Emergence and Molecular Epidemiology of Human Metapneumovirus in Greece in the Post-COVID Era

Recent reports have advocated the global resurgence of human metapneumovirus (hMPV) infections in the post-COVID-19 era. Considering the absence of relevant data from Greece, the present study aimed to explore the molecular epidemiology and possible resurgence of significant genotypic variants. Whole genome and F gene-specific sequencing were implemented in order to obtain complete information on the genotype and lineage distribution of circulating hMPV strains in Greece. The results showed a statistically significant increase in monthly positivity rates in 2025, especially from February to April, compared to the respective period in 2024. Overall, 21 strains were classified as genotype A2.2.2 (42.9%) and 27 as genotype B2 (55.1%), whereas only one strain belonged to genotype B1. The G gene of most completely sequenced A2.2.2 strains harbored a 111nt duplication sequence and a genotype-specific pattern of N-glycosylation sites. Maximum likelihood and time-scaled, Bayesian phylogenetic analyses demonstrated the dominance of specific sub-lineages at the regional level and international transmission events. This complex epidemic pattern in conjunction with the differential evolutionary pressure exerted on the hMPV genes, advocates continuous surveillance of hMPV epidemiology with multiple genes, or complete genome sequencing methodologies.