Exposure to Coxiella burnetii in Wild Lagomorphs in Spanish Mediterranean Ecosystems.

Coxiella burnetii is an important zoonotic pathogen of worldwide distribution that can infect a wide range of wild and domestic species. The European wild rabbit (Oryctolagus cuniculus) can play a role as a reservoir for this bacterium in certain epidemiological scenarios, but, to date, a very limited numbers of large-scale serosurveys have been conducted for this species worldwide. Although exposure in hare species has also been described, C. burnetii in Iberian hare (Lepus granatensis) has never been assessed. Here, we aimed to determine the seroprevalence and risk factors associated with C. burnetii exposure in wild lagomorphs in the Mediterranean ecosystems of southern Spain. Between the 2018/2019 and 2021/2022 hunting seasons, blood samples from 638 wild lagomorphs, including 471 wild rabbits and 167 Iberian hares, were collected from 112 hunting grounds distributed across all eight provinces of Andalusia (southern Spain). The overall apparent individual seroprevalence was 8.9% (57/638; 95% CI: 6.8-11.4). Antibodies against C. burnetii were found in 11.3% (53/471; 95% CI: 8.4-14.1) of the wild rabbits and 2.4% (4/167; 95% CI: 0.1-4.7) of the Iberian hares. Seropositive animals were detected for 16 (14.3%; 95% CI: 7.8-20.8) of the 112 hunting grounds tested and in all the hunting seasons sampled. A generalized estimating equations model showed that the geographical area (western Andalusia) and presence of sheep were risk factors potentially associated with C. burnetii exposure in wild lagomorphs. A statistically significant spatial cluster (p < 0.001) was identified in the south-west of Andalusia. Our results provide evidence of moderate, endemic and heterogeneous circulation of C. burnetii in wild lagomorph populations in Spanish Mediterranean ecosystems. Risk-based strategies for integrative surveillance programs should be implemented in these species to reduce the risk of transmission of the bacterium to sympatric species, including humans.

Fatal leptospirosis in endangered Barbary macaques (Macaca sylvanus) kept in captivity: Assessing the role of sympatric rodents.

Between December 2020 and January 2021, an outbreak of acute mortality in endangered Barbary macaques (Macaca sylvanus) kept in captivity was detected in a zoo in Spain. The main findings observed in the two fatally affected animals at post-mortem evaluation were jaundice, renal tubular necrosis and interstitial nephritis. Leptospira spp. infection was confirmed by real time PCR (qPCR) in different tissues in both individuals. Analyses of secY gene from a positive individual showed 100% homology with a previously published sequence corresponding to Leptospira interrogans serovar Copenhageni. Free-living sympatric brown rats (Rattus norvegicus) from the affected zoo were also analyzed, and showed a prevalence and seroprevalence of Leptospira spp. of 18.2% (4/22; 95% CI: 2.1-34.3) and 41.9% (26/62; 95% CI: 29.7-54.2), respectively. We detected seropositive sera to five different serovars of Leptospira spp. (Copenhageni, Grippotyphosa, Pomona, Canicola and Hardjo) in the rodent population, with L. Copenhageni being the predominant one. This study describes for first time an outbreak of fatal leptospirosis in captive non-human primates in Europe. Our results show that Barbary macaques, an endangered species, are highly susceptible to Leptospira spp. infection, with sympatric wild rodents being the most likely reservoir animals involved in transmission in this outbreak. Our results suggest that rodent control could be an effective measure for minimizing exposure to Leptospira spp. in zoological collections. Given the potential implications for conservation, animal and public health, non-human primates and rodents should be included in surveillance programs for Leptospira spp. in zoos.

Hepatitis E Virus Infections in Free-Ranging and Captive Cetaceans, Spain, 2011-2022.

Epidemiologic surveillance of hepatitis E virus in over 300 free-ranging and captive cetaceans in waters off Spain revealed extensive exposure to this pathogen. We suggest the persistent and widespread presence of hepatitis E in the marine environment off the coast of Spain may be driven by terrestrial sources of contamination.

Spatiotemporal monitoring of myxomatosis in European wild rabbit (Oryctolagus cuniculus) in Spanish Mediterranean ecosystems.

