New fears have emerged about the threat of ‘mystery’ virus hMPV which is behind wave of hospitalisations in China, it has been claimed, and is now on the rise globally.

As with all respiratory infections, one major risk is pneumonia, a potentially fatal lung condition, which can develop within days.

Experts globally called on Chinese authorities to reveal crucial details of the outbreak as cases began to surge in the UK and America.

hMPV belongs to the same family as the respiratory syncytial virus (RSV) and usually causes little more than a fever, cough and nasal congestion