Toxoplasma gondii and Trichinella infections in wild boars (Sus scrofa) from Northeastern Patagonia, Argentina

Abstract

Wild boar (Sus scrofa) was introduced in many countries of the world and is recognized as carrier of many infectious diseases. Wild game meat consumption is recognized as a source of transmission of Toxoplasma gondii and Trichinella spp. The aim of the present study was to evaluate the prevalence of antibodies to T. gondii and Trichinella spp. in freerange wild boars in Northeastern Argentine Patagonia. Between 2014 and 2018, 144 blood samples and 423 muscle samples from 423 carcasses were collected. To detect T. gondii IgG, 144 sera were processed by an immunofluorescent antibody test, and to detect anti-Trichinella IgG, 125 sera and 304 muscle juice samples were processed by ELISA. Detection of first stage larvae in muscle was performed by artificial digestion. A total of 423 wild boars muscle samples were negative to Trichinella spp. by artificial digestion. Antibodies to Trichinella spp. were detected in 2.4% (3/125) of serum samples and in 1.64% (5/304) of meat juice samples. Antibodies to T. gondii infection were detected in 12.5% (18/144) of the serum samples. This is the first study to reveal the presence of antibodies to T. gondii in wild boars from Argentina. The present results suggest that consumption of raw or undercooked wild boar meat could represent a potential source risk for toxoplasmosis in humans and that Trichinella spp. is infrequent and/or that it circulates in low burdens among wild boars in Northeastern Patagonia.

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

“…Many studies have been carried out in recent years on the prevalence of Toxoplasma gondii antibodies in free-range and bred boar in many regions of the world, including Japan [42], the United States [27,28,30,43], Argentina [6], Brazil [44], China [45,46], and Korea [35,47]. Numerous studies have also been conducted in Europe.…”

“…The European Food Safety Authority (EFSA) has recognized toxoplasmosis as a parasitic zoonosis with the highest prevalence in humans [5]. It is also classified by the FAO-WHO as belonging to the "top ten" of food-borne parasites [6,7]. T. gondii infections are common in many species of farm and non-domesticated animals sourced for food.…”

“…Wild boar also search for food at landfills, city parks or suburban areas [23]. The species shows high adaptability to changing climatic and environmental conditions [6] and high reproductive potential [27]. Wild boar serve as reservoirs of numerous viruses, bacteria and parasites [25], which can be a potential source of human, farm and companion animals diseases [27,28,29].…”

“…Wild boar are the intermediate host of T. gondii, although it is unclear whether infection occurs primarily by ingestion of tissue cysts from the meat of prey, through scavenging, or by ingestion of oocysts from the environment [6]. Carcass residues left on the hunting grounds may also be a source of infection.…”

“…As an omnivorous species, wild boar is considered a bioindicator of environmental pollution with T. gondii [35,37]. 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].…”