The occurrence of intestinal nematodes in red foxes in the Western Pomerania

In the period from November 2004 to March 2005 the prevalence of gastro-intestinal nematodes of 165 foxes (Vulpes vulpes L.) from the Pomerania region was examined. These parasites were found in 66.1% of examined foxes. Toxocara canis was the most frequent parasite and was observed in 33.9% of examined animals. Toxascaris leonina was found in 1.2%, Uncinaria stenocephala in 25.5%, Ancylostoma caninum in 6.7 and Trichuris vulpis in 10.3% of the examined foxes.     

Rediscovery of Trichinella spiralis in red foxes (Vulpes vulpes) in Ireland after 30 years of oblivion

OBJECTIVE: To determine whether or not Ireland can be considered as Trichinella-free, after more than 30 years of no reported infections in domestic and sylvatic animals and in humans. METHODS: Samples of muscle tissue from the tongue, masseter, and foreleg of red foxes (Vulpes vulpes) were subjected to artificial digestion and to multiplex-PCR analysis for identifying Trichinella larvae at the species level. RESULTS: Four of 454 examined foxes were positive for larvae (overall prevalence 0.9%). The positive foxes had been collected in Donegal County (one fox; prevalence of 7.7%), Cork County (two foxes; 3.1%), and Waterford County (one fox; 4.2%). All larvae were identified as Trichinella spiralis. CONCLUSIONS: The detection of Trichinella-positive foxes in Ireland is an example of how the lack of infections among domestic animals and humans does not suffice for establishing Trichinella-free status. The results also confirm that the sylvatic cycle can last for tens of years, independently of the existence of a domestic cycle.     

Analysis of the epidemiological factors influencing vulpine trichinellosis in ecologically different regions of Slovakia

INTRODUCTION: In the Slovak Republic, trichinellosis circulates almost exclusively in the sylvatic cycle, with main reservoir host red fox and wild boar and sporadic occurrence of human outbreaks. A detailed study was performed in five ecologically different regions of eastern Slovakia with more profound regard to eco-geographical and anthropogenic influences to natural fox habitat. MATERIAL AND METHODS: In total of 689 red foxes (Vulpes vulpes) hunted in selected regions in 2005/2006 was examined using artificial digestion method. Larvae obtained from infected samples were on the species level characterised using multiplex PCR analysis. RESULTS: The study revealed a total prevalence of 15.6%, with most frequent occurrence of infected foxes in the mountain of the Volovské Vrchy (25.2%) where both human habitation and fox population are very dense. High prevalence rates were found in the Kosická Kotlina Basin (19.6%) with urbanised landscape, concentrated human activities and low fox population and in national park of the High Tatras (15.8%) where the inhabitants and fox population are relatively low. In the remote localities of the Nízke Beskydy Highlands that represent ideal fox habitat free of any human impact, 14.2% of foxes harboured Trichinella larvae. The lowest occurrence of infected foxes (6.9%) was found in agrarian areas of the Vychodoslovenská Nizina Lowland, with relatively low inhabitants and fox population density. In all localities Trichinella britovi was the most important etiological agent of sylvatic trichinellosis.     

Endoparasites of red fox (Vulpes vulpes) in the Slovak Republic with the emphasis on zoonotic species Echinococcus multilocularis and Trichinella spp.

