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Rolfe RJ, Sheldon SW, Kingry LC, Petersen JM, Maro VP, Kinabo GD, Saganda W, Maze MJ, Halliday JEB, Nicholson WL, Galloway RL, Rubach MP, Crump JA. Metagenomic Detection of Bacterial Zoonotic Pathogens among Febrile Patients, Tanzania, 2007-2009 1. Emerg Infect Dis 2024; 30:1599-1608. [PMID: 39043406 PMCID: PMC11286057 DOI: 10.3201/eid3008.240529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/25/2024] Open
Abstract
Bacterial zoonoses are established causes of severe febrile illness in East Africa. Within a fever etiology study, we applied a high-throughput 16S rRNA metagenomic assay validated for detecting bacterial zoonotic pathogens. We enrolled febrile patients admitted to 2 referral hospitals in Moshi, Tanzania, during September 2007-April 2009. Among 788 participants, median age was 20 (interquartile range 2-38) years. We performed PCR amplification of V1-V2 variable region 16S rRNA on cell pellet DNA, then metagenomic deep-sequencing and pathogenic taxonomic identification. We detected bacterial zoonotic pathogens in 10 (1.3%) samples: 3 with Rickettsia typhi, 1 R. conorii, 2 Bartonella quintana, 2 pathogenic Leptospira spp., and 1 Coxiella burnetii. One other sample had reads matching a Neoerhlichia spp. previously identified in a patient from South Africa. Our findings indicate that targeted 16S metagenomics can identify bacterial zoonotic pathogens causing severe febrile illness in humans, including potential novel agents.
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Nasirian H. Hard Tick Species Parasitism Levels in Domestic Ruminants with Their Distribution and Role as Vectors: A Detailed Global Meta-analysis and Systematic Review. Acta Parasitol 2024; 69:1-105. [PMID: 37987883 DOI: 10.1007/s11686-023-00724-8] [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: 05/21/2022] [Accepted: 10/03/2023] [Indexed: 11/22/2023]
Abstract
PURPOSE This comprehensive global meta-analysis reviews the parasitism levels of tick genera and species, life stages, seasonality, attachment sites, the global mean ranks of tick species parasitism rates and records, and their distribution and role as vectors. METHODS From the 418 papers identified, 390 papers were selected to become part of the study. RESULTS The genera recorded as infesting domestic ruminants were Rhipicephalus (42 species), Haemaphysalis (32 species), Hyalomma (19 species), Amblyomma (18 species), Ixodes (10 species), Dermacentor (8 species), Margaropus and Nosomma (1 species). Globally, domestic ruminants are more infested by adult females and males than by the nymphal and larval stages of the tick species. The global tick species parasitism levels at the attachment sites of domestic ruminants were, in order, tail and anal region, neck and dewlap, scrotum or udder, ear region, thigh and abdomen, and dorsal surface. CONCLUSIONS Among 131 species of eight genera of hard ticks recorded infesting domestic ruminants, 42 species had mean ranks of tick species parasitism rates up to 10%, and 37 species had mean ranks of tick species parasitism up to 10 records. Briefly, the higher the indexes of tick species parasitism rates and records, the more important their role as vectors. In addition, the majority of them are found among tick species-infested humans with nearly high ranks of tick species parasitism rates and records that double their medical, veterinary, and zoonotic importance to be the most common vectors and reservoirs of bacterial, protozoan, and viral pathogenic microorganisms, causing severe infectious diseases, and as a result, can be more dangerous to humans and domestic ruminants.
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Affiliation(s)
- Hassan Nasirian
- Department of Medical Entomology and Vector Control, School of Public Health, Tehran University of Medical Sciences, Tehran, Islamic Republic of Iran.
- Institute for Environmental Research (IER), Tehran University of Medical Sciences, Tehran, Islamic Republic of Iran.
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Lilak AA, Pecor DB, Matulis G, Potter AM, Wofford RN, Kearney MF, Mitchell S, Jaradat F, Kano A, Zimmerman DM, Hassell JM, Kumsa B, Kamau M, Linton YM, von Fricken ME. Data release: targeted systematic literature search for tick and tick-borne pathogen distributions in six countries in sub-Saharan Africa from 1901 to 2020. Parasit Vectors 2024; 17:84. [PMID: 38389097 PMCID: PMC10885379 DOI: 10.1186/s13071-023-06086-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Accepted: 12/07/2023] [Indexed: 02/24/2024] Open
Abstract
BACKGROUND Surveillance data documenting tick and tick-borne disease (TBD) prevalence is needed to develop risk assessments and implement control strategies. Despite extensive research in Africa, there is no standardized, comprehensive review. METHODS Here we tackle this knowledge gap, by producing a comprehensive review of research articles on ticks and TBD between 1901 and 2020 in Chad, Djibouti, Ethiopia, Kenya, Tanzania, and Uganda. Over 8356 English language articles were recovered. Our search strategy included 19 related MeSH terms. Articles were reviewed, and 331 met inclusion criteria. Articles containing mappable data were compiled into a standardized data schema, georeferenced, and uploaded to VectorMap. RESULTS Tick and pathogen matrixes were created, providing information on vector distributions and tick-pathogen associations within the six selected African countries. CONCLUSIONS These results provide a digital, mappable database of current and historical tick and TBD distributions across six countries in Africa, which can inform specific risk modeling, determine surveillance gaps, and guide future surveillance priorities.
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Affiliation(s)
- Abigail A Lilak
- One Health Center of Excellence, Emerging Pathogens Institute, University of Florida, 2055 Mowry Road, Gainesville, FL, 32611, USA
- Department of Environmental & Global Health, University of Florida, Gainesville, FL, USA
| | - David B Pecor
- Walter Reed Biosystematics Unit (WRBU), Smithsonian Museum Support Center, Suitland, MD, USA
- Department of Entomology, Smithsonian Institution-National Museum of Natural History, Washington, DC, USA
- One Health Branch, Walter Reed Army Institute of Research (WRAIR), Silver Spring, Maryland, USA
| | - Graham Matulis
- One Health Center of Excellence, Emerging Pathogens Institute, University of Florida, 2055 Mowry Road, Gainesville, FL, 32611, USA
- Department of Environmental & Global Health, University of Florida, Gainesville, FL, USA
| | - Alexander M Potter
- Walter Reed Biosystematics Unit (WRBU), Smithsonian Museum Support Center, Suitland, MD, USA
- Department of Entomology, Smithsonian Institution-National Museum of Natural History, Washington, DC, USA
- One Health Branch, Walter Reed Army Institute of Research (WRAIR), Silver Spring, Maryland, USA
| | | | | | - Stephanie Mitchell
- Walter Reed Biosystematics Unit (WRBU), Smithsonian Museum Support Center, Suitland, MD, USA
| | | | - Arisa Kano
- George Mason University, Fairfax, VA, USA
| | - Dawn M Zimmerman
- Department of Entomology, Smithsonian Institution-National Museum of Natural History, Washington, DC, USA
- Yale University, New Haven, CT, USA
| | - James M Hassell
- Department of Entomology, Smithsonian Institution-National Museum of Natural History, Washington, DC, USA
- Yale University, New Haven, CT, USA
| | - Bersissa Kumsa
- Department of Pathology & Parasitology, College of Veterinary Medicine and Agriculture, Addis Ababa University, Bishoftu, Ethiopia
| | - Maureen Kamau
- Walter Reed Biosystematics Unit (WRBU), Smithsonian Museum Support Center, Suitland, MD, USA
- Mpala Research Center, Nanyuki, Kenya
| | - Yvonne-Marie Linton
- Walter Reed Biosystematics Unit (WRBU), Smithsonian Museum Support Center, Suitland, MD, USA
- Department of Entomology, Smithsonian Institution-National Museum of Natural History, Washington, DC, USA
- One Health Branch, Walter Reed Army Institute of Research (WRAIR), Silver Spring, Maryland, USA
| | - Michael E von Fricken
- One Health Center of Excellence, Emerging Pathogens Institute, University of Florida, 2055 Mowry Road, Gainesville, FL, 32611, USA.
