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Hojgaard A, Foster E, Maes SE, Osikowicz LM, Parise CM, Villalpando J, Eisen RJ. Geographic variation in the distribution of Anaplasma phagocytophilum variants in host-seeking Ixodes scapularis nymphs and adults in the eastern United States elucidated using next generation sequencing. Ticks Tick Borne Dis 2024; 15:102360. [PMID: 38820870 DOI: 10.1016/j.ttbdis.2024.102360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Revised: 05/05/2024] [Accepted: 05/19/2024] [Indexed: 06/02/2024]
Abstract
Human anaplasmosis cases, caused by Anaplasma phagocytophilum, are increasing in the United States. This trend is explained, in part, by expansion in the geographic range of the primary vector, Ixodes scapularis. Multiple variants of A. phagocytophilum have been identified in field collected ticks, but only a single variant (human active, or "Ap-ha," variant) has been shown to be pathogenic in humans. Until recently, laboratory methods used to differentiate variants were cumbersome and seldomly used in large scale assessments of the pathogen's geographic distribution. As a result, many surveys reported A. phagocytophilum without segregating variants. Lack of discrimination among A. phagocytophilum variants could lead to overestimation of anaplasmosis risk to humans. Next Generation Sequencing (NGS) assays were recently developed to efficiently detect multiple Ixodes scapularis-borne human pathogens including Ap-ha. In this study, we utilized NGS to detect and differentiate A. phagocytophilum variants (Ap-ha vs. non ha) in host-seeking I. scapularis nymphs and adults collected across 23 states in the eastern United States from 2012 to 2023 as part of national tick surveillance efforts and research studies. Many of the included ticks were tested previously using a TaqMan PCR assay that could detect A. phagocytophilum but could not differentiate variants. We retested A. phagocytophilum infected ticks with NGS to differentiate variants. Anaplasma phagocytophilum (any variant) was identified in 165 (35 %) of 471 counties from which ticks were tested, whereas Ap-ha was detected in 70 (15 %) of 469 counties where variants were differentiated. Both variants were identified in 32 % (n = 40) of 126 counties with either variant detected. Among states where A. phagocytophilum (any variant) was detected, prevalence ranged from 2 % to 19 % in unfed adults and from 0.2 % to 7.8 % in unfed nymphs; prevalence of Ap-ha variant ranged from 0.0 % to 16 % in adults, and 0.0 % to 4.6 % in nymphs.
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Affiliation(s)
- Andrias Hojgaard
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, CO, USA.
| | - Erik Foster
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, CO, USA
| | - Sarah E Maes
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, CO, USA
| | - Lynn M Osikowicz
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, CO, USA
| | - Christina M Parise
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, CO, USA
| | - Joel Villalpando
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, CO, USA
| | - Rebecca J Eisen
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, CO, USA
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Khogali R, Bastos A, Bargul JL, Getange D, Kabii J, Masiga D, Villinger J. Tissue-specific localization of tick-borne pathogens in ticks collected from camels in Kenya: insights into vector competence. Front Cell Infect Microbiol 2024; 14:1382228. [PMID: 38698904 PMCID: PMC11063324 DOI: 10.3389/fcimb.2024.1382228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Accepted: 03/15/2024] [Indexed: 05/05/2024] Open
Abstract
Background Tick-borne pathogen (TBP) surveillance studies often use whole-tick homogenates when inferring tick-pathogen associations. However, localized TBP infections within tick tissues (saliva, hemolymph, salivary glands, and midgut) can inform pathogen transmission mechanisms and are key to disentangling pathogen detection from vector competence. Methods We screened 278 camel blood samples and 504 tick tissue samples derived from 126 camel ticks sampled in two Kenyan counties (Laikipia and Marsabit) for Anaplasma, Ehrlichia, Coxiella, Rickettsia, Theileria, and Babesia by PCR-HRM analysis. Results Candidatus Anaplasma camelii infections were common in camels (91%), but absent in all samples from Rhipicephalus pulchellus, Amblyomma gemma, Hyalomma dromedarii, and Hyalomma rufipes ticks. We detected Ehrlichia ruminantium in all tissues of the four tick species, but Rickettsia aeschlimannii was only found in Hy. rufipes (all tissues). Rickettsia africae was highest in Am. gemma (62.5%), mainly in the hemolymph (45%) and less frequently in the midgut (27.5%) and lowest in Rh. pulchellus (29.4%), where midgut and hemolymph detection rates were 17.6% and 11.8%, respectively. Similarly, in Hy. dromedarii, R. africae was mainly detected in the midgut (41.7%) but was absent in the hemolymph. Rickettsia africae was not detected in Hy. rufipes. No Coxiella, Theileria, or Babesia spp. were detected in this study. Conclusions The tissue-specific localization of R. africae, found mainly in the hemolymph of Am. gemma, is congruent with the role of this tick species as its transmission vector. Thus, occurrence of TBPs in the hemolymph could serve as a predictor of vector competence of TBP transmission, especially in comparison to detection rates in the midgut, from which they must cross tissue barriers to effectively replicate and disseminate across tick tissues. Further studies should focus on exploring the distribution of TBPs within tick tissues to enhance knowledge of TBP epidemiology and to distinguish competent vectors from dead-end hosts.
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Affiliation(s)
- Rua Khogali
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
- Department of Zoology and Entomology, University of Pretoria, Pretoria, South Africa
- Department of Parasitology, Faculty of Veterinary Medicine, University of Khartoum, Khartoum North, Sudan
| | - Armanda Bastos
- Department of Zoology and Entomology, University of Pretoria, Pretoria, South Africa
- Department of Veterinary Tropical Diseases, University of Pretoria, Pretoria, South Africa
| | - Joel L. Bargul
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
- Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology (JKUAT), Nairobi, Kenya
| | - Dennis Getange
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
- School of Life Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - James Kabii
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | - Daniel Masiga
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | - Jandouwe Villinger
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
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Mwaki DM, Kidambasi KO, Kinyua J, Ogila K, Kigen C, Getange D, Villinger J, Masiga DK, Carrington M, Bargul JL. Molecular detection of novel Anaplasma sp . and zoonotic hemopathogens in livestock and their hematophagous biting keds (genus Hippobosca) from Laisamis, northern Kenya. OPEN RESEARCH AFRICA 2022; 5:23. [PMID: 37396343 PMCID: PMC10314185 DOI: 10.12688/openresafrica.13404.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Accepted: 05/13/2022] [Indexed: 07/04/2023]
Abstract
Background: Livestock are key sources of livelihood among pastoral communities. Livestock productivity is chiefly constrained by pests and diseases. Due to inadequate disease surveillance in northern Kenya, little is known about pathogens circulating within livestock and the role of livestock-associated biting keds (genus Hippobosca) in disease transmission. We aimed to identify the prevalence of selected hemopathogens in livestock and their associated blood-feeding keds. Methods: We randomly collected 389 blood samples from goats (245), sheep (108), and donkeys (36), as well as 235 keds from both goats and sheep (116), donkeys (11), and dogs (108) in Laisamis, Marsabit County, northern Kenya. We screened all samples for selected hemopathogens by high-resolution melting (HRM) analysis and sequencing of PCR products amplified using primers specific to the genera: Anaplasma, Trypanosoma, Clostridium, Ehrlichia, Brucella, Theileria, and Babesia. Results: In goats, we detected Anaplasma ovis (84.5%), a novel Anaplasma sp. (11.8%), Trypanosoma vivax (7.3%), Ehrlichia canis (66.1%), and Theileria ovis (0.8%). We also detected A. ovis (93.5%), E. canis (22.2%), and T. ovis (38.9%) in sheep. In donkeys, we detected ' Candidatus Anaplasma camelii' (11.1%), T. vivax (22.2%), E. canis (25%), and Theileria equi (13.9%). In addition, keds carried the following pathogens; goat/sheep keds - T. vivax (29.3%) , Trypanosoma evansi (0.86%), Trypanosoma godfreyi (0.86%), and E. canis (51.7%); donkey keds - T. vivax (18.2%) and E. canis (63.6%); and dog keds - T. vivax (15.7%), T. evansi (0.9%), Trypanosoma simiae (0.9%) , E. canis (76%), Clostridium perfringens (46.3%), Bartonella schoenbuchensis (76%), and Brucella abortus (5.6%). Conclusions: We found that livestock and their associated ectoparasitic biting keds carry a number of infectious hemopathogens, including the zoonotic B. abortus. Dog keds harbored the most pathogens, suggesting dogs, which closely interact with livestock and humans, as key reservoirs of diseases in Laisamis. These findings can guide policy makers in disease control.
