Treatment of Human Metapneumovirus Infection
For immunocompetent adults, provide supportive care only—no antiviral therapy is indicated, as no agent has proven efficacy for HMPV. 1
Immunocompetent Patients
The mainstay of management is supportive care with rest, hydration, and symptomatic treatment 1. Specific supportive measures include:
- Oxygen therapy titrated to maintain adequate saturation 1
- Monitoring of vital signs, oxygen saturation, and respiratory status 1
- Fluid and electrolyte management 1
- Treatment of bacterial superinfection if suspected or documented 1
HMPV infections in otherwise healthy individuals are typically mild and self-limiting 2. The virus causes symptoms ranging from a mild cold to more significant upper respiratory tract disease, but severe complications are uncommon in this population 3.
Immunocompromised Patients and Severe Disease
For immunocompromised patients with lower respiratory tract disease (LRTID), consider ribavirin and/or intravenous immunoglobulin (IVIG), despite the absence of randomized controlled trial data supporting this approach. 1
When to Consider Antiviral Therapy
Treatment should be considered specifically for:
- Hematopoietic stem cell transplant (HSCT) recipients with pneumonia or lower respiratory tract involvement 1
- Leukemia patients with LRTID 1
- Patients with documented lower respiratory tract disease, not upper respiratory tract infection alone 1
Important Caveats
The evidence for ribavirin and/or IVIG is weak—no general recommendation for treatment can be made based on available evidence 4, 1. Single cases of severe disease and fatal outcomes have been reported even with treatment attempts 1. In HSCT patients with pneumonia, HMPV is frequently codetected with other pathogens including bacteria, fungi, other respiratory viruses, and cytomegalovirus, which obscures the true attributable morbidity and complicates treatment decisions 4, 1.
Risk Factors for Severe Disease
Be aware that severe disease is more likely with:
- High viral load 3
- Coinfection with other agents, especially respiratory syncytial virus 3
- Age extremes: 0-5 months old or >65 years 3
- Immunodeficiency 3
Current Treatment Landscape
No licensed vaccines or antiviral therapies are currently available for HMPV 5. Ribavirin and immunoglobulins have been used in some patients with severe disease as a last resort, but the real efficacy of these treatments remains unclear 3. Research is ongoing for monoclonal antibodies, vaccines, and novel antivirals, but none have reached clinical approval 5.
Infection Control Considerations
Implement standard and droplet precautions to prevent nosocomial transmission 1. HMPV demonstrates asymptomatic and prolonged shedding, particularly in HSCT patients, making infection control strategies essential 1.