Adenovirus is contagious through various forms, including close personal contact, such as shaking hands, and through the air, like coughing and sneezing. Eric Sachinwalla, an infectious disease doctor based in Philadelphia, Pennsylvania, has emphasised that anyone experiencing any of the symptoms below should isolate, as these could be signs of adenovirus or other contagious diseases and illnesses.

At the moment, there  is no known treatment. It is believed that some over-the-counter pain medicines or fever reducers will help ease symptoms, but shouldn’t be considered “cures” to rid the adenovirus.

A list of adenovirus symptoms currently includes:

• common cold or flu-like symptoms
• fever
• sore throat
• acute bronchitis (inflammation of the airways of the lungs, sometimes called a “chest cold”)
• pneumonia (infection of the lungs)
• pink eye (conjunctivitis)
• acute gastroenteritis (inflammation of the stomach or intestines causing diarrhea, vomiting, nausea, and stomach pain)
• diarrhoea
• vomiting

Dr Sachinwalla said: “It’s pretty contagious because it’s heartier than other viruses – soap and water, or everyday disinfectant, won’t kill it, so it tends to live in the environment longer.”

The elderly, pregnant, or immunocompromised may want to keep a closer eye on their symptoms, as they are vulnerable to complications from all viruses and diseases.

Normally, the symptoms should begin to go away after approximately two days. However, if it goes on for longer than three days without any relief, then this is also a red flag.

Dr Sachinwalla explained that a surge in flu cases in the southern hemisphere earlier in the year may have led to a rise in cases in the northern hemisphere now. He added that there is also the factor of fewer people going for a flu jab.