Summary  Due to specific geographical localization, climatic and geomorphologic conditions, several serious parasitic diseases circulate in the territory of the Slovak Republic that makes this area an ideal model territory of the central European red fox system. The red fox is an important reservoir host of parasites, which can be spread to another animals and humans. Our study was aimed at determining the current prevalence of certain parasites in red foxes from the entire territory of the Slovak Republic and identifies some ecological factors influencing their epidemiology. Within the first systematic investigation of red foxes carried out between the years 2000 and 2006 in total 4026 foxes were examined for Echinococcus multilocularis (prevalence 31.1 %) and 4699 foxes were investigated for the presence of Trichinella spp. larvae (10.4 % infected). The results of the next separate study revealed that 83.3 % of 1198 red foxes in the Slovak Republic had coccidian oocysts and helminth eggs in their faeces. Fifteen helminth species including two trematode, four cestode and nine nematode species were detected by coprological examination. Nine of these parasite taxa have zoonotic potential: Capillaria spp. (prevalence 22.4 %), Ancylostoma caninum (18.1 %), Toxocara canis (12.5 %), Taenia spp. (12.2 %), Mesocestoides spp. (5.8 %), Strongyloides stercoralis (1.6 %), Hymenolepis diminuta (0.6 %), Dipylidium caninum (0.4 %) and Opisthorchis felineus (0.3 %). Toxascaris leonina was the most common helminth species found in this survey (42.9 %).     

Parasites of carnivorous mammals in Białowieza Primeval Forest

BACKGROUND: Although the parasitofauna of wild carnivorous mammals in Poland is quite well recognized, there has been only one research carried on this issue so far in Bia?owieza Forest--the last lowland primeval forest of temperate zone in Europe. MATERIAL AND METHODS: Twelve wild and two domestic species of carnivorous mammals are living in Bia?owieza Forest. In our work faeces or intestines of all of them except ermine (Mustela erminea) have been examined and parasites or their eggs (or oocysts) recorded. In total 222 faecal probes from 13 species and 11 intestines of weasels have been investigated. RESULTS: All species of examined carnivorous mammals were infected with parasites. The most infected species has occurred red fox Vulpes vulpes (over 70% infected with parasites) meanwhile only about 30% of otters Lutra lutra were infected. We found at least three protozoan species, one trematode, one tapeworm and nine species of nematodes. Except trematode Alaria alata, all of them are reported for the first time from Bia?owieza Primeval Forest. Oocysts of coccidia have been found in faeces of nine host species, with the highest prevalence (29.4%) in badger. Six species of carnivorous mammals have been occurred infected with trematodes (highest prevalence 42.1% in wolves) and two with tapeworms (Diphyllobothrium latum with the prevalence 2.6% in otter and 31.6% in wolves). All examined host species were infected with nematodes (with prevalence from 14.7% in lynx to 72.7% in red fox). Results of our work should be treated as preliminary researches on the species composition of parasitic fauna invading carnivorous mammals in Bia?owieza Primeval Forest.     

Wild carnivores as source of zoonotic helminths in north-eastern Italy

Summary Two hundreds and sixty red foxes, eighteen badgers and eight stone martens from north-eastern Italy were examined for zoonotic parasites by SCT, with particular attention to Trichinella sp. and Echinococcus multilocularis. No adult worms of E. multilocularis were observed in the intestine of red foxes or mustelids. Out of 223 fox faecal samples analysed by a commercial CA-ELISA, 5.8 % was positive to Echinococcus coproantigens. Trichinella sp. was detected by digestion of muscle in 1.2 % of examined foxes (2/172), but not in mustelids (0/11). Toxocara canis, responsible for human toxocarosis, resulted to be common in fox population (48.5 %). This parasite was found both in young (53.3 % of cubs and 61.9 % of sub-adults) and in adult animals (42.7 %). Other zoonotic parasites as Uncinaria stenocephala (52.3 %) and Trichuris vulpis (0.4 %) were detected in fox populations.     

Anaplasma phagocytophilum: an emerging tick-borne pathogen in Hungary and Central Eastern Europe

Anaplasma phagocytophilum (formerly Ehrlichia phagocytophila, Ehrlichia equi and Anaplasma phagocytophila) is the causative agent of granulocytic ehrlichiosis (anaplasmosis) in humans, horses, sheep, cattle, dogs and cats. In the present study, 452 European sheep ticks (Ixodes ricinus) collected from 100 red foxes (Vulpes vulpes) in Hungary were tested for the pathogen, as 112 pools each containing five or fewer ticks from one fox. Six of the pools, representing ticks from six different foxes, were found infected in the PCR-based test employed. This is the first time that A. phagocytophilum has been reported in Hungary. A summary of the information available from Central Eastern Europe on the prevalence of A. phagocytophilum in ticks, its seroprevalence in humans, and the number of human cases of granulocytic ehrlichiosis known in the region is presented.     