- Department of Environmental & Global Health, University of Florida, Gainesville, FL, USA.
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Magesa WS, Haji I, Kinimi E, Nzalawahe JS, Kazwala R. Distribution and molecular identification of ixodid ticks infesting cattle in Kilombero and Iringa Districts, Tanzania. BMC Vet Res 2023; 19:121. [PMID: 37573333 PMCID: PMC10422822 DOI: 10.1186/s12917-023-03652-x] [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: 08/27/2022] [Accepted: 07/14/2023] [Indexed: 08/14/2023] Open
Abstract
BACKGROUND Hard ticks infesting cattle are vectors of Tick-borne diseases that causes major public health problems and considerable socioeconomic losses to the livestock industry in tropical and subtropical countries. A repeated cross-sectional study was carried out by collecting ticks on cattle during the wet and dry seasons from January to August 2021 in order to determine hard tick prevalence, distribution, and abundance on cattle in Kilombero and Iringa Districts of Tanzania. The collected ticks were identified morphologically using published morphological keys under a stereomicroscope and confirmed by polymerase chain reaction (PCR) and sequencing. RESULTS Out of 740 examined cattle, 304, (41.08%) were infested with ticks. In total, 1,780 ticks were counted on one side of the animal's body and doubled, whereby resulting in a total of 3,560 ticks were recorded. Individual tick burden ranged from n = 2 to 82 ticks per animal, with a mean tick burden of n = 11.7 ± 0.68 per animal. A total of 1,889 ticks were collected from infected cattle including 109 additional ticks observed while collecting ticks based on the animal's posture when restrained to the ground. Out of 1,889 ticks, nine species from three genera were identified morphologically: 1,377 fit in the genus Rhipicephalus, 459 to the genus of Amblyomma, and 53 to the genus Hyalomma. Rhipicephalus microplus was the most prevalent (n = 909, 48.1%), followed by Rhipicephalus evertsi (n = 310, 16.4%), Amblyomma lepidum (n = 310, 16.4%), Rhipicephalus appendiculatus (n = 140, 7.4%), Amblyomma gemma (n = 120, 6.4%), Hyalomma rufipes (n = 50, 2.6%), Amblyomma variegatum (n = 29, 1.5%), Rhipicephalus decoloratus (n = 18, 1.0%), while the least common was Hyalomma albiparmatum (n = 3, 0.2%). Tick diversity was higher in Iringa compared to Kilombero District. Tick prevalence was higher in wet season (n = 148, 41.11%). Ticks were widely distributed in different parts of the host body, with the highest distribution on zone 4 (n = 1,060, 56.11%), which includes groin, flank, abdomen, and around inner thigh of the hind legs and the lowest distribution on zone 2 (n = 14, 0.74%), which includes the back surface of the body. Both Amblyomma lepidum and Rhipicephalus microplus species were found in all the five body zones, and with the highest proportions recorded on zone 4: A. lepidum (n = 209, 67.42%) and R. microplus (n = 714, 78.55%). The nine tick species identified morphologically were also confirmed using molecular methods. However, during sequencing, two species (Rhipicephalus appendiculatus and R. decoloratus) had poor quality sequences and were excluded from the sequence analysis. Sequencing results indicated high nucleotide identity (96-100%) with sequences available in GenBank and Barcode of Life Database (BOLD). The phylogenetic analysis of partial mitochondrial COI and 16S rRNA gene sequences of ticks were used to confirm the morphological identification. CONCLUSION The results showed a high burden of tick infestation on cattle, which could reduce animal production and potentially increase the risk of tick-borne diseases. Therefore, it is necessary to explore the epidemiological and molecular aspects of various tick species in other regions of Tanzania.
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Affiliation(s)
- Walter S Magesa
- Department of Veterinary Microbiology, Parasitology and Biotechnology, Sokoine University of Agriculture, P.O. Box 3019, Morogoro, Tanzania.
| | - Isihaka Haji
- Department of Veterinary Microbiology, Parasitology and Biotechnology, Sokoine University of Agriculture, P.O. Box 3019, Morogoro, Tanzania
| | - Edson Kinimi
- Department of Veterinary Physiology, Biochemistry and Pharmacology, Sokoine University of Agriculture, P.O. Box 3017, Morogoro, Tanzania
| | - Jahashi S Nzalawahe
- Department of Veterinary Microbiology, Parasitology and Biotechnology, Sokoine University of Agriculture, P.O. Box 3019, Morogoro, Tanzania
| | - Rudovick Kazwala
- Department of Veterinary Medicine and Public Health, Sokoine University of Agriculture, P.O. Box 3021, Morogoro, Tanzania
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Haji I, Simuunza M, Jiang N, Chen Q. Tick populations and molecular detection of selected tick-borne pathogens in questing ticks from northern and central Tanzania. EXPERIMENTAL & APPLIED ACAROLOGY 2023; 90:389-407. [PMID: 37464132 PMCID: PMC10406711 DOI: 10.1007/s10493-023-00816-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Accepted: 06/22/2023] [Indexed: 07/20/2023]
Abstract
Ticks are vectors and reservoirs of a variety of pathogens including protozoa, bacteria and viruses which cause tick-borne diseases (TBDs) in humans and livestock. TBDs pose serious constraints to the improvement of livestock production in tropical and subtropical regions of the world. Despite their wide distribution, information on the tick and pathogen relationship is scarce in Tanzania. We used nested PCR and sequencing to screen pathogens of public and veterinary health importance in ticks collected by flagging from four districts of Tanzania. In total, 2021 ticks comprising nine species were identified. DNA from ticks was pooled according to tick species, developmental stage, and location, then screened for Babesia bigemina, Babesia bovis, Theileria parva and Coxiella burnetii. Out of 377 pools, 34.7% were positive for at least one pathogen. Theileria parva was the most abundant with a minimum infection rate (MIR) of 2.8%, followed by B. bigemina (MIR = 1.8%) and B. bovis (MIR = 0.8%). Multiple pathogens detection was observed in 7.2% of the tested pools. However, PCR screening of individual tick DNA revealed that only 0.3% of the examined pools had co-infection. DNA of C. burnetii was never detected in any tick DNA pool. The MIR of tick-borne pathogens (TBPs) differed significantly among districts, seasons, tick species, and tick developmental stages. Sequence analysis showed that B. bigemina RAP-1a, B. bovis SBP-4, and T. parva p104 genes were conserved among pathogens in the four districts. Despite the absence of C. burnetii in ticks, considering its pathogenic potential, it is essential to continue monitoring for its possible recurrence in ticks. This information adds to the knowledge of TBPs epidemiology and will contribute to the scientific basis for planning future control strategies.
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Affiliation(s)
- Isihaka Haji
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Key Laboratory of Zoonosis, Ministry of Education, Shenyang Agricultural University, Shenyang, 110866, China.
- Department of Veterinary Microbiology, Parasitology and Biotechnology, Sokoine University of Agriculture, P. O. Box 3019, Morogoro, Tanzania.
| | - Martin Simuunza
- Department of Disease Control, School of Veterinary Medicine, University of Zambia, P. O. Box 32379, Lusaka, Zambia
- Africa Centre of Excellence for Infectious Diseases of Humans and Animals, University of Zambia, P. O. Box 32379, Lusaka, Zambia
| | - Ning Jiang
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Key Laboratory of Zoonosis, Ministry of Education, Shenyang Agricultural University, Shenyang, 110866, China
- Research Unit for Pathogenic Mechanisms of Zoonotic Parasites, Chinese Academy of Medical Sciences, 120 Dongling Road, Shenyang, 110866, China
| | - Qijun Chen
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Key Laboratory of Zoonosis, Ministry of Education, Shenyang Agricultural University, Shenyang, 110866, China.