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Affiliation(s)
- Daniel M. Mwaki
- Animal Health Department/Molecular Biology and Bioinformatics Unit, International Centre of Insect Physiology and Ecology (icipe), Nairobi, P.O. BOX 30772-00100, Kenya
- Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology (JKUAT), Nairobi, P.O. BOX 62000-00200, Kenya
- Department of Zoology, Jomo Kenyatta University of Agriculture and Technology (JKUAT), Nairobi, P.O. Box 62000-00200, Kenya
| | - Kevin O. Kidambasi
- Animal Health Department/Molecular Biology and Bioinformatics Unit, International Centre of Insect Physiology and Ecology (icipe), Nairobi, P.O. BOX 30772-00100, Kenya
| | - Johnson Kinyua
- Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology (JKUAT), Nairobi, P.O. BOX 62000-00200, Kenya
| | - Kenneth Ogila
- Department of Zoology, Jomo Kenyatta University of Agriculture and Technology (JKUAT), Nairobi, P.O. Box 62000-00200, Kenya
| | - Collins Kigen
- Animal Health Department/Molecular Biology and Bioinformatics Unit, International Centre of Insect Physiology and Ecology (icipe), Nairobi, P.O. BOX 30772-00100, Kenya
| | - Dennis Getange
- Animal Health Department/Molecular Biology and Bioinformatics Unit, International Centre of Insect Physiology and Ecology (icipe), Nairobi, P.O. BOX 30772-00100, Kenya
- Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology (JKUAT), Nairobi, P.O. BOX 62000-00200, Kenya
| | - Jandouwe Villinger
- Animal Health Department/Molecular Biology and Bioinformatics Unit, International Centre of Insect Physiology and Ecology (icipe), Nairobi, P.O. BOX 30772-00100, Kenya
| | - Daniel K. Masiga
- Animal Health Department/Molecular Biology and Bioinformatics Unit, International Centre of Insect Physiology and Ecology (icipe), Nairobi, P.O. BOX 30772-00100, Kenya
| | - Mark Carrington
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK
| | - Joel L. Bargul
- Animal Health Department/Molecular Biology and Bioinformatics Unit, International Centre of Insect Physiology and Ecology (icipe), Nairobi, P.O. BOX 30772-00100, Kenya
- Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology (JKUAT), Nairobi, P.O. BOX 62000-00200, Kenya
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Chiuya T, Villinger J, Masiga DK, Ondifu DO, Murungi MK, Wambua L, Bastos ADS, Fèvre EM, Falzon LC. Molecular prevalence and risk factors associated with tick-borne pathogens in cattle in western Kenya. BMC Vet Res 2021; 17:363. [PMID: 34838023 PMCID: PMC8627057 DOI: 10.1186/s12917-021-03074-7] [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] [Received: 05/25/2021] [Accepted: 11/05/2021] [Indexed: 11/29/2022] Open
Abstract
Background Tick-borne pathogens (TBPs) are of global importance, especially in sub-Saharan Africa where they represent a major constraint to livestock production. Their association with human disease is also increasingly recognized, signalling their zoonotic importance. It is therefore crucial to investigate TBPs prevalence in livestock populations and the factors associated with their presence. We set out to identify TBPs present in cattle and to determine associated risk factors in western Kenya, where smallholder livestock production is important for subsistence and market-driven income. Results Tick-borne pathogen infections in blood samples collected from cattle at livestock markets and slaughterhouses between May 2017 and January 2019 were identified by high-resolution melting analysis and sequencing of PCR products of genus-specific primers. Of the 422 cattle sampled, 30.1% (127/422) were infected with at least one TBP, while 8.8% (37/422) had dual infections. Anaplasma spp. (19.7%) were the most prevalent, followed by Theileria (12.3%), Ehrlichia (6.6%), and Babesia (0.2%) spp. Sequence analysis of the TBPs revealed them to be Anaplasma platys-like organisms (13.5%), Theileria velifera (7.4%), Anaplasma marginale (4.9%), Theileria mutans (3.1%), Theileria parva (1.6%), and Babesia bigemina (0.2%). Ehrlichia ruminantium, Rickettsia spp., and arboviruses were not detected. Exotic breeds of cattle were more likely to be infected with A. marginale compared to local breeds (OR: 7.99, 95% CI: 3.04–22.02, p < 0.001). Presence of ticks was a significant predictor for Anaplasma spp. (OR: 2.18, 95% CI: 1.32–3.69, p = 0.003) and Ehrlichia spp. (OR: 2.79, 95% CI: 1.22–7.23, p = 0.022) infection. Cattle sampled at slaughterhouses were more likely to be positive for Anaplasma spp. (OR: 1.64, 95% CI: 1.01–2.70, p = 0.048) and A. marginale (OR: 3.84, 95% CI: 1.43–12.21, p = 0.012), compared to those sampled at livestock markets. Conclusion This study reports TBP prevalence and associated risk factors in western Kenya, factors which are key to informing surveillance and control measures.
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Affiliation(s)
- Tatenda Chiuya
- International Centre of Insect Physiology and Ecology (icipe), P.O Box 30772-00100, Nairobi, Kenya. .,Department of Zoology and Entomology, University of Pretoria, Private Bag 20, Pretoria, 0028, South Africa.
| | - Jandouwe Villinger
- International Centre of Insect Physiology and Ecology (icipe), P.O Box 30772-00100, Nairobi, Kenya
| | - Daniel K Masiga
- International Centre of Insect Physiology and Ecology (icipe), P.O Box 30772-00100, Nairobi, Kenya
| | - Dickens O Ondifu
- International Centre of Insect Physiology and Ecology (icipe), P.O Box 30772-00100, Nairobi, Kenya
| | - Maurice K Murungi
- International Livestock Research Institute, Old Naivasha Road, P.O Box 30709, Nairobi, 00100, Kenya
| | - Lillian Wambua
- International Livestock Research Institute, Old Naivasha Road, P.O Box 30709, Nairobi, 00100, Kenya
| | - Armanda D S Bastos
- Department of Zoology and Entomology, University of Pretoria, Private Bag 20, Pretoria, 0028, South Africa
| | - Eric M Fèvre
- International Livestock Research Institute, Old Naivasha Road, P.O Box 30709, Nairobi, 00100, Kenya.,Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Leahurst Campus, Chester High Road, Neston, CH64 7TE, UK
| | - Laura C Falzon
- International Livestock Research Institute, Old Naivasha Road, P.O Box 30709, Nairobi, 00100, Kenya. .,Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Leahurst Campus, Chester High Road, Neston, CH64 7TE, UK.
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Getange D, Bargul JL, Kanduma E, Collins M, Bodha B, Denge D, Chiuya T, Githaka N, Younan M, Fèvre EM, Bell-Sakyi L, Villinger J. Ticks and Tick-Borne Pathogens Associated with Dromedary Camels ( Camelus dromedarius) in Northern Kenya. Microorganisms 2021; 9:1414. [PMID: 34209060 PMCID: PMC8306667 DOI: 10.3390/microorganisms9071414] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 06/21/2021] [Accepted: 06/22/2021] [Indexed: 12/17/2022] Open
Abstract
Ticks and tick-borne pathogens (TBPs) are major constraints to camel health and production, yet epidemiological data on their diversity and impact on dromedary camels remain limited. We surveyed the diversity of ticks and TBPs associated with camels and co-grazing sheep at 12 sites in Marsabit County, northern Kenya. We screened blood and ticks (858 pools) from 296 camels and 77 sheep for bacterial and protozoan TBPs by high-resolution melting analysis and sequencing of PCR products. Hyalomma (75.7%), Amblyomma (17.6%) and Rhipicephalus (6.7%) spp. ticks were morphologically identified and confirmed by molecular analyses. We detected TBP DNA in 80.1% of blood samples from 296 healthy camels. "Candidatus Anaplasma camelii", "Candidatus Ehrlichia regneryi" and Coxiella burnetii were detected in both camels and associated ticks, and Ehrlichia chaffeensis, Rickettsia africae, Rickettsia aeschlimannii and Coxiella endosymbionts were detected in camel ticks. We also detected Ehrlichia ruminantium, which is responsible for heartwater disease in ruminants, in Amblyomma ticks infesting camels and sheep and in sheep blood, indicating its endemicity in Marsabit. Our findings also suggest that camels and/or the ticks infesting them are disease reservoirs of zoonotic Q fever (C. burnetii), ehrlichiosis (E. chaffeensis) and rickettsiosis (R. africae), which pose public health threats to pastoralist communities.
