Background Gammaherpesviruses co-evolve with their hosts, resulting in species-specific associations and restricted host tropism. In lagomorphs, six herpesviruses (LeHV-1 to LeHV-6) have been identified, with LeHV-4 being associated with mortality in European rabbits (Oryctolagus cuniculus), while the others cause asymptomatic infections. LeHV-5 has been hypothesized to contribute to high morbidity and mortality in Iberian hares (Lepus granatensis) when in presence of concomitant infections such as myxomatosis. However, herpesvirus infections in wild and domestic lagomorphs remain poorly understood.

Methods Here, we conducted the first large-scale screening for herpesviruses in lagomorphs. Using a generalist PCR, we analyzed over 1,000 DNA samples from European rabbits, hares (Lepus spp.), cottontails (Sylvilagus spp.), pikas (Ochotona spp.), pygmy rabbits (Brachylagus idahoensis), volcano rabbits (Romerolagus diazi), Amami rabbits (Pentalagus furnessi), and riverine rabbits (Bunolagus monticularis).

Results Herpesviruses were detected in 75 samples (7.24%), revealing a putative novel virus in pikas, with ~80% similarity to known gammaherpesviruses. We further show circulation of LeHV-5 in European and mountain hares for the first time.

Conclusions These findings expand the current knowledge of herpesvirus diversity in lagomorphs. Given their potential role in immunosuppression and disease interactions, particularly with myxoma virus, further research is needed to assess their impact on host health and population dynamics.