Human Metapneumovirus Infection and Genotyping of Infants in Rural Nepal

Area of Science:

• Virology
• Epidemiology
• Pediatrics

Background:

• Acute respiratory tract infections pose a significant burden on infants.
• Human metapneumovirus (HMPV) is a key etiological agent of infant respiratory infections.
• Understanding HMPV in rural, low-resource settings is crucial for public health.

Purpose of the Study:

• To investigate genotypic variation of HMPV in infants in Nepal.
• To characterize molecular epidemiological patterns of HMPV infection.
• To assess HMPV infection in a rural, low-resource context.

Main Methods:

• Longitudinal study involving 3528 infants with respiratory symptoms (May 2011-April 2014).
• Mid-nasal swabs collected for HMPV detection using reverse-transcriptase polymerase chain reaction (RT-PCR).
• Sequencing of F and G genes for HMPV genotyping and phylogenetic analysis.

Main Results:

• HMPV detected in 5% of infants, with seasonality in fall and winter.
• Circulating genotypes identified as A2, B1, and B2, with HMPV-B predominating annually.
• Comparable median viral loads across genotypes; type B associated with increased cough duration and general respiratory symptoms.

Conclusions:

• Multiple HMPV genotypes circulate concurrently in rural Nepal, exhibiting distinct seasonality and alternating predominance.
• No significant differences in viral load were observed between HMPV genotypes.
• Symptom severity did not correlate with RT-PCR cycle threshold or HMPV genotype.