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Jahfari S.,National Institute for Public Health and Environment RIVM | Fonville M.,National Institute for Public Health and Environment RIVM | Hengeveld P.,National Institute for Public Health and Environment RIVM | Reusken C.,National Institute for Public Health and Environment RIVM | And 7 more authors.
Parasites and Vectors

Background: Neoehrlichia mikurensis s an emerging and vector-borne zoonosis: The first human disease cases were reported in 2010. Limited information is available about the prevalence and distribution of Neoehrlichia mikurensis in Europe, its natural life cycle and reservoir hosts. An Ehrlichia-like schotti variant has been described in questing Ixodes ricinus ticks, which could be identical to Neoehrlichia mikurensis. Methods: Three genetic markers, 16S rDNA, gltA and GroEL, of Ehrlichia schotti-positive tick lysates were amplified, sequenced and compared to sequences from Neoehrlichia mikurensis. Based on these DNA sequences, a multiplex real-time PCR was developed to specifically detect Neoehrlichia mikurensis in combination with Anaplasma phagocytophilum in tick lysates. Various tick species from different life-stages, particularly Ixodes ricinus nymphs, were collected from the vegetation or wildlife. Tick lysates and DNA derived from organs of wild rodents were tested by PCR-based methods for the presence of Neoehrlichia mikurensis. Prevalence of Neoehrlichia mikurensis was calculated together with confidence intervals using Fisher's exact test. Results: The three genetic markers of Ehrlichia schotti-positive field isolates were similar or identical to Neoehrlichia mikurensis. Neoehrlichia mikurensis was found to be ubiquitously spread in the Netherlands and Belgium, but was not detected in the 401 tick samples from the UK. Neoehrlichia mikurensis was found in nymphs and adult Ixodes ricinus ticks, but neither in their larvae, nor in any other tick species tested. Neoehrlichia mikurensis was detected in diverse organs of some rodent species. Engorging ticks from red deer, European mouflon, wild boar and sheep were found positive for Neoehrlichia mikurensis. Conclusions: Ehrlichia schotti is similar, if not identical, to Neoehrlichia mikurensis. Neoehrlichia mikurensis is present in questing Ixodes ricinus ticks throughout the Netherlands and Belgium. We propose that Ixodes ricinus can transstadially, but not transovarially, transmit this microorganism, and that different rodent species may act as reservoir hosts. These data further imply that wildlife and humans are frequently exposed to Neoehrlichia mikurensis-infected ticks through tick bites. Future studies should aim to investigate to what extent Neoehrlichia mikurensis poses a risk to public health. © 2012 Jahfari et al.; licensee BioMed Central Ltd. Source

Jahfari S.,National Institute for Public Health and Environment RIVM | Coipan E.C.,National Institute for Public Health and Environment RIVM | Coipan E.C.,Wageningen University | Fonville M.,National Institute for Public Health and Environment RIVM | And 17 more authors.
Parasites and Vectors

Background: Anaplasma phagocytophilum is the etiological agent of granulocytic anaplasmosis in humans and animals. Wild animals and ticks play key roles in the enzootic cycles of the pathogen. Potential ecotypes of A. phagocytophilum have been characterized genetically, but their host range, zoonotic potential and transmission dynamics has only incompletely been resolved. Methods. The presence of A. phagocytophilum DNA was determined in more than 6000 ixodid ticks collected from the vegetation and wildlife, in 289 tissue samples from wild and domestic animals, and 69 keds collected from deer, originating from various geographic locations in The Netherlands and Belgium. From the qPCR-positive lysates, a fragment of the groEL-gene was amplified and sequenced. Additional groEL sequences from ticks and animals from Europe were obtained from GenBank, and sequences from human cases were obtained through literature searches. Statistical analyses were performed to identify A. phagocytophilum ecotypes, to assess their host range and their zoonotic potential. The population dynamics of A. phagocytophilum ecotypes was investigated using population genetic analyses. Results: DNA of A. phagocytophilum was present in all stages of questing and feeding Ixodes ricinus, feeding I. hexagonus, I. frontalis, I. trianguliceps, and deer keds, but was absent in questing I. arboricola and Dermacentor reticulatus. DNA of A. phagocytophilum was present in feeding ticks and tissues from many vertebrates, including roe deer, mouflon, red foxes, wild boar, sheep and hedgehogs but was rarely found in rodents and birds and was absent in badgers and lizards. Four geographically dispersed A. phagocytophilum ecotypes were identified, that had significantly different host ranges. All sequences from human cases belonged to only one of these ecotypes. Based on population genetic parameters, the potentially zoonotic ecotype showed significant expansion. Conclusion: Four ecotypes of A. phagocytophilum with differential enzootic cycles were identified. So far, all human cases clustered in only one of these ecotypes. The zoonotic ecotype has the broadest range of wildlife hosts. The expansion of the zoonotic A. phagocytophilum ecotype indicates a recent increase of the acarological risk of exposure of humans and animals. © 2014 Jahfari et al.; licensee BioMed Central Ltd. Source