Red fox and tick-borne encephalitis (TBE) in humans: can predators influence public health?

Analysing datasets from hunting statistics and human cases of tick-borne encephalitis (TBE), we found a positive correlation between the number of human TBE cases and the number of red fox (Vulpes vulpes). Time lags were also present, indicating that high numbers of red fox in 1 y translated into high numbers of human TBE cases the following y. Results for smaller predators were mixed and inconsistent. Hares and grouse showed negative correlations with human TBE cases, suggesting that they might function as dilution hosts. Combining our findings with food web dynamics, we hypothesize a diversity of possible interactions between predators and human disease - some predators suppressing a given disease, others enhancing its spread, and still others having no effect at all. Larger-sized predators that suppress red fox numbers and activity (i.e. wolf, Canis lupus; European lynx, Lynx lynx) were once abundant in our study area but have been reduced or extirpated from most parts of it by humans. We ask what would happen to red foxes and TBE rates in humans if these larger predators were restored to their former abundances.     

Zoonotic Bartonella species in fleas and blood from red foxes in Australia

Bartonella are arthropod-borne, fastidious, Gram-negative, and aerobic bacilli distributed by fleas, lice, sand flies, and, possibly, ticks. The zoonotic Bartonella species, Bartonella henselae and Bartonella clarridgeiae, which are the causes of cat scratch disease and endocarditis in humans, have been reported from cats, cat fleas, and humans in Australia. However, to date, there has been no report of B. henselae or B. clarridgeiae in Australian wild animals and their ectoparasites. B. henselae and B. clarridgeiae were detected in fleas (Ctenocephalides felis) from red foxes (Vulpes vulpes), an introduced pest animal species in Australia, and only B. clarridgeiae was detected in blood from one red fox. Phylogenetic analysis of the ribosomal intergenic spacer region revealed that the B. henselae detected in the current study were related to B. henselae strain Houston-1, a major pathogenic strain in humans in Australia, and confirmed the genetic distinctness of B. clarridgeiae. The identification and characterization of Bartonella species in red foxes in the Southwest of Western Australia suggests that red foxes may act as reservoirs of infection for animals and humans in this region.     

Red fox (Vulpes vulpes) a new host species for acanthocefalan Moniliformis moniliformis (Bremser, 1811) in Poland

Acanthocephalan Moniliformis moniliformis is a parasite of rodents, rarely also reported from carnivorous mammals. One female specimen of this parasite has been found in the small intestine of red fox Vulpes vulpes. It is the first report about this species invading the red fox in Poland.     

Raccoon dog (Nyctereutes procyonoides)--the new host of Echinococcus multilocularis in Poland

The alimentary canals of 9 species of domesticated or wild animals were examined for the presence of E. multilocularis. The tapeworm was found in 9 red foxes (Vulpes vulpes) out of 155 examined (5.8%) and in 2 raccoon dogs (Nyctereutes procyonoides) of 25 examined (8.0%). Our studies proved that in Poland the raccoon dog can also be infected with E. multilocularis.     

Endemic alveolar echinococcosis in Southern Belgium?