- Research Unit for Pathogenic Mechanisms of Zoonotic Parasites, Chinese Academy of Medical Sciences, 120 Dongling Road, Shenyang, 110866, China.
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Ringo AE, Nonga HE, Galon EM, Ji S, Rizk MA, El-Sayed SAES, Mohanta UK, Ma Z, Chikufenji B, Do TT, Xuan X. Molecular Investigation of Tick-Borne Haemoparasites Isolated from Indigenous Zebu Cattle in the Tanga Region, Tanzania. Animals (Basel) 2022; 12:ani12223171. [PMID: 36428398 PMCID: PMC9686548 DOI: 10.3390/ani12223171] [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: 09/30/2022] [Revised: 11/09/2022] [Accepted: 11/14/2022] [Indexed: 11/18/2022] Open
Abstract
Tick-borne diseases (TBDs) are a major hindrance to livestock production in pastoral communities of Africa. Although information on tick-borne infections is necessary for setting up control measures, this information is limited in the pastoral communities of Tanzania. Therefore, this study aimed to provide an overview of the tick-borne infections in the indigenous cattle of Tanzania. A total of 250 blood samples were collected from the indigenous zebu cattle in the Tanga region, Tanzania. Then, we conducted a molecular survey using the polymerase chain reaction (PCR) and gene sequencing to detect and identify the selected tick-borne pathogens. The PCR was conducted using assays, based on Theileria spp. (18S rRNA), Theileria parva (p104), Theileria mutans and T. taurotragi (V4 region of the 18S rRNA), Babesia bigemina (RAP-1a), B. bovis (SBP-2), Anaplasma marginale (heat shock protein groEL) and Ehrlichia ruminantium (pCS20). The PCR screening revealed an overall infection rate of (120/250, 48%) for T. mutans, (64/250, 25.6%) for T. parva, (52/250, 20.8%) for T. taurotragi, (33/250, 13.2%) for B. bigemina and (81/250, 32.4%) for A. marginale. Co-infections of up to four pathogens were revealed in 44.8% of the cattle samples. A sequence analysis indicated that T. parva p104 and A. marginale groEL genes were conserved among the sampled animals with sequence identity values of 98.92−100% and 99.88−100%, respectively. Moreover, the B. bigemina RAP-1a gene and the V4 region of the 18S rRNA of T. mutans genes were diverse among the sampled cattle, indicating the sequence identity values of 99.27−100% and 22.45−60.77%, respectively. The phylogenetic analyses revealed that the T. parva (p104) and A. marginale (groEL) gene sequences of this study were clustered in the same clade. In contrast, the B. bigemina (RAP-1a) and the T. mutans V4 region of the 18S rRNA gene sequences appeared in the different clades. This study provides important basement data for understanding the epidemiology of tick-borne diseases and will serve as a scientific basis for planning future control strategies in the study area.
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Affiliation(s)
- Aaron Edmond Ringo
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro 080-8555, Hokkaido, Japan
- Zanzibar Livestock Research Institute, Ministry of Agriculture, Irrigation, Natural Resources and Livestock, Zanzibar P.O. Box 159, Tanzania
| | - Hezron Emanuel Nonga
- Ministry of Livestock and Fisheries, Government City Mtumba, Dodoma P.O. Box 2870, Tanzania
| | - Eloiza May Galon
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro 080-8555, Hokkaido, Japan
| | - Shengwei Ji
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro 080-8555, Hokkaido, Japan
| | - Mohamed Abdo Rizk
- Department of Internal medicine and Infectious Diseases, Faculty of Veterinary Medicine, Mansoura University, Mansoura 35516, Egypt
| | - Shimaa Abd El-Salam El-Sayed
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro 080-8555, Hokkaido, Japan
- Department of Biochemistry and Chemistry of Nutrition, Faculty of Veterinary Medicine, Mansoura 35516, Egypt
| | - Uday Kumar Mohanta
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro 080-8555, Hokkaido, Japan
| | - Zhuowei Ma
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro 080-8555, Hokkaido, Japan
| | - Boniface Chikufenji
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro 080-8555, Hokkaido, Japan
| | - Thanh Thom Do
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro 080-8555, Hokkaido, Japan
| | - Xuenan Xuan
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro 080-8555, Hokkaido, Japan
- Correspondence: ; Tel.: +81-(155)-495-648
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Haji I, Simuunza M, Kerario II, Jiang N, Chen Q. Epidemiology of tick-borne pathogens of cattle and tick control practices among mixed farming and pastoral communities in Gairo and Monduli districts, Tanzania. Vet Parasitol Reg Stud Reports 2022; 32:100738. [PMID: 35725102 DOI: 10.1016/j.vprsr.2022.100738] [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: 07/30/2021] [Revised: 04/28/2022] [Accepted: 04/30/2022] [Indexed: 06/15/2023]
Abstract
Tick-borne diseases including East Coast fever, anaplasmosis and babesiosis constitute a major constraint to improving livestock production worldwide, including Tanzania. Determination of the prevalence and factors associated with the occurrence of pathogens in cattle is important for informed decision making on the control and prevention of these diseases. However, little is known about the epidemiology of these pathogens in cattle in some regions of Tanzania. Therefore, this study aimed at establishing the prevalence of Anaplasma marginale, Babesia bigemina, Babesia bovis and Theileria parva in cattle, determine the risk factors associated with infection with these pathogens and also to assess tick control practices in Gairo and Monduli districts of Tanzania. Out of the 520 cattle sampled, the majority (82.9%) were infested with ticks of different species, predominated by Rhipicephalus decoloratus (42.7%), Amblyomma variegatum (31.3%), Rhipicephalus pulchellus (23.1%) and Rhipicephalus appendiculatus (17.7%). Other ticks that were found on cattle included Rhipicephalus microplus (15.8%), Amblyomma gema (13.8%), Rhipicephalus evertsi (12.9%), Amblyomma lepidum (8.1%), Hyalomma truncatum (2.9%) and Hyalomma albiparmatum (2.1%). On microscopy 23 (4.4%) of 520 cattle were positive for hemoparasites. Of the 23 positive cattle, 13 (2.5%), 6 (1.2%) and 3 (0.6%) were monolithically infected with A. marginale, T. parva, and B. bovis respectively, while one (0.2% %) had co-infections of T. parva and A. marginale. The number of positive cattle increased to 184 (35.4%), when they were subjected to detection with PCR. This included the 23 samples that were positive on microscopy. Based on PCR, the overall prevalence of the pathogens from the two districts was 11.5%, 11.2%, 6.2% and 2.5% for B. bigemina, A. marginale, T. parva and B. bovis, respectively. Hemoparasite co-infection occurred in 6.9% of the cattle examined. The prevalence of co-infections was 2.7%, 4%, and 0.02% for T. parva/A. marginale, B. bigemina/A. marginale and B. bigemina/A. marginale/T. parva, respectively. Cattle with co-infections had significantly lower (p < 0.005) mean packed cell volume as compared to cattle with mono-infections. The majority (96%) of cattle examined were subjected to different methods of tick control. A number of risk factors were shown to be associated with the occurrence of tick-borne pathogens in cattle. Higher prevalence of A. marginale may be due to its wide range of biological and mechanical transmission. These findings could be used to strengthen future control programs for ticks and tick-borne diseases in the study areas.
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Affiliation(s)
- Isihaka Haji
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, Shenyang Agricultural University, Shenyang 110866, China
| | - Martin Simuunza
- Department of Disease Control, School of Veterinary Medicine, University of Zambia, P. O. Box 32379, Lusaka, Zambia
| | - Isack Ibrahim Kerario
- Department of Animal, Aquaculture and Range Sciences, College of Agriculture, Sokoine University of Agriculture, P.O. Box 3004, Morogoro, Tanzania
| | - Ning Jiang
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, Shenyang Agricultural University, Shenyang 110866, China; Research Unit for Pathogenic Mechanisms of Zoonotic Parasites, Chinese Academy of Medical Sciences, 120 Dongling Road, Shenyang 110866, China
| | - Qijun Chen
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, Shenyang Agricultural University, Shenyang 110866, China; Research Unit for Pathogenic Mechanisms of Zoonotic Parasites, Chinese Academy of Medical Sciences, 120 Dongling Road, Shenyang 110866, China.