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Affiliation(s)
- Dennis Getange
- International Centre of Insect Physiology and Ecology (icipe), Nairobi P.O. Box 30772-00100, Kenya; (D.G.); (T.C.)
- Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology, Nairobi P.O. Box 62000-00200, Kenya
| | - Joel L. Bargul
- International Centre of Insect Physiology and Ecology (icipe), Nairobi P.O. Box 30772-00100, Kenya; (D.G.); (T.C.)
- Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology, Nairobi P.O. Box 62000-00200, Kenya
| | - Esther Kanduma
- Department of Biochemistry, School of Medicine, University of Nairobi, Nairobi P.O. Box 30197-00100, Kenya;
| | - Marisol Collins
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool L3 5RF, UK; (M.C.); (E.M.F.); (L.B.-S.)
| | - Boku Bodha
- Directorate of Veterinary Services, County Government of Marsabit, Marsabit P.O. Box 384-60500, Kenya; (B.B.); (D.D.)
| | - Diba Denge
- Directorate of Veterinary Services, County Government of Marsabit, Marsabit P.O. Box 384-60500, Kenya; (B.B.); (D.D.)
| | - Tatenda Chiuya
- International Centre of Insect Physiology and Ecology (icipe), Nairobi P.O. Box 30772-00100, Kenya; (D.G.); (T.C.)
| | - Naftaly Githaka
- International Livestock Research Institute, Nairobi P.O. Box 30709-00100, Kenya;
| | - Mario Younan
- Food and Agriculture Organization of the United Nations (FAO), Programme & Operational Support to Syria Crisis, UN cross-border hub, Gaziantep 27010, Turkey;
| | - Eric M. Fèvre
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool L3 5RF, UK; (M.C.); (E.M.F.); (L.B.-S.)
- International Livestock Research Institute, Nairobi P.O. Box 30709-00100, Kenya;
| | - Lesley Bell-Sakyi
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool L3 5RF, UK; (M.C.); (E.M.F.); (L.B.-S.)
| | - Jandouwe Villinger
- International Centre of Insect Physiology and Ecology (icipe), Nairobi P.O. Box 30772-00100, Kenya; (D.G.); (T.C.)
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Lipkin WI, Mishra N, Briese T. Screening for Viral Infections. ENCYCLOPEDIA OF VIROLOGY 2021. [PMCID: PMC7836304 DOI: 10.1016/b978-0-12-814515-9.00052-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
This article reviews methods for diagnosis of viral infections including histopathology, culture, nucleic acid tests, and serology. We discuss the principles that underlie individual assays as well as their strengths and limitations. Our intent is to provide insights into selecting strategies for viral diagnosis and discovery that can be pursued by accessing more detailed and granular protocols.
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Kidambasi KO, Masiga DK, Villinger J, Carrington M, Bargul JL. Detection of blood pathogens in camels and their associated ectoparasitic camel biting keds, Hippobosca camelina: the potential application of keds in xenodiagnosis of camel haemopathogens. AAS Open Res 2020; 2:164. [PMID: 32510036 PMCID: PMC7243205 DOI: 10.12688/aasopenres.13021.2] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/11/2020] [Indexed: 12/31/2022] Open
Abstract
Background: Major constraints to camel production include pests and diseases. In northern Kenya, little information is available about blood-borne pathogens circulating in one-humped camels (
Camelus dromedarius) or their possible transmission by the camel haematophagous ectoparasite,
Hippobosca camelina, commonly known as camel ked or camel fly. This study aimed to: (i) identify the presence of potentially insect-vectored pathogens in camels and camel keds, and (ii) assess the potential utility of keds for xenodiagnosis of camel pathogens that they may not vector. Methods: In Laisamis, northern Kenya, camel blood samples (n = 249) and camel keds (n = 117) were randomly collected from camels. All samples were screened for trypanosomal and camelpox DNA by PCR, and for
Anaplasma, Ehrlichia, Brucella, Coxiella, Theileria, and
Babesia by PCR coupled with high-resolution melting (PCR-HRM) analysis. Results: In camels, we detected
Trypanosoma vivax (41%),
Trypanosoma evansi (1.2%), and “
Candidatus Anaplasma camelii” (68.67%). In camel keds, we also detected
T. vivax (45.3%),
T. evansi (2.56%),
Trypanosoma melophagium (1/117) (0.4%), and “
Candidatus Anaplasma camelii” (16.24 %). Piroplasms (
Theileria spp. and
Babesia spp.),
Coxiella burnetii,
Brucella spp.,
Ehrlichia spp., and camel pox were not detected in any samples. Conclusions: This study reveals the presence of epizootic pathogens in camels from northern Kenya. Furthermore, the presence of the same pathogens in camels and in keds collected from sampled camels suggests the potential use of these flies in xenodiagnosis of haemopathogens circulating in camels.
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Affiliation(s)
- Kevin O Kidambasi
- Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Nairobi, P.O.Box 62000-00200, Kenya.,Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Nairobi, P.O.Box 62000-00200, Kenya.,Animal Health Department/Molecular Biology and Bioinformatics Unit, International Centre of Insect Physiology and Ecology, Nairobi, P.O. Box 30772-00100, Kenya.,Animal Health Department/Molecular Biology and Bioinformatics Unit, International Centre of Insect Physiology and Ecology, Nairobi, P.O. Box 30772-00100, Kenya
| | - Daniel K Masiga
- Animal Health Department/Molecular Biology and Bioinformatics Unit, International Centre of Insect Physiology and Ecology, Nairobi, P.O. Box 30772-00100, Kenya.,Animal Health Department/Molecular Biology and Bioinformatics Unit, International Centre of Insect Physiology and Ecology, Nairobi, P.O. Box 30772-00100, Kenya
| | - Jandouwe Villinger
- Animal Health Department/Molecular Biology and Bioinformatics Unit, International Centre of Insect Physiology and Ecology, Nairobi, P.O. Box 30772-00100, Kenya.,Animal Health Department/Molecular Biology and Bioinformatics Unit, International Centre of Insect Physiology and Ecology, Nairobi, P.O. Box 30772-00100, Kenya
| | - Mark Carrington
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK.,Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK
| | - Joel L Bargul
- Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Nairobi, P.O.Box 62000-00200, Kenya.,Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Nairobi, P.O.Box 62000-00200, Kenya.,Animal Health Department/Molecular Biology and Bioinformatics Unit, International Centre of Insect Physiology and Ecology, Nairobi, P.O. Box 30772-00100, Kenya.,Animal Health Department/Molecular Biology and Bioinformatics Unit, International Centre of Insect Physiology and Ecology, Nairobi, P.O. Box 30772-00100, Kenya
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8
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Kidambasi KO, Masiga DK, Villinger J, Carrington M, Bargul JL. Detection of blood pathogens in camels and their associated ectoparasitic camel biting keds, Hippobosca camelina: the potential application of keds in xenodiagnosis of camel haemopathogens. AAS Open Res 2020; 2:164. [PMID: 32510036 DOI: 10.12688/aasopenres.13021.1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/30/2019] [Indexed: 11/20/2022] Open
Abstract
Background: Major constraints to camel production include pests and diseases. In northern Kenya, little information is available about blood-borne pathogens circulating in one-humped camels ( Camelus dromedarius) or their possible transmission by the camel haematophagous ectoparasite, Hippobosca camelina, commonly known as camel ked or camel fly. This study aimed to: (i) identify the presence of potentially insect-vectored pathogens in camels and camel keds, and (ii) assess the potential utility of keds for xenodiagnosis of camel pathogens that they may not vector. Methods: In Laisamis, northern Kenya, camel blood samples (n = 249) and camel keds (n = 117) were randomly collected from camels. All samples were screened for trypanosomal and camelpox DNA by PCR, and for Anaplasma, Ehrlichia, Brucella, Coxiella, Theileria, and Babesia by PCR coupled with high-resolution melting (PCR-HRM) analysis. Results: In camels, we detected Trypanosoma vivax (41%), Trypanosoma evansi (1.2%), and " Candidatus Anaplasma camelii" (68.67%). In camel keds, we also detected T. vivax (45.3%), T. evansi (2.56%), Trypanosoma melophagium (1/117) (0.4%), and " Candidatus Anaplasma camelii" (16.24 %). Piroplasms ( Theileria spp. and Babesia spp.), Coxiella burnetii, Brucella spp., Ehrlichia spp., and camel pox were not detected in any samples. Conclusions: This study reveals the presence of epizootic pathogens in camels from northern Kenya. Furthermore, the presence of the same pathogens in camels and in keds collected from sampled camels suggests the potential use of these flies in xenodiagnosis of haemopathogens circulating in camels.
