Wisconsin State Parks

Parasitol Res. 2006 Nov;99(6):694-9.

Anaplasma phagocytophilum in central and western Wisconsin: a molecular survey.

Michalski M1, Rosenfield C, Erickson M, Selle R, Bates K, Essar D, Massung R.

Author information

  • 1Department of Biology and Microbiology, University of Wisconsin Oshkosh, 800 Algoma Boulevard, Oshkosh, WI 54901, USA. michalsk@uwosh.edu


Anaplasma phagocytophilum is an obligate intracellular bacterium that is transmitted to humans through the bite of Ixodes spp. ticks, and causes a febrile disease known as human granulocytic anaplasmosis. The presence of A. phagocytophilum in Wisconsin white-tailed deer blood and in deer ticks was assessed using PCR and DNA sequencing.

Sampling sites in the western part of the state (Buffalo County) and central region (Waushara, Waupaca, and Green Lake counties) were used. In Buffalo County, 5.6% of deer and 8.9% of ticks were infected.

At Hartman Creek State Park (Waupaca County), 11.5% of ticks were infected, while the observed prevalence in deer from counties to the south of the park (Waushara and Green Lake) reached 19-26%.

Based on 16S rRNA sequences, A. phagocytophilum strains associated and not associated with human infections were identified. Furthermore, two novel A. phagocytophilum variants were found in deer blood samples.

Transmission of Lyme disease has been documented in both the Western and Central regions we sampled, and the presence of A. phagocytophilum in naturally occurring tick populations could present an additional risk of disease to humans that enter tick habitats.

PMID: 16738890 [PubMed - indexed for MEDLINE]


J Med Entomol. 2001 Jan;38(1):33-8.

Ixodes scapularis (Acari: Ixodidae): abundance and rate of infection with Borrelia burgdorferi in four state parks in Wisconsin.

Paskewitz SM1, Vandermause M, Belongia EA, Kazmierczak JJ.

Author information

  • 1Department of Entomology, University of Wisconsin, Madison, WI 53706, USA.


Four state parks located in Lyme disease endemic regions of Wisconsin were surveyed for the presence of Ixodes scapularis Say during May and June of 1998 by drag sampling along hiking trails. Nymphal abundance varied between parks, with the average number of nymphs encountered in 1 h ranging from 6.2 +/- 3.8-47.1 +/- 36.3 (mean +/- SD).

Questing nymphs were tested for the presence of Borrelia burgdorferi by culture in BSK medium and 7-12% was found to be infected. The average risk of encountering an infected nymph (entomologic risk index) ranged from 0.5 to 5.2 infected nymphs per hour. The highest entomological risk index was recorded from a small island park in northwestern Wisconsin during the last week in May (8.0 infected nymphs per hour).

These results indicate a lower risk for human Lyme disease exposure in Wisconsin state parks in comparison with highly endemic areas of the northeastern United States.

PMID: 11268688 [PubMed - indexed for MEDLINE]