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Detailed new insights about tick infestations in domestic ruminant groups: a global systematic review and meta-analysis. J Parasit Dis 2022; 46:526-601. [DOI: 10.1007/s12639-021-01460-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 11/21/2021] [Indexed: 01/09/2023] Open
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9
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Allan FK, Sindoya E, Adam KE, Byamungu M, Lea RS, Lord JS, Mbata G, Paxton E, Mramba F, Torr SJ, Morrison WI, Handel I, Morrison LJ, Auty HK. A cross-sectional survey to establish Theileria parva prevalence and vector control at the wildlife-livestock interface, Northern Tanzania. Prev Vet Med 2021; 196:105491. [PMID: 34562810 PMCID: PMC8573586 DOI: 10.1016/j.prevetmed.2021.105491] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 09/02/2021] [Accepted: 09/09/2021] [Indexed: 11/28/2022]
Abstract
East Coast fever (ECF) in cattle is caused by the protozoan parasite Theileria parva, transmitted by Rhipicephalus appendiculatus ticks. In cattle ECF is often fatal, causing annual losses >$500 million across its range. The African buffalo (Syncerus caffer) is the natural host for T. parva but the transmission dynamics between wild hosts and livestock are poorly understood. This study aimed to determine the prevalence of T. parva in cattle, in a 30 km zone adjacent to the Serengeti National Park, Tanzania where livestock and buffalo co-exist, and to ascertain how livestock keepers controlled ECF and other vector-borne diseases of cattle. A randomised cross-sectional cattle survey and questionnaire of vector control practices were conducted. Blood samples were collected from 770 cattle from 48 herds and analysed by PCR to establish T. parva prevalence. Half body tick counts were recorded on every animal. Farmers were interviewed (n = 120; including the blood sampled herds) using a standardised questionnaire to obtain data on vector control practices. Local workshops were held to discuss findings and validate results. Overall prevalence of T. parva in cattle was 5.07% (CI: 3.70-7.00%), with significantly higher prevalence in older animals. Although all farmers reported seeing ticks on their cattle, tick counts were very low with 78% cattle having none. Questionnaire analysis indicated significant acaricide use with 79% and 41% of farmers reporting spraying or dipping with cypermethrin-based insecticides, respectively. Some farmers reported very frequent spraying, as often as every four days. However, doses per animal were often insufficient. These data indicate high levels of acaricide use, which may be responsible for the low observed tick burdens and low ECF prevalence. This vector control is farmer-led and aimed at both tick- and tsetse-borne diseases of livestock. The levels of acaricide use raise concerns regarding sustainability; resistance development is a risk, particularly in ticks. Integrating vaccination as part of this community-based disease control may alleviate acaricide dependence, but increased understanding of the Theileria strains circulating in wildlife-livestock interface areas is required to establish the potential benefits of vaccination.
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Affiliation(s)
- Fiona K Allan
- Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, EH25 9RG, United Kingdom.
| | - Emmanuel Sindoya
- Minstry of Livestock and Fisheries, Serengeti District Livestock Office, Mugumu, Tanzania
| | - Katherine E Adam
- Innogen Institute, Science Technology and Innovation Studies; School of Social and Political Science, University of Edinburgh, Old Surgeons' Hall, High School Yards, Edinburgh, United Kingdom
| | | | - Rachel S Lea
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Jennifer S Lord
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Geofrey Mbata
- Vector and Vector-borne Diseases Research Institute, Tanga, Tanzania
| | - Edith Paxton
- Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, EH25 9RG, United Kingdom
| | - Furaha Mramba
- Tanzania Veterinary Laboratory Agency, Dar es Salaam, Tanzania
| | - Stephen J Torr
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - W Ivan Morrison
- Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, EH25 9RG, United Kingdom
| | - Ian Handel
- Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, EH25 9RG, United Kingdom
| | - Liam J Morrison
- Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, EH25 9RG, United Kingdom
| | - Harriet K Auty
- Institute of Biodiversity, Animal Health & Comparative Medicine, College of Medical, Veterinary & Life Sciences, University of Glasgow, United Kingdom (Previously Epidemiology Research Unit, SRUC, Inverness, United Kingdom)
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10
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Models for Studying the Distribution of Ticks and Tick-Borne Diseases in Animals: A Systematic Review and a Meta-Analysis with a Focus on Africa. Pathogens 2021; 10:pathogens10070893. [PMID: 34358043 PMCID: PMC8308717 DOI: 10.3390/pathogens10070893] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2021] [Revised: 06/30/2021] [Accepted: 07/12/2021] [Indexed: 11/17/2022] Open
Abstract
Ticks and tick-borne diseases (TTBD) are constraints to the development of livestock and induce potential human health problems. The worldwide distribution of ticks is not homogenous. Some places are ecologically suitable for ticks but they are not introduced in these areas yet. The absence or low density of hosts is a factor affecting the dissemination of the parasite. To understand the process of introduction and spread of TTBD in different areas, and forecast their presence, scientists developed different models (e.g., predictive models and explicative models). This study aimed to identify models developed by researchers to analyze the TTBD distribution and to assess the performance of these various models with a meta-analysis. A literature search was implemented with PRISMA protocol in two online databases (Scopus and PubMed). The selected articles were classified according to country, type of models and the objective of the modeling. Sensitivity, specificity and accuracy available data of these models were used to evaluate their performance using a meta-analysis. One hundred studies were identified in which seven tick genera were modeled, with Ixodes the most frequently modeled. Additionally, 13 genera of tick-borne pathogens were also modeled, with Borrelia the most frequently modeled. Twenty-three different models were identified and the most frequently used are the generalized linear model representing 26.67% and the maximum entropy model representing 24.17%. A focus on TTBD modeling in Africa showed that, respectively, genus Rhipicephalus and Theileria parva were the most modeled. A meta-analysis on the quality of 20 models revealed that maximum entropy, linear discriminant analysis, and the ecological niche factor analysis models had, respectively, the highest sensitivity, specificity, and area under the curve effect size among all the selected models. Modeling TTBD is highly relevant for predicting their distribution and preventing their adverse effect on animal and human health and the economy. Related results of such analyses are useful to build prevention and/or control programs by veterinary and public health authorities.
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11
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Pollicino LC, Masetti M, Stevenazzi S, Cristaldi A, Righetti C, Gorla M. Multi-aquifer susceptibility analyses for supporting groundwater management in urban areas. JOURNAL OF CONTAMINANT HYDROLOGY 2021; 238:103774. [PMID: 33626464 DOI: 10.1016/j.jconhyd.2021.103774] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 09/17/2020] [Accepted: 01/17/2021] [Indexed: 06/12/2023]
Abstract
In the densely urbanised Milan Metropolitan area (northern Italy), the long history of anthropogenic activities still exerts a significant pressure on groundwater resource. One of the most serious threats to the water quality of urban aquifers is attributed to diffuse contamination, which is caused by a series of unknown small sources (i.e., multiple point sources) distributed over large areas. In the study area and in many industrialised regions of the world, tetrachloroethylene [PCE], trichloroethylene [TCE] and hexavalent chromium [Cr(VI)] represent the common example of long-standing and persistent pollution in groundwater. In the Milan Metropolitan area, high levels of PCE + TCE and Cr(VI) were detected in the shallow aquifer as well as in the deep aquifer. To assess and map the shallow and deep aquifers susceptibility to PCE + TCE and Cr(VI) contamination at a regional scale, the Weights of Evidence modelling technique has been applied. This method has been used to objectively evaluate the spatial correlation between the high presence of these pollutants in each aquifer and hydrogeological and land use factors that can potentially influence the contamination. Moreover, the results allowed us to quantify on a large scale the effect that preferential flowpaths, due to both thickness variation in the aquitard and the areal density of multi aquifer wells, have in reducing the protection of the underlying deep aquifer. The end-products of the study constitute a key tool to be used by water-resource managers and decision-makers for the improvement of groundwater management and protection strategies.