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Affiliation(s)
- Kevin O Kidambasi
- Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Nairobi, P.O.Box 62000-00200, Kenya.,Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Nairobi, P.O.Box 62000-00200, Kenya.,Animal Health Department/Molecular Biology and Bioinformatics Unit, International Centre of Insect Physiology and Ecology, Nairobi, P.O. Box 30772-00100, Kenya.,Animal Health Department/Molecular Biology and Bioinformatics Unit, International Centre of Insect Physiology and Ecology, Nairobi, P.O. Box 30772-00100, Kenya
| | - Daniel K Masiga
- Animal Health Department/Molecular Biology and Bioinformatics Unit, International Centre of Insect Physiology and Ecology, Nairobi, P.O. Box 30772-00100, Kenya.,Animal Health Department/Molecular Biology and Bioinformatics Unit, International Centre of Insect Physiology and Ecology, Nairobi, P.O. Box 30772-00100, Kenya
| | - Jandouwe Villinger
- Animal Health Department/Molecular Biology and Bioinformatics Unit, International Centre of Insect Physiology and Ecology, Nairobi, P.O. Box 30772-00100, Kenya.,Animal Health Department/Molecular Biology and Bioinformatics Unit, International Centre of Insect Physiology and Ecology, Nairobi, P.O. Box 30772-00100, Kenya
| | - Mark Carrington
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK.,Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK
| | - Joel L Bargul
- Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Nairobi, P.O.Box 62000-00200, Kenya.,Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Nairobi, P.O.Box 62000-00200, Kenya.,Animal Health Department/Molecular Biology and Bioinformatics Unit, International Centre of Insect Physiology and Ecology, Nairobi, P.O. Box 30772-00100, Kenya.,Animal Health Department/Molecular Biology and Bioinformatics Unit, International Centre of Insect Physiology and Ecology, Nairobi, P.O. Box 30772-00100, Kenya
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9
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Jado I, Escudero R, Espigares B, Lara E, Rodriguez-Vargas M, Garcia-Amil C, Lobo B, Rodriguez-Moreno I, Toledo A. Rapid and Highly Sensitive DNA Flow Technology Platform to Detect Tick-Borne Bacterial Pathogens in Clinical Samples. Vector Borne Zoonotic Dis 2020; 20:107-116. [DOI: 10.1089/vbz.2019.2470] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Affiliation(s)
- Isabel Jado
- Laboratorio de Referencia e Investigación en Patógenos Especiales, Centro Nacional de Microbiología, Instituto de Salud Carlos III. Majadahonda, Madrid, Spain
| | - Raquel Escudero
- Laboratorio de Referencia e Investigación en Patógenos Especiales, Centro Nacional de Microbiología, Instituto de Salud Carlos III. Majadahonda, Madrid, Spain
| | | | | | - Manuela Rodriguez-Vargas
- Laboratorio de Referencia e Investigación en Patógenos Especiales, Centro Nacional de Microbiología, Instituto de Salud Carlos III. Majadahonda, Madrid, Spain
| | - Cristina Garcia-Amil
- Laboratorio de Referencia e Investigación en Patógenos Especiales, Centro Nacional de Microbiología, Instituto de Salud Carlos III. Majadahonda, Madrid, Spain
| | - Bruno Lobo
- Laboratorio de Referencia e Investigación en Patógenos Especiales, Centro Nacional de Microbiología, Instituto de Salud Carlos III. Majadahonda, Madrid, Spain
| | - Isabel Rodriguez-Moreno
- Laboratorio de Referencia e Investigación en Patógenos Especiales, Centro Nacional de Microbiología, Instituto de Salud Carlos III. Majadahonda, Madrid, Spain
| | - Alvaro Toledo
- Department of Entomology, Center for Vector Biology, Rutgers University, New Brunswick, New Jersey
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10
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Sanchez-Vicente S, Tagliafierro T, Coleman JL, Benach JL, Tokarz R. Polymicrobial Nature of Tick-Borne Diseases. mBio 2019; 10:e02055-19. [PMID: 31506314 PMCID: PMC6737246 DOI: 10.1128/mbio.02055-19] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Accepted: 08/07/2019] [Indexed: 01/08/2023] Open
Abstract
Tick-borne diseases have doubled in the last 12 years, and their geographic distribution has spread as well. The clinical spectrum of tick-borne diseases can range from asymptomatic to fatal infections, with a disproportionate incidence in children and the elderly. In the last few years, new agents have been discovered, and genetic changes have helped in the spread of pathogens and ticks. Polymicrobial infections, mostly in Ixodes scapularis, can complicate diagnostics and augment disease severity. Amblyomma americanum ticks have expanded their range, resulting in a dynamic and complex situation, possibly fueled by climate change. To document these changes, using molecular biology strategies for pathogen detection, an assessment of 12 microbes (9 pathogens and 3 symbionts) in three species of ticks was done in Suffolk County, New York. At least one agent was detected in 63% of I. scapularis ticksBorrelia burgdorferi was the most prevalent pathogen (57% in adults; 27% in nymphs), followed by Babesia microti (14% in adults; 15% in nymphs), Anaplasma phagocytophilum (14% in adults; 2% in nymphs), Borrelia miyamotoi (3% in adults), and Powassan virus (2% in adults). Polymicrobial infections were detected in 22% of I. scapularis ticks, with coinfections of B. burgdorferi and B. microti (9%) and of B. burgdorferi and A. phagocytophilum (7%). Three Ehrlichia species were detected in 4% of A. americanum ticks. The rickettsiae constituted the largest prokaryotic biomass of all the ticks tested and included Rickettsia amblyommatis, Rickettsia buchneri, and Rickettsia montanensis The high rates of polymicrobial infection in ticks present an opportunity to study the biological interrelationships of pathogens and their vectors.IMPORTANCE Tick-borne diseases have increased in prevalence in the United States and abroad. The reasons for these increases are multifactorial, but climate change is likely to be a major factor. One of the main features of the increase is the geographic expansion of tick vectors, notably Amblyomma americanum, which has brought new pathogens to new areas. The clinical spectrum of tick-borne diseases can range from asymptomatic to fatal infections, with a disproportionate incidence in children and the elderly. In addition, new pathogens that are cotransmitted by Ixodes scapularis have been discovered and have led to difficult diagnoses and to disease severity. Of these, Borrelia burgdorferi, the agent of Lyme disease, continues to be the most frequently transmitted pathogen. However, Babesia microti, Borrelia miyamotoi (another spirochete), Anaplasma phagocytophilum, and Powassan virus are frequent cotransmitted agents. Polymicrobial infection has important consequences for the diagnosis and management of tick-borne diseases.