Until now, Belgium has been considered as a low-risk country for alveolar echinococcosis. However it was recently demonstrated by necropsy series that, in some parts of southern Belgium (Wallonia), up to 51% of the red foxes (Vulpes vulpes) may be infected by E. multilocaris. The authors, working in a university hospital in southern Belgium, described in 2002 the first autochthonous Belgian case of hepatic alveolar echinococcosis. More importantly, in 2004, they diagnosed three other patients with alveolar echinococcosis. One underwent surgical resection, but two others had bilateral pulmonary involvement at time of definite diagnosis. Palliative albendazole therapy was initiated. These patients had been diagnosed with hepatic mass from unknown origin for several months. The previous experience with the first case allowed the authors to consider and to confirm alveolar echinococcosis diagnosis, made by pathology and/or serological tests and imaging. These four patients with alveolar echinococcosis were living either in the Liege or the Luxembourg province. Considering the high prevalence of E. multilocaris infection of red foxes and the recent increase of the fox population due to rabies vaccination in southern Belgium, and also the presence of E. multilocaris infection of red foxes in northern Belgium, it is likely that not only Wallonia, but also maybe the whole Belgium, may face endemic alveolar echinococcosis in the next years.     

Wild and domestic animals as permanent Trichinella reservoir in Poland

BACKGROUND: [corrected] Since Owen first described Trichinella as a human patogen in 1835, the number of organisms comprising this genus has grown dramatically. This etiological agent of human trichinellosis shows worldwide distribution in domestic and/or sylvatic animals. MATERIAL AND METHOD: The aim of the presented paper was to determine the distribution of Trichinella species in wild animals such as red foxes, wolves, wild boars, and domestic pigs in Poland. Muscle samples from diaphragm and forelegs were collected from animals killed by hunters. Muscle larvae were recovered from the muscle after artificial digestion and identified at the species level by RAPD, PCR-RPLF and multiplex PCR. RESULTS: Of 75 nematode isolates from red foxes: (Vulpes vulpes), 50 resulted as T. britovi, 6 T. spiralis, 6 were mixed infections of these two species. Fifteen Trichinella isolates remained unidentified. Of 97 nematode isolates from wild boars (Sus scrofa), 21 resulted as T. britovi, 69 T. spiralis, 2 were mixed infections of these two species. Five Trichinella isolates remained unidentified. Of 6 examined wolves (Canis lupus) killed in the Bieszczady region, 3 animals were positive against T. britovi. Of 6 examined raccon dogs (Nyctereutes procyonoides) from Pomorskie region, 2 animals were positive against T. spiralis. Of 21 nematode isolates from domestic pigs, 1 resulted as T. britovi and 21 as T. spiralis. Up to date, two Trichinella species are detected as the etiological agents of epidemiology among domestic and wildlife animal in Poland: T. britovi is the dominant species in red foxes and T. spiralis is the dominant species in wild boars and domestic pigs.     

The epidemiology of Echinococcus granulosus in Great Britain. V. The status of subspecies of Echinococcus granulosus in Great Britain

Twenty-five years ago Williams and Sweatman suggested that in Great Britain there are two subspecies of Echinococcus granulosus--E. granulosus granulosus and E. granulosus equinus. Echinococcus granulosus granulosus does not mature either in foxes or in horses: E. granulosus equinus will mature in either. The prepatent period of E. granulosus granulosus in the definitive host is about 42 days while that of E. granulosus equinus is about 70 days. Each subspecies has a characteristic morphology. More recently, in the course of seven experiments, dogs, red foxes (Vulpes vulpes crucigera), arctic foxes (Alopex lagopus), badgers (Meles meles), domestic ferrets and domestic cats have been infected with protoscoleces derived from hydatid cysts of human, equine and ovine hosts from different regions of England and Wales. Transmissions to horses and sheep were always succeeded by the development of viable hydatid cysts; transmissions to dogs and foxes, by the development of gravid adults. The prepatent period in both dogs and foxes was invariably about 70 days (or longer) and the morphology of all the adult parasites in these definitive hosts was characteristic of E. granulosus equinus. All the evidence derived from these experiments supports the view that there is, in Great Britain, but one subspecies of E. granulosus. That one subspecies is E. granulosus equinus. It infects dogs, red foxes, arctic foxes (experimentally), cats (experimentally), humans, sheep, goats, horses, donkeys, pigs, cattle, roe deer and reindeer (in Scotland). Attempts to transmit E. granulosus to badgers and domestic ferrets were unsuccessful. Of 123 cats infected with protoscoleces of horse origin, one gravid adult parasite was recovered from one animal.     