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Affiliation(s)
- Licia C Pollicino
- Dipartimento di Scienze della Terra "A. Desio", Università degli Studi di Milano, 20133 Milan, Italy; Dipartimento di Ingegneria Civile e Ambientale (DICA), Politecnico di Milano, 20133 Milan, Italy
| | - Marco Masetti
- Dipartimento di Scienze della Terra "A. Desio", Università degli Studi di Milano, 20133 Milan, Italy
| | - Stefania Stevenazzi
- Dipartimento di Scienze della Terra "A. Desio", Università degli Studi di Milano, 20133 Milan, Italy.
| | - Agata Cristaldi
- Gruppo CAP, Ufficio Progetto PIA e Bonifiche - Direzione Ricerca e Sviluppo, Milan, Italy
| | - Chiara Righetti
- Gruppo CAP, Ufficio Progetto PIA e Bonifiche - Direzione Ricerca e Sviluppo, Milan, Italy
| | - Maurizio Gorla
- Gruppo CAP, Ufficio Progetto PIA e Bonifiche - Direzione Ricerca e Sviluppo, Milan, Italy
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12
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Lippi CA, Gaff HD, White AL, Ryan SJ. Scoping review of distribution models for selected Amblyomma ticks and rickettsial group pathogens. PeerJ 2021; 9:e10596. [PMID: 33643699 PMCID: PMC7896504 DOI: 10.7717/peerj.10596] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 11/26/2020] [Indexed: 01/23/2023] Open
Abstract
The rising prevalence of tick-borne diseases in humans in recent decades has called attention to the need for more information on geographic risk for public health planning. Species distribution models (SDMs) are an increasingly utilized method of constructing potential geographic ranges. There are many knowledge gaps in our understanding of risk of exposure to tick-borne pathogens, particularly for those in the rickettsial group. Here, we conducted a systematic scoping review of the SDM literature for rickettsial pathogens and tick vectors in the genus Amblyomma. Of the 174 reviewed articles, only 24 studies used SDMs to estimate the potential extent of vector and/or pathogen ranges. The majority of studies (79%) estimated only tick distributions using vector presence as a proxy for pathogen exposure. Studies were conducted at different scales and across multiple continents. Few studies undertook original data collection, and SDMs were mostly built with presence-only datasets from public database or surveillance sources. The reliance on existing data sources, using ticks as a proxy for disease risk, may simply reflect a lag in new data acquisition and a thorough understanding of the tick-pathogen ecology involved.
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Affiliation(s)
- Catherine A. Lippi
- Department of Geography, University of Florida, Gainesville, FL, USA
- Emerging Pathogens Institute, University of Florida, Gainesville, FL, USA
| | - Holly D. Gaff
- Department of Biology, Old Dominion University, Norfolk, VA, USA
- School of Mathematics, Statistics and Computer Science, University of Kwa-Zulu Natal, Durban, South Africa
| | - Alexis L. White
- Department of Geography, University of Florida, Gainesville, FL, USA
- Emerging Pathogens Institute, University of Florida, Gainesville, FL, USA
| | - Sadie J. Ryan
- Department of Geography, University of Florida, Gainesville, FL, USA
- Emerging Pathogens Institute, University of Florida, Gainesville, FL, USA
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13
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Damian D, Damas M, Wensman JJ, Berg M. Genetic Relationship Between Hard Ticks ( Ixodidae) Infesting Cattle from Select Areas of a Wildlife-Livestock Interface Ecosystem at Mikumi National Park, Tanzania. Vector Borne Zoonotic Dis 2021; 21:191-199. [PMID: 33450167 DOI: 10.1089/vbz.2020.2706] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Background: There has recently been a substantial increase in the number of tick species and tick-borne infectious agents in Tanzania. Owing to their impact on human, livestock, and wild animal health, increased knowledge of ticks is needed. So far, no published data on the genetic relationship between hard tick (Ixodidae) sequences collected from cattle are available in Tanzania. Methods: Ticks from cattle in the wards, which lie at the border of Mikumi National Park, were collected in the dry season, November to December 2019. Morphological identification of ticks was initially performed at the genus level. To identify ticks at the species level, molecular analysis based on the 16S rRNA gene was performed. Evolutionary relationships and genetic distances between ticks were determined using MaximumLikelihood and Kimura 2-parameter methods, respectively. Results: Based on morphology, two genera (Rhipicephalus and Hyalomma) were identified in the 630 adult ticks collected from a total of 252 cattle. Six species (Rhipicephalus microplus, Rhipicephalus evertsi, Hyalomma marginatum, Hyalomma rufipes, Hyalomma truncatum, and Hyalomma turanicum) were confirmed by BLASTn and phylogenetic analyses. Considerable mean and pairwise genetic distances were observed for Rhipicephalus and Hyalomma genera. Conclusion: The presence of different phylogenetic clusters and considerable mean and pairwise genetic distances observed reflect possible biological diversity of hard ticks present in the study area. Considering the value of the cattle in the livelihoods and economies of people and the country, the outcomes of this study will be useful in planning integrated control strategies for ticks and tick-borne diseases in Tanzania.
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Affiliation(s)
- Donath Damian
- Department of Molecular Biology and Biotechnology, University of Dar es Salaam, Dar es Salaam, United Republic of Tanzania
| | - Modester Damas
- Department of Molecular Biology and Biotechnology, University of Dar es Salaam, Dar es Salaam, United Republic of Tanzania
| | - Jonas Johansson Wensman
- Section of Ruminant Medicine, Department of Clinical Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Mikael Berg
- Section of Virology, Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, Uppsala, Sweden
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14
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Pollicino LC, Colombo L, Alberti L, Masetti M. PCE point source apportionment using a GIS-based statistical technique combined with stochastic modelling. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 750:142366. [PMID: 33182200 DOI: 10.1016/j.scitotenv.2020.142366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 09/10/2020] [Accepted: 09/10/2020] [Indexed: 06/11/2023]
Abstract
To meet the continuous growth of urbanised areas with the ever-increasing demand for safe water supplies, the implementation of new scientifically based methodologies can represent a key support for preventing groundwater quality deterioration. In this study, a new combined approach based on the application of the Weights of Evidence and the Null-Space Monte Carlo particle back-tracking methods was set up to assess tetrachloroethylene (PCE) contamination due to Point Sources in the densely urbanised north-eastern sector of the Milano FUA (Functional Urban Area). This combined approach offers the advantage of further enhancing the power of each individual technique by integrating both the advective transport mechanism, neglected by the Weights of Evidence, and the influence of specific factors, such as the land use variation, not considered by the Null-Space Monte Carlo particle tracking. To accurately test and explore the performance of this new approach, the analysis was carried out based on the simulation of synthetic PCE plumes using a groundwater numerical model already implemented in a previous study. The Weights of Evidence method revealed that the areas characterised by a groundwater depth lower than 17 m, a groundwater velocity higher than 2.6 × 10-6 m/s, a recharge higher than 0.26 m/y and a significant variation of the industrial activities extent are the most susceptible to groundwater pollution. The Null-Space Monte Carlo particle back-tracking has proved to be effective in delineating the potential source zones and contaminant travel path. The proposed approach can offer additional insights for the protection of groundwater resource. The end-product provides crucial information on the zones that require to be prioritised for investigations and can be easily understood by non-expert decision-makers constituting an advanced tool for enhancing groundwater protection strategies.