A long-term active epidemiological surveillance programme was conducted to determine seroprevalence to myxoma virus (MYXV), infection prevalence and spatiotemporal patterns and factors associated with MYXV circulation in wild rabbits (Oryctolagus cuniculus) in Spanish Mediterranean ecosystems. A total of 2376 animals were sampled over four study periods: 2009-2012 (P1), 2012-2015 (P2), 2015-2018 (P3) and 2018-2021 (P4). Antibodies against MYXV were detected by a commercial indirect ELISA in 59.9% (1424/2376; 95% CI: 58.0-61.9) of wild rabbits. At least one seropositive animal was detected on 131 (96.3%) of 136 game estates sampled. MYXV infection was confirmed by PCR in 94 of 1063 (8.8%; 95% CI: 7.3-10.7) wild rabbits. Circulation of the novel recombinant MYXV (ha-MYXV) was not found in wild rabbits analysed during P4. Five statistically significant spatiotemporal clusters of high MYXV seroprevalence were identified using a Bernoulli model: one in P2 and four in P3. A generalized linear mixed model (GLMM) analysis identified sampling season (autumn), age (adult and juvenile), outbreaks of myxomatosis in the month prior to sampling, mean annual temperature, humidity and seropositivity to rabbit haemorrhagic disease virus as factors potentially linked with MYXV seropositivity. GLMM analysis identified outbreaks of myxomatosis in the month prior to sampling, MYXV seropositivity and presence of lesions compatible with myxomatosis as factors associated with MYXV infection. The results indicate high exposure, widespread but non-homogeneous distribution, and endemic circulation of MYXV in wild rabbit populations in southern Spain during the last decade. Prevalence of antibodies against MYXV showed fluctuations both within the year and over the study periods, revealing variations in the immunity of wild rabbit populations in Mediterranean ecosystems that could increase the risk of MYXV re-emergence in immunologically naïve populations. The present study highlights the importance of long-term surveillance to better understand the epidemiology of MYXV in wild lagomorphs.

Monitoring of hepatitis E virus in zoo animals from Spain, 2007-2021.

Hepatitis E virus (HEV, family Hepeviridae) is an important emerging and zoonotic pathogen. In recent decades, the number of human cases of zoonotic hepatitis E has increased considerably in industrialized countries and HEV has been detected in an expanding range of mammal species. Although domestic pigs and wild boar are considered the main reservoirs of zoonotic HEV genotypes, the role of other susceptible animals in the epidemiology of the virus is still poorly understood. A large-scale, long-term study was carried out (1) to assess HEV exposure in captive zoo animals in Spain and (2) to determine the dynamics of seropositivity in individuals that were sampled longitudinally during the study period. Between 2007 and 2021, serum samples from 425 zoo animals belonging to 109 animal species (including artiodactyls, carnivores, perissodactyls, proboscideans and rodents) were collected from 11 different zoological parks in Spain. Forty-six of these animals at seven of these zoos were also longitudinally sampled. Anti-HEV antibodies were detected in 36 (8.5%; 95% CI: 5.8-11.1) of 425 sampled zoo animals. Specific antibodies against HEV-3 and HEV-C1 antigens were confirmed in ELISA-positive animals using western blot assay. Two of 46 longitudinally surveyed animals seroconverted during the study period. Seropositivity was significantly higher in carnivores and perissodactyls than in artiodactyls, and also during the period 2012-2016 compared with 2007-2011. HEV RNA was not detected in any of the 262 animals that could be tested by RT-PCR. To the best of the author's knowledge, this is the first large-scale, long-term surveillance on HEV in different orders of zoo mammals. Our results indicate exposure to HEV-3 and HEV-C1 in zoo animals in Spain and confirm a widespread but not homogeneous spatiotemporal circulation of HEV in captive species in this country. Further studies are required to determine the role of zoo species, particularly carnivores and perissodactyls, in the epidemiology of HEV and to clarify the origins of infection in zoological parks.

Outbreak of Yersinia pseudotuberculosis in capybaras (Hydrochoerus hydrochaeris) kept in captivity.

On January 2020, an outbreak of acute mortality was detected in the capybara (Hydrochoerus hydrochaeris) population kept in the Cordoba Zoo Conservation Center (CZCC) in Spain. Morbidity and mortality rates were 71%, and the fatality rate was 100%. Macroscopic examination revealed multifocal nodular lesions with fibrinonecrotic exudate in lungs and mesenteric lymph nodes. Microscopic lesions were characterized as severe acute fibrinopurulent bronchopneumonia and generalized vascular changes. Cultures and biochemical analyses yielded Yersinia pseudotuberculosis (YPT). This species was confirmed by both PCR and MALDI-TOF. This report describes the first outbreak of fatal YPT infection in zoo animals in Spain and confirms that capybaras are highly susceptible to this pathogen, which could be of animal health, conservation, and public health concern. Future studies are warranted to determine potential sources of YTP infection in zoos to prevent future cases in susceptible species, including humans.