Direct transmission of SFTSV from dogs to humans: Molecular confirmation and risk assessment.

Abstract

OBJECTIVES: This study aimed to investigate the potential for dog-to-human transmission of Severe Fever with Thrombocytopenia Syndrome Virus (SFTSV) and characterize viral shedding patterns in naturally infected dogs. METHODS: We conducted genomic analysis of SFTSV strains isolated from an infected dog and its owner using whole-genome sequencing. Viral loads were quantified in canine saliva, urine, and stool samples via qRT-PCR during the acute infection phase. RESULTS: Genomic sequencing revealed 100% identity between viral strains from the dog and owner. The dog exhibited exceptionally high viral loads, particularly in bloody stools (2.2 × 10copies/mL) and saliva (2.3 × 10copies/mL), with persistent shedding observed throughout the clinical course. The owner developed SFTSV infection 14 days after the dog's symptom onset. CONCLUSIONS: This study provides the first molecular confirmation of direct SFTSV transmission from dogs to humans, identifying bloody stools and saliva as high-risk transmission sources. These findings underscore the importance of including dogs in SFTSV surveillance systems and implementing protective measures when handling sick pets in endemic areas.