Host range specificity of flaviviruses: correlation with in vitro replication

Area of Science:

• Virology
• Arthropod-borne Viruses
• Cell Culture Models

Background:

• Vector-borne flaviviruses are traditionally classified as mosquito-borne or tick-borne.
• Occasional cross-vector isolations challenge strict vector range specificity.
• Understanding flavivirus host range is crucial for disease transmission studies.

Purpose of the Study:

• To comprehensively reexamine the host range of various flaviviruses, including mosquito-borne, tick-borne, insect-specific, and non-arboviruses.
• To evaluate the ability of flaviviruses to replicate in cell cultures derived from different host types (mosquitoes, ticks, vertebrates).
• To assess the utility of a serial passage cell culture assay for determining flavivirus host range.

Main Methods:

• Utilized serial passage experiments in vitro using cell cultures from mosquitoes, ticks, and vertebrates.
• Tested flaviviruses representing mosquito-borne, tick-borne, insect flaviviruses, and non-arboviruses.
• Assessed viral replication across five consecutive passages as a criterion for host range determination.

Main Results:

• Replication patterns in cell cultures largely agreed with conventional vector-borne flavivirus groupings.
• Phylogenetic clustering of viruses correlated with observed host range specificity in cell culture.
• The assay demonstrated consistent results for established flavivirus groups.

Conclusions:

• The findings support the traditional classification of flaviviruses into mosquito-borne and tick-borne groups based on replication capabilities.
• The serial passage cell culture assay is a valuable supplementary tool for investigating flavivirus host range, especially in ambiguous or unknown cases.
• This method aids in clarifying vector-virus associations for flaviviruses.