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Agusto FB, Djidjou-Demasse R, Seydi O. Mathematical model of Ehrlichia chaffeensis transmission dynamics in dogs. JOURNAL OF BIOLOGICAL DYNAMICS 2023; 17:2287082. [PMID: 38078365 DOI: 10.1080/17513758.2023.2287082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Accepted: 11/17/2023] [Indexed: 12/18/2023]
Abstract
Ehrlichia chaffeensis is a tick-borne disease transmitted by ticks to dogs. Few studies have mathematical modelled such tick-borne disease in dogs, and none have developed models that incorporate different ticks' developmental stages (discrete variable) as well as the duration of infection (continuous variable). In this study, we develop and analyze a model that considers these two structural variables using integrated semigroups theory. We address the well-posedness of the model and investigate the existence of steady states. The model exhibits a disease-free equilibrium and an endemic equilibrium. We calculate the reproduction number (T 0 ). We establish a necessary and sufficient condition for the bifurcation of an endemic equilibrium. Specifically, we demonstrate that a bifurcation, either backward or forward, can occur at T 0 = 1 , leading to the existence, or not, of an endemic equilibrium even when T 0 < 1 . Finally, numerical simulations are employed to illustrate these theoretical findings.
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Affiliation(s)
- Folashade B Agusto
- Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, KS, USA
| | - Ramsès Djidjou-Demasse
- MIVEGEC, University of Montpellier, CNRS, IRD, Montpellier, France
- Ecole Polytechnique de Thiès, Thiès, Senegal
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Wichianchot S, Hongsrichan N, Maneeruttanarungroj C, Pinlaor S, Iamrod K, Purisarn A, Donthaisong P, Karanis P, Nimsuphan B, Rucksaken R. A newly developed droplet digital PCR for Ehrlichia canis detection: comparisons to conventional PCR and blood smear techniques. J Vet Med Sci 2022; 84:831-840. [PMID: 35473801 PMCID: PMC9246678 DOI: 10.1292/jvms.22-0086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Canine monocytic ehrlichiosis caused by Ehrlichia canis infection is a life-threatening vector-borne disease in dogs worldwide. Routine blood smear has very low sensitivity and cannot accurately provide a quantitative result. Conventional PCR (cPCR) and real-time PCR (qPCR) are widely used as molecular methods for E. canis detection. qPCR is quantitative but relies on standard curves of known samples. To overcome this difficulty, this study developed a new E. canis quantitative detection method, using droplet digital polymerase chain reaction (ddPCR). ddPCR was evaluated against cPCR and blood smears. PCR amplicons and genomic DNA (gDNA) from 12 microscopic positive samples were used to identify the limits of detection (LODs) in ddPCR and cPCR. Our ddPCR was assessed in 92 field samples, it was compared with cPCR and blood smears. ddPCR showed LOD = 1.6 copies/reaction, or 78 times more sensitive than cPCR (LOD = 126 copies/reaction), using PCR amplicons as a template, whereas both ddPCR and cPCR had equal LODs at 0.02 ng gDNA/reaction. In addition, ddPCR had 100% sensitivity and 75% specificity for E. canis detection compared to cPCR and no cross-reaction with other blood pathogens was observed. ddPCR identified more positive samples than cPCR and blood smear. ddPCR improved the overall performance of E. canis detection, with a better LOD and comparable sensitivity and specificity to cPCR. The technique might be helpful for diagnosis of E. canis in light infection, evaluating the number of E. canis and follow-up after treatment.
