Bufonid herpesvirus 1 (BfHV1) associated dermatitis and mortality in free ranging common toads (Bufo bufo) in Switzerland

Abstract

Here we report the discovery and partial characterization of a novel herpesvirus tentatively named Bufonid herpesvirus 1 (BfHV1) from severe dermatitis in free ranging common toads (Bufo bufo) in Switzerland. The disease has been observed in toads every year since 2014, in spring, during the mating season, at different and distant locations. The virus is found in the skin and occasionally in the brain of infected toads. The genome of the virus is at least 158 Kb long and contains at least 152 open reading frames with a minimal length of 270 nt. The genome of BfHV1 contains all the signature genes that are present in alloherpesviruses. Phylogenetic analysis based on the amino acid sequence of the DNA polymerase and terminase proteins positions the novel virus among the members of the genus Batrachovirus, family Alloherpesviridae. This is the first herpesvirus ever characterized in common toads.

Emerging infectious disease threats to European herpetofauna

“…The gross clinical signs of amphibian herpesvirus infections appear to be conserved across affected species. Typically, lesions are present on the skin that may be tan (more terrestrial species), grey, or grey-blue in colour (typical of more aquatic species; see Origgi et al, 2017;Franklinos et al, 2018;Origgi et al, 2018). These are areas where the skin has become thickened and they may appear on any region of the body (Origgi et al, 2017;Franklinos et al, 2018;Origgi et al, 2018).…”

“…Typically, lesions are present on the skin that may be tan (more terrestrial species), grey, or grey-blue in colour (typical of more aquatic species; see Origgi et al, 2017;Franklinos et al, 2018;Origgi et al, 2018). These are areas where the skin has become thickened and they may appear on any region of the body (Origgi et al, 2017;Franklinos et al, 2018;Origgi et al, 2018). The number of lesions that appear on the skin of affected animals is often variable, ranging from one to covering most of the skin (Origgi et al, 2017;Franklinos et al, 2018;Origgi et al, 2018;Fig.…”

“…These are areas where the skin has become thickened and they may appear on any region of the body (Origgi et al, 2017;Franklinos et al, 2018;Origgi et al, 2018). The number of lesions that appear on the skin of affected animals is often variable, ranging from one to covering most of the skin (Origgi et al, 2017;Franklinos et al, 2018;Origgi et al, 2018;Fig. 6).…”

“…Origgi et al (2017) identified and characterised Ranid Herpesvirus 3 (RaHV3) from common frogs (R. temporaria) that were suffering from a proliferative dermatitis. Subsequently, Origgi et al (2018) described Bufonid Herpesvirus 1 (BfHV1) in common toads (B. bufo) that were also suffering from dermatitis. These are the first amphibian herpesviruses outside of North America to be fully characterised and described in wild caught amphibians.…”

Consensus PCR protocols for the detection of amphibian herpesviruses (Batrachovirus)

“…3,12 Two new batrachoviruses have been discovered in Switzerland: ranid herpesvirus 3 (RaHV-3) in free-ranging common frogs (Rana temporaria), and bufonid herpesvirus 1 (BfHV-1) in free-ranging common toads (Bufo bufo). 9,10 Affected frogs and toads have proliferative dermatitis characterized by epidermal hyperplasia. The discovery of these 2 novel herpesviruses within 2 y suggests that other herpesviral species may be present in free-ranging frogs and toads.…”