Candidatus Neoehrlichia mikurensis – distribution and evaluation of potential risk exposure for human health
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Instytut Medycyny Wsi im. Witolda Chodźki w Lublinie, Polska
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Anna Sawczyn-Domańska   

Instytut Medycyny Wsi im. Witolda Chodźki w Lublinie, Jaczewskiego 2, 20-090, Lublin, Polska
Med Og Nauk Zdr. 2019;25(2):63-69
Introduction and Objective:
Tick-borne diseases are the most prevalent vector-borne diseases concerning human health. During the last two decades the incidences of human tick-borne diseases have increased rapidly. Moreover, newly-recognisedtick-borne pathogens have been described throughout Europe, incl. Candidatus Neoehrlichia mikurensis. The objectiveof the study was an attempt to evaluate the potential risk of human exposure to the new tick-borne pathogen CandidatusNeoehrlichia mikurensis in Poland, based on a literature analysis.

Brief description of the state of knowledge:
Candidatus Neoehrlichia mikurensis is a tick-borne intracellular pathogen belonging to the family Anaplasmataceae. Ixodes ricinus, the most common vector for zoonotic pathogens in Europe and suspected of transmitting Candidatus Neoehrlichia mikurensis to humans. Small mammals, especially rodents, are considered to be the reservoir. The first human infection with Candidatus Neoehrlichia mikurensis was reported in 2010. Since then, neoerlichiosis has been detected mainly in immunocompromised patients in Switzerland, Germany and the Czech Republic.

Summing up:
Candidatus Neoehrlichia mikurensis was detected in questing Ixodes ricinus ticks in Poland, there is therefore the probability of infection among patients bitten by ticks. Available data shows that exposure of people to ticks infected with Candidatus Neoehrlichia mikurensis is relatively low. For this reason, further research to investigate the prevalence of Candidatus Neoehrlichia mikurensis in ticks is necessary. Moreover, knowledge about neoehrlichiosis, even among health professionals, is still limited. Thus, it is vital to implement information and promotional measures to raise the awareness of people about this and other tick-borne diseases.

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