Evidence of nosocomial human-to-human transmission of Dabie bandavirus: A clinical, epidemiological and virological investigation.
Abstract
Objective
To investigate nosocomial non-vector-borne transmission of Dabie bandavirus (DBV) using clinical, epidemiological, virological, and genomic evidence.
Methods
We conducted a comprehensive multidisciplinary study of six patients within a hospital setting, integrating detailed epidemiological contact tracing, dynamic monitoring and tracing of viremia, the neutralizing antibodies, hematologic and biochemical markers, viral isolation, and whole-genome sequencing of clinical specimens. Genomic analysis was used for phylogenetic placement and verification of high-confidence sequence differences between the index and secondary patients.
Results
This study demonstrated that DBV is capable of vector-independent human- to-human transmission in healthcare settings. Whole-genome sequencing showed that viruses isolated from the secondary cases were highly genetically related to the virus from the index case and clustered within an established Chinese lineage, strongly supporting a common origin and confirming that the secondary infections were acquired from the index patient through nosocomial transmission. Viral isolation and microneutralization assays further characterized the virological and humoral immune features of the secondary cases.
Conclusion
This study reports a nosocomial cluster of DBV infections, which occurred through human-to-human transmission. It highlights the value of integrating epidemiological investigation, virus isolation, microneutralization assays, and whole-genome sequencing to establish transmission chain, reconstruct the outbreak, and assess infection-control risks in this epidemiological event.