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Affiliation(s)
- Santiago Sanchez-Vicente
- Department of Molecular Genetics and Microbiology and Center for Infectious Diseases, Stony Brook University, Stony Brook, New York, USA
| | - Teresa Tagliafierro
- Center for Infection and Immunity, Mailman School of Public Health, Columbia University, New York, New York, USA
| | - James L Coleman
- Department of Molecular Genetics and Microbiology and Center for Infectious Diseases, Stony Brook University, Stony Brook, New York, USA
| | - Jorge L Benach
- Department of Molecular Genetics and Microbiology and Center for Infectious Diseases, Stony Brook University, Stony Brook, New York, USA
| | - Rafal Tokarz
- Center for Infection and Immunity, Mailman School of Public Health, Columbia University, New York, New York, USA
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11
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Graham CB, Maes SE, Hojgaard A, Fleshman AC, Sheldon SW, Eisen RJ. A molecular algorithm to detect and differentiate human pathogens infecting Ixodes scapularis and Ixodes pacificus (Acari: Ixodidae). Ticks Tick Borne Dis 2018; 9:390-403. [PMID: 29258802 PMCID: PMC6452875 DOI: 10.1016/j.ttbdis.2017.12.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 11/21/2017] [Accepted: 12/06/2017] [Indexed: 12/23/2022]
Abstract
The incidence and geographic range of tick-borne illness associated with Ixodes scapularis and Ixodes pacificus have dramatically increased in recent decades. Anaplasmosis, babesiosis, and Borrelia spirochete infections, including Lyme borreliosis, account for tens of thousands of reported cases of tick-borne disease every year. Assays that reliably detect pathogens in ticks allow investigators and public health agencies to estimate the geographic distribution of human pathogens, assess geographic variation in their prevalence, and evaluate the effectiveness of prevention strategies. As investigators continue to describe new species within the Borrelia burgdorferi sensu lato complex and to recognize some Ixodes-borne Borrelia species as human pathogens, assays are needed to detect and differentiate these species. Here we describe an algorithm to detect and differentiate pathogens in unfed I. scapularis and I. pacificus nymphs including Anaplasma phagocytophilum, Babesia microti, Borrelia burgdorferi sensu stricto, Borrelia mayonii, and Borrelia miyamotoi. The algorithm comprises 5 TaqMan real-time polymerase chain reaction assays and 3 sequencing protocols. It employs multiple targets for each pathogen to optimize specificity, a gene target for I. scapularis and I. pacificus to verify tick-derived DNA quality, and a pan-Borrelia target to detect Borrelia species that may emerge as human disease agents in the future. We assess the algorithm's sensitivity, specificity, and performance on field-collected ticks.
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Affiliation(s)
- Christine B Graham
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, 3156 Rampart Rd., Fort Collins, CO 80521, United States.
| | - Sarah E Maes
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, 3156 Rampart Rd., Fort Collins, CO 80521, United States
| | - Andrias Hojgaard
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, 3156 Rampart Rd., Fort Collins, CO 80521, United States
| | - Amy C Fleshman
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, 3156 Rampart Rd., Fort Collins, CO 80521, United States
| | - Sarah W Sheldon
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, 3156 Rampart Rd., Fort Collins, CO 80521, United States
| | - Rebecca J Eisen
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, 3156 Rampart Rd., Fort Collins, CO 80521, United States
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12
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Ndeereh D, Muchemi G, Thaiyah A, Otiende M, Angelone-Alasaad S, Jowers MJ. Molecular survey of Coxiella burnetii in wildlife and ticks at wildlife-livestock interfaces in Kenya. EXPERIMENTAL & APPLIED ACAROLOGY 2017; 72:277-289. [PMID: 28593481 DOI: 10.1007/s10493-017-0146-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 05/27/2017] [Indexed: 06/07/2023]
Abstract
Coxiella burnetii is the causative agent of Q fever, a zoonotic disease of public health importance. The role of wildlife and their ticks in the epidemiology of C. burnetii in Kenya is unknown. This study analysed the occurrence and prevalence of the pathogen in wildlife and their ticks at two unique wildlife-livestock interfaces of Laikipia and Maasai Mara National Reserve (MMNR) with the aim to determine the potential risk of transmission to livestock and humans. Blood from 79 and 73 animals in Laikipia and MMNR, respectively, and 756 and 95 ixodid ticks in each of the areas, respectively, was analysed. Ticks were pooled before analyses into 137 and 29 samples in Laikipia and MMNR, respectively, of one to eight non-engorged ticks according to species and animal host. Real-time PCR amplifying the repetitive insertion element IS1111a of the transposase gene was used to detect C. burnetii DNA. Although none of the animals and ticks from MMNR tested positive, ticks from Laikipia had an overall pooled prevalence of 2.92% resulting in a maximum-likelihood estimate of prevalence of 0.54%, 95% CI 0.17-1.24. Ticks positive for C. burnetii DNA belonged to the genus Rhipicephalus at a pooled prevalence of 2.96% (maximum-likelihood estimate of prevalence of 0.54%, 95% CI 0.17-1.26). These ticks were Rhipicephalus appendiculatus, R. pulchellus and R. evertsi at pooled prevalence of 3.77, 3.03 and 2.04%, respectively. The presence of C. burnetii in ticks suggests circulation of the pathogen in Laikipia and demonstrates they may play a potential role in the epidemiology of Q fever in this ecosystem. The findings warrant further studies to understand the presence of C. burnetii in domestic animals and their ticks within both study areas.
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Affiliation(s)
- David Ndeereh
- Department of Veterinary Services, Kenya Wildlife Service, P.O. Box 40241-00100, Nairobi, Kenya.
| | - Gerald Muchemi
- Department of Public Health, Pharmacology and Toxicology, Faculty of Veterinary Medicine, University of Nairobi, P.O. Box 29053-00625, Nairobi, Kenya
| | - Andrew Thaiyah
- Department of Clinical Studies, Faculty of Veterinary Medicine, University of Nairobi, P.O. Box 29053-00625, Nairobi, Kenya
| | - Moses Otiende
- Department of Veterinary Services, Kenya Wildlife Service, P.O. Box 40241-00100, Nairobi, Kenya
| | - Samer Angelone-Alasaad
- Institute of Evolutionary Biology and Environmental Studies (IEU), University of Zürich, Winterthurerstrasse 190, 8057, Zurich, Switzerland
| | - Michael J Jowers
- CIBIO/InBIO (Centro de Investigação em Biodiversidade e Recursos Genéticos), Universidade do Porto, Campus Agrario De Vairão, 4485-661, Vairão, Portugal.
- National Institute of Ecology, 1210, Geumgang-ro, Maseo-myeon, Seocheon-gun, Chungcheongnam-do, 33657, Korea.
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13
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Abstract
Lyme disease is caused by the bacterium Borrelia burgdorferi and is transmitted to humans through the bite of infected blacklegged ticks. According to the Centers for Disease Control and Prevention, it is the most commonly reported vector-borne illness and the fifth most common disease in the National Notifiable Diseases Surveillance System. If left untreated, infection disseminates to the nervous system. The nonhuman primate model of Lyme disease of the nervous system, or Lyme neuroborreliosis, accurately mimics the aspects of the human illness. There is general recognition for the potential of infectious-related autoimmune inflammatory processes contributing to disease progression and clinical manifestations.
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Affiliation(s)
- David S Younger
- Division of Neuroepidemiology, Department of Neurology, New York University School of Medicine, New York, NY, USA; College of Global Public Health, New York University, New York, NY, USA.
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14
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Omondi D, Masiga DK, Fielding BC, Kariuki E, Ajamma YU, Mwamuye MM, Ouso DO, Villinger J. Molecular Detection of Tick-Borne Pathogen Diversities in Ticks from Livestock and Reptiles along the Shores and Adjacent Islands of Lake Victoria and Lake Baringo, Kenya. Front Vet Sci 2017; 4:73. [PMID: 28620610 PMCID: PMC5451513 DOI: 10.3389/fvets.2017.00073] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Accepted: 04/27/2017] [Indexed: 11/25/2022] Open
Abstract
Although diverse tick-borne pathogens (TBPs) are endemic to East Africa, with recognized impact on human and livestock health, their diversity and specific interactions with tick and vertebrate host species remain poorly understood in the region. In particular, the role of reptiles in TBP epidemiology remains unknown, despite having been implicated with TBPs of livestock among exported tortoises and lizards. Understanding TBP ecologies, and the potential role of common reptiles, is critical for the development of targeted transmission control strategies for these neglected tropical disease agents. During the wet months (April-May; October-December) of 2012-2013, we surveyed TBP diversity among 4,126 ticks parasitizing livestock and reptiles at homesteads along the shores and islands of Lake Baringo and Lake Victoria in Kenya, regions endemic to diverse neglected tick-borne diseases. After morphological identification of 13 distinct Rhipicephalus, Amblyomma, and Hyalomma tick species, ticks were pooled (≤8 individuals) by species, host, sampling site, and collection date into 585 tick pools. By supplementing previously established molecular assays for TBP detection with high-resolution melting analysis of PCR products before sequencing, we identified high frequencies of potential disease agents of ehrlichiosis (12.48% Ehrlichia ruminantium, 9.06% Ehrlichia canis), anaplasmosis (6.32% Anaplasma ovis, 14.36% Anaplasma platys, and 3.08% Anaplasma bovis,), and rickettsiosis (6.15% Rickettsia africae, 2.22% Rickettsia aeschlimannii, 4.27% Rickettsia rhipicephali, and 4.95% Rickettsia spp.), as well as Paracoccus sp. and apicomplexan hemoparasites (0.51% Theileria sp., 2.56% Hepatozoon fitzsimonsi, and 1.37% Babesia caballi) among tick pools. Notably, we identified E. ruminantium in both Amblyomma and Rhipicephalus pools of ticks sampled from livestock in both study areas as well as in Amblyomma falsomarmoreum (66.7%) and Amblyomma nuttalli (100%) sampled from tortoises and Amblyomma sparsum (63.6%) sampled in both cattle and tortoises at Lake Baringo. Similarly, we identified E. canis in rhipicephaline ticks sampled from livestock and dogs in both regions and Amblyomma latum (75%) sampled from monitor lizards at Lake Victoria. These novel tick-host-pathogen interactions have implications on the risk of disease transmission to humans and domestic animals and highlight the complexity of TBP ecologies, which may include reptiles as reservoir species, in sub-Saharan Africa.
