Naturally occurring orthopoxviruses: potential for recombination with vaccine vectors - PubMed (original) (raw)

Naturally occurring orthopoxviruses: potential for recombination with vaccine vectors

T Sandvik et al. J Clin Microbiol. 1998 Sep.

Abstract

Orthopoxviruses are being increasingly used as live recombinant vectors for vaccination against numerous infectious diseases in humans, domestic animals, and wildlife. For risk assessments and surveillance, information about the occurrence, distribution and ecology of orthopoxviruses in western Europe is important but has mainly been based on serological investigations. We have examined kidneys, lungs, spleens, and livers of Norwegian small rodents and common shrews (Sorex araneus) for the presence of orthopoxvirus DNA sequences by PCR with primers complementary to the viral thymidine kinase (TK) gene. PCR amplicons were verified as orthopoxvirus specific by hybridization with a vaccinia virus TK-specific probe. A total of 347 animals (1,388 organs) from eight locations in different parts of Norway, collected at different times of the year during 1993 to 1995, were examined. Fifty-two animals (15%) from five locations, up to 1,600 km apart, carried orthopoxvirus DNA in one or more of their organs, most frequently in the lungs. These included 9 of 68 (13%) bank voles (Clethrionomys glareolus), 4 of 13 (31%) gray-sided voles (Clethrionomys rufocanus), 3 of 11 (27%) northern red-backed voles (Clethrionomys rutilus), 16 of 76 (21%) wood mice (Apodemus sylvaticus), and 20 of 157 (13%) common shrews. The previous isolation of cowpox virus from two clinical cases of infection (human and feline) at two of the locations investigated suggests that the viruses detected are cowpox and that some of the virus-carrying small mammalian species should be included among the cowpox virus natural reservoir hosts in Scandinavia and western Europe.

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Figures

FIG. 1

FIG. 1

Nucleotide sequence of the vaccinia virus TK gene and its flanking regions (17). The positions of the PCR primers are shown in boldface and are underlined. The _Bsp_DI (position 465) and _Eco_RI (position 498) cleavage sites are underlined. The start codon for translation is shown in boldface and italics.

FIG. 2

FIG. 2

Agarose gel showing TK-PCR amplicons of VV-WR, CPV-BR, and ectromelia virus (strain Moscow) and restriction fragments from _Bsp_DI and _Eco_RI digestion of the amplicons. Lanes: 1, VV-WR; 2, CPV-BR; 3, ectromelia virus (strain Moscow); M, 1-kb size marker.

FIG. 3

FIG. 3

(A) Agarose gel showing TK-PCR amplicons of VV-WR, CPV-BR, and ectromelia virus (strain Moscow). (B) Southern hybridization blots of the agarose gel in panel A when hybridized with the 226-bp vaccinia virus TK-specific labeled probe. Lanes: 1, VV-WR; 2, CPV-BR; 3, ectromelia virus (strain Moscow); 4, fowlpox virus; 5, negative control (H2O); M, 1-kb marker.

FIG. 4

FIG. 4

(A) Agarose gel showing examples of TK-PCR amplicons from small mammal tissue samples. (B) Southern hybridization blots of the same samples from panel A. Lanes: 1 and 2, VV-WR-positive control, with 10 and 1 μl of amplicon, respectively; 3, negative control (H2O); 4 and 5, lung DNA from two Sorex araneus animals; 6, 7, and 8, DNA from liver, spleen, and kidney, respectively, from three Clethrionomys glareolus animals; M, 1-kb size marker.

FIG. 5

FIG. 5

Trapping locations of wild rodents and common shrews. Local names and counties are given. 1, Masi, Finnmark; 2, Tromsø, Troms; 3, Bygstad, Sogn og Fjordane; 4, Austrheim, Hordaland; 5, Kalandsvatn, Hordaland; 6, Hardangervidda National Park; 7, Søgne, Vest-Agder; 8, Kongsvinger, Hedmark.

References

    1. Amegadzie B Y, Sisler J R, Moss B. Frame-shift mutations within the vaccinia virus A-type inclusion protein gene. Virology. 1991;186:777–782. - PubMed
    1. Baxby D. Is cowpox misnamed? Br Med J. 1977;1:1379–1381. - PMC - PubMed
    1. Baxby D. Poxvirus hosts and reservoirs. Arch Virol. 1977;55:169–179. - PubMed
    1. Baxby D, Ashton D G, Jones D M, Thomsett L R. An outbreak of cowpox in captive cheetahs: virological and epidemiological studies. J Hyg. 1982;89:365–372. - PMC - PubMed
    1. Baxby D, Bennett M. Cowpox virus. In: Webster R G, Granoff A, editors. Encyclopedia of virology. London, United Kingdom: Academic Press; 1994. pp. 261–267.

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