Abstract
One thousand one hundred and fifty-one free-living foxes (Vulpes vulpes) from different parts of Sweden were investigated. Totally 19.6 % were infected with trichinella. Infected foxes were found in all counties except the geographically isolated island of Gotland. In the different counties 6–48 % of investigated foxes were infected.
Trichinella was more common in old foxes than in young, 40 % and 11 %, respectively. Regarding male and female, however, the frequency was the same.
The number of trichinella per g of muscle varied between 0.05 and 200. Less than 1.0 trichinella larva per g muscle was established in 27.3 % of the foxes, between 1 and 49.9 trichinella larvae in 69.3 % and 50 or more trichinella larvae per g muscle in 3.4 % of the foxes. The number of trichinella larvae per infected fox was roughly the same in both sexes as well as in different age groups.
The potential danger of transmitting trichinella from foxes and other carnivores to swine and man is pointed out.
The high frequency of trichinella in foxes, 19.6 %, was compared to the very low frequency in swine, 0.00018 %, and in man, 0.00003 %.
Keywords: Trichinella spiralis, fox, swine, man, prevalence
Sammanfattning
1151 fritt levande rävar (Vulpes vulpes) från olika delar av Sverige undersöktes. Av dessa var 19,6 % infekterade med Trichinella. Infekterade rävar forekom i alia landskap utom på Gotland. I de olika länen var 6–48 % av de undersökta rävarna infekterade.
Hos gamla rävar var trichinos vanligare än hos unga, 40 % resp. 11 % var infekterade. Däremot var trikiner lika vanliga hos han- som honrävar.
Antalet trikiner per gram muskulatur varierade melian 0,05–200. Mindre än 1,0 trikin per gram muskulatur påvisades hos 27,3 % av rävarna, melian 1 och 49,9 trikiner hos 69,3 % och över 49,9 trikiner per gram muskulatur hos 3,4 % av rävarna. Antalet trikiner per individ var i stort lika hos de båda könen och även inom olika aldersgrupper.
Den potentiella risken för spridande av trichinos från rävar och andra carnivorer till svin och människa påpekas. Den höga frekvensen trikinfall hos rävar, 19,6 %, jämföres med de mycket låga frekvenserna hos svin, 0,00018 % och hos människa, 0,00003 %.
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References
- Borg, K.: Personal communication, National Veterinary Institute, Stockholm 1978.
- Clausen B., Henriksen Sv. Aa. The prevalence of Trichinella spiralis in foxes (Vulpes vulpes) and other game species in Denmark. Nord. Vet.-Med. 1976;28:265–270. [PubMed] [Google Scholar]
- Ekstam M. Trikinos. (Trichinosis) Svensk Vet.-Tidn. 1964;16:11–17. [Google Scholar]
- Freeman, R. S.: Leveå heisimato ja Trikiini luonnonvaraisissa ketuissa suomessa. (Broad fish tape-worm and trichina worm in wild red foxes in Finland). Finsk Vet.-T. 1964, 7–8, 279–282.
- Gould, S. E.: Trichinosis in Man and Animals. Charles C. Thomas 1970, Springfield, Illinois.
- Hauge S. Trikinosens epidemiologi i Norge. (The epidemiology of trichinosis in Norway) Medlemsbl. norske Vet.-Foren. 1969;21:325–331. [Google Scholar]
- Hülphers G., Henricson T. Undersökningar på förekomst av infektionsämnen och trikiner i råttor. (Studies on the occurrence of microbes and Trichinella in rats) Svensk Vet.-T. 1943;48:197–210. [Google Scholar]
- Iversen, Mr. Trikinosens utbredelse og bekjempelse i Norge. (The occurrence and controlling of Trichinella in Norway). Norsk Vet.-T. 1948, 60, 303–309.
- Lehmensick, R.: Einige Daten über die Epidemiologie der Trichinellose in West-Deutschland (Bundesrepublik). (Some information of the epidemiology of trichinosis in West-Germany). Wiadomosci parazytologiczne T. XVI, 1970, No. 1. Proc. second int. conf. on trichinellosis, Wroclaw, June 26–28, 1969. [PubMed]
- Madsen, H.: The distribution of Trichinella spiralis in sledge dogs and wild mammals in Greenland (Under a global aspect). Meddelelser om Grønland 1961, bd 159 nr. 7.
- Sluiters J. E., Ruitenberg E. J., Vermculen C. J. Vorslag over onder-zoekingen naar het voorkommen van Trichinella spiralis in Nederland. (Studies on the occurrence of Trichinella spiralis in the Netherlands) T. Diergeneesk. 1972;97:1386–1393. [Google Scholar]