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Affiliation(s)
- Sakulchit Wichianchot
- Department of Veterinary Technology, Faculty of Veterinary Technology, Kasetsart University
| | | | - Cherdsak Maneeruttanarungroj
- Department of Biology, School of Science, King Mongkut's Institute of Technology Ladkrabang.,Bioenergy Research Unit, School of Science, King Mongkut's Institute of Technology Ladkrabang
| | - Somchai Pinlaor
- Department of Parasitology, Faculty of Medicine, Khon Kaen University
| | - Kantapong Iamrod
- Department of Parasitology, Faculty of Medicine, Khon Kaen University
| | - Andaman Purisarn
- Department of Veterinary Technology, Faculty of Veterinary Technology, Kasetsart University
| | - Peerawich Donthaisong
- Department of Veterinary Technology, Faculty of Veterinary Technology, Kasetsart University
| | - Panagiotis Karanis
- University of Cologne, Medical Faculty and University Hospital Cologne.,University of Nicosia Medical School, Department of Basic and Clinical Sciences
| | - Burin Nimsuphan
- Department of Parasitology, Faculty of Veterinary Medicine, Kasetsart University
| | - Rucksak Rucksaken
- Department of Veterinary Technology, Faculty of Veterinary Technology, Kasetsart University
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Beasley EA, Pessôa-Pereira D, Scorza BM, Petersen CA. Epidemiologic, Clinical and Immunological Consequences of Co-Infections during Canine Leishmaniosis. Animals (Basel) 2021; 11:ani11113206. [PMID: 34827938 PMCID: PMC8614518 DOI: 10.3390/ani11113206] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 11/03/2021] [Accepted: 11/04/2021] [Indexed: 11/24/2022] Open
Abstract
Simple Summary Canine leishmaniosis (CanL), the most severe, visceralizing form of disease caused by Leishmania infantum transmitted by phlebotomine sand flies. CanL is frequently diagnosed in the Mediterranean basin and South America, although it is also found in other regions, including the United States (U.S.). Dogs in these regions are at risk for co-infections, prominently tick-borne diseases. Our review examines epidemiologic, clinical, and immunologic mechanisms found during the most common eight CanL co-infections reported in published literature. Co-infections alter immunologic processes and disease progression impacting CanL diagnosis, therapeutic responses, and prognosis. Abstract Canine leishmaniosis (CanL) is a vector-borne, parasitic disease. CanL is endemic in the Mediterranean basin and South America but also found in Northern Africa, Asia, and the U.S. Regions with both competent sand fly vectors and L. infantum parasites are also endemic for additional infectious diseases that could cause co-infections in dogs. Growing evidence indicates that co-infections can impact immunologic responses and thus the clinical course of both CanL and the comorbid disease(s). The aim for this review is to summarize epidemiologic, clinical, and immunologic factors contributing to eight primary co-infections reported with CanL: Ehrlichia spp., Anaplasma spp., Borrelia spp., Babesia spp., Trypanosoma cruzi, Toxoplasma gondii, Dirofilaria immitis, Paracoccidioides braziliensis. Co-infection causes mechanistic differences in immunity which can alter diagnostics, therapeutic management, and prognosis of dogs with CanL. More research is needed to further explore immunomodulation during CanL co-infection(s) and their clinical impact.
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Affiliation(s)
- Erin A. Beasley
- Department of Epidemiology, College of Public Health, University of Iowa, Iowa City, IA 52242, USA; (E.A.B.); (D.P.-P.); (B.M.S.)
- Center for Emerging Infectious Diseases, University of Iowa, Iowa City, IA 52242, USA
| | - Danielle Pessôa-Pereira
- Department of Epidemiology, College of Public Health, University of Iowa, Iowa City, IA 52242, USA; (E.A.B.); (D.P.-P.); (B.M.S.)
- Center for Emerging Infectious Diseases, University of Iowa, Iowa City, IA 52242, USA
| | - Breanna M. Scorza
- Department of Epidemiology, College of Public Health, University of Iowa, Iowa City, IA 52242, USA; (E.A.B.); (D.P.-P.); (B.M.S.)
- Center for Emerging Infectious Diseases, University of Iowa, Iowa City, IA 52242, USA
| | - Christine A. Petersen
- Department of Epidemiology, College of Public Health, University of Iowa, Iowa City, IA 52242, USA; (E.A.B.); (D.P.-P.); (B.M.S.)
