ‘changes in population, behaviour and environmental changes indoors’ as viruses are rarely transmitted outdoors.

School holidays, festival season and the Euros have largely been blamed for the spread but Haddrell points to air conditioning units as another factor in this current increase in illness.

Speaking to the Mirror, he said: “In offices, people use air conditioning, because having a window open might not cool the area down very much.

“Many of these air conditioning units are cooling the air but also pushing it around and sealing the building in a sense, so that could also lead to an increase in transmission.”

Haddrell was quizzed on the increase in Coronavirus cases which he replied was no surprise.

He said: "We're four years into a global pandemic, and we've learnt lots of different ways to deal with this – and yet people aren't really engaging with them anymore. So it's really not surprising we keep experiencing these waves.

"Boosters work, masks work great, ventilation (opening windows), social distancing and avoiding crowds, plus co2 monitors to detect how much ventilation you're getting in an indoor space. The higher the co2 levels, the longer the virus will persist in the air. Having at least one in the office will give you a sense of what your indoor air quality is like."

Those who didn’t catch covid in the winter months are more likely to catch it this summer as their immune system is lower.

A falling rate of vaccinations alongside new strains of the virus are also causing an increase in cases.