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Affiliation(s)
- Licia C Pollicino
- Dipartimento di Ingegneria Civile e Ambientale (DICA), Politecnico di Milano, 20133 Milan, Italy
| | - Loris Colombo
- Dipartimento di Ingegneria Civile e Ambientale (DICA), Politecnico di Milano, 20133 Milan, Italy.
| | - Luca Alberti
- Dipartimento di Ingegneria Civile e Ambientale (DICA), Politecnico di Milano, 20133 Milan, Italy
| | - Marco Masetti
- Dipartimento di Scienze della Terra "A. Desio", Università degli Studi di Milano, 20133 Milan, Italy
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15
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Ringo AE, Rizk MA, Adjou Moumouni PF, Liu M, Galon EM, Li Y, Ji S, Tumwebaze M, Byamukama B, Thekisoe O, Xuan X. Molecular detection and characterization of tick-borne haemoparasites among cattle on Zanzibar Island, Tanzania. Acta Trop 2020; 211:105598. [PMID: 32592686 DOI: 10.1016/j.actatropica.2020.105598] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 06/22/2020] [Accepted: 06/23/2020] [Indexed: 11/27/2022]
Abstract
Tick-borne diseases (TBDs) are serious constraints to livestock production in Tanzania and other tropical and subtropical countries and impact the livelihoods of resource-poor farming communities in the region. In Tanzania, detailed studies on tick-borne pathogens (TBPs) in cattle using sensitive molecular detection methods are scarce. The objective of this study was to investigate the occurrence and species composition of bovine TBPs in cattle kept in Zanzibar Island. A total of 236 blood samples were randomly collected in cattle population in June and July 2019. We used polymerase chain reaction (PCR) and gene sequencing to detect and identify pathogens. PCR screening of all 236 samples revealed that 64.5% of animals were infected by TBPs, including Theileria parva (34.3%), T. mutans (38.1%), T. taurotragi (30.9%), Anaplasma marginale (10.2%), Babesia bigemina (5.1%), T. velifera (3.4%) and B. bovis (2.1%). Overall a total of 86 animals (36.4%) were co-infected with up to five pathogens including T. parva, T. mutans, T. taurotragi, A. marginale and B. bigemina. The pathogens mostly involved in the co-infection were T. parva, T. taurotragi and T. mutans. Sequence analysis indicated that T. parva p104 and B. bigemina RAP1a genes are diverse among the sampled animals in Zanzibar Island, with 99.64%-100% and 99.51%-100% nucleotide sequence identity value respectively. In contrast, the A. marginale MSP-5, T. mutans 18S rRNA V4 region and B. bovis SBP-2 genes are conserved, with 100%, 99.05%-100% and 99.66%-100% nucleotide sequence identity values respectively. The phylogenetic analyses revealed that T. parva p104 and B. bigemina RAP1a gene sequences showed significant differences of genotypes, as they appear in different clades. Meanwhile, A. marginale MSP-5, T. mutans 18S rRNA V4 region and B. bovis SBP-2 gene sequences appear in the same clade with other sequences extracted from the NCBI GenBank. The epidemiological findings revealed in this study will provide important information on tick-borne diseases in Tanzania and will be used as scientific basis for planning future control strategies.
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16
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Nchu F, Nyangiwe N, Muhanguzi D, Nzalawahe J, Nagagi YP, Msalya G, Joseph NA, Kimaro EG, Mollel M, Temba V, Harouna DV. Development of a practical framework for sustainable surveillance and control of ticks and tick-borne diseases in Africa. Vet World 2020; 13:1910-1921. [PMID: 33132605 PMCID: PMC7566270 DOI: 10.14202/vetworld.2020.1910-1921] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2020] [Accepted: 07/22/2020] [Indexed: 12/24/2022] Open
Abstract
A workshop on ticks and tick-borne diseases (T&TBDs) was held on June 25 and 26, 2019, at the Tropical Pesticides Research Institute, Division of Livestock and Human Diseases Vector Control, Arusha, Tanzania. The objectives of the workshop were to discuss the current situation and to formulate actionable strategies to improve surveillance and control of T&TBDs in Africa. The workshop was funded by the National Research Foundation and the Cape Peninsula University of Technology and attended by livestock health providers, farmers, and researchers from East, West, and Southern African countries. During the workshop, experts presented recent surveillance data focused on T&TBDs; participants discussed research opportunities and community engagement. The primary outcome of the workshop was the creation of a new research consortium known as The African Consortium for T&TBDs. The consortium is intended to function as a community for researchers, students, farmers, policymakers, extension workers, and community members who are interested in the advancement of T&TBD control. The consortium will engage in research activities that focus on comprehensive surveillance of T&TBDs, developing tick acaricide resistance, alternative tick control programs, and policy development and education. These areas were identified as top priorities to be developed to improve T&TBD control on the continent.
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Affiliation(s)
- Felix Nchu
- Department of Horticultural Sciences, Cape Peninsula University of Technology, Bellville, Symphony Way, Bellville, Cape Town, 7535, South Africa
| | - Nkululeko Nyangiwe
- Department of Rural Development and Agrarian Reform, Döhne Agricultural Development Institute, Private Bag X15, Stutterheim 4930, South Africa.,Department of Conservation Ecology and Entomology, University of Stellenbosch, Stellenbosch 7602, South Africa
| | - Dennis Muhanguzi
- Department of Biomolecular and Biolaboratory Sciences, College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, P.O. Box 7062, Kampala, Uganda
| | - Jahashi Nzalawahe
- Department of Veterinary Microbiology, Parasitology and Biotechnology, College of Veterinary Medicine and Biomedical Sciences, Sokoine University of Agriculture, P. O. Box 3019, Chuo Kikuu, Morogoro, Tanzania
| | - Yakob Petro Nagagi
- Division of Livestock and Human Diseases Vector Control, Tropical Pesticides Research Institute, P.O. Box 3024, Arusha, Tanzania
| | - George Msalya
- Department of Animal, Aquaculture and Range Sciences, College of Agriculture, Sokoine University of Agriculture, P. O. Box 3004, Chuo Kikuu, Morogoro, Tanzania.,Laboratory of Animal Breeding and Genetics, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-0065, Japan
| | - Natala Audu Joseph
- Department of Veterinary Parasitology, Faculty of Veterinary Medicine, Ahmadu Bello University, Zaria, Nigeria
| | - Esther Gwae Kimaro
- Division of Livestock and Human Diseases Vector Control, Tropical Pesticides Research Institute, P.O. Box 3024, Arusha, Tanzania
| | - Margaret Mollel
- Division of Livestock and Human Diseases Vector Control, Tropical Pesticides Research Institute, P.O. Box 3024, Arusha, Tanzania
| | - Violet Temba
- Division of Livestock and Human Diseases Vector Control, Tropical Pesticides Research Institute, P.O. Box 3024, Arusha, Tanzania
| | - Difo Voukang Harouna
- Department of Food Biotechnology and Nutritional Sciences, Nelson Mandela African Institution of Science and Technology, P. O. Box 447, Arusha, Tanzania
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17
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Balinandi S, Chitimia-Dobler L, Grandi G, Nakayiki T, Kabasa W, Bbira J, Lutwama JJ, Bakkes DK, Malmberg M, Mugisha L. Morphological and molecular identification of ixodid tick species (Acari: Ixodidae) infesting cattle in Uganda. Parasitol Res 2020; 119:2411-2420. [PMID: 32533261 PMCID: PMC7366568 DOI: 10.1007/s00436-020-06742-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Accepted: 06/01/2020] [Indexed: 12/12/2022]
Abstract
In Uganda, the role of ticks in zoonotic disease transmission is not well described, partly, due to limited available information on tick diversity. This study aimed to identify the tick species that infest cattle. Between September and November 2017, ticks (n = 4362) were collected from 5 districts across Uganda (Kasese, Hoima, Gulu, Soroti, and Moroto) and identified morphologically at Uganda Virus Research Institute. Morphological and genetic validation was performed in Germany on representative identified specimens and on all unidentified ticks. Ticks were belonging to 15 species: 8 Rhipicephalus species (Rhipicephalus appendiculatus, Rhipicephalus evertsi evertsi, Rhipicephalus microplus, Rhipicephalus decoloratus, Rhipicephalus afranicus, Rhipicephalus pulchellus, Rhipicephalus simus, and Rhipicephalus sanguineus tropical lineage); 5 Amblyomma species (Amblyomma lepidum, Amblyomma variegatum, Amblyomma cohaerens, Amblyomma gemma, and Amblyomma paulopunctatum); and 2 Hyalomma species (Hyalomma rufipes and Hyalomma truncatum). The most common species were R. appendiculatus (51.8%), A. lepidum (21.0%), A. variegatum (14.3%), R. evertsi evertsi (8.2%), and R. decoloratus (2.4%). R. afranicus is a new species recently described in South Africa and we report its presence in Uganda for the first time. The sequences of R. afranicus were 2.4% divergent from those obtained in Southern Africa. We confirm the presence of the invasive R. microplus in two districts (Soroti and Gulu). Species diversity was highest in Moroto district (p = 0.004) and geographical predominance by specific ticks was observed (p = 0.001). The study expands the knowledge on tick fauna in Uganda and demonstrates that multiple tick species with potential to transmit several tick-borne diseases including zoonotic pathogens are infesting cattle.
