Hepatitis E virus in the endangered Iberian lynx ( Lynx pardinus )

Abstract

Hepatitis E virus (HEV) is an emerging zoonotic pathogen in Europe. In the Iberian Peninsula, wild boar (Sus scrofa) is considered the main wildlife reservoir of HEV. This wild ungulate shares habitat and resources with other potential HEV carriers in Iberian Mediterranean ecosystems, although information about the role of such sympatric species in the HEV epidemiological cycle is still very limited. The aims of the present large‐scale, long‐term study were: (1) to determine the seroprevalence and prevalence of HEV in both free‐living and captive populations of the Iberian lynx (Lynx pardinus), the most endangered felid in the world; (2) to determine potential risk factors associated with HEV exposure in this species and (3) to evaluate the dynamics of seropositivity in longitudinally sampled animals during the study period. Between 2010 and 2021, serum samples from 275 Iberian lynxes were collected in free‐ranging and captive populations across the Iberian Peninsula. Forty‐four of the 275 lynxes were also longitudinally sampled during the study period. A double‐antigen sandwich ELISA was used to test for the presence of antibodies against HEV. A subset of seropositive samples was analysed by Western blot (WB) assay to confirm exposure to HEV. In addition, serum, liver and/or faecal samples from 367 individuals were tested for orthohepevirus RNA by RT‐PCR. A total of 50 (18.2%; 95% CI: 14.1–23.2) of the 275 animals analysed had anti‐HEV antibodies by ELISA. Exposure to HEV was confirmed by WB in most of the ELISA‐positive Iberian lynxes analysed. Significantly higher seroprevalence was found in captive (33.6%) compared to free‐ranging (7.4%) individuals. Within captive population, the GEE model identified ‘age’ (senile, adult and subadult) as risk a factor potentially associated with HEV exposure in the Iberian lynx. Thirteen (29.5%) of 44 longitudinally surveyed individuals seroconverted against HEV during the study period. HEV RNA was detected in the faeces of one (1/364; 0.3%; 95% CI: 0.0–0.8) free‐ranging adult animal sampled in 2021. Phylogenetic analysis showed that the sequenced strain belongs to HEV‐3f subtype and shared a high nucleotide sequence identity (97–99.6%) with human HEV‐3f sequences from Spain and France. To the best of the authors’ knowledge, this is the first survey study on HEV in the Iberian lynx and the first molecular report of HEV‐A infection in free‐ranging felines. Our results indicate high exposure to HEV‐3 in Iberian lynx populations, particularly those kept in captivity. The serological results suggest widespread but not homogeneous circulation of HEV in Iberian lynx populations. Further studies are required to assess the epidemiological role of this endangered species as a potential spillover host of HEV.

Detection of anti-HEV antibodies but no molecular positivity in dogs in the Campania region, southern Italy

“…Although this trend is typical among pets (dogs and cats), the same cannot be said for wildlife, as evidenced by multiple identifications of viral RNA in different matrices. To date, HEV has been identified in the feces of wolves, red foxes, and lynxes and in the cavity transudates of red foxes [ 7 , [27] , [28] , [29] ]. Furthermore, in wild animals, exposure to the virus appears significantly higher, probably due to greater contact with reservoir hosts and therefore a greater possibility of contracting the infection through their ingestion.…”

“…The first was a real-time PCR performed using iTaq Universal Probes Supermix (Bio-Rad) employing the following primers and probes: F 5′-RGTRGTTTCTGGGGTGAC-3′; R 5′-AKGGRTTGGTTGGRTGA-3′; probe 5′-FAM-TGAYTCYCARCCCTTCGC-TAMRA-3′. The thermal conditions included an initial denaturation of 15 min at 95 °C, followed by 40 cycles of denaturation at 95 °C (10 s), annealing at 51 °C (30 s), and extension at 60 °C (20 s) [ 2 , 7 ]. Results were read using a CFX96™ Real-Time PCR Detection System (Bio-rad).…”

“…However, all attempts to detect the virus in blood, feces or liver tissue have failed [ 5 , 6 ]. The situation is different among wild carnivores, where molecular positivity has occasionally been reported in addition to significant serological prevalences [ 7 ]. All these aspects of the complex epidemiological cycle of HEV have been highlighted in Italy [ 8 ].…”

Is Hepatitis E Virus a Neglected or Emerging Pathogen in Egypt?

“…In Spain, a high seroprevalence (18.2%) was recorded in free-ranging and captive Iberian lynx (Lynx pardinus) and the captive cats were more seropositive than the free-ranging ones [108]. Interestingly, HEV RNA was detected in the stool of one cat and phylogenetic analysis revealed that the isolated strain belonged to HEV genotype 3, subtype 3f, with a high homology sequence identity with human HEV strains in this area [108]. In Egypt, no studies have been conducted on cats.…”

Monitoring of Hepatitis E Virus in Wild Lagomorphs in Spanish Mediterranean Ecosystems

“…Tese species are considered an important source of food for humans, especially in rural areas and usually for self-consumption, as rabbit meat is one of the most nutritional white meats [16]. Over the last decade, circulation of HEV has been confrmed in sympatric wildlife from this European region, such as wild boar (Sus scrofa) [17], red deer (Cervus elaphus) [18], and also the Iberian lynx (Lynx pardinus) [19], whose staple prey is the European wild rabbit. Even though active HEV infection was not found in wild lagomorphs in southern Spain [20], only a single local study has assessed HEV exposure in a limited number of wild lagomorphs in the Iberian Peninsula (southern Portugal), detecting seropositivity [21].…”