- Center for Emerging Infectious Diseases, University of Iowa, Iowa City, IA 52242, USA
- Correspondence:
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Seroprevalences of Rickettsia conorii, Ehrlichia canis and Coxiella burnetii in Dogs from Montenegro. Acta Parasitol 2019; 64:769-778. [PMID: 31286358 DOI: 10.2478/s11686-019-00098-w] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Accepted: 06/22/2019] [Indexed: 12/24/2022]
Abstract
PURPOSE The incidence of vector-borne zoonoses has been increasing in Europe as a result of global climate change, and rickettsioses are a significant etiologic entity among these infections. The objective of this study was to investigate the seroprevalences of Rickettsia conorii, Ehrlichia canis and Coxiella burnetii in dogs in Montenegro. METHODS The seroepidemiological study covered 259 dogs, of which 155 were owned dogs suspected of infection with agents of rickettsial aetiology from the continental (Podgorica) or five coastal municipalities of Montenegro (Budva, Herceg Novi, Kotor, Ulcinj and Bar), and 104 dogs were from a public shelter in Podgorica. The presence of specific IgG antibodies against R. conorii was analysed using a commercial indirect enzyme-linked immunosorbent assay (ELISA) test, and the presence of antibodies against E. canis and C. burnetii was analysed using commercial indirect immunofluorescence tests (IFAT). RESULTS Seroprevalences of 73.36, 19.3 and 1.16% were determined for R. conorii, E. canis and C. burnetii, respectively. R. conorii was significantly more prevalent (χ2 = 14.53; p < 0.001) in owned dogs (81.93%) than in dogs from the public shelter (60.6%), while E. canis was more prevalent (χ2 = 12.31; p < 0.001) in dogs from the public shelter (29.81%) than in owned dogs (12.26%). Coinfection with two pathogens was determined in 40 (15.44%) dogs, and the prevalence of R. conorii/E. canis (χ2 = 4.23; p < 0.05) was greater in dogs from the public shelter (20.19%) than in owned dogs (10.97%). CONCLUSION The prevailing evidence from this study shows that dogs from Montenegro are exposed to pathogens of veterinary and public health importance. This calls for the One Health approach to sensitise the public on the risks of zoonoses from dogs and to formulate policies and strategies to mitigate their spread and safeguard public health.
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Rucksaken R, Maneeruttanarungroj C, Maswanna T, Sussadee M, Kanbutra P. Comparison of conventional polymerase chain reaction and routine blood smear for the detection of Babesia canis, Hepatozoon canis, Ehrlichia canis, and Anaplasma platys in Buriram Province, Thailand. Vet World 2019; 12:700-705. [PMID: 31327907 PMCID: PMC6584857 DOI: 10.14202/vetworld.2019.700-705] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Accepted: 04/02/2019] [Indexed: 12/01/2022] Open
Abstract
Background and Aim: Dog blood parasites are important tick-borne diseases causing morbidity and mortality in dogs worldwide. Four dog blood parasites species are commonly found in Thailand: Babesia canis, Hepatozoon canis, Ehrlichia canis, and Anaplasma platys. They are transmitted easily by tick species. However, there is little prevalence data available in Thailand. Diseases presentation of blood parasites infection is similar, but the treatment of each species is different. Current diagnosis mainly relies on microscopic examination of a stained blood smear, which has low sensitivity. Therefore, accurate diagnosis is important. This study aims to evaluate the efficacy of the conventional polymerase chain reaction (PCR) method and routine blood smears in the detection of four blood parasites species in dogs from Buriram Province, Thailand. Materials and Methods: In total, 49 EDTA-blood samples were collected from dogs in Buriram Province, Thailand. Blood parasite infection was compared using the Giemsa-stained blood smear technique to identify the parasite under a 100× oil immersion with PCR amplification of the 18S rDNA gene of B. canis and H. canis and the 16S rDNA gene of E. canis and A. platys. Results: Only one dog out of 49 was positive for H. canis based on microscopic examination whereas the PCR results showed that 2.04% (1/49), 4.08% (2/49), 36.73% (18/49), and 30.61% (15/49) of dogs were positive for B. canis, H. canis, E. canis, and A. platys, respectively. Moreover, coinfection was found in 16.33% (8/49) of dogs. Conclusion: This study is the first report to demonstrate the molecular prevalence of blood parasites in domestic dogs in Buriram Province. The results indicated that the PCR method exhibited much higher sensitivity and reliability for blood parasites diagnosis in dogs. Therefore, our data support serious concern regarding the diagnostic technique used in routine blood testing and also provide prevalence data for the management and control of blood parasites in this area.
