ARC has recently been made aware of a newly described fungal pathogen in the UK, which has been associated with Snake Fungal Disease (SFD). SFD is an emerging infectious disease caused by the fungal pathogen Ophidiomyces ophiodiicola. As the name suggests, this infection is only known to affect snakes and until recently had only been recorded in wild snakes from North America. However, a recent study published open access in Scientific Reports conducted by the Institute of Zoology, with the support of the Garden Wildlife Health project, has confirmed that O. ophiodiicola and SFD have recently been detected in wild snakes in Europe, including the UK.

Grass snake skin shed with lesions positive for Ophidiomyces ophiodiicola. Image copyright Zoological Society of LondonIn the UK, SFD was first detected in 2015 in a wild grass snake (Natrix natrix) found in the East of England, which was showing altered behaviour patterns. Initially, the snake was observed to be lethargic and in poor body condition, showing signs of dehydration. It was then taken into care, but subsequently died. Post-mortem examination revealed signs of a skin disease, and approximately 10% of the scales on the underside of the body had small (1-5 mm diameter) brown lesions with an irregular surface. Microscopic examination confirmed that the skin lesions were associated with a fungal infection. This provoked a suspicion that it could be associated with SFD. Subsequent fungal culture and genetic sequencing confirmed the agent to be O. ophiodiicola.

Grass snake (Natrix natrix) with skin lesions due to SFD copyright ZSL

As far as we are aware, this was the first time O. ophiodiicola and SFD had been found in a wild snake outside North America. Further testing of grass snake carcasses and skin sheds which had been collected by volunteers under the ARC Genebank project and the Garden Wildlife Health project has since detected O. ophiodiicola from multiple locations across England. In mainland Europe, O. ophiodiicola was also confirmed in 2016, in a dice snake (Natrix tessellata) from the Czech Republic.

Because O. ophiodiicola has been identified from sloughs/carcasses of wild snakes collected since 2010, with a wide distribution across England, it is suggested that this fungus is already well-established in the UK. In addition, findings from genetic studies and fungal cultures indicate that the European strains of O. ophiodiicola affecting wild snakes are distinct from the strains known to infect snakes in the eastern USA and there is no evidence to indicate that O. ophiodiicola was recently introduced to Europe from North America or vice versa.

How you can get involved

Continued monitoring is required to determine whether other native snake species, including the European adder (Vipera berus) and smooth snake (Coronella austriaca), are susceptible to O. ophiodiicola infection and/or SFD.

We still do not fully understand the implications of these findings for the health of our native snakes. However, we will continue to support the Institute of Zoology in this important research by asking volunteers and professional reptile workers to continue to collect sloughs through the ARC Genebank project, and report dead reptiles through the Garden Wildlife Health project.

Biosecurity Measures

To date, O. ophiodiicola is only known to infect snakes. However, the fungal infection has been documented in captive snakes from multiple countries, including Great Britain, and it is possible that it may be transmitted between wild and captive snakes. Therefore, as a precautionary measure we recommend that field-workers who also keep captive snakes maintain good biosecurity when handling pet snakes and conducting field activities. In addition, substrate from captive snake vivaria should be carefully disposed of, such that it cannot come into contact with wild snakes.

More information

Franklinos, L.H.V. et al (2017) Emerging fungal pathogen Ophiodiomyces ophiodiicola in wild European snakes. Scientific Reports 7, 3844, doi:10.1038/s41598-017-03352-1

ARC Reptile Genebank project

Garden Wildlife Health project

GWH Snake Fungal Disease Fact Sheet