In a world recovering from the COVID-19 pandemic, the last thing we need are unsubstantiated media reports on another virus.

Recent media reports or a “respiratory tract virus” outbreak in China is a case in point. Most people would not be familiar with the disease caused by the human metapneumovirus virus.

According to WHO, the current levels of activity for the current viral respiratory tract infections in the northern hemisphere - influenza, respiratory syncytial virus, human metapneumovirus and mycoplasma pneumonia – are consistent with previous years. The report states there have not been any unusual outbreak patterns in China for this time of year and Chinese health officials report that their health system is NOT overwhelmed.

Respiratory tract infections have certainly increased since the beginning of winter as might be expected when people are driven indoors.

Influenza is currently the most reported pathogen followed by mycoplasma pneumonia in those aged 5 to 14 years.

What is Human Metapneumovirus (hMPV) Disease?

Human metapneumovirus is a common cause of respiratory tract infections in children. It was first identified in the Netherlands in 2001 but serology surveys, investigating immunity, would suggest it’s been a common cause of “colds” for many decades.

Most children (over 80%) have been exposed to hMPV by the age of 5 years. It is commonly seen as an upper respiratory tract infection with 5-10% progressing to a chest infection. The immunity is not complete and allows for repeat infections later in life. Those most at risk of serious disease include infants under 6 months, adults with chronic lung issues and those who might be immune suppressed.

The disease is mostly mild in healthy young adults but increases in severity with increasing age. It is unusual for individuals to be infected and have no symptoms at any age.

When do outbreaks occur?

Human metapneumovirus outbreaks are more common in late winter and early spring. This seasonal pattern was disturbed post COVID, with outbreaks of the disease occurring in autumn and early winter. This was likely a catch-up phase after a period of enhanced attention to social distancing, hand hygiene and masks. Transmission is by droplet infection and touching infected objects.

In an Australian study of hMPV disease, spring and winter were identified as the seasons of most risk. The study suggested there was little difference in the clinical presentation to separate it from other common respiratory tract infections.

Human Metapneumovirus in Australia

Human metapneumovirus is not a notifiable disease in Australia.

It is often identified when a respiratory tract swab is taken.

• Treatment is only supportive
• Antiviral medications are not effective
• There is no vaccination.

Protecting yourself from hMPV while travelling

Respiratory tract infections are a major cause of traveller morbidity. Travellers should be aware of the risk and look at ways to reduce exposure.