Genomic epidemiological study reveals divergent transmission dynamics and genotype-linked mortality in Dabie bandavirus infection, highlighting the need for targeted regional surveillance.
Key Points
To identify the ecological determinants and phylogeographic transmission networks driving the decoupled inland-high-incidence versus coastal-high-fatality patterns of Dabie bandavirus in East Asia.
Integrated 1,820 global genomes of Dabie bandavirus (SFTSV), a clinical cohort of 936 patients, and nationwide surveillance records of 27,457 cases in China.
Conducted ecological niche modeling, Bayesian discrete phylogeography, and genotype-phenotype association analyses to assess viral transmission routes and patient outcomes.
SFTS incidence displayed divergent climatic sensitivities, with inland spread governed by temperature fluctuations and coastal spread limited by a monthly sunshine threshold (> 200 hours/month).
Coastal regions were dominated by genotype B, whereas inland regions co-circulated genotypes A, C, and D; Zhejiang province served as a transmission hub with higher viral recombination than inland regions (11.0% vs. 3.5%, P < 0.001) and frequent lineage exchange with Japan and South Korea.
Genotypes B and D were linked to increased clinical mortality in coastal and inland cohorts, respectively, with the RdRp-N828S substitution identified as a significant molecular marker of fatal infection.