D. Antolová

Dirofilariosis in Slovakia - a new endemic area in Central Europe

SummaryThe first systematic research on canine dirofilariosis in Slovakia started in February 2007. In total 287 dogs of various age, sex, breeds, and utilization from southern Slovakia were examined within the study until September 2007. Microfilariaemia was detected in 99 (34.5 %) blood samples. Histochemical staining and PCR approach were used for Dirofilaria species identification. Dirofilaria repens was confirmed in all infected dogs; it occurred in 92 (32.1 %) dogs as a single infection and in 6 (2.1 %) dogs in mixed infection with Dirofilaria immitis. For the first time both species were detected in Eastern Slovakia. Outdoor keeping and age higher 3 years become evident as important risk factors. Male individuals and dogs with long hair were significantly more frequently infected when compared with females and short hair breeds.The present study revealed the occurrence of highly endemic area of dirofilariosis in Slovakia and certified that climatic conditions in the country are favourable for development of the parasite and for further spread of this zoonotic infection.

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

SummaryDue 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 %).

The First Finding of Echinococcus multilocularis in Dogs in Slovakia: An Emerging Risk for Spreading of Infection

Alveolar echinococcosis, caused by the metacestode Echinococcus multilocularis, is a zoonosis of public health significance. Apart from red foxes, other carnivore species can also serve as definitive hosts of this parasite. This study aimed to determine the occurrence of E. multilocularis in dogs in the Slovak Republic and identify risk factors for acquiring the infection. Out of 289 dogs examined, E. multilocularis was detected in eight samples (2.8%). Positive results were observed in shepherd dogs (12.5%), guard dogs (7.1%), hunting dogs (2.4%) and in one dog with unknown usage (2.5%). Catching rodents and feeding with raw viscera were confirmed to be the most important risk factors for E. multilocularis infection. On the contrary, the way of dog use, frequency of going to the rural areas, the age and gender of animals seem not to be risk factors for infection. No significant association was observed between the positivity of dogs coming from high endemic or non‐endemic regions. This is the first report of E. multilocularis in dogs in the Slovak Republic that confirms substantial contribution of dogs to the transmission of the tapeworm in this territory and urges the necessity of prophylactic measures for dog owners.

Neospora caninum, potential cause of abortions in dairy cows: the current serological follow-up in Slovakia.

Neosporosis is considered to be a contributing risk factor for abortions in dairy cows and other farm animals and has negative economic impact on their breeding. In respect of the rapid spread of neosporosis in herds throughout the world, our aim was to detect the prevalence of anti-Neospora antibodies in cows post-abortion (PA) (PA Group n=716) and in cows without any reproduction problems (Control Group n=247) on large breeding farms from Eastern Slovakia. The overall mean seropositivity in PA Group (20.1%) was significantly higher (p<0.0001) in comparison with the Control Group (2.3%), and this demonstrates the causal dependency of abortions on neosporosis. On farms from south-east region, 15.6% of cows were seropositive on average ranging from 7.8% to 25.8% in different districts. In the northern region, significantly (p=0.0002) higher 26.2% mean seropositivity was detected. The seroprevalence in different districts ranged from 2.9% to 39.4%. In the PA Group a high seropositivity to infectious bovine rhinotracheitis (41.5%) and sporadic occurrence of Q-fever, leptospirosis and chlamydiosis was also detected. From 11 Toxoplasma-seropositive cows, only one animal was simultaneously positive to Neospora. The relatively high prevalence rate in cows warrants the attention and a need of surveillance in Slovak herds. A better knowledge of epidemiology of this etiological agent and the mechanisms of its transmission may help in the introduction of more effective preventive and control measures.

The role of wild boars (Sus scrofa) in circulation of trichinellosis, toxocarosis and ascariosis in the Slovak Republic

SummaryWild boars (Sus scrofa) can play a significant role in circulation and maintenance of certain parasites in the environment. The aim of this study was to determine the seroprevalence of trichinellosis, toxocarosis and ascariosis in wild boars hunted in the Slovak Republic in 2003 and 2004. Anti-Trichinella antibodies were detected in 1.3 % out of 1035 wild boars investigated. No significant differences were observed regarding the positivity of wild boars according to age and sex in both years. The examination of 1173 wild boars for anti-Toxocara antibodies revealed 7.2 % seropositive individuals. Anti-Ascaris antibodies were detected in 6.1 % out of 411 animals examined. Both, anti-Trichinella and anti-Toxocara antibodies were determined in 0.6 % cases. Presence of anti-Trichinella and anti-Ascaris antibodies was recorded in 0.8 % animals. Concurrent infection caused with Toxocara and Ascaris was observed in 1.5 % individuals. This study concentrates on the role of wild boars in circulation and on the maintenance of trichinellosis, toxocarosis and ascariosis in the Slovak Republic.