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Affiliation(s)
- David Omondi
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
- University of Western Cape, Bellville, South Africa
- Egerton University, Egerton, Kenya
| | - Daniel K. Masiga
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | | | | | - Yvonne Ukamaka Ajamma
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
- Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
| | - Micky M. Mwamuye
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | - Daniel O. Ouso
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
- Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
| | - Jandouwe Villinger
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
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15
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Novel Rickettsia and emergent tick-borne pathogens: A molecular survey of ticks and tick-borne pathogens in Shimba Hills National Reserve, Kenya. Ticks Tick Borne Dis 2016; 8:208-218. [PMID: 28011185 DOI: 10.1016/j.ttbdis.2016.09.002] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Revised: 09/01/2016] [Accepted: 09/03/2016] [Indexed: 11/23/2022]
Abstract
Ticks are important vectors of emerging and re-emerging zoonoses, the majority of which originate from wildlife. In recent times, this has become a global public health concern that necessitates surveillance of both known and unknown tick-borne pathogens likely to be future disease threats, as well as their tick vectors. We carried out a survey of the diversity of ticks and tick-borne pathogens in Kenya's Shimba Hills National Reserve (SHNR), an area with intensified human-livestock-wildlife interactions, where we collected 4297 questing ticks (209 adult ticks, 586 nymphs and 3502 larvae). We identified four tick species of two genera (Amblyomma eburneum, Amblyomma tholloni, Rhipicephalus maculatus and a novel Rhipicephalus sp.) based on both morphological characteristics and molecular analysis of 16S rRNA, internal transcribed spacer 2 (ITS 2) and cytochrome oxidase subunit 1 (CO1) genes. We pooled the ticks (3-8 adults, 8-15 nymphs or 30 larvae) depending on species and life-cycle stages, and screened for bacterial, arboviral and protozoal pathogens using PCR with high-resolution melting analysis and sequencing of unique melt profiles. We report the first molecular detection of Anaplasma phagocytophilum, a novel Rickettsia-like and Ehrlichia-like species, in Rh. maculatus ticks. We also detected Ehrlichia chaffeensis, Coxiella sp., Rickettsia africae and Theileria velifera in Am. eburneum ticks for the first time. Our findings demonstrate previously unidentified tick-pathogen relationships and a unique tick diversity in the SHNR that may contribute to livestock, and possibly human, morbidity in the region. This study highlights the importance of routine surveillance in similar areas to elucidate disease transmission dynamics, as a critical component to inform the development of better tick-borne disease diagnosis, prevention and control measures.
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16
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Nelder MP, Russell CB, Sheehan NJ, Sander B, Moore S, Li Y, Johnson S, Patel SN, Sider D. Human pathogens associated with the blacklegged tick Ixodes scapularis: a systematic review. Parasit Vectors 2016; 9:265. [PMID: 27151067 PMCID: PMC4857413 DOI: 10.1186/s13071-016-1529-y] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Accepted: 04/21/2016] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND The blacklegged tick Ixodes scapularis transmits Borrelia burgdorferi (sensu stricto) in eastern North America; however, the agent of Lyme disease is not the sole pathogen harbored by the blacklegged tick. The blacklegged tick is expanding its range into areas of southern Canada such as Ontario, an area where exposure to blacklegged tick bites and tick-borne pathogens is increasing. We performed a systematic review to evaluate the public health risks posed by expanding blacklegged tick populations and their associated pathogens. METHODS We followed PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines for conducting our systematic review. We searched Ovid MEDLINE, Embase, BIOSIS, Scopus and Environment Complete databases for studies published from 2000 through 2015, using subject headings and keywords that included "Ixodes scapularis", "Rickettsia", "Borrelia", "Anaplasma", "Babesia" and "pathogen." Two reviewers screened titles and abstracts against eligibility criteria (i.e. studies that included field-collected blacklegged ticks and studies that did not focus solely on B. burgdorferi) and performed quality assessments on eligible studies. RESULTS Seventy-eight studies were included in the final review, 72 were from the US and eight were from Canada (two studies included blacklegged ticks from both countries). Sixty-four (82%) studies met ≥ 75% of the quality assessment criteria. Blacklegged ticks harbored 91 distinct taxa, 16 of these are tick-transmitted human pathogens, including species of Anaplasma, Babesia, Bartonella, Borrelia, Ehrlichia, Rickettsia, Theileria and Flavivirus. Organism richness was highest in the Northeast (Connecticut, New York) and Upper Midwest US (Wisconsin); however, organism richness was dependent on sampling effort. The primary tick-borne pathogens of public health concern in Ontario, due to the geographic proximity or historical detection in Ontario, are Anaplasma phagocytophilum, Babesia microti, B. burgdorferi, Borrelia miyamotoi, deer tick virus and Ehrlichia muris-like sp. Aside from B. burgdorferi and to a much lesser concern A. phagocytophilum, these pathogens are not immediate concerns to public health in Ontario; rather they represent future threats as the distribution of vectors and pathogens continue to proliferate. CONCLUSIONS Our review is the first systematic assessment of the literature on the human pathogens associated with the blacklegged tick. As Lyme disease awareness continues to increase, it is an opportune time to document the full spectrum of human pathogens transmittable by blacklegged ticks.
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Affiliation(s)
- Mark P Nelder
- Enteric, Zoonotic and Vector-borne Diseases; Communicable Diseases, Emergency Preparedness and Response; Public Health Ontario, Toronto, Ontario, Canada.
| | - Curtis B Russell
- Enteric, Zoonotic and Vector-borne Diseases; Communicable Diseases, Emergency Preparedness and Response; Public Health Ontario, Toronto, Ontario, Canada
| | - Nina Jain Sheehan
- Enteric, Zoonotic and Vector-borne Diseases; Communicable Diseases, Emergency Preparedness and Response; Public Health Ontario, Toronto, Ontario, Canada
| | - Beate Sander
- Enteric, Zoonotic and Vector-borne Diseases; Communicable Diseases, Emergency Preparedness and Response; Public Health Ontario, Toronto, Ontario, Canada
- Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, ON, Canada
- Institute for Clinical Evaluative Sciences, Toronto, ON, Canada
| | - Stephen Moore
- Enteric, Zoonotic and Vector-borne Diseases; Communicable Diseases, Emergency Preparedness and Response; Public Health Ontario, Toronto, Ontario, Canada
| | - Ye Li
- Analytic Services, Knowledge Services, Public Health Ontario, Toronto, ON, Canada
| | - Steven Johnson
- Analytic Services, Knowledge Services, Public Health Ontario, Toronto, ON, Canada
| | - Samir N Patel
- Public Health Ontario Laboratories, Public Health Ontario, Toronto, ON, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
| | - Doug Sider
- Enteric, Zoonotic and Vector-borne Diseases; Communicable Diseases, Emergency Preparedness and Response; Public Health Ontario, Toronto, Ontario, Canada
- Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, ON, Canada
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17
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Tadin A, Tokarz R, Markotić A, Margaletić J, Turk N, Habuš J, Svoboda P, Vucelja M, Desai A, Jain K, Lipkin WI. Molecular Survey of Zoonotic Agents in Rodents and Other Small Mammals in Croatia. Am J Trop Med Hyg 2015; 94:466-73. [PMID: 26711522 DOI: 10.4269/ajtmh.15-0517] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Accepted: 11/02/2015] [Indexed: 11/07/2022] Open
Abstract
Croatia is a focus for many rodent-borne zoonosis. Here, we report a survey of 242 rodents and small mammals, including 43 Myodes glareolus, 131 Apodemus flavicollis, 53 Apodemus agrarius, three Apodemus sylvaticus, six Sorex araneus, four Microtus arvalis, one Microtus agrestis, and one Muscardinus avellanarius, collected at eight sites in Croatia over an 8-year period. Multiplex MassTag polymerase chain reaction (PCR) was used for detection of Borrelia, Rickettsia, Bartonella, Babesia, Ehrlichia, Anaplasma, Francisella tularensis, and Coxiella burnetii. Individual PCR assays were used for detection of Leptospira, lymphocytic choriomeningitis virus, orthopoxviruses, flaviviruses, hantaviruses, and Toxoplasma gondii. Of the rodents, 52 (21.5%) were infected with Leptospira, 9 (3.7%) with Borrelia miyamotoi, 5 (2%) with Borrelia afzelii, 29 (12.0%) with Bartonella, 8 (3.3%) with Babesia microti, 2 (0.8%) with Ehrlichia, 4 (1.7%) with Anaplasma, 2 (0.8%) with F. tularensis, 43 (17.8%) with hantaviruses, and 1 (0.4%) with an orthopoxvirus. Other agents were not detected. Multiple infections were found in 32 rodents (13.2%): dual infections in 26 rodents (10.7%), triple infections in four rodents (2.9%), and quadruple infections in two rodents (0.8%). Our findings indicate that rodents in Croatia harbor a wide range of bacteria and viruses that are pathogenic to humans.
