Overview
- WastewaterScan data show high HMPV concentrations across many Northern California communities, including Redwood City, Merced, Novato and Sunnyvale.
- CDC/NREVSS reporting indicates HMPV accounted for just over 5% of weekly positive respiratory virus tests as of Feb. 21, 2026, below national peaks seen in 2024 and 2025.
- Clinicians warn that the virus typically causes cold‑like illness but can lead to bronchitis, pneumonia, croup or severe asthma attacks in infants, older adults and immunocompromised people.
- Public-health officials note seasonal circulation from winter through spring, with recent wastewater signals strongest in Northern California and some elevated activity reported along parts of the Northeast.
- Care remains supportive — rest, fluids and at‑home symptom relief — with hospitals using oxygen therapy, steroids or IV fluids for severe cases, and prevention guidance focuses on handwashing, cleaning surfaces, ventilation and staying home when sick.