Real Time Micro-Organisms PCR in 82 Horseflies in France

Author(s): François Fournier, Frédéric Durand, Eric Estramon, Yannick Lequette, Christian Perronne, Michel Franck, Alexis Lacout

Introduction: A large number of bacteria other than Borrelia, parasites and viruses are transmitted by tick bites and may be responsible of the persistent polymorphic syndrome possibly due to a tick bite (Syndrome persistant polymorphe après une possible piqûre de tique, SPPT) or the post-treatment Lyme disease syndrome (PTLDS).

Methods: The following micro-organisms were searched for in horseflies, by using real time quantitative polymerase chain reaction (qPCR) : Borrelia burgdorferi sensu lato (sl), Borrelia miyamotoi, Borrelia hermsii, Bartonella spp., Rickettsia spp., Ehrlichia spp., Anaplasma spp., Babesia spp., Theileria spp., Brucella spp., Francisella tularensis, Coxiella burnetii, Chlamydia spp., Mycoplasma spp., Candidatus Neoehrlichia mikurensis, Leishmania spp., Toxoplasma gondii, herperviruses (VZV, EBV, CMV, HHV-6), tick-borne encephalitis virus (TBEV), Bourbon virus, West Nile virus, Chikungunya virus, Dengue virus (1-4), Zika virus, Powassan virus, Eyach virus.

Results: Eighty-two horseflies were analyzed. Thirty-three (40.2 %) horseflies were positive for at least one micro-organism. Among bacteria, Borrelia spp. have not been detected in this study. Mycoplasma spp., Anaplasma spp. and Rickettsia spp. were the most frequent bacteria detected 25 times, 6 times, and twice respectively. Coxiella burnetii, Ehrlichia spp., Francisella tularensis, and Candidatus Neoehrlichia mikurensis were detected once respectively. Among parasites, one Theileria spp. have been detected twice. Among viruses, Bourbon virus and West Nile virus have been detected twice and once respectively.

Conclusion: Our prospective real time qPCR study has shown that horseflies may harbour several micro-organisms which could be pathogenic for animals and humans.