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Affiliation(s)
- Ante Tadin
- University Hospital for Infectious Diseases "Dr. Fran Mihaljević," Zagreb, Croatia; Center for Infection and Immunity, Mailman School of Public Health, Columbia University, New York, New York; Faculty of Forestry, University of Zagreb, Zagreb, Croatia; Faculty of Veterinary Medicine, University of Zagreb, Zagreb, Croatia
| | - Rafal Tokarz
- University Hospital for Infectious Diseases "Dr. Fran Mihaljević," Zagreb, Croatia; Center for Infection and Immunity, Mailman School of Public Health, Columbia University, New York, New York; Faculty of Forestry, University of Zagreb, Zagreb, Croatia; Faculty of Veterinary Medicine, University of Zagreb, Zagreb, Croatia
| | - Alemka Markotić
- University Hospital for Infectious Diseases "Dr. Fran Mihaljević," Zagreb, Croatia; Center for Infection and Immunity, Mailman School of Public Health, Columbia University, New York, New York; Faculty of Forestry, University of Zagreb, Zagreb, Croatia; Faculty of Veterinary Medicine, University of Zagreb, Zagreb, Croatia
| | - Josip Margaletić
- University Hospital for Infectious Diseases "Dr. Fran Mihaljević," Zagreb, Croatia; Center for Infection and Immunity, Mailman School of Public Health, Columbia University, New York, New York; Faculty of Forestry, University of Zagreb, Zagreb, Croatia; Faculty of Veterinary Medicine, University of Zagreb, Zagreb, Croatia
| | - Nenad Turk
- University Hospital for Infectious Diseases "Dr. Fran Mihaljević," Zagreb, Croatia; Center for Infection and Immunity, Mailman School of Public Health, Columbia University, New York, New York; Faculty of Forestry, University of Zagreb, Zagreb, Croatia; Faculty of Veterinary Medicine, University of Zagreb, Zagreb, Croatia
| | - Josipa Habuš
- University Hospital for Infectious Diseases "Dr. Fran Mihaljević," Zagreb, Croatia; Center for Infection and Immunity, Mailman School of Public Health, Columbia University, New York, New York; Faculty of Forestry, University of Zagreb, Zagreb, Croatia; Faculty of Veterinary Medicine, University of Zagreb, Zagreb, Croatia
| | - Petra Svoboda
- University Hospital for Infectious Diseases "Dr. Fran Mihaljević," Zagreb, Croatia; Center for Infection and Immunity, Mailman School of Public Health, Columbia University, New York, New York; Faculty of Forestry, University of Zagreb, Zagreb, Croatia; Faculty of Veterinary Medicine, University of Zagreb, Zagreb, Croatia
| | - Marko Vucelja
- University Hospital for Infectious Diseases "Dr. Fran Mihaljević," Zagreb, Croatia; Center for Infection and Immunity, Mailman School of Public Health, Columbia University, New York, New York; Faculty of Forestry, University of Zagreb, Zagreb, Croatia; Faculty of Veterinary Medicine, University of Zagreb, Zagreb, Croatia
| | - Aaloki Desai
- University Hospital for Infectious Diseases "Dr. Fran Mihaljević," Zagreb, Croatia; Center for Infection and Immunity, Mailman School of Public Health, Columbia University, New York, New York; Faculty of Forestry, University of Zagreb, Zagreb, Croatia; Faculty of Veterinary Medicine, University of Zagreb, Zagreb, Croatia
| | - Komal Jain
- University Hospital for Infectious Diseases "Dr. Fran Mihaljević," Zagreb, Croatia; Center for Infection and Immunity, Mailman School of Public Health, Columbia University, New York, New York; Faculty of Forestry, University of Zagreb, Zagreb, Croatia; Faculty of Veterinary Medicine, University of Zagreb, Zagreb, Croatia
| | - W Ian Lipkin
- University Hospital for Infectious Diseases "Dr. Fran Mihaljević," Zagreb, Croatia; Center for Infection and Immunity, Mailman School of Public Health, Columbia University, New York, New York; Faculty of Forestry, University of Zagreb, Zagreb, Croatia; Faculty of Veterinary Medicine, University of Zagreb, Zagreb, Croatia
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Hsu CC, Tokarz R, Briese T, Tsai HC, Quan PL, Lipkin WI. Use of staged molecular analysis to determine causes of unexplained central nervous system infections. Emerg Infect Dis 2014; 19:1470-7. [PMID: 23965845 PMCID: PMC3810931 DOI: 10.3201/eid1909.130474] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
No agent is implicated in most central nervous system (CNS) infections. To investigate cerebrospinal fluid samples from patients with CNS infections of unknown cause in 1 hospital in Taiwan, we used a staged molecular approach, incorporating techniques including multiplex MassTag PCR, 16S rRNA PCR, DNA microarray, and high-throughput pyrosequencing. We determined the infectious agent for 31 (24%) of 131 previously negative samples. Candidate pathogens were identified for 25 (27%) of 94 unexplained meningitis cases and 6 (16%) of 37 unexplained encephalitis cases. Epstein-Barr virus (18 infections) accounted for most of the identified agents in unexplained meningitis cases, followed by Escherichia coli (5), enterovirus (2), human herpesvirus 2 (1), and Mycobacterium tuberculosis. Herpesviruses were identified in samples from patients with unexplained encephalitis cases, including varicella-zoster virus (3 infections), human herpesvirus 1 (2), and cytomegalovirus (1). Our study confirms the power of multiplex MassTag PCR as a rapid diagnostic tool for identifying pathogens causing unexplained CNS infections.