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Affiliation(s)
- Rucksak Rucksaken
- Department of Veterinary Technology, Faculty of Veterinary Technology, Kasetsart University, Bangkok, Thailand
| | - Cherdsak Maneeruttanarungroj
- Department of Biology, Faculty of Science, King Mongkut's Institute of Technology Ladkrabang, Bangkok, Thailand.,Bioenergy Research Unit, Faculty of Science, King Mongkut's Institute of Technology Ladkrabang, Bangkok, Thailand
| | - Thanaporn Maswanna
- Scientific Instrument Center, Faculty of Science, King Mongkut's Institute of Technology Ladkrabang, Bangkok, Thailand
| | - Metita Sussadee
- Department of Veterinary Technology, Faculty of Veterinary Technology, Kasetsart University, Bangkok, Thailand
| | - Pithai Kanbutra
- Veterinary Teaching Hospital, Faculty of Veterinary Medicine, Khon Kaen University, Khon Kaen, Thailand
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Liu J, Drexel J, Andrews B, Eberts M, Breitschwerdt E, Chandrashekar R. Comparative Evaluation of 2 In-Clinic Assays for Vector-Borne Disease Testing in Dogs. Top Companion Anim Med 2018; 33:114-118. [DOI: 10.1053/j.tcam.2018.09.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 08/14/2018] [Accepted: 09/06/2018] [Indexed: 11/11/2022]
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Baxarias M, Álvarez-Fernández A, Martínez-Orellana P, Montserrat-Sangrà S, Ordeix L, Rojas A, Nachum-Biala Y, Baneth G, Solano-Gallego L. Does co-infection with vector-borne pathogens play a role in clinical canine leishmaniosis? Parasit Vectors 2018; 11:135. [PMID: 29554918 PMCID: PMC5859550 DOI: 10.1186/s13071-018-2724-9] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Accepted: 02/16/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The severity of canine leishmaniosis (CanL) due to Leishmania infantum might be affected by other vector-borne organisms that mimic its clinical signs and clinicopathological abnormalities. The aim of this study was to determine co-infections with other vector-borne pathogens based on serological and molecular techniques in dogs with clinical leishmaniosis living in Spain and to associate them with clinical signs and clinicopathological abnormalities as well as disease severity. METHODS Sixty-one dogs with clinical leishmaniosis and 16 apparently healthy dogs were tested for Rickettsia conorii, Ehrlichia canis, Anaplasma phagocytophilum and Bartonella henselae antigens by the immunofluorescence antibody test (IFAT) and for E. canis, Anaplasma spp., Hepatozoon spp., Babesia spp. and filarioid DNA by polymerase chain reaction (PCR). RESULTS Among the dogs examined by IFAT, the seroprevalences were: 69% for R. conorii, 57% for E. canis, 44% for A. phagocytophilum and 37% for B. henselae; while the prevalences found by PCR were: 8% for Ehrlichia/Anaplasma, 3% for Anaplasma platys and 1% for H. canis. No other pathogen DNA was detected. Statistical association was found between dogs with clinical leishmaniosis and seroreactivity to R. conorii antigen (Fisher's exact test: P = 0.025, OR = 4.1, 95% CI = 1-17) and A. phagocytophilum antigen (Fisher's exact test: P = 0.002, OR = 14.3, 95% CI = 2-626) and being positive to more than one serological or molecular tests (co-infections) (Mann-Whitney test: U = 243, Z = -2.6, n 1 = 14, n 2 = 61, P = 0.01) when compared with healthy dogs. Interestingly, a statistical association was found between the presence of R. conorii, E. canis, A. phagocytophilum and B. henselae antibodies in sick dogs and some clinicopathological abnormalities such as albumin and albumin/globulin ratio decrease and increase in serum globulins. Furthermore, seroreactivity with A. phagocytophilum antigens was statistically associated with CanL clinical stages III and IV. CONCLUSIONS This study demonstrates that dogs with clinical leishmaniosis from Catalonia (Spain) have a higher rate of co-infections with other vector-borne pathogens when compared with healthy controls. Furthermore, positivity to some vector-borne pathogens was associated with more marked clinicopathological abnormalities as well as disease severity with CanL.
