We’re now deep into flu season here in the U.S., and word of a respiratory infection called HMPV increasing in China might bring people memories of early 2020, before the COVID-19 pandemic took hold. However, public health officials say there isn’t a reason to panic.
Here’s what we know about HMPV.
According to the World Health Organization, data published by China shows that acute respiratory infections increased through Dec. 29, including seasonal influenza, rhinovirus, RSV, and human metapneumovirus (HMPV) – particularly in northern provinces of China. Acute respiratory infections such as these often increase during the winter months in the Northern Hemisphere.
“Recently, there has been interest in HMPV cases in China including suggestions of hospitals being overwhelmed,” said the WHO in a Tuesday update. “HMPV is a common respiratory virus found to circulate in many countries in winter through to spring, although not all countries routinely test and publish data on trends in HMPV. While some cases can be hospitalized with bronchitis or pneumonia, most people infected with HMPV have mild upper respiratory symptoms similar to the common cold and recover after a few days.”
HMPV was first discovered in 2001 and it is in the Pneumoviridae family that also includes the respiratory syncytial virus (RSV), another common infection at this time of year, per the U.S. Centers for Disease Control and Prevention. It can cause upper and lower respiratory disease in people of all ages, especially young children, older adults, and people with weakened immune systems.
About 10% to 12% of respiratory illnesses in children are caused by HMPV, according to researchers cited by the Cleveland Clinic. It said most cases are mild, but that around 5% to 16% of children who contract the virus will develop a lower respiratory tract infection like pneumonia.
Dr. Denis Nash, executive director at CUNY Institute for Implementation Science in Population Health, joined Audacy in June 2023 to discuss HMPV.
“It is a respiratory virus like COVID, like RSV, and it’s seasonal. We usually see it circulating in the winter and early spring of each year. And in recent years with COVID, these retroviruses were less likely to be circulating than usual,” said Nash. “And so now that people are back in contact with each other more, there’s more intermixing.”
That remains true now, more than a year later. Nash also said that HMPV symptoms are similar to COVID-19 symptoms or common cold symptoms. It is generally less severe than COVID, he added, and less likely to land people in the hospital.
In China, the WHO reported that the most commonly detected respiratory pathogen currently affecting people with acute respiratory infections this season is influenza. It also said that data does not indicate any unusual outbreak patterns.
“Chinese authorities report that the health care system is not overwhelmed and there have been no emergency declarations or responses triggered,” said the health organization. “WHO continues to monitor respiratory illnesses at global, regional and country levels through collaborative surveillance systems, and provides updates as needed.”
To mitigate the spread of all acute respiratory infections, China has been providing health messages to the public. With multiple pathogens circulating, such as the flu and HMPV, there is a risk of burdening health facilities.
Precautions for preventing the spread of infections suggested by the WHO include staying home when sick and seeking medical care for severe symptoms. People can also protect themselves by wearing face masks in crowded or poorly ventilated spaces, practice regular handwashing and get recommended vaccines.
“Based on the current risk assessment, WHO advises against any travel or trade restrictions related to current trends in acute respiratory infections,” said the organization.
Margaret Harris of the WHO said the mortality rate for HMPV has been very low. She also said there have been no emergency responses or emergency declarations triggered.