Burden of Human Metapneumovirus in India: Epidemiological Trends and Clinical Impact.

BACKGROUND: Human metapneumovirus (hMPV), discovered in 2001, has emerged as a significant respiratory pathogen, particularly affecting vulnerable populations such as children, the elderly, immunocompromised individuals, those with underlying pulmonary conditions, and healthcare workers. OBJECTIVE AND METHODS: This review aims to summarize current knowledge on hMPV and consolidate published data from India. A comprehensive literature search was conducted using databases including PubMed, Google Scholar, and DOAJ with specific keywords focused on hMPV. RESULTS: hMPV is an enveloped, single-stranded RNA virus belonging to the Paramyxoviridae family and exhibits seasonal variability, with peak incidence during winter and spring. Indian studies indicate that sublineage A2C is currently predominant, with earlier reports identifying B1, B2, and A2b. Among children in India with respiratory symptoms, hMPV prevalence ranges from 2.5% to 25.7%, while adult infection rates are lower. Higher prevalence rates were noted in the <2-year age group. Common clinical manifestations include cough, breathing difficulty, wheezing, headache, myalgia, coryza, and fatigue. Diagnosis is primarily achieved through RT-PCR or RT-qPCR. Complications such as pneumonia and bronchiolitis are frequently documented in pediatric cases. Although coinfections with RSV, Adenovirus, Rhinovirus, influenza, and parainfluenza viruses are reported, hMPV-related mortality remains comparatively low. No licensed vaccine or specific antiviral treatment for hMPV currently exists. CONCLUSION: In conclusion, hMPV constitutes a notable portion of severe acute respiratory infection (SARI) cases among both children and adults in India. It is important to consider the possibility of hMPV while investigating SARI cases.