Chytrid Fungus and Ranavirus FAQ
What is chytrid? What is ranavirus?
Chytrid is a fungus, specifically Batrachochytrium dendrobatidis (aka Bd), that affects amphibians resulting in a disease called chytridiomycosis. Infected individuals suffer damage to their skin which may result in additional infections and impair respiration. This disease if often fatal and can infect populations very rapidly. Chytridiomycosis has been implicated in devastating declines in amphibian populations worldwide and is currently one of the greatest threats to amphibians, second only to habitat destruction.
Ranaviruses are members of the Iridovirus family and may infect insects, fish, amphibians, and turtles. This group includes the largemouth bass virus (LMBV) and Ambystoma tigrinum virus (ATV). Ranavirus infection in amphibians typically causes death in larvae or recently metamorphosed individuals and infected individuals often have ulcers on their skin. Turtles typically show signs of skin lesions, respiratory distress, and multiple organ failure.
Do these pathogens occur in Texas?
Yes. Both chytrid and ranavirus have been documented in Texas although the extent of their distribution is not known at this time.
Are these pathogens dangerous to humans?
No. Infections in birds, humans, or other mammals have not been documented.
How do I prevent the spread of these pathogens in Texas?
Given that these and other pathogens may be transmitted by humans, it is important to practice appropriate field hygiene when engaged in activities such as collecting bait or sampling aquatic organisms. The following protocols are intended for wildlife researchers working in aquatic environments but may be applicable to anyone who may come in contact with susceptible organisms (turtles, fish, and amphibians) or their habitat.
Practice appropriate procedures for decontaminating field equipment and clothing. Typically, removing mud and debris followed by soaking in bleach solution or quaternary ammonium disinfectant (i.e. Formula 409 and some Lysol products) is recommended. Additional decontamination protocols can be found at the following links:
- Amphibian Field Research
- The Declining Amphibian Task Force Fieldwork Code of Practice, www.fws.gov/ventura/docs/species/protocols/DAFTA.pdf
- Equipment Decontamination Protocol for Researchers Working in Yosemite National Park
The following link contains up-to-date decontamination protocols that address decontamination of caving equipment to control the spread of White Nose Syndrome (WNS) in bats but provides excellent guidelines that are applicable to decontamination with respect to the pathogens described above:
- White-nose Syndrome, www.fws.gov/whitenosesyndrome/
Never release captive pets into the wild or transport individuals from one place to another.