Potential risk of zoonotic infections in recreational areas visited by Sus scrofa and Vulpes vulpes. Case study--Wolin Island, Poland

The relation between intestinal parasite prevalence in wild boars and red foxes and the sanitary condition of the soil in recreational estates were determined. The analysis was made based on 36 samples of boar faeces and 22 samples of fox faeces, collected in their habitat as well as 60 samples of soil from two recreational areas. Two methods were used for faecal samples--flotation and direct faecal smear; and flotation in NaNO3 for soil samples examination. Zoonotic nematode eggs were recovered from 25.5% of boar faecal samples; they were Ascaris suum (22.2%) and Trichuris suis (5.6%). Other parasites found were: Metastrongylus sp. (69.4%), Oesophagostomum sp., Strongyloides sp. (36.6%) and Physocephalus sp. (8.6%) as well as coccidia (69.4%). In fox faeces, zoonotic nematode eggs were recovered from 31.8% of samples, and they were Toxocara canis (27.2%) and Ancylostoma caninum (18.2%). Tapeworm eggs were found in 36.4% of samples including Taenia sp. (22.7%). The presence of Uncinaria stenocephala (45.5%), Capillaria sp. (36.4%), Trichuris vulpis (4.5%) and coccidia (40.1%) was also detected. It was shown that both, flotation and faecal smear, as mutually complementary should be used for higher rate of detection of parasites in faeces. No eggs of zoonotic helminths in soil from recreational areas were found despite these areas were accessible to wild animals and pets. This could be explained by characteristics of the soil (loose sand soil) as well as by behaviour of the parasite hosts in the examined areas.     

The prevalence of Toxocara canis (Werner, 1782) in dogs and red foxes in north-west Poland

One of the most dangerous parasites, not only for carnivores but also for human being is Toxocara canis. It is presented very commonly all over the world, so spread its into the humans organisms, especially childrens is very easy. The aim of this study was to determine the prevalence of Toxocara canis in dogs and red foxes in area of north-west Poland. The dog coproscopy was provided according to Willis-Schlaff method. Post mortem examination of red foxes was conducted according to Eckert and Amman (1990), Eckert et al. (1991) and Ewald (1993). In examined area dogs were infected with Toxocara canis from 2.67 to 55% (Table 1). The highest prevalence was observed in Gorzów Wielkopolski in its neighborhood (villages) and in urban places. The lowest extensity (2.67%) was determined in urban area of S?upsk city. In examined forest regions the prevalence of Toxocara canis in red foxes was 43% (Table 2). To sum up, north-west Poland is a region where Toxocara canis is common, both in domesticated and wild environment. There should be provided regular monitoring of this zoonozis as well as pharmacological treatment of dogs.     

The etiology of sylvatic trichinellosis in Switzerland]

Three Trichinella strains from Swiss wild foxes (Vulpes vulpes) were tested in crossbreeding experiments with Trichinella spiralis, T. nativa and T. nelsoni using white mice as laboratory animals. The results demonstrated that T. nelsoni Britov et Boev 1972 is the etiologic agent of sylvatic trichinellosis in Switzerland. Former isolations of these species were successful in materials from East and South Africa, USSR (Republics of Tadzhikistan, Turkmenia and Kazakhstan) and Bulgaria. The area of T. nelsoni covers probably the whole southern part of the Old World up to the 48th degree of northern latitude.     