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Affiliation(s)
- Stephen Balinandi
- Uganda Virus Research Institute, P.O. Box 49, Entebbe, Uganda.,College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, P.O. Box 7062, Kampala, Uganda
| | | | - Giulio Grandi
- Section of Virology, Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, Box 7028, 750 07, Uppsala, Sweden
| | - Teddy Nakayiki
- Uganda Virus Research Institute, P.O. Box 49, Entebbe, Uganda
| | - William Kabasa
- College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, P.O. Box 7062, Kampala, Uganda
| | - Johnson Bbira
- College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, P.O. Box 7062, Kampala, Uganda
| | | | - Deon K Bakkes
- Gertrud Theiler Tick Museum, Epidemiology, Parasites and Vectors, Agricultural Research Council - Onderstepoort Veterinary Research, Pretoria, 0110, South Africa.,Evolutionary Genomics Group, Department of Botany and Zoology, Stellenbosch University, Merriman Street, Private Bag X1, Stellenbosch, 7602, South Africa
| | - Maja Malmberg
- Section of Virology, Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, Box 7028, 750 07, Uppsala, Sweden. .,SLU Global Bioinformatics Centre, Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences, Box 7023, 750 07, Uppsala, Sweden.
| | - Lawrence Mugisha
- College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, P.O. Box 7062, Kampala, Uganda.,Ecohealth Research Group, Conservation & Ecosystem Health Alliance, P.O. Box 34153, Kampala, Uganda
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18
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Boucher F, Moutroifi Y, Peba B, Ali M, Moindjie Y, Ruget AS, Abdouroihamane S, Madi Kassim A, Soulé M, Charafouddine O, Cêtre-Sossah C, Cardinale E. Tick-borne diseases in the Union of the Comoros are a hindrance to livestock development: Circulation and associated risk factors. Ticks Tick Borne Dis 2019; 11:101283. [PMID: 31519420 DOI: 10.1016/j.ttbdis.2019.101283] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Revised: 08/20/2019] [Accepted: 08/24/2019] [Indexed: 10/26/2022]
Abstract
Tick-borne diseases (TBD) occur in many temperate countries and are economically important in most tropical and subtropical areas, affecting dairy and beef cattle, as well as small ruminants. Four major tick-borne diseases have been detected in eastern and southern Africa: East Coast fever (ECF) caused by Theileria parva, Theiler 1904, anaplasmosis caused by either Anaplasma marginale, Theiler 1910, Anaplasma centrale, Theiler 1911, or Anaplasma ovis, Bevan 1912, babesiosis caused by Babesia bovis, Babes 1988 and Babesia bigemina, Smith & Kilborne 1893, and heartwater caused by Ehrlichia ruminantium Cowdry 1925. A cross-sectional survey was undertaken to determine the antibody prevalence of these TBDs and to identify the risk factors for TBD infections in the Union of the Comoros. In 2016 and 2017, 903 individual animal serum samples were collected from 429 separate farms, where the farmers answered individual questionnaires. The antibody prevalence of anaplasmosis, babesiosis (B. bigemina) and heartwater was determined by enzyme-linked immunosorbent assays (ELISA) and the antibody prevalence of ECF was assessed using an immunofluorescence antibody test (IFAT). The relationship between TBD seropositivity and livestock-related variables was assessed by multivariate analyses with standard logistic regression models. The results showed that these four TBDs were present in the Union of the Comoros with a global antibody prevalence of 15% (95% CI [12.7%; 17.3%]) for anaplasmosis, 9.2% (95% CI [6.5%, 11.9%]) for B. bigemina babesiosis, 5.3% (95% CI [3.2%, 7.4%]) for ECF and 4.6% (95% CI [3.2%, 6%]) for heartwater. We compared these findings with the abundance and distribution of several tick species known to be TBD vectors and we found a significant correlation between Rhipicephalus appendiculatus and ECF, and between Amblyomma variegatum and heartwater. We also found that two major variables were significantly correlated with B. bigemina antibody prevalence ("island" and "breeding area"), four variables were significantly correlated with anaplasmosis antibody seroprevalence ("island", "number of cattle per farmer", "number of farmers per village" and "breeding area"), two were significantly correlated with ECF antibody prevalence ("number of farmers in village" and "presence of ticks"), and three were significantly correlated with heartwater ("island", "number of cattle per farmer" and "number of farmers in the village"). Our findings confirmed livestock exposure to the four targeted TBDs of major concern for livestock development. Consequently, raising farmers' awareness and setting up a period of quarantine should be considered a priority.
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Affiliation(s)
- F Boucher
- CIRAD, UMR ASTRE, Sainte Clotilde, La Réunion, France; ASTRE, Univ Montpellier (I-MUSE), CIRAD, INRA, Montpellier, France; Direction nationale de l'élevage, Direction nationale des stratégies agricoles et de l'élevage, Vice-présidence en charge du ministère de l'agriculture, de la pêche, de l'environnement de l'aménagement du territoire et de l'urbanisme, Mdé, Bambao, Comoros
| | - Y Moutroifi
- Direction nationale de l'élevage, Direction nationale des stratégies agricoles et de l'élevage, Vice-présidence en charge du ministère de l'agriculture, de la pêche, de l'environnement de l'aménagement du territoire et de l'urbanisme, Mdé, Bambao, Comoros
| | - B Peba
- Onderstepoort Veterinary Institute, 100 Old Soutpan Road, Private Bag X5, 0110 Onderstepoort, South Africa
| | - M Ali
- Direction nationale de l'élevage, Direction nationale des stratégies agricoles et de l'élevage, Vice-présidence en charge du ministère de l'agriculture, de la pêche, de l'environnement de l'aménagement du territoire et de l'urbanisme, Mdé, Bambao, Comoros
| | - Y Moindjie
- Direction nationale de l'élevage, Direction nationale des stratégies agricoles et de l'élevage, Vice-présidence en charge du ministère de l'agriculture, de la pêche, de l'environnement de l'aménagement du territoire et de l'urbanisme, Mdé, Bambao, Comoros
| | - A-S Ruget
- Direction nationale de l'élevage, Direction nationale des stratégies agricoles et de l'élevage, Vice-présidence en charge du ministère de l'agriculture, de la pêche, de l'environnement de l'aménagement du territoire et de l'urbanisme, Mdé, Bambao, Comoros
| | - S Abdouroihamane
- Direction nationale de l'élevage, Direction nationale des stratégies agricoles et de l'élevage, Vice-présidence en charge du ministère de l'agriculture, de la pêche, de l'environnement de l'aménagement du territoire et de l'urbanisme, Mdé, Bambao, Comoros
| | - A Madi Kassim
- Direction nationale de l'élevage, Direction nationale des stratégies agricoles et de l'élevage, Vice-présidence en charge du ministère de l'agriculture, de la pêche, de l'environnement de l'aménagement du territoire et de l'urbanisme, Mdé, Bambao, Comoros
| | - M Soulé
- Direction nationale de l'élevage, Direction nationale des stratégies agricoles et de l'élevage, Vice-présidence en charge du ministère de l'agriculture, de la pêche, de l'environnement de l'aménagement du territoire et de l'urbanisme, Mdé, Bambao, Comoros
| | - O Charafouddine
- Direction nationale de l'élevage, Direction nationale des stratégies agricoles et de l'élevage, Vice-présidence en charge du ministère de l'agriculture, de la pêche, de l'environnement de l'aménagement du territoire et de l'urbanisme, Mdé, Bambao, Comoros
| | - C Cêtre-Sossah
- CIRAD, UMR ASTRE, Sainte Clotilde, La Réunion, France; ASTRE, Univ Montpellier (I-MUSE), CIRAD, INRA, Montpellier, France
| | - E Cardinale
- CIRAD, UMR ASTRE, Sainte Clotilde, La Réunion, France; ASTRE, Univ Montpellier (I-MUSE), CIRAD, INRA, Montpellier, France.
