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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 2

Characteristics of participants with Neoehrlicha mikurensis DNA detected in their plasma in a study of ticks and tick-bitten persons, Sweden and Finland, 2008–2009.

Participant sex Participant age, y Tick developmental stage Tick feeding time, h‡ PCR results§ Self-reported symptoms¶ Sought medical care
Female* 41 Nymph <24 Positive/negative Headache, fatigue, radiating pain, myalgia, numbness Yes
Female† 68 Nymph 43 Negative/positive Fatigue, neck pain, myalgia, numbness No

*Participant was recruited to a primary healthcare center in southernmost Sweden (Appendix Figure, https://wwwnc.cdc.gov/EID/article/31/11/24-1850-App1.pdf).
†Participant was recruited to a primary healthcare center in south-central Sweden (Appendix Figure).
‡Estimation of the duration of blood feeding was calculated as described previously (9).
§Plasma samples collected during initial inclusion and then at follow-up visit.
¶Self-reported symptoms described in the questionnaire that was completed during the follow-up meeting 3 months after the tick bite.

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