2. Universidad Cardenal Herrera-CEU

Cryptosporidiosis is an infectious enteric disease caused by species (some of them zoonotic) of the genus Cryptosporidium that in many countries are under surveillance. Typing assays critical to the surveillance of cryptosporidiosis typically involve characterization of Cryptosporidium glycoprotein 60 genes (gp60). Here, we characterized the gp60 of Cryptosporidium suis from two samples—a human and a porcine faecal sample—based on which a preliminary typing scheme was developed. A conspicuous feature of the C. suis gp60 was a novel type of tandem repeats located in the 5′ end of the gene and that took up 777/1635 bp (48%) of the gene. The C. suis gp60 lacked the classical poly-serine repeats (TCA/TCG/TCT), which is usually subject to major genetic variation, and the length of the tandem repeat made a typing assay incorporating this region based on Sanger sequencing practically unfeasible. We therefore designed a typing assay based on the post-repeat region only and applied it to C. suis-positive samples from suid hosts from Norway, Denmark, and Spain. We were able to distinguish three different subtypes; XXVa-1, XXVa-2, and XXVa-3. Subtype XXVa-1 had a wider geographic distribution than the other subtypes and was also observed in the human sample. We think that the present data will inform future strategies to develop a C. suis typing assay that could be even more informative by including a greater part of the gene, including the tandem repeat region, e.g., by the use of long-read next-generation sequencing.

Sarcoptic mange is a widely distributed disease, with numerous potential hosts among domestic and wild animals. Nowadays it is considered a neglected re-emergent infection in humans. As a difference with domestic pigs, and even with several clinical cases reported in some European countries, it seems that Eurasian wild boars (Sus scrofa) have a low susceptibility to clinical mange. However, because of a case of confirmed transmission from Spanish ibex (Capra pyrenaica) to wild boar in the province of Tarragona, we planned a large-scale ELISA survey in the neighboring Valencian Community (SE Spain). We compared 419 wild boar sera from different management systems (fenced vs. open game estates), different ages (piglets, juveniles, and adults), with different behaviour (gregarious females of all ages and male piglets vs. solitary juveniles and adult males), from areas with different wild boar densities, different wild ruminant densities and different sarcoptic mange epidemiologic situations. The whole prevalence of antibodies against sarcoptic mange in the tested wild boars was 10.5%. No significant differences were found when comparing fenced and free ranging wild boars, males and females, gregarious vs. solitary individuals or among different ages. However, wild boar density was a relevant factor. In areas with a hunting bag of <1 wild boar/km2, considered as a low density of suids, the seroprevalence was 2.94%, but rose to 11.52% in high density districts, constituting a significant difference (p = 0.037). Low wild boar populations would act as a protective factor (OR 0.233; p = 0.049) against coming into contact with the mite. The wild ruminant densities or their sarcoptic mange status did not show any effect on wild boars seroprevalence against this disease. These results reinforce the suggested host-taxon Sarcoptes scabiei specificity and the independence of host-species foci.

The protozoans Giardia duodenalis and Cryptosporidium spp. are common causes of gastrointestinal disease in humans and animals. While both are commonly documented in domestic animals, few studies have analysed their presence in wildlife. To assess the prevalence of both parasites in wild boar (Sus scrofa) in the Valencian Community (eastern Spain), 498 wild boar faecal samples were collected from 2018 to 2022. Cryptosporidium spp. was detected by performing a nested PCR targeting a 578 bp sequence of the small subunit ribosomal RNA gene (SSU rRNA), followed by sequencing and phylogenetic analysis. For G. duodenalis, a qPCR amplifying a fragment of 62 bp from the SSU rRNA was employed. Positive samples were genotyped for glutamate dehydrogenase and β-giardin genes. Different epidemiological factors were considered potential modulating variables in the transmission of both parasites. G. duodenalis prevalence was 1.20%, while Cryptosporidium spp. prevalence reached 21.7%. Coinfection was observed in 0.2%. Genotyping of G. duodenalis isolates only detected genotype E. Two species of Cryptosporidium spp. were identified: Cryptosporidium scrofarum and Cryptosporidium suis. The results of this study demonstrate that the exposure to Cryptosporidium spp. in wild boars is high, particularly among young individuals belonging to the Typical Mediterranean climate. Moreover, the probability of infection is dependent on both the season and the density of wild boars. On the other side, exposure to G. duodenalis seems scarce and is influenced, in turn, by the climate. Both Cryptosporidium species detected in the present study have been reported in humans. Due to wild boar increasing in number and their colonisation of urban and peri-urban areas, this could represent an inherent health risk for the human population.

The Iberian hare (Lepus granatensis) is a popular small game species in the Iberian Peninsula, and it has never been reported to be affected by sarcoptic mange. An adult female Iberian hare with overt skin lesions on forelimbs and ventral thorax, suggestive of sarcoptic mange, was culled in Quart de les Valls municipality in the Valencian Community, Spain, in 2019. Skin scrapings were digested in 10% KOH solutions to confirm the presence of mites. Ten Sarcoptes microsatellite markers were used to characterize the genetic structure of mites obtained from the hare, and from sympatric and allopatric wild rabbits (Oryctolagus cuniculus) and red foxes (Vulpes vulpes). A total of 56 alleles were counted across the 10 microsatellite loci. Six private alleles were found at four loci (Sarms 33, 38, 41, 45). The multivariate analysis characterized three main clusters, corresponding to mites collected on foxes originating from Catalonia, foxes from Valencia and the hare plus wild rabbits. To our knowledge, this is the first reported case of sarcoptic mange in the Iberian hare. The origin was molecularly traced back to contacts with endemically infected wild rabbits. We encourage further investigations on cross-transmissibility of S. scabiei between wild rabbits and the diverse representatives of Lepus spp.