NREVSS | Human Metapneumovirus Clinical Features | CDC

NREVSS | Human Metapneumovirus Clinical Features | CDC

• Human metapneumovirus (HMPV)—a recently identified virus—can cause respiratory disease, especially in young children.
• HMPV leads to about 20,000 hospitalizations each year in the US among kids younger than 5 years.
• Healthcare professionals should consider HMPV, along with flu and respiratory syncytial virus (RSV), as a potential diagnosis when they see patients with respiratory illness, especially during late winter and early spring.

Human Metapneumovirus (HMPV) Clinical Features

About HMPV

Human metapneumovirus (HMPV) can cause upper and lower respiratory disease in people of all ages, especially among young children, older adults, and people with weakened immune systems. HMPV was discovered in 2001 and is in the paramyxovirus family along with measles and respiratory syncytial virus (RSV). Broader use of molecular diagnostic testing has increased identification and awareness of HMPV as an important cause of upper and lower respiratory infection.

Symptoms

Symptoms commonly associated with HMPV include cough, fever, nasal congestion, and shortness of breath.  Clinical symptoms of HMPV infection may progress to bronchiolitis or pneumonia and are similar to other viruses that cause upper and lower respiratory infections. The incubation period is estimated to be 3 to 6 days, and the median duration of illness can vary depending upon severity but is similar to other respiratory infections caused by viruses.

Surveillance and Seasonality

Surveillance data from CDC’s the National Respiratory and Enteric Virus Surveillance System (NREVSS) shows HMPV to be most active during late winter or early spring in temperate climates.

Transmission

HMPV is most likely spread from an infected person to others through –

• secretions from coughing and sneezing,
• close personal contact, such as touching or shaking hands, and
• touching objects or surfaces that have the viruses on them then touching the mouth, nose, or eyes.

In the U.S., HMPV circulates in distinct annual seasons. HMPV circulation begins in winter and lasts until or through spring. HMPV, RSV, and influenza can circulate simultaneously during the respiratory virus season. 

Prevention and Treatment

There are steps that can be taken to help prevent the spread of HMPV and other respiratory viruses. Specifically, people who have cold-like symptoms should

• Cover their coughs and sneezes
• Wash their hands frequently and correctly (with soap and water for 20 seconds)
• Avoid sharing their cups and eating utensils with others
• Refrain from kissing others

In addition, cleaning possible contaminated surfaces (such as doorknobs, shared toys) may potentially help stop the spread of HMPV.

In healthcare settings, healthcare providers should follow CDC’s 2007 Guideline for Isolation Precautions: Preventing Transmission of Infectious Agents in Healthcare Settings.

There is no specific antiviral therapy for HMPV. Medical care is supportive.

Since HMPV is a recently recognized respiratory virus, healthcare professionals may not routinely consider or test for HMPV. However, healthcare professionals should consider HMPV testing during winter and spring, especially when HMPV is commonly circulating.

Health departments can contact CDC for assistance with laboratory diagnostics or consultation through the CDC Unexplained Respiratory Disease Outbreaks work group.

Laboratory Diagnosis

Infection with HMPV can be confirmed by –

• direct detection of viral genome by reverse transcriptase polymerase chain reaction assays,
• direct detection of viral antigens in respiratory secretions using immunofluorescence or enzyme immunoassay, and
• rarely by isolation and identification of the virus in cell culture.

Resources

• National Respiratory and Enteric Virus Surveillance System (NREVSS)
• Unexplained Respiratory Disease Outbreaks (URDO)

References

• American Academy of Pediatrics. Human metapneumovirus. Red Book 2015 Report of the Committee on Infectious Diseases [online edition].
• CDC. Outbreaks of human metapneumovirus in two skilled nursing facilities — West Virginia and Idaho, 2011–2012. MMWR. 2013;62(46):909-13.
• Edwards KM, Zhu Y, Griffin MR et al. Burden of human metapneumovirus infection in young children. New Eng J Med. 2013;368(7):633-43.
• Widmer K, Zhu Y, Williams JV et al. Rates of hospitalizations for respiratory syncytial virus, human metapneumovirus and influenza virus in older adults. J Infect Dis. 2012;206(1):56-62.
• Heikkinen T, Österback R, Peltola V, Jartti T, Vainionpää R. Human metapneumovirus infections in children. Emerg Infect Dis [serial the Internet]. 2008 Jan.
• Pelletier G, Dery P. Abed Y et al. Respiratory tract reinfections by the new human Metapneumovirus in an immunocompromised child. Emerg Infect Dis [serial on the Internet]. 2002 Sep.
• Stockton J, Stephenson I, Fleming D, Zambon M. Human Metapneumovirus as a cause of community-acquired respiratory illness. Emerg Infect Dis[serial the Internet] 2002 Sep.
• Va den Hoogen BG, de Jong JC, Goen J, Kuiken T, de Groot R, et al. A newly discovered human pneumovirus isolated from young children with respiratory tract disease. Nat Med. 2001;7(6):719-24.