Occurrence and genetic characterization of Toxoplasma gondii in naturally infected pigs

The protozoan Toxoplasma gondii is an obligate intracellular parasite that infects a wide range of warm-blooded vertebrates. The data about the occurrence of toxoplasmosis in slaughter pigs in the Slovak Republic are still missing. The aim of our study was to estimate the prevalence of toxoplasmosis in pigs from Slovakia during the period of 2006–2010 by ELISA and PCR methods. In sera of 970 slaughter pigs, 2.16% seropositivity to T. gondii was detected. In tissue samples of seropositive pigs the presence of T. gondii DNA was confirmed. In six monitored Slovak regions the seropositivity varied between 1.11 and 3.48%. The statistically significant differences were recorded between the Košice and Prešov region. The seroprevalence of toxoplasmosis in sows (4.26%) was two times higher than that in slaughter pigs (2.06%) (OR = 2.12; 95% CI = 0.48–9.36). Presence of Toxoplasma gondii in tissues of seropositive pig isolates was confirmed by TGR1E and B1 genes and analysis of DNA polymorphism at SAG2 and ROP1 genes revealed the presence of virulent strain of genotype I in 85.7% of infected pigs and an avirulent strain (genotype II) in 14.3% of pigs.

Humoral immune response of mice infected with low doses of Trichinella spiralis muscle larvae.

Serological techniques are frequently used to detect parasite status and to monitor epidemiology and disease prevalence in important reservoir hosts of zoonotic diseases. Small mammals present the most important link in the epidemiological chain in the spread of trichinellosis. In experimental studies, high infective doses are used to provoke strong immune response of laboratory animals. Wild animals, however, could be infected with very low numbers of Trichinella larvae. The aim of this work was to reveal the size of infective doses that can evoke an adequate immune response with detectable level of specific antibodies in mice. Sixty inbred (Balb/c) mice were infected with 50 L1 and 60 outbred (ICR) mice were infected with 5 L1 T. spiralis. The total larval burdens (TLB) in the intestinal and muscle phases, reproductive capacity index (RCI), and the kinetics of development of specific antibodies by iELISA with different conjugates were determined. In the first 10 days post infection (dpi), more adults were found in the intestines of inbred mice. In both mice strains, the first muscle larvae were observed at 20 dpi. The RCI was significantly higher in outbred mice. Sero-conversion of IgM antibodies was detected at 30 dpi. The IgG antibodies appeared at 40 dpi in inbred mice, and at 50 dpi in outbred mice. Using a polyvalent conjugate, the earliest sero-conversion was recorded at 30 dpi. Antibody levels increased until the end of the experiment (80 dpi). Our results support the suitability of ELISA in large epidemiological surveys to detect low-level infection in naturally infected small mammals, and are useful in epidemiological studies of the sylvatic circulation of trichinellosis to determine likely modes of transmission.

Influence of anthelmintic baits on the occurrence of causative agents of helminthozoonoses in red foxes (Vulpes vulpes)

SummaryRed fox (Vulpes vulpes) presents major wildlife reservoir of parasitozoonoses, transmissible to humans and domestic animals. The study was aimed to find out the effect of anthelmintic baits on the occurrence of Echinococcus multilocularis and other intestinal helminths in red foxes. In two bait areas (B1 and B2) 20 baits per km2 were distributed monthly between August 2004 and April 2005. Fox fecal samples were collected in both bait areas and two control areas (C1 and C2) between August 2004 and August 2005. In bait area B1 the decrease of parasite species number, decrease of their prevalence and prevalence of E. multilocularis was observed. No significant decline was observed in bait area B2, probably due to consumption of baits by wild boars. Bait distribution represents the possibility of reduction of environmental contamination with parasites and their propagation stages. Especially on the periphery of towns and villages and in recreational areas it seems to be suitable way of human health protection.

Echinococcus multilocularis in musk rat (Ondatra zibethicus): the first finding of the parasite in naturally infected rodent in the Slovak Republic

SummaryInfection with the larval stage of Echinococcus multilocularis was diagnosed in musk rat (Ondatra zibethicus) in the Slovak Republic. At necropsy, massively enlarged liver with numbers of abscess-like lesions up to 1.5 cm in diameter was found. Histological examination shoved the presence of typical multivesicular cysts with multiple protoscoleces and typical laminated layer. Polymerase chain reaction confirmed the diagnosis. According to our knowledge, this is the first documentation of Echinococcus multilocularis in naturally infected rodent in territory of the Slovak Republic.

Occurrence of Echinococcus multilocularis in red foxes from the Carpathian Regions of Slovakia and Poland

The extensive distribution of Echinococcus multilocularis cestode from endemic alpine areas to the parts of Central Europe has been recorded in recent years. The first confirmed finding of E. multilocularis in Slovakia was recorded in 1999 in the area adjacent to the Polish border. At present, this serious zoonosis occurs almost across the whole territory of Slovakia. The occurrence of these tapeworms in red foxes (Vulpes vulpes) at the border regions of Slovakia and Poland has been monitored. In these districts, out of 152 faecal samples examined, 36.2% were positive for the coproantigen-ELISA. With the sedimentation and counting technique the prevalence of E. multilocularis in red foxes was up to 38.8%. The examination of foxes from neighbouring districts revealed worm burden ranging from 1–15,000 specimens, but the majority of animals harboured medium number of tapeworms. In the Small Carpathian and Sub-Carpathian regions of Poland, out of 65 samples examined, 13.8% were coproantigen positive. Using the small intestine scraping method only 6.1% prevalence of E. multilocularis in red foxes was determined, mostly with a high worm burdens over 1,000 specimens. The results suggest possible transborder transmission of E. multilocularis, the causative agent of serious alveolar echinococcosis.