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Volume 31, Number 11—November 2025

Research

Tickborne Neoehrlichia mikurensis in the Blood of Blood Donors, Norway, 2023

Hanne QuarstenComments to Author , Charlotte N.B. Ryen, Linn K.T. Mørk, Christine Wennerås, and Christine T. Steinsvåg
Author affiliation: Sørlandet Hospital, Kristiansand, Norway (H. Quarsten, C.N.B. Ryen, L.K.T. Mørk, C.T. Steinsvåg); Sahlgrenska Academy at the University of Gothenburg and Sahlgrenska University Hospital, Göteborg, Sweden (C. Wennerås)

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Table 2

Characteristics of blood donors at study inclusion and after treatment with antimicrobial drugs in study of tickborne Neoehrlichia mikurensis in the blood of blood donors, Norway, 2023*

Reported data No. (%) blood donors
p value
N. mikurensis DNA negative N. mikurensis DNA positive
Tick bite in current year 97/454 (21) 16/45 (36) 0.04
History of tick bites 370/454 (82) 40/45 (89) 0.31
History of borreliosis/TBE†
 38/454 (8.4)
 6/45 (13)
 0.27
Health complaints in previous 4 months
Pain 10/451 (2.2) 1/44 (2.3) >0.99
Headache 6/451 (1.3) 2/44 (4.6) 0.15
Dizziness 3/451 (0.7) 0/44 (0) >0.99
Fever 0/451 (0) 0/44 (0) >0.99
Night sweat 8/451 (1.8) 2/44 (4.6) 0.22
Sleep problems 11/450 (2.4) 1/44 (2.3) >0.99
Nausea/digestive problems 0/451 (0) 0/44 (0) >0.99
Fatigue 22/451 (4.9) 3/44 (6.8) 0.48
Rash
 4/450 (0.9)
 0/44 (0)
 >0.99
Improvement of health complaints after treatment with antimicrobial drugs
Pain 3/29 (10)
Headache 4/29 (14)
Dizziness 2/29 (6.9)
Fever 1/29 (3.5)
Night sweat 2/29 (6.9)
Sleep problems 4/29 (14)
Nausea/digestive problems 2/29 (6.9)
Fatigue 3/29 (10)
Rash 1/29 (3.5)

*p values determined by Fisher exact test. TBE, tickborne encephalitis. †History of borreliosis/TBE; 25 were reported as borreliosis, 19 were unspecified (either borrelioses or TBE) and none reported TBE.

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