Short-Term Negative Effects of Vaccination Campaigns Against Myxomatosis and Viral Hemorrhagic Disease (Vhd) on the Survival of European Wild Rabbits

Abstract

The capture and handling of live European wild rabbits (Oryctolagus cuniculus) are unavoidable initial steps for immunization by vaccination against viral hemorrhagic disease (VHD) and myxomatosis as a management tool aimed at enhancing wild rabbit populations. We investigated the short‐term effects of vaccination campaigns against VHD and myxomatosis on the survival of 206 European wild rabbits in a Spanish population. While no effect was observed on the survival of adult rabbits, young and subadult rabbits (P < 0.001) had higher mortality rates during the first week after handling than in the subsequent 3 weeks. The hazard rate of death from disease was inversely correlated with body condition (P < 0.001) during the first week. Vaccination increased the hazard rate of death due to disease during the first 7 days post‐handling, although this detrimental effect was higher in young rabbits (P = 0.012) and modulated by body condition (P = 0.004). The hazard rate of dying from predation during the first week was higher for males than females (P = 0.023) and in subadults compared to young rabbits (P = 0.004). Body condition was inversely related to the predation hazard rate (P = 0.002). Our results suggest that vaccination campaigns had a short‐term negative impact caused by the stress of handling in addition to the detrimental effects of vaccination against VHD and myxomatosis. Future studies should consider this negative impact to assess the true efficacy of vaccination campaigns in wild populations.

Rabbit haemorrhagic disease (RHD) and rabbit haemorrhagic disease virus (RHDV): a review

“…Indeed, administration to wild rabbits implies capturing and handling of rabbits which by being a stress factor might increase the mortality rates [221]. In addition, this would need to be performed systematically since induced-immunity lasts no longer than 1 year [222] and efficacy has been shown to be dependent on several physiological parameters of the individuals [223].…”

Survival of translocated wild rabbits: importance of habitat, physiological and immune condition

“…This result suggests that myxomatosis is probably still an important cause of mortality in wild rabbit populations, although its real impact is hard to assess because most of the symptoms of the disease are chronic or sub-acute and predators often kill sick rabbits that would have died of the disease anyway (Temple, 1987;Calvete et al, 2002). Myxomatosis and RHD are endemic diseases in the Iberian Peninsula and periodic outbreaks occur with an epidemiological pattern characterized by high antibody prevalence in adult individuals (Calvete et al, 2002;Calvete et al, 2004b). Cabezas et al (2006) showed for the same individuals in the present study that 95% of rabbits were seropositive against myxomatosis after vaccination (79% were seropositive before vaccination), although variations in the values of antibody concentrations were found.…”

“…The impact of myxomatosis and RHD on wild populations suggests that these diseases also significantly affect the success of translocations (Calvete et al, 2004a(Calvete et al, , 2004bMoreno et al, 2004). The great majority of translocation programmes include the systematic immunization of all rabbits by vaccination and long-term survival of translocated rabbits could be associated with their antibody concentration at the time of release, which may subsequently decline (Fullagar, 1977;Ross et al, 1989;Sim´on et al, 1993).…”

Estudio preliminar sobre la abundancia y distribución de la perdiz roja (Alectoris rufa Linnaeus, 1758) en el Parque Natural Sierra de Mariola (Alicante-Valencia)

“…Este papel como presa clave, junto a la aparición de las enfermedades víricas del conejo: Mixomatosis: enfermedad vírica inoculada en Francia en 1952, para controlar las poblaciones de esta especie, y Enfermedad Hemorrágica Vírica o VHD, detectada en España por primera vez en 1988 (Calvete et al, 2004), de la enfermedad vírica del conejo, ha podido provocar que, en numerosas regiones de España la presión cinegética se redirigiera hacia la perdiz, incrementando la sobreexplotación sus poblaciones (Blanco-Aguiar et al, 2004;Blanco-Aguiar, 2007).…”