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Affiliation(s)
- Marta Baxarias
- Departament de Medicina i Cirurgia Animals, Facultat de Veterinària, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Alejandra Álvarez-Fernández
- Departament de Medicina i Cirurgia Animals, Facultat de Veterinària, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Pamela Martínez-Orellana
- Departament de Medicina i Cirurgia Animals, Facultat de Veterinària, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Sara Montserrat-Sangrà
- Departament de Medicina i Cirurgia Animals, Facultat de Veterinària, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Laura Ordeix
- Departament de Medicina i Cirurgia Animals, Facultat de Veterinària, Universitat Autònoma de Barcelona, Bellaterra, Spain.,Hospital Clínic Veterinari, Facultat de Veterinària, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Alicia Rojas
- Koret School of Veterinary Medicine, Hebrew University, Rehovot, Israel
| | | | - Gad Baneth
- Koret School of Veterinary Medicine, Hebrew University, Rehovot, Israel
| | - Laia Solano-Gallego
- Departament de Medicina i Cirurgia Animals, Facultat de Veterinària, Universitat Autònoma de Barcelona, Bellaterra, Spain.
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Dahmani M, Loudahi A, Mediannikov O, Fenollar F, Raoult D, Davoust B. Molecular detection of Anaplasma platys and Ehrlichia canis in dogs from Kabylie, Algeria. Ticks Tick Borne Dis 2015; 6:198-203. [PMID: 25583345 DOI: 10.1016/j.ttbdis.2014.12.007] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Revised: 12/18/2014] [Accepted: 12/27/2014] [Indexed: 10/24/2022]
Abstract
Ehrlichia canis and Anaplasma platys are bacteria belonging to the Anaplasmataceae family that cause acute, self-limiting and sometimes fatal vector-borne infections in dogs. These bacteria have been reported worldwide and are transmitted mainly by Rhipicephalus sanguineus. Aside from a report on E. canis once in 1935, no other Anaplasmataceae bacteria have been reported in Algeria to date. The aim of this study was to identify the microbial species implicated in ehrlichiosis and anaplasmosis by a molecular epidemiological survey in dogs. The study was carried out in Kabylie, in northeast Algeria. Sampling was performed in 11 municipalities in the province of Tizi Ouzou and 2 municipalities in the province of Béjaïa. Peripheral blood samples from 110 dogs were screened by qPCR, which is capable of identifying most Anaplasmataceae bacteria. Out of 110, a total of 13 samples screened positive (7/110 E. canis and 6/110 A. platys), and two genetic variants of A. platys and one of E. canis were identified. This is the first study to report the presence of A. platys in dogs from Algeria using a molecular investigative method. This survey was conducted in early spring. As tick activity can affect the prevalence of these pathogens in dogs, further investigations are needed to establish the year-round prevalence of these infections.