Isolation of Brucella microti from mandibular lymph nodes of red foxes, Vulpes vulpes, in lower Austria

From the mandibular lymph nodes of wild red foxes (Vulpes vulpes) hunted in the region of Gmünd, Lower Austria, two gram-negative, oxidase- and urease-positive, coccoid rod-shaped bacteria (strains 257 and 284) were isolated. Cells were fast growing, nonmotile, and agglutinated with monospecific anti-Brucella (M) serum. Both strains were biochemically identified as Ochrobactrum anthropi by using the API 20NE test. However, sequencing of the 16S rRNA and recA genes clearly identified strains 257 and 284 as Brucella spp. Further molecular analysis by omp2a/b gene sequencing, multilocus sequence typing and multilocus variable number tandem repeats analysis revealed Brucella microti, a recently described Brucella species that has originally been isolated from diseased common voles (Microtus arvalis) in South Moravia, Czech Republic in 2000. Our findings demonstrate that B. microti is prevalent in a larger geographic area covering the region of South Moravia and parts of Lower Austria. Foxes could have become infected by ingestion of infected common voles.     

Vulpes vulpes: a possible wild reservoir for zoonotic filariae

Foxes (Vulpes vulpes, n = 132) killed during the hunting seasons 2005-2006 in Central Italy (Tuscany region) were examined in order to investigate the possible importance of this animal as a wild reservoir for zoonotic filariae. In each specimen adult worms of Dirofilaria immitis and hematic microfilariae were searched for. Species identification was performed by morphology, morphometry, the Barka staining technique applied to pulmonary and splenic blood smears, and, finally, by molecular diagnostics -- polymerase chain reaction (PCR) and sequencing. Twenty-three subjects (17.4%) proved to be positive for filarial parasites. Infection by Acanthocheilonema was more widespread than by Dirofilaria. Briefly, 8 foxes harbored mature adults of D. immitis; two of them (25%) also had microfilariae that in one case were mixed with the microfilariae of D. repens. Twelve subjects had microfilariae of Acanthocheilonema reconditum, and 3 harbored microfilariae of A. dracunculoides. Molecular diagnostics confirmed all results. Our findings, drawn by the examination of a few microliters of blood obtained from foxes approximately <2 years of age, support the hypothesis that this animal may be an abundant source of infection for ticks that transmit Acanthocheilonema parasites and for mosquitoes that act as vectors for dirofilarial nematodes. Therefore foxes, contributing to the parasite circulation in areas where dogs usually undergo prophylactic treatment, have to be considered an important wild reservoir for filarial parasites that can be transmitted to companion animals and people.     

Experimental La Crosse virus infection of red fox (Vulpes fulva), raccoon (Procyon lotor), opossum (Didelphis virginiana), and woodchuck (Marmota monax)

Susceptibility to infection, resulting viremia and antibody responses, and potential to provide infectious blood meals for Aedes triseriatus were determined and compared for the red fox (Vulpes fulva), raccoon (Procyon lotor), and opossum (Didelphis virginiana) exposed to La Crosse (LAC) virus transmitted by mosquitoes, Ae. triseriatus. Woodchucks (Marmota monax) were infected with LAC virus by needle and syringe. All 5 red foxes became viremic following the bite of a single LAC virus-infected female Ae. triseriatus. Maximum viremia titers were at or above the threshold of infection for Ae. triseriatus in 4 of 5 red foxes for 1-3 days. Biological transmission of LAC virus from infected red foxes to chipmunks (Tamias striatus) was accomplished by Ae. triseriatus. Neutralizing antibody titers in red foxes peaked between day 13 and 27 and were still detectable 3 months post-infection. Woodchucks appear to be efficient amplifiers of LAC virus. Three of 4 inoculated woodchucks became viremic. Maximum viremia titers were consistently above the experimentally determined threshold of infection for Ae. triseriatus. Raccoons and opossums were not as susceptible to LAC virus infection as were red foxes or woodchucks. Only 1 of 5 raccoons became viremic. The viremia titer was low and was detected on only 1 day. Four of 5 raccoons developed LAC virus-neutralizing antibody titers, however. None of the opossums became viremic and only 2 developed LAC virus-neutralizing antibody titers.