Ranavirus-Positive Hatchling Eastern Box Turtles (Terrapene carolina carolina) Suggest Vertical Transmission without...

Area of Science:

• Herpetology
• Virology
• Ecology

Background:

• Ranaviruses are highly virulent emerging pathogens affecting ectotherms like reptiles.
• Ranavirus epizootics have caused significant mortality in turtle populations.
• Transmission routes, especially vertical transmission, remain poorly understood in reptiles.

Purpose of the Study:

• To investigate the potential for vertical transmission of ranavirus in eastern box turtles (Terrapene carolina carolina).
• To screen reproductive females and their offspring for ranavirus presence and assess potential disease impact.

Main Methods:

• Screened 25 female eastern box turtles and 74 offspring for ranavirus.
• Collected samples from females multiple times during the reproductive season and up to 3 years prior.
• Collected offspring samples at hatching and 8 months later.

Main Results:

• Seven reproductive females tested positive for ranavirus, with detections occurring 2-3 years before monitoring.
• Nine hatchlings from six clutches tested positive, seven from females without prior ranavirus history.
• Positive hatchlings showed low viral loads, no clinical signs, and did not transmit the virus to clutchmates; all survived captive rearing.

Conclusions:

• Vertical transmission of ranavirus is suggested in box turtles.
• Observed low viral loads did not lead to disease in hatchlings.
• Further research is required to elucidate transmission modes and population-level effects.