CASES of human metapneumovirus (HMPV), a common respiratory virus, are surging in parts of Asia, including China, Malaysia, India, and Kazakhstan. While the outbreak is significant, healthcare experts emphasize that it poses minimal global health risk thanks to widespread population immunity. HMPV, a seasonal virus similar to influenza and respiratory syncytial virus (RSV), typically peaks in late winter to early spring.
China recently reported an uptick in respiratory infections, with increased HMPV cases among children under 14. Reports of hospitals overwhelmed with respiratory patients in northern China raised concerns, prompting enhanced surveillance in the region and neighboring countries. However, experts underscore that the virus is neither new nor unexpected.
“In Asia, they are having a fairly large outbreak—might even call it an epidemic—of human metapneumovirus,” said Dr. William Schaffner, infectious disease specialist at Vanderbilt University Medical Center. “There’s no need to be panicky. But for those in higher-risk groups, this is a time to be careful.”
HMPV primarily causes mild symptoms like a runny nose, cough, and fever. Severe cases, though rare, may occur in young children, older adults, and immunocompromised individuals. The virus has been circulating for decades, with genetic studies tracing its origins to a bird virus that diverged 200–400 years ago, according to Dr. John Williams, pediatrician and infectious disease expert at the University of Wisconsin–Madison.
Although travelers from affected areas could bring the virus to the U.S., experts note that HMPV already circulates annually within the country. According to the Centers for Disease Control and Prevention (CDC), HMPV cases in the U.S. are currently low, with only 2% of diagnostic tests returning positive in late December. Last year, cases peaked in April, with 8% of tests showing positive results.
Reference: Scientific American. HMPV Cases Are Rising across Asia, but Experts Say Not to Panic. 2025. Available at: https://www.scientificamerican.com/article/what-is-human-metapneumovirus-and-why-are-cases-rising-in-china/. Last accessed: January 15, 2025.
Anaya Malik | AMJ