Hukic M.,University of Sarajevo | Valjevac A.,University of Sarajevo | Tulumovic D.,University of Tuzla | Numanovic F.,University of Tuzla | Heyman P.,Research Laboratory for Vector Borne Diseases
European Journal of Clinical Microbiology and Infectious Diseases

Dobrava (DOBV) and Puumala (PUUV) viruses are endemic throughout the Balkans and cause haemorrhagic fever with renal syndrome (HFRS). The aim of this study was to assess the impact of two different hantaviruses on renal function in HFRS patients during the acute stage of illness. We also aimed to assess the DOBV and PUUV distribution between symptomatic HFRS patients and asymptomatic hantavirus antibody-positive subjects. The study included 264 symptomatic HFRS patients and 63 asymptomatic hantavirus antibody-positive healthy subjects. In our study, 131 (49.6%) HFRS patients were regarded as PUUV- and 69 (26.1%) as DOBV-infected patients, while in 64 (24.2%) of HFRS patients that showed all clinical and biochemical signs of HFRS, the causal hantavirus could not be determined with commercially available tests. DOBV-infected patients were associated with more requirements for haemodialysis treatment, lower diuresis and higher serum creatinine and urea values compared to PUUV-infected patients. PUUV was significantly predominant in asymptomatic hantavirus antibody-positive subjects (69.8%) compared to HFRS patients. DOBV was present in 17.5% of asymptomatic subjects and, interestingly, the preferential hantavirus serotype could not be determined in 12.7% of the asymptomatic antibody-positive subjects. © 2010 Springer-Verlag. Source

Cochez C.,Research Laboratory for Vector Borne Diseases | Heyman P.,Research Laboratory for Vector Borne Diseases | Heylen D.,University of Antwerp | Fonville M.,National Institute for Public Health and Environment RIVM | And 4 more authors.
Zoonoses and Public Health

Borrelia miyamotoi is a tick-borne bacterium that may cause relapsing fever in humans. As this pathogen has been discovered in Europe only recently, only little is known about its local impact on human health and its spatial distribution. In this study, we show the results of PCR screenings for B. miyamotoi in flagged Ixodes ricinus from Belgium and the Netherlands. B. miyamotoi was detected in nine of thirteen, and three of five locations from the Netherlands and Belgium, respectively. These outcomes indicate that B. miyamotoi is more spread than previously thought. The mean infection rate B. miyamotoi was 1.14% for Belgium and 3.84% for the Netherlands. © 2014 Blackwell Verlag GmbH. Source

Claerebout E.,Ghent University | Losson B.,University of Liege | Cochez C.,Research Laboratory for Vector Borne Diseases | Casaert S.,Ghent University | And 7 more authors.
Parasites and Vectors

Background: Although Ixodes spp. are the most common ticks in North-Western Europe, recent reports indicated an expanding geographical distribution of Dermacentor reticulatus in Western Europe. Recently, the establishment of a D. reticulatus population in Belgium was described. D. reticulatus is an important vector of canine and equine babesiosis and can transmit several Rickettsia species, Coxiella burnetii and tick-borne encephalitis virus (TBEV), whilst Ixodes spp. are vectors of pathogens causing babesiosis, borreliosis, anaplasmosis, rickettsiosis and TBEV. Methods. A survey was conducted in 2008-2009 to investigate the presence of different tick species and associated pathogens on dogs and cats in Belgium. Ticks were collected from dogs and cats in 75 veterinary practices, selected by stratified randomization. All collected ticks were morphologically determined and analysed for the presence of Babesia spp., Borrelia spp., Anaplasma phagocytophilum and Rickettsia DNA. Results: In total 2373 ticks were collected from 647 dogs and 506 cats. Ixodes ricinus (76.4%) and I. hexagonus (22.6%) were the predominant species. Rhipicephalus sanguineus (0.3%) and D. reticulatus (0.8%) were found in low numbers on dogs only. All dogs infested with R. sanguineus had a recent travel history, but D. reticulatus were collected from a dog without a history of travelling abroad. Of the collected Ixodes ticks, 19.5% were positive for A. phagocytophilum and 10.1% for Borrelia spp. (B. afzelii, B. garinii, B. burgdorferi s.s., B. lusitaniae, B. valaisiana and B. spielmanii). Rickettsia helvetica was found in 14.1% of Ixodes ticks. All Dermacentor ticks were negative for all the investigated pathogens, but one R. sanguineus tick was positive for Rickettsia massiliae. Conclusion: D. reticulatus was confirmed to be present as an indigenous parasite in Belgium. B. lusitaniae and R. helvetica were detected in ticks in Belgium for the first time. © 2013 Claerebout et al.; licensee BioMed Central Ltd. Source

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