Rabbit haemorrhagic disease: Cross-protection and comparative pathogenicity of GI.2/RHDV2/b and GI.1b/RHDV lagoviruses in a challenge trial

Calvete, C. ; Mendoza, M. ; Alcaraz, A. ; Sarto, M.P. ; Jiménez-de-Bagüéss, M.P. ; Calvo, A.J. ; Monroy, F. ; Calvo, J.H.

Resumen: European rabbits (Oryctolagus cuniculus) are severely affected by rabbit haemorrhagic disease (RHD). Caused by a lagovirus, the disease leads to losses in the rabbit industry and has implications for wildlife conservation. Past RHD outbreaks have been caused by GI.1/RHDV genotype viruses. A new virus belonging to the GI.2/RHDV2/b genotype emerged in 2010, quickly spreading and replacing the former in several countries; however, limited data are available on its pathogenicity and epidemiological factors. The present work extends these issues and evaluates cross-protection between both genotypes. Ninety-four and 88 domestic rabbits were challenged with GI.2/RHDV2/b and GI.1b/RHDV variant isolates, respectively. Cross-protection was determined by a second challenge on survivors with the corresponding strain. Mortality by GI.2/RHDV2/b was highly variable due to unknown individual factors, whereas mortality by GI.1b/RHDV was associated with age. Mortality in rabbits < 4 weeks old was 84%, higher than previously reported. Cross-protection was not identical between the two viruses because the ratio of mortality rate ratios for the first and second challenges was 3.80 ± 2.68 times higher for GI.2/RHDV2/b than it was for GI.1b/RHDV. Rabbit susceptibility to GI.2/RHDV2/b varied greatly and appeared to be modulated by the innate functionality of the immune response and/or its prompt activation by other pathogens. GI.1b/RHDV pathogenicity appeared to be associated with undetermined age-related factors. These results suggest that GI.2/RHDV2/b may interact with other pathogens at the population level but does not satisfactorily explain the GI.1b/RHDV virus's quick replacement.

Idioma: Inglés

DOI: 10.1016/j.vetmic.2018.04.018

Año: 2018

Publicado en: Veterinary Microbiology 219 (2018), 87-95
ISSN: 0378-1135

Factor impacto JCR: 2.791 (2018)

Categ. JCR: VETERINARY SCIENCES rank: 7 / 141 = 0.05 (2018) - Q1 - T1
Categ. JCR: MICROBIOLOGY rank: 67 / 133 = 0.504 (2018) - Q3 - T2

Factor impacto SCIMAGO: 1.166 - Medicine (miscellaneous) (Q1) - Veterinary (miscellaneous) (Q1) - Microbiology (Q1)

Financiación: info:eu-repo/grantAgreement/ES/INIA/RZ2010-00009-00-00

Tipo y forma: Article (PostPrint)