Moisés Gonzálvez

Norway rats ( Rattus norvegicus ) and black rats ( Rattus rattus ) are the definitive hosts and primary reservoirs of Angiostrongylus cantonensis , an emerging zoonotic parasite globally considered the leading cause of human eosinophilic meningoencephalitis. A. cantonensis surveillance in rodent populations in Europe has been conducted in restricted geographic areas, but large‐scale epidemiological studies remain lacking. We aimed to determine the prevalence of A. cantonensis in rat populations across mainland Spain and assess the spatial distribution of the parasite. A prospective cross‐sectional study was conducted between 2022 and 2025, comprising a total of 407 individuals (244 Norway rats and 163 black rats). During necropsy, cardiopulmonary tissues were systematically collected and examined under a stereomicroscope for the presence of adult A. cantonensis . In addition, a nested molecular technique was performed to confirm the taxonomic identity of adult nematodes visualized during stereomicroscopic examination. Cardiopulmonary dissection revealed that only two individuals out of 407 (0.5%; 95% CI: 0.1–1.8), both black rats ( Rattus rattus ) from Valencia (eastern mainland Spain), harboured adult nematodes morphologically compatible with A. cantonensis in the heart. These parasites were successfully sequenced and molecularly confirmed as A. cantonensis , exhibiting 100% nucleotide identity with A. cantonensis sequences previously reported from gastropods in Spain and the USA. These findings evidence a localized distribution of A. cantonensis in rats across mainland Spain. Nevertheless, conducting continuous One Health surveillance of A. cantonensis in Europe is essential to fully understand the epidemiology of this parasite and to assess the associated potential public health risks across the continent.

Background: Equine Infectious Anemia (EIA) is a notifiable disease caused by Equine Infectious Anemia Virus (EIAV), with major sanitary and economic importance for equids worldwide. There is limited and outdated information on the circulation of EIAV in many European countries. In the present study, we aimed to assess virus exposure in different equid species in Western Europe. Methods: Between 2011 and 2023, a cross-sectional study was conducted to investigate the seroprevalence of EIAV in 1676 equids (1444 horses, 106 donkeys and 126 mules/hinnies) from four European regions: Andalusia (Southern Spain; n = 808), Catalonia (Northeastern Spain; n = 437), Southeastern United Kingdom (UK; n = 209), and Ireland (n = 222). Results: None of the analyzed equines tested positive for antibodies against EIAV (0%; 95 %CI: 0.0–0.18), indicating limited virus exposure of the equid populations from these European regions. Conclusions: This finding is consistent with the low EIAV circulation previously reported in Western Europe and the few official EIA outbreaks recorded in the region during the last decade. To the best of the author’s knowledge, this serosurvey represents the first investigation assessing EIAV exposure in equids from Ireland and the UK. Our results not only provide novel epidemiological evidence for the four European regions assessed but also reinforce the effectiveness of surveillance strategies and control measures implemented by European countries, in accordance with national and international regulations, to successfully limit EIAV circulation.

Introduction: Leishmaniosis is a sand fly‐borne zoonosis mainly caused by Leishmania infantum in Europe. Exposure to this protozoan has been widely reported in many domestic and wild species. However, epidemiological surveys evaluating the circulation of L. infantum in zoo‐kept animals remain limited. This large‐scale study aims to evaluate the seroprevalence of L. infantum in zoo‐kept species in Spain as well as alterations in serum protein levels in L. infantum ‐seropositive individuals, to identify potential risk factors associated with L. infantum exposure, and to assess the dynamics of seropositivity in animals longitudinally sampled during the study period. Methods: Between 2007 and 2023, serum samples from 429 zoo‐kept animals belonging to 72 species were collected in nine zoos in Spain using convenience sampling. Additionally, 29 of these individuals from six of the tested zoos were also longitudinally sampled. Results: Anti‐ L. infantum antibodies were detected in 22 (5.1%; 95% CI: 3.0–7.2) of the 429 animals using an in‐house ELISA, as well as in 13.9% (10/72) and 66.7% (6/9) of the species and zoos tested, respectively. Serum protein electrophoresis analyses revealed that polyclonal gammopathy was the most common alteration in L. infantum ‐seropositive individuals. Three animals longitudinally surveyed seroconverted throughout the study period. The multivariate analysis identified the family Canidae as a risk factor for L. infantum exposure. Conclusions: Our results indicate a moderate, widespread and endemic circulation of L. infantum in zoo‐kept animals from Spain, which may be of animal health, conservation, and public health concern. Surveillance programs and control measures should be implemented in zoos to minimise the exposure of these species to Leishmania spp., particularly in hotspot areas.

We report mortality in bearded vultures ( Gypaetus barbatus ) associated with highly pathogenic avian influenza HPAI A H5N1 clade 2.3.4.4b, responsible for the current HPAI panzootic. Between April and May 2022, a total of five bearded vultures from Spain, four free‐ranging and one captive individual, were found dead in their nest or with acute symptoms of disease. Complete necropsies were performed and histopathological, immunohistochemistry and molecular analyses were carried out. The presence of the HPAI H5N1 virus was confirmed in different organs, oropharyngeal and cloacal swabs and feathers from the affected individuals. The complete viral genome was obtained from three of the affected bearded vultures. Phylogenetic analyses revealed that the sequences obtained from the free‐ranging individuals and the captive specimen belonged to the clade 2.3.4.4b and clustered separately. Furthermore, it supports that direct or indirect contact with other sympatric wild birds could be the most likely source of infection. This research highlights the susceptibility of the endangered bearded vulture to HPAI H5N1, thereby contributing to the broader understanding of the virus's host range.