Detection of Bufonid Herpesvirus 1 and Ranid Herpesvirus 3 in Native Amphibians in Schleswig-Holstein, Germany, 2022-23.

Amphibians worldwide are increasingly threatened, with some populations experiencing significant declines. Infectious diseases play a major role in many of these scenarios. Bufonid herpesvirus 1 (BfHV1) and ranid herpesvirus 3 (RaHV3) are both relatively recently discovered pathogens of European amphibians, and their distribution and host species spectrums are not yet fully understood. In the present study, native amphibians were sampled at four locations in Schleswig-Holstein, northern Germany, during the spawning seasons from March to June 2022 and 2023. In total, 611 skin swabs from nine amphibian species were analyzed for BfHV1 and RaHV3 by using PCR. The overall prevalence was 10.64% for BfHV1 and 4.91% for RaHV3. Prevalence varied significantly (P <0.05) between the species tested and the locations: BfHV1 was found in common toads (Bufo bufo, 62.82%), common frogs (Rana temporaria, 12.28%), moor frogs (Rana arvalis, 7.55%), natterjack toads (Epidalea calamita, 4.17%), water frogs (Pelophylax sp., 1.54%), northern crested newts (Triturus cristatus, 1.27%), and smooth newts (Lissotriton vulgaris, 0.68%), whereas RaHV3 was found in common frogs (43.86%), northern crested newts (3.80%), and smooth newts (1.36%). No macroscopic pathogen-specific skin lesions were noted in any of the animals during sample collection. The role of these herpesviruses in health and disease of native amphibians, as well as the role of various species in their epidemiology, requires further study.