A recently discovered emerging pathogen has reared it’s ugly head. This pathogen is a variant of the deadly global pathogen known as Batrachochytrium dendrobatidis (Bd), but Batrachochytrium salamandrivorans (Bsal) attacks salamanders and newts rather than frogs and toads. Like Bd, Bsal causes a painful certain death.

History

Bsal was first discovered in 2013 in Belgium and the Netherlands after the discovery of large populations of salamanders dying. This pathogen was also discovered in captive salamander populations in Germany and the United Kingdom. It is suspected that Bsal is endemic to Asia and was spread to other countries via the international pet trade. Unfortunately, from 2010 – 2014, over an estimated 750,000 salamanders were imported into the U.S. This significantly increases the chance that salamanders and newts here in the U.S. have been infected. The western and eastern coastal states are at the greatest risk, with the east coast being number 1 on the list.

Present

As of late, the NWHC has been providing technical and diagnostic support for an intensivee surveillance effort in collaboration with the USGS Amphibian Research and Monitoring Initiative (ARMI). Sites with the hhighest probability of introduction are being sampled first. The closely related Batrachochytrium dendrobatidis (Bd) has already affected more than 200 amphibian species, worldwide. It has caused the decline or extinction of at least 501 known amphibian species! So scientists are aggressively trying to get a handle on Batrachochytrium salamandrivorans before it is too late.

Symptoms

The following are some of the symptoms of Bsal:

• Skin lesions: Circular, black-rimmed lesions on the surface of the skin, and/or deep ulcers
• Skin shedding: Excessive shedding of skin
• Behavior: Apathy, anorexia, ataxia, lethargy, and death
• Mortality: High mortality rates at temperatures below 77ºF
• Epidermal: Impairment of critical skin functions, like respiration

Some animals can carry the fungus without showing any signs of distress. For example, in newts, the disease may be symptom-free for long periods of time. Bsal can be transmitted via contact with water, organic matter, or direct contact with an infected salamander or newt. Detection of the fungus is performed via a DNA (PCR) test, usually from a skin swab.

The Future

Fortunately, there is a cure for Bsal, just like there is for Bd. In 1 study, infected fire salamanders were treated with 2,000 IU/ml of polymyxin E and 12.5 μg/ml of voriconazole at 68ºF. This treatment cleared the infection in every subject. Another study exposed infected salamanders to 77°F for 10 days, which also cleared the infection from all tested subjects.

However, the issue is how to treat, via temperature control, wild specimens. Therefor, for now, the best option would be to treat with a topical spray of the antifungal drugs polymyxin E and voriconazole.