Ophidiomyces ophiodiicola ("Snake fungal disease" or SFD)

Test code: F0012 - Ultrasensitive qualitative detection of Ophidiomyces ophiodiicola by real time polymerase chain reaction.

Test F0012 is included in P0052 - snake and lizard quarantine PCR panel

Snake fungal disease (SFD) is an emerging disease of conservation concern in eastern North America. Ophidiomyces ophiodiicola, which causes SFD, has been isolated from over 30 species of wild snakes from six families in North America. Snake species that are affected include the northern water snake (Nerodia sipedon), eastern racer (Coluber constrictor), rat snake (Pantherophis obsoletus species complex), timber rattlesnake (Crotalus horridus), massasauga (Sistrurus catenatus), pygmy rattlesnake (Sistrurus miliarius), milk snake (Lampropeltis triangulum), and others.

Ophidiomyces ophiodiicola is a keratinophilic fungus from the family Onygenaceae of the order Onygenales. It was first described as Chrysosporium ophiodiicola until DNA sequencing confirmed that it was more related to the family Onygenaceae. Its physiological characteristics allow it to grow in many ecosystems.

Clinical presentation and severity of SFD vary by snake species. Snakes infected with O. ophiodiicola can develop symptoms such as scabs or crusty scales, subcutaneous nodules, premature separation of the outermost layer of the skin (stratum corneum) from the underlying skin, other abnormal shedding, white opaque cloudiness of the eyes not associated with shedding, or localized thickening or crusting of the skin (hyperkeratosis). Skin ulcers, swelling of the face, and nodules in the deeper tissues of the head have also been documented.

Transmission of the fungus can be by direct contact between infected animals or with environmental contaminants. Environmental monitoring thus is important to prevent infection.

While fungal culture may be used to presumptively diagnose the fungal infection, molecular detection by polymerase chain reaction is the method of choice to provide highly specific, sensitive and rapid identification of the fungus (Bohuski et al., 2015).

Utilities:

• Help confirm the disease causing agent
• Shorten the time required to confirm a clinical diagnosis of Cryptosporidium infection.
• Help ensure that animal groups and facilities are free of Cryptosporidium species
• Early prevention of spread of these protozoa
• Minimize human exposure to these protozoa

Reference:
Bohuski, E.,  Lorch, J.M., Griffin, K.M. and Blehert, D.S. (2015) TaqMan real-time polymerase chain reaction for detection of Ophidiomyces ophiodiicola, the fungus associated with snake fungal disease. BMC Vet Res. 11: 95.

Specimen requirements: Lesion swab, or skin swab, or environmental swab, or 0.2 ml of shed skin, or 0.2 ml fresh, frozen or fixed tissue.

Contact Zoologix if advice is needed to determine an appropriate specimen type for a specific diagnostic application. For specimen types not listed here, please contact Zoologix to confirm specimen acceptability and shipping instructions.

For all specimen types, if there will be a delay in shipping, or during very warm weather, refrigerate specimens until shipped and ship with a cold pack unless more stringent shipping requirements are specified. Frozen specimens should be shipped so as to remain frozen in transit. See shipping instructions for more information

Turnaround time: 2 business days

Methodology: Qualitative real time PCR

Normal range: Nondetected