Metapneumovirus
Human metapneumovirus (hMPV) is responsible for 5% to 15% of hospital admissions for lower respiratory tract infection in infants and young children. Even though almost all adults have hMPV antibody hMPV can cause symptomatic reinfection throughout life, especially among older adults and immunocompromised persons. Risk factors for severe illness in adults include advanced age and underlying cardiopulmonary disease.
hMPV occurs most commonly during late winter or early spring in temperate climates, but summer outbreaks have been reported. Transmission likely occurs as a result of direct or indirect contact with infected secretions spread by fomites or through large particle aerosols. Incubation period for hMPV is 5–6 days. Clinical characteristics range from mild upper respiratory infection to respiratory failure and death. Reported fatality rates have varied from 0% to 31% of cases.
Due to the length of time required to detect hMPV, respiratory viral cultures are impractical for diagnostic purposes. Collection of a respiratory specimen within 3–4 days after symptom onset can increase detection of respiratory viruses by molecular diagnostic tests. hMPV is detected by the Biofire Filmarray for respiratory pathogens. Specimen requirement is a nasopharyngeal swab, nasal wash or bronchoscopy specimen.
