The Centers for Disease Control and Pervention (CDC) is raising awareness about a new virus with respiratory symptoms like influenza and Covid that has landed a number of vulnerable Americans in hospitals this spring.
Human metapneumovirus, or HMPV, causes familiar symptoms like a cough, sore throat, runny nose, and fever, but is a different virus than the flu or Covid. At its 2023 peak in mid-March, nearly 11 per cent of specimens for the virus were positive — a number roughly 36 per cent higher than the standard peak of seven per cent positivity.
The surge in HMPV cases this spring is a worrying sign given that HMPV can lead to severe complications for young children, seniors, and people who are immunocomprimised and given that there is no vaccination to guard against its worst effects.
Despite its relatively low profile, HMPV is believed to be the second-leading cause of respiratory infections in children behind RSV and blood testing suggests that most children have had the virus before the age of five. Dr John Williams, a pediatrician at the University of Pittsburgh, told CNN that HMPV is “the most important virus you’ve never heard of.”
The virus was only discovered by researchers in the Netherlands in 2001, and testing for it outside of clinical settings remains rare. People often do not know that they’ve had HMPV or know what the virus to begin with. According to the CDC, the incubation period for HMPV is believe to be between three to six days with the median duration of illness running similar to other respiratory virsues.
Given the lack of protection against the virus, a spike in cases has serious implications for the health of the public. Serious cases can lead to bronchitis or pneumonia. But as HMPV becomes more widely recognised as an annual threat alongside viruses like the flu, RSV, and Covid, there is hope that the drug manufacturers who produced the Covid vaccines may be able to intervene.
According to CNN’s citation of the website clinicaltrials.gov, Moderna recently finished a study of an mRNA vaccine against HMPV and parainfluenza that could have an impact on the dangerousness of the virus.
In the meantime, the CDC recommends that doctors test patients exhibiting respiratory symptoms for HMPV — particularly in its peak seasons, the winter and the spring, and particularly in temperate climates.
