The study, led by Taner Gürel of the Samsun Veterinary Control Institute together with Şinasi Umur of Ondokuz Mayıs University, set out to fill a gap in molecular epidemiological data for Turkish wild boar populations. Wild boars occupy a pivotal position in the sylvatic cycles of Sarcocystis, Toxoplasma gondii, and Neospora caninum, three cyst-forming parasites of the phylum Apicomplexa that infect both animals and, in some cases, humans. Because wild boar populations have expanded dramatically across Europe and Anatolia, and because their meat is increasingly consumed as game, understanding what parasites these animals carry has direct implications for food safety, veterinary medicine, and public health.

To detect the parasites, the team combined classical parasitological techniques with a battery of molecular assays. Muscle tissue samples were first subjected to artificial digestion, a method that liberates cysts from meat fibers, and to histopathological examination to look for the characteristic sarcocysts embedded in muscle. The researchers then deployed a multiplex polymerase chain reaction targeting the mitochondrial cytochrome c oxidase subunit I gene, known as cox1, alongside a conventional PCR targeting the 18S ribosomal RNA gene to identify and differentiate Sarcocystis species. For the other two parasites, they used species-specific PCRs: one amplifying the 529 base pair repetitive element of Toxoplasma gondii, a target prized for its sensitivity because it is repeated hundreds of times in the parasite genome, and another targeting the NC5 region of Neospora caninum.

The results were unambiguous for Sarcocystis. Sarcocystis miescheriana was detected in 92 percent of the sampled animals, making it by far the dominant species in the population. Notably, the zoonotic species Sarcocystis suihominis, which can infect humans who eat undercooked pork or wild boar meat, was not found in any of the samples. That absence is reassuring from a food safety standpoint, though the authors caution that continued surveillance is warranted. Phylogenetic analysis of the cox1 sequences obtained from the Turkish isolates placed them close to European strains of S. miescheriana, consistent with the picture of a parasite lineage circulating widely among wild suids across the continent. The 18S rRNA sequence generated in the study has been deposited in GenBank under accession number PV104359.

Co-infections emerged as a defining feature of the population. Fifty-six percent of the wild boars harbored at least two of the three parasite species, and 28 percent carried all three simultaneously. Such high rates of mixed infection reflect the overlapping transmission routes of these parasites: Sarcocystis miescheriana cycles between pigs and canids, with dogs and other carnivores shedding sporocysts that contaminate the environment and are ingested by intermediate hosts; Toxoplasma gondii is transmitted both through oocysts shed by cats and through tissue cysts in meat; and Neospora caninum, whose definitive hosts are canids, is a major cause of abortion in cattle. A wild boar foraging in a contaminated landscape can readily pick up all three pathogens over its lifetime.

To identify risk factors for infection, the researchers applied multivariable logistic regression adjusted for age and sex. Adult age emerged as a significant predictor of Toxoplasma gondii infection, with adult animals showing roughly 3.77 times the odds of infection compared with younger boars, a statistically significant association. A similar but non-significant trend was observed for Neospora caninum, with an adjusted odds ratio of 3.21. Sex was not a significant predictor for either parasite. Triple infections were numerically more common in older animals, a pattern consistent with cumulative environmental exposure over time, although this trend did not reach statistical significance. The age effect fits the biology of these parasites: animals that live longer encounter more contaminated soil, water, and prey, and once infected with tissue cyst-forming protozoa they typically remain infected for life.

The detection of Toxoplasma gondii DNA in half of the sampled boars carries particular public health weight. Toxoplasmosis is one of the most common zoonotic infections worldwide, and while healthy adults usually experience mild symptoms, the parasite can cause severe disease in immunocompromised individuals and in fetuses when a woman acquires a primary infection during pregnancy. Game meat is an increasingly recognized route of exposure, and cases of ocular toxoplasmosis following wild game consumption have been documented in the medical literature. The 529 base pair repetitive element sequences generated in this study have been deposited in GenBank under accession numbers PV133829 through PV133831, adding to the genetic record of the parasite in the region.

Neospora caninum, detected in 38 percent of the animals, is less often a direct human health concern but is economically significant in livestock. The parasite is a leading cause of abortion and neonatal mortality in cattle worldwide, and wildlife reservoirs are thought to contribute to its persistence and spread. Previous surveys in other countries have found antibodies against N. caninum in feral swine and non-carnivorous wildlife, and the Turkish study adds molecular confirmation of the parasite’s presence in wild boar tissues from the region. The finding reinforces the idea that wild boars, which share habitats with livestock and are scavenged upon or hunted by canids, participate in the epidemiology of a parasite that costs the dairy industry substantially each year.

The Turkish results align with a growing body of European literature. Molecular studies in Italy, Greece, Latvia, Iran, and China have repeatedly identified Sarcocystis miescheriana as the predominant Sarcocystis species in wild boars, and surveys in Switzerland have documented both Sarcocystis and Toxoplasma in muscles of wild boars destined for human consumption. What distinguishes the new study is its combined assessment of all three parasites in the same animals, its use of both multiplex and conventional PCR platforms, and its formal statistical modeling of age and sex as risk factors. By quantifying co-infection patterns rather than treating each parasite in isolation, the study offers a more realistic picture of the parasite ecology within a single wild population.

The authors conclude that their results update the molecular epidemiology of tissue cyst-forming apicomplexans in Turkish wild boars and reinforce the importance of sustained One Health surveillance at the wildlife-livestock-human interface. As wild boar numbers continue to grow and the popularity of game meat rises, the study serves as a reminder that hunters, processors, and consumers all have a stake in safe handling and thorough cooking of wild game. It also highlights the value of molecular tools, which can distinguish morphologically similar parasite species and reveal co-infections that microscopy alone would miss. For now, the wild boars of Türkiye’s Black Sea coast stand as a vivid example of how much invisible parasite traffic moves through a seemingly healthy wildlife population.

Subject of Research: Molecular prevalence, co-infections, and genetic characterization of Sarcocystis, Toxoplasma, and Neospora parasites in wild boars from Türkiye

Article Title: Molecular Occurrence, Co-infections and Genetic Characterization of Sarcocystis miescheriana, Toxoplasma gondii and Neospora caninum in Wild Boars (Sus scrofa) from Türkiye

Article References: Molecular Occurrence, Co-infections and Genetic Characterization of Sarcocystis miescheriana, Toxoplasma gondii and Neospora caninum in Wild Boars (Sus scrofa) from Türkiye. (n.d.). https://doi.org/10.1007/s11686-026-01397-9

Image Credits: AI Generated

DOI: 10.1007/s11686-026-01397-9

Keywords: Sarcocystis miescheriana, Toxoplasma gondii, Neospora caninum, wild boar, Türkiye, co-infection, molecular epidemiology, PCR, game meat, food safety, One Health, parasitology