Expert reassures

hMPV infections: World not facing new pandemic

Electron microscope image of the human metapneumovirus(Bild: CDC)

Despite reports of an increase in human metapneumovirus (hMPV) infections in China, the world is not facing a new pandemic. "We really don't need to worry about that," reassured Austrian vaccine expert Florian Krammer at the Austrian Vaccination Day in Vienna on Saturday.

"The human metapneumovirus is very similar to RSV (respiratory syncytial virus; note). By the age of ten, practically one hundred percent of people are seropositive (i.e. they have been infected and have antibodies in their blood; note). The human metapneumovirus (hMPV) is not a new pandemic," says Krammer (pictured below), who conducts research at the Icahn School of Medicine in New York and at MedUni Vienna.

Pathogen causes respiratory tract infections
The virus causes respiratory infections that cause mild symptoms, such as a cold, in both children and older people. However, according to the expert, infections with hMPV cause between five and ten percent of hospitalizations of young children in the USA.

What is the human metapneumovirus?

The human metapneumovirus was first isolated in 2001 and assigned to the then new virus family Pneumoviridae in 2016. It is genetically and clinically very closely related to the more common respiratory syncytial virus. It mainly affects infants and children.

WHO: Neither new nor particularly dangerous
The World Health Organization (WHO) recently sought reassurance in the face of reports of rising numbers of respiratory infections with hMPV in China. The pathogen is neither new nor particularly dangerous, emphasized a WHO spokeswoman in Geneva. No emergency situation had been declared in China.

The virus usually only causes normal cold symptoms. In some cases, however, HMPV can lead to more serious illnesses such as bronchitis or pneumonia. This risk mainly affects people with very weak immune systems, including the elderly and patients undergoing cancer treatment.