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Kaslow RA, Stanberry LR, Le Duc JW. Diagnosis, Discovery and Dissection of Viral Diseases. VIRAL INFECTIONS OF HUMANS 2014. [PMCID: PMC7122662 DOI: 10.1007/978-1-4899-7448-8_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Richard A. Kaslow
- Department of Epidemiology, University of Alabama, Birmingham School of Public Health, Birmingham, Alabama USA
| | - Lawrence R. Stanberry
- Departmant of Pediatrics, Columbia University College of Physicians and Surgeons, New York, New York USA
| | - James W. Le Duc
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas USA
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Chan K, Marras SAE, Parveen N. Sensitive multiplex PCR assay to differentiate Lyme spirochetes and emerging pathogens Anaplasma phagocytophilum and Babesia microti. BMC Microbiol 2013; 13:295. [PMID: 24359556 PMCID: PMC3890647 DOI: 10.1186/1471-2180-13-295] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Accepted: 12/12/2013] [Indexed: 12/24/2022] Open
Abstract
Background The infection with Borrelia burgdorferi can result in acute to chronic Lyme disease. In addition, coinfection with tick-borne pathogens, Babesia species and Anaplasma phagocytophilum has been increasing in endemic regions of the USA and Europe. The currently used serological diagnostic tests are often difficult to interpret and, moreover, antibodies against the pathogens persist for a long time making it difficult to confirm the cure of the disease. In addition, these tests cannot be used for diagnosis of early disease state before the adaptive immune response is established. Since nucleic acids of the pathogens do not persist after the cure, DNA-based diagnostic tests are becoming highly useful for detecting infectious diseases. Results In this study, we describe a real-time multiplex PCR assay to detect the presence of B. burgdorferi, B. microti and A. phagocytophilum simultaneously even when they are present in very low copy numbers. Interestingly, this quantitative PCR technique is also able to differentiate all three major Lyme spirochete species, B. burgdorferi, B. afzelii, and B. garinii by utilizing a post-PCR denaturation profile analysis and a single molecular beacon probe. This could be very useful for diagnosis and discrimination of various Lyme spirochetes in European countries where all three Lyme spirochete species are prevalent. As proof of the principle for patient samples, we detected the presence of low number of Lyme spirochetes spiked in the human blood using our assay. Finally, our multiplex assay can detect all three tick-borne pathogens in a sensitive and specific manner irrespective of the level of each pathogen present in the sample. We anticipate that this novel diagnostic method will be able to simultaneously diagnose early to chronic stages of Lyme disease, babesiosis and anaplasmosis using the patients’ blood samples. Conclusion Real-time quantitative PCR using specific primers and molecular beacon probes for the selected amplicon described in this study can detect three tick-borne pathogens simultaneously in an accurate manner.
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Affiliation(s)
| | | | - Nikhat Parveen
- Department of Microbiology and Molecular Genetics, Rutgers-New Jersey Medical School, 225 Warren Street, Newark, NJ 07103-3535, USA.
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DGGE Identification of Microorganisms Associated with Borrelia burgdorferi Sensu Lato- or Anaplasma phagocytophilum-Infected Ixodes ricinus Ticks from Northwest Norway. Int J Microbiol 2013; 2013:805456. [PMID: 24282414 PMCID: PMC3826297 DOI: 10.1155/2013/805456] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Revised: 08/16/2013] [Accepted: 09/11/2013] [Indexed: 11/18/2022] Open
Abstract
Ticks acquire a wide range of microorganisms as a natural part of their lifecycle. Bacteria, viruses, and protozoa can be transmitted to ticks during feeding and free-living phases. DGGE profiling is a molecular method to describe the microbial population associated with ticks and demonstrate some of the complexity and variety of tick-borne microorganisms. The present study profiled a total of 120 I. ricinus ticks, which were divided into three equally sized groups. We found that B. burgdorferi s.l.-infected ticks presented a pattern consisting of bacterial Pseudomonas spp. (67.5%), Bacillus spp. (50%), and Sphingomonas spp. (77.5%), while A. phagocytophilum-infected ticks were associated with Pseudomonas spp. (82.5%) and Sphingomonas spp. (57.5%). All profiles had one or more Pseudomonas species present, and the intramitochondrial endosymbiont Candidatus Midichloria mitochondrii was present in more than 25% of the samples. Statistical analysis demonstrated that the microbial communities were not significantly different between the groups and that the groups could not be characterised by a specific microbial population.
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Tveten AK. Prevalence of Borrelia burgdorferi sensu stricto, Borrelia afzelii, Borrelia garinii, and Borrelia valaisiana in Ixodes ricinus ticks from the northwest of Norway. ACTA ACUST UNITED AC 2013; 45:681-7. [DOI: 10.3109/00365548.2013.799288] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Serotype analysis of Streptococcus pneumoniae in lung and nasopharyngeal aspirates from children in the Gambia by MassTag PCR. J Clin Microbiol 2012; 51:995-7. [PMID: 23254132 DOI: 10.1128/jcm.02974-12] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Streptococcus pneumoniae strains comprise >90 serotypes. Here we describe establishment of a MassTag PCR assay designed to serotype S. pneumoniae and demonstrate its utility in tests using 31 paired lung aspirate and nasopharyngeal aspirate samples from children with pneumonia in the Gambia. Serotypes 1, 5, and 14 in were implicated in 90% of lung infections. With 5 exceptions, serotypes found in lung aspirates were also found in nasopharyngeal aspirates.
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Doellinger J, Schroeder K, Witt N, Heunemann C, Nitsche A. Comparison of real-time PCR and MassTag PCR for the multiplex detection of highly pathogenic agents. Mol Cell Probes 2012; 26:177-81. [PMID: 22819946 DOI: 10.1016/j.mcp.2012.07.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2012] [Revised: 06/06/2012] [Accepted: 07/10/2012] [Indexed: 11/30/2022]
Abstract
Multiplex PCR assays are a cost- as well as labour-effective way to analyse one sample for several pathogens simultaneously. Besides the mutual competition of the individual PCR reactions included in a multiplex PCR assay, their specific read-out displays a limiting factor for the total number of PCR reactions that can be multiplexed. In this study, two PCR systems with different read-out approaches are compared, using a pentaplex PCR assay for the detection of highly pathogenic agents. A pentaplex assay was used since five represents the current limit of real-time PCR multiplexing capacity due to the low resolution of fluorescence emission peaks of the current equipment. In contrast, MassTag PCR as a quite new technique offers the possibility to detect up to 20-30 target sequences from one reaction. After extensive and separate optimisation of the PCR protocol for both platforms, a comparative probit analysis showed good sensitivities for MassTag and real-time PCR detection. Nevertheless, the detection limits of MassTag PCR have been undercut by the real-time PCR for each target. We therefore conclude that MassTag PCR is a useful diagnostic technique for the sensitive screening for pathogens by highly multiplexed PCR assays, but cannot reach the sensitivity of real-time PCR for lower multiplexed PCR assays.
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Affiliation(s)
- Joerg Doellinger
- Centre for Biological Security, Robert Koch Institute, Berlin, Germany.
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Multiplex PCR Product Detection and Discrimination. Mol Microbiol 2011. [DOI: 10.1128/9781555816834.ch21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Abstract
Recent advances in nucleic acid diagnostic technologies have revolutionized microbiology by facilitating rapid, sensitive pathogen surveillance and differential diagnosis of infectious diseases. With the expansion and dissemination of genomic sequencing technology scientists are discovering new microbes at an accelerating pace. In this article we review recent progress in the field of pathogen surveillance and discovery with a specific focus on applications in the field of laboratory animal research. We discuss the challenges in proving a causal relationship between the presence of a candidate organism and disease. We also discuss the strengths and limitations of various assay platforms and describe a staged strategy for viral diagnostics. To illustrate the complexity of pursuing pathogen discovery research, we include examples from our own work that are intended to provide insights into the process that led to the selection of particular strategies.
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Affiliation(s)
- Gustavo Palacio
- Mailman School of Public Health, Columbia University, New York, NY 10032, USA.
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Tokarz R, Jain K, Bennett A, Briese T, Lipkin WI. Assessment of polymicrobial infections in ticks in New York state. Vector Borne Zoonotic Dis 2010; 10:217-21. [PMID: 19725770 DOI: 10.1089/vbz.2009.0036] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
Ixodes scapularis ticks are clinically important hematophagous vectors. A single tick bite can lead to a polymicrobial infection. We determined the prevalence of polymicrobial infection with Borrelia burgdorferi, Anaplasma phagocytophilum, Babesia microti, Borrelia miyamotoi, and Powassan virus in 286 adult ticks from the two counties in New York State where Lyme disease is endemic, utilizing a MassTag multiplex polymerase chain reaction assay. Seventy-one percent of the ticks harbored at least one organism; 30% had a polymicrobial infection. Infections with three microbes were detected in 5% of the ticks. One tick was infected with four organisms. Our results show that coinfection is a frequent occurrence in ticks in the two counties surveyed.
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Affiliation(s)
- Rafal Tokarz
- Center for Infection and Immunity, Mailman School of Public Health, Columbia University, New York, New York 10032, USA
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Abstract
The rate of discovery of new microbes and of new associations of microbes with health and disease is accelerating. Many factors contribute to this phenomenon including those that favor the true emergence of new pathogens as well as new technologies and paradigms that enable their detection and characterization. This chapter reviews recent progress in the field of pathogen surveillance and discovery with a focus on viral hemorrhagic fevers.
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Affiliation(s)
- W Ian Lipkin
- Center for Infection and Immunity, Mailman School of Public Health of Columbia University, New York, New York, USA.
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