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Affiliation(s)
- Mustapha Dahmani
- Research Unit of Emerging Infectious and Tropical Diseases (URMITE) UMR CNRS, 7278 IRD 198 INSERM 1095, Aix-Marseille University, Marseille, France
| | - Abdelghani Loudahi
- Research Unit of Emerging Infectious and Tropical Diseases (URMITE) UMR CNRS, 7278 IRD 198 INSERM 1095, Aix-Marseille University, Marseille, France
| | - Oleg Mediannikov
- Research Unit of Emerging Infectious and Tropical Diseases (URMITE) UMR CNRS, 7278 IRD 198 INSERM 1095, Aix-Marseille University, Marseille, France; Research Unit of Emerging Infectious and Tropical Diseases (URMITE) UMR CNRS, 7278 IRD 198 INSERM 1095, Institute of Research for the Development, Dakar, Senegal
| | - Florence Fenollar
- Research Unit of Emerging Infectious and Tropical Diseases (URMITE) UMR CNRS, 7278 IRD 198 INSERM 1095, Aix-Marseille University, Marseille, France; Research Unit of Emerging Infectious and Tropical Diseases (URMITE) UMR CNRS, 7278 IRD 198 INSERM 1095, Institute of Research for the Development, Dakar, Senegal
| | - Didier Raoult
- Research Unit of Emerging Infectious and Tropical Diseases (URMITE) UMR CNRS, 7278 IRD 198 INSERM 1095, Aix-Marseille University, Marseille, France; Research Unit of Emerging Infectious and Tropical Diseases (URMITE) UMR CNRS, 7278 IRD 198 INSERM 1095, Institute of Research for the Development, Dakar, Senegal
| | - Bernard Davoust
- Research Unit of Emerging Infectious and Tropical Diseases (URMITE) UMR CNRS, 7278 IRD 198 INSERM 1095, Aix-Marseille University, Marseille, France.
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Stillman BA, Monn M, Liu J, Thatcher B, Foster P, Andrews B, Little S, Eberts M, Breitschwerdt EB, Beall MJ, Chandrashekar R. Performance of a commercially available in-clinic ELISA for detection of antibodies againstAnaplasma phagocytophilum, Anaplasma platys, Borrelia burgdorferi, Ehrlichia canis, andEhrlichia ewingiiandDirofilaria immitisantigen in dogs. J Am Vet Med Assoc 2014; 245:80-6. [DOI: 10.2460/javma.245.1.80] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Tappe J, Strube C. Anaplasma phagocytophilum and Rickettsia spp. infections in hard ticks (Ixodes ricinus) in the city of Hanover (Germany): revisited. Ticks Tick Borne Dis 2013; 4:432-8. [PMID: 23838023 DOI: 10.1016/j.ttbdis.2013.04.009] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2013] [Revised: 04/19/2013] [Accepted: 04/24/2013] [Indexed: 10/26/2022]
Abstract
The present study aimed to determine the prevalence of Rickettsiales (A. phagocytophilum and Rickettsia spp.) in 2100 I. ricinus ticks collected at 10 different sampling sites every month during the tick season 2010 in the city of Hanover, northern Germany. At the same time, the results served as a fifth-year-follow-up study to monitor whether changes or stagnation of tick infection rates - possibly due to climate change--were obvious or not. To detect infections with A. phagocytophilum and/or Rickettsia spp., tick samples were analysed by quantitative real-time PCR. Differentiation of Rickettsia species was accomplished using real-time pyrosequencing technology. Overall, 4.5% (94/2100) of the collected ticks were tested positive for A. phagocytophilum and 26.2% (551/2100) were positive for Rickettsia spp. infections. Species differentiation of Rickettsia-positive ticks via real-time pyrosequencing was possible in 48.6% (268/551) of samples, which were all identified as R. helvetica. Coinfections with both pathogens were found in 1.0% (20/2100) of ticks. Statistically significant seasonal fluctuations between sampling months as well as local differences between sampling sites were detected for Rickettsia spp. infection rates. For A. phagocytophilum infections, only significant seasonal variations were found. When comparing infection rates of Hanoverian ticks in 2010 to those in 2005, infection rates of A. phagocytophilum-infected nymphs increased statistically significant (P=0.008, power: 0.762) from 2.3% in 2005 (Schicht et al., 2011) to 4.5% in 2010. Rickettsia spp. infections in female ticks decreased significantly (P=0.049, power: 0.491) from 41.8% in 2005 (Schicht et al., 2012) to 32.4% in 2010. Comparison of the remaining tick stages showed no statistically significant differences.
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Affiliation(s)
- Julia Tappe
- Institute for Parasitology, University of Veterinary Medicine Hannover, Buenteweg 17, 30559 Hanover, Germany
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