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Volume 31, Number 11—November 2025

Dispatch

Neoehrlichia mikurensis in Ticks and Tick-Bitten Persons, Sweden and Finland, 2008–2009

Emilia Hero, Malin Lager, Pia Forsberg, Per-Eric Lindgren, Anna J. Henningsson, and Peter WilhelmssonComments to Author 
Author affiliation: Linköping University, Linköping, Sweden (E. Hero, P. Forsberg, P.-E. Lindgren, A.J. Henningsson, P. Wilhelmsson); Region Jönköping County, Jönköping, Sweden (M. Lager, P.-E. Lindgren, A.J. Henningsson, P. Wilhelmsson)

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Table 1

The prevalence of Neoehrlichia mikurensis determined in 1,644 Ixodes ricinus ticks collected from 1,425 humans who were bitten in Sweden or on the Åland Islands, Finland, during May 2008–November 2009

Developmental stage of the tick Total no. ticks analyzed No. (%) N. mikurensis PCR-positive ticks*
Adult females 392 5 (1.3)
Adult males 7 0
Nymphs 1138 13 (1.1)
Larvae 69 0
Undetermined† 38 0
Total 1644 18 (1.1)

*PCR-positive tick was defined as a tick that tested positive for N. mikurensis in both the SYBR Green and TaqMan real-time PCR assays.
†Tick developmental stage remains undetermined because of damages as previously described (7).

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