Human metapneumovirus: an unexpected health burden
A couple of weeks ago, ‘Winter viruses and how to beat them’ aired on BBC2. The episode discussed the major viruses responsible for winter illness, including Influenza, Norovirus, and Respiratory syncytial virus. What the program didn’t touch on was another important winter virus: Human metapneumovirus (HMV). This is probably because it was not known how much of a health burden this virus was, until the publication of a recent study in New England Journal of Medicine which has shown the rates of hospitilisation in children under five with this virus is similar to influenza rates.
The virus was discovered in 2001, where it was identified in Dutch children with broncholitis. It is widespread and the second most common cause of pediatric lower respiratory tract infections. But until this study was carried out, not much was known about the epidemiology of this virus and its true impact on pediatric respiratory illness. This study was carried out from 2003 to 2009 and involved taking samples from over 10,000 children under the age of five. While RSV is the most common cause of illness in children under 1, this study found HMV affected more children over this age compared to RSV. The virus was detected in 6% of inpatients and 7% of outpatients and caused illness in otherwise healthy children. Those with HMV were more likely to be hospitilised for longer compared to other respiratory viruses.
This study has shown for the first time that HMV is a significant health burden and we may hear a lot more about this virus in the future. Now more is known about how much of a health burden HMV is, hopefully more funding will be given to developing antimicrobial drugs and a vaccine.