Borrelia miyamotoi and Candidatus Neoehrlichia mikurensis in Ixodes ricinus Ticks, Romania

To the Editor: Ixodes spp. ticks are vectors for human and animal pathogens. Ix. ricinus ticks are widely distributed, frequently reported to feed on humans, and the main vector for a large variety of tickborne pathogens (1). The effect of ticks and tickborne diseases on public health, animal health and welfare, and animal production appears to be an increasing global problem, which will lead to considerable economic costs (2).

available on the presence of relapsing fever group borreliae in this country.
Candidatus Neoehrlichia mikurensis and Anaplasma phagocytophilum are obligate, intracellular, tickborne pathogens of the family Anaplasmataceae; both are emerging zoonotic agents. Candidatus N. mikurensis causes monocytotropic ehrlichiosis in canids and humans and granulocytic anaplasmosis in humans and domestic animals (8). These 2 pathogens are found throughout Europe in Ix. ricinus ticks (8). A. phagocytophilum has been reported in questing Ix. ricinus ticks, dogs, wild boars, hedgehogs, and tortoises in Romania (9). Recently, Candidatus N. mikurensis was detected in an Ix. ricinus tick that had bitten a human in Romania (10). This recently discovered tickborne agent was shown to be a risk for disease in humans and has been detected in questing Ix. ricinus ticks throughout Europe and in animal tissue samples and human patients (8).
Relapsing fever spirochetes and potential public health risks associated with tickborne pathogens are a serious medical problem. Thus, we assessed the presence of B. miyamotoi, A. phagocytophilum, and Candidatus N. mikurensis in questing Ix. ricinus ticks in Romania.
Questing Ix. ricinus ticks were available from previous studies conducted by our research group. A random sampling approach was used as described (7). To detect potentially pathogenic bacteria, 468 questing Ix. ricinus ticks were collected from 4 regions from Romania, randomly selected, and analyzed.
In Romania, the density of Ix. ricinus ticks is high and their host diversity is extensive (7). However, data for effects of tickborne pathogens on public health are scarce in this country. In this study, we detected B. miyamotoi, A. phagocytophilum, and Candidatus N. mikurensis in questing Ix. ricinus ticks in Romania, which confirms the emerging trend of these pathogens in Europe. Because of the scarcity of information on human infections with these pathogens in Romania, serologic and molecular investigations and their implementation are needed for diagnosis, which might help in assessing the effect of these pathogens on public health.