Occurrence of selected zoonotic food-borne parasites and first molecular identification of Alaria alata in wild boars (Sus scrofa) in Italy

Abstract

Wild boar is a source of human infections with zoonotic pathogens, including food-borne parasites. With the aim of a characterization of the human exposure risk, a survey on wild boars intended for human consumption was planned, selecting three pathogens, Toxoplasma gondii, Alaria alata, and Trichinella spp., as markers of meat infection. Diaphragm muscle samples from 100 wild boars hunted in Piedmont region (Northern Italy) in two hunting seasons (2015-2016) were collected. Concerning T. gondii, a combined approach of antibody detection and molecular techniques with genotyping was performed. For the detection of A. alata and Trichinella spp., the larva migration technique and the magnetic stirrer method were employed, respectively; in addition, molecular confirmation of the morphological identification of the recovered specimen was performed. Anti-T. gondii antibodies were found in meat juice samples (43.3%) and T. gondii DNA (type II) was detected in three animals (7.1%) out of 42 seropositive examined. In none of the sampled wild boars (0%), Trichinella spp. larvae were found, whereas one animal (1%) scored positive to A. alata mesocercariae. The molecular diagnosis proved the morphological identification of the trematode. This is the first finding of A. alata in Italian wild boar population. The present study confirmed the role of wild boars as a source of parasitic zoonotic diseases and thus the risk derived for humans posed by the consumption of game meat. Considering the zoonotic implications, the results underline the importance of monitoring and surveillance of zoonotic parasites in Italian wild boar populations.

Prevalence of <i>Toxoplasma gondii</i> antibodies in wild boar (Sus scrofa) from Strzałowo Forest Division, Warmia and Mazury Region, Poland

“…The presented study confirmed a high prevalence of T. gondii antibodies in the investigated animals (48%, n=50), which makes Poland one of the countries with the highest percentage of T. gondii seropositive wild boar. Similar results were obtained in Spain (38.4%, MAT) [48], Italy (43.3%, ELISA) [32], Sweden (49.5%, ELISA) [49], and the Czech Republic (39.6%, ELISA) [9]. The percentage of seropositive wild boar was lower in several studies conducted in the Czech Republic (15.4% and 26.2%) [31,37], Spain (23.8%) [50] and Sweden (28.6%) [29], as well as in France (16.8% and 17.6%) [4,51], Switzerland (6.7%) [2], The Netherlands (24.4%) [39], Slovakia (8.1%) [3], Finland (33%) [52], Portugal (20.6%) [1], Denmark (27.7%) [53], Greece (5.2%) [25], Romania (16%) [54], Italy (14%) [55], Latvia (33.2%) [56] and Estonia (24%) [38].…”

“…The increase in their population size observed in recent years increases the risk of wild boar contact with people and pigs, and thus the risk of pathogen transmission, including zoonotic pathogens such as T. gondii [30]. The consumption of raw or undercooked meat is considered an important route of infection for humans [1,31,32,33,34]. However, the source of infection is difficult to determine [35], and varies depending on the populations tested (e.g.…”

“…T. gondii infection in wild boar is of limited clinical importance [39]; it is typically asymptomatic and chronic, where animals show specific antibodies and have tissue cysts [6], but clinical congenital toxoplasmosis has also been reported [40]. The occurrence of T. gondii infections in wild boar is important from the perspective of public health protection, as increased consumption of venison, including meat obtained from wild boars, is considered a risk factor for T. gondii infection in humans [32].…”

Toxoplasma gondii infection in meat-producing small ruminants: Meat juice serology and genotyping

“…The present survey, aimed at estimating the presence of T. gondii in small ruminants' meats consumed in Italy, revealed seroprevalence values lower than those previously reported in sheep J o u r n a l P r e -p r o o f Journal Pre-proof (59.3%) and goats (41.7%) bred in Northern Italy [6]. In the study area, T. gondii showed to be widely spread also in other domestic [11,12] and wild animals [13][14][15]. Moreover, compared to the previous epidemiological survey [6] mostly focusing on adult meat producing sheep and dairy goats, in the present study both adult and young sheep and goats were sampled since a large proportion of lambs and kids are slaughtered in Italy (respectively 90.3% and 86%) (data obtained from the National Institute of Statistic, ISTAT, http://dati-censimentoagricoltura.istat.it/).…”

Factors affecting the spread of parasites in populations of wild European terrestrial mammals

“…Some parasites settle in the muscle tissue of hosts, e.g., Alaria spp., Trichinella spp., Spirometra sp., and Toxoplasma spp. ; thus, they can be ingested by humans eating raw or inadequately cooked meat (Dmitric et al 2018;Gazzonis et al 2018;Kołodziej-Sobocińska et al 2016c). It is important to carry out parasitological monitoring of wild animals, especially those that are hunted or live near human settlements, and therefore have the potential to become a threat to humans.…”