What is Metapneumovirus (MPV)?

From the Guidelines

Human Metapneumovirus (hMPV) is a paramyxovirus that causes respiratory tract infections, including upper respiratory tract infections (URTI) and lower respiratory tract infections (LRTI), primarily affecting young children, older adults, and people with weakened immune systems. The virus is closely related to Respiratory Syncytial Virus (RSV) and is commonly diagnosed by nucleic acid testing (NAT) 1.

Key Characteristics of hMPV

• hMPV infection can cause symptoms similar to the common cold, bronchitis, and pneumonia
• It is commonly diagnosed by NAT, with rates ranging from 2.5% to 9% during the first 2 years after allogeneic hematopoietic stem cell transplantation (HSCT) 1
• Asymptomatic and prolonged shedding has been reported in HSCT patients 1

Treatment and Management

• Treatment for hMPV is mainly supportive care, focusing on managing symptoms since there are no specific antiviral medications approved for this virus
• Recommended treatments include rest, adequate hydration, and over-the-counter medications like acetaminophen or ibuprofen to reduce fever and relieve pain
• For breathing difficulties, a cool-mist humidifier can help ease congestion
• In severe cases requiring hospitalization, supplemental oxygen, intravenous fluids, or mechanical ventilation may be necessary

Prevention Strategies

• Prevention strategies include frequent handwashing, avoiding close contact with sick individuals, and covering coughs and sneezes
• The virus spreads through respiratory droplets and typically causes illness lasting 1-2 weeks, with most people recovering fully without complications It is essential to note that no general recommendation for treatment can currently be made, although some centers consider treating hMPV LRTI with ribavirin and/or IVIG despite the lack of supporting studies 1.

From the Research

Definition and Characteristics of Metapneumovirus (MPV)

• Metapneumovirus (MPV) is a common pathogen that can cause both upper and lower respiratory tract infections, particularly in children, elderly adults, and immunocompromised hosts 2.
• It is an RNA virus of the Paramyxoviridae family, and has been isolated on every continent and from individuals of all ages 3.
• MPV causes 7 to 19% of all cases of acute respiratory tract infections (ARTIs) in both hospitalized and outpatient children, and the rate of detection in adults is approximately 3% 3.

Symptoms and Risk Factors

• Symptoms of MPV infection range from a mild cold to a severe disease requiring a ventilator and cardiovascular support 3.
• The main risk factors for severe disease upon MPV infection are the presence of a high viral load, coinfection with other agents, being between 0 and 5 months old or older than 65 years, and immunodeficiency 3.
• In young children, symptoms range from mild upper respiratory tract infections to severe lower respiratory tract infections (eg, bronchiolitis, croup, and pneumonia) 2.
• In adults, MPV reinfection typically presents with colds and flulike clinical manifestations 2.

Diagnosis and Treatment

• Reverse transcription polymerase chain reaction (RT-PCR) is the most sensitive test with which to detect MPV infection 2.
• Direct detection of MPV antigens with an immunofluorescent antibody test is available but is less sensitive than PCR 2.
• Antibody testing is used mainly for retrospective diagnosis and for epidemiological studies 2.
• The mainstay of treatment of MPV infections is supportive, and antiviral drugs are employed in cases of severe disease as a last resort 3.
• Ribavirin and immunoglobulins have been used in some patients, but the real efficacy of these treatments is unclear 3.