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19
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Kumar R. Molecular markers and their application in the monitoring of acaricide resistance in Rhipicephalus microplus. EXPERIMENTAL & APPLIED ACAROLOGY 2019; 78:149-172. [PMID: 31190248 DOI: 10.1007/s10493-019-00394-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Accepted: 06/03/2019] [Indexed: 06/09/2023]
Abstract
Monitoring acaricide resistance and understanding the underlying mechanisms are critically important in developing strategies for resistance management and tick control. Identification of single nucleotide polymorphisms in the acaricide-resistant associated gene of Rhipicephalus microplus has enabled the development of molecular markers for detection and monitoring of resistance against different types of acaricide. There are many molecular markers developed for resistance monitoring, including mutations on target genes such as sodium channel, acetylcholinesterase, carboxylesterase, β-adrenergic octopamine receptor, octopamine-tyramine etc. Molecular genotyping through molecular markers can detect the presence of resistance-associated genes in a tick population before it reaches high frequency. This review aims to provide an update on the various molecular markers discovered to date from different regions of the world.
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Affiliation(s)
- Rinesh Kumar
- College of Veterinary Science and Animal Husbandry, Rewa, Madhya Pradesh, India.
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20
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Lee S, Kim JY, Yi MH, Lee IY, Fyumagwa R, Yong TS. Comparative microbiomes of ticks collected from a black rhino and its surrounding environment. INTERNATIONAL JOURNAL FOR PARASITOLOGY-PARASITES AND WILDLIFE 2019; 9:239-243. [PMID: 31198683 PMCID: PMC6556756 DOI: 10.1016/j.ijppaw.2019.05.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 05/27/2019] [Accepted: 05/27/2019] [Indexed: 11/04/2022]
Abstract
‘Eliska,’ an endangered black rhino (Diceros bicornis), died suddenly in Mkomazi National Park in Tanzania in 2016. Three Amblyomma gemma ticks were collected from Eliska's body, and four ticks were collected from the surrounding field. We conducted 16S rRNA targeted high-throughput sequencing to evaluate the overall composition of bacteria in the ticks' microbiomes and investigate whether the ticks could be the cause of Eliska's death. The ticks collected from Eliska's body and the field were found to differ in their bacterial composition. Bacillus chungangensis and B. pumilus were the most commonly found bacteria in the ticks collected from the field, and B. cereus and Lysinibacillus sphaericus were the most commonly found in the ticks collected from Eliska's body. The abundance was higher in the ticks collected from the field. In contrast, the equity was higher in the ticks collected from Eliska's body. No known pathogenic bacteria that could explain Eliska's sudden death were found in any of the ticks. The differences between the microbiome of ticks collected from Eliska's body and from the field indicate that the microbiome of ticks' changes through the consumption of blood. Ticks were collected from a dead Black rhino of the endangered species Diceros bicorn. Ticks collected from the body and the surrounding field had different microbiome patterns. Bacillus chungangensis and B. pumilus were commonly found in the ticks collected from the field, and B. cereus and Lysinibacillus sphaericus were commonly found in the ticks collected from Black rhino.
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Affiliation(s)
- Seogwon Lee
- Department of Environmental Medical Biology, Institute of Tropical Medicine, Arthropods of Medical Importance Resource Bank, Yonsei University College of Medicine, Seoul, 03722, South Korea
| | - Ju Yeong Kim
- Department of Environmental Medical Biology, Institute of Tropical Medicine, Arthropods of Medical Importance Resource Bank, Yonsei University College of Medicine, Seoul, 03722, South Korea.,Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, 03722, South Korea
| | - Myung-Hee Yi
- Department of Environmental Medical Biology, Institute of Tropical Medicine, Arthropods of Medical Importance Resource Bank, Yonsei University College of Medicine, Seoul, 03722, South Korea
| | - In-Yong Lee
- Department of Environmental Medical Biology, Institute of Tropical Medicine, Arthropods of Medical Importance Resource Bank, Yonsei University College of Medicine, Seoul, 03722, South Korea
| | - Robert Fyumagwa
- Tanzania Wildlife Research Institute, P.O. Box 661, Arusha, Tanzania
| | - Tai-Soon Yong
- Department of Environmental Medical Biology, Institute of Tropical Medicine, Arthropods of Medical Importance Resource Bank, Yonsei University College of Medicine, Seoul, 03722, South Korea
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21
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Esser HJ, Hartemink NA, de Boer WF. Comment on Titcomb et al.'s 'Interacting effects of wildlife loss and climate on ticks and tick-borne disease'. Proc Biol Sci 2018; 285:rspb.2018.0037. [PMID: 29769356 DOI: 10.1098/rspb.2018.0037] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Accepted: 02/26/2018] [Indexed: 12/26/2022] Open
Affiliation(s)
- H J Esser
- Laboratory of Entomology, Wageningen University & Research, Wageningen, The Netherlands
| | - N A Hartemink
- Laboratory of Entomology, Wageningen University & Research, Wageningen, The Netherlands.,Biometris, Wageningen University & Research, Wageningen, The Netherlands
| | - W F de Boer
- Resource Ecology Group, Wageningen University & Research, Wageningen, The Netherlands
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22
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Robbertse L, Richards SA, Clift SJ, Barnard AC, Leisewitz A, Crafford JE, Maritz-Olivier C. Comparison of the differential regulation of T and B-lymphocyte subsets in the skin and lymph nodes amongst three cattle breeds as potential mediators of immune-resistance to Rhipicephalus microplus. Ticks Tick Borne Dis 2018; 9:976-987. [PMID: 29622516 DOI: 10.1016/j.ttbdis.2018.03.034] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Revised: 03/02/2018] [Accepted: 03/30/2018] [Indexed: 12/20/2022]
Abstract
Although varying natural resistance to ticks between highly resistant Brahman (Bos taurus indicus), resistant Bonsmara (5/8 B. t. indicus x 3/8 B. t. taurus) and susceptible Holstein-Friesian (B. t. taurus) breeds is documented in skin and blood, little information is available describing draining lymph nodes. To elucidate the cellular dynamics during Rhipicephalus microplus induced immune responses, this study analysed immune factors from these cattle breeds using histology, immunohistochemistry and flow cytometry. Following the collection of skin and lymph node samples before artificial tick infestation, cattle were infested with R. microplus larvae. Subsequent sampling coincided with the tick larvae and adult developmental stages. A significant influx of CD20+ B-lymphocytes in the dermis all cattle breeds was observed while CD3+ T-lymphocytes were significantly increased for more tick resistant breeds. Eosinophil infiltration in germinal centres of lymph nodes was significant for all cattle breeds while tingible body macrophages were significantly increased for adult infested Brahman animals. A negligible fluctuation in CD20+ and CD79α+ B-lymphocyte numbers was present in the lymph node of more resistant cattle breeds, while susceptible animals showed a decrease in B-lymphocytes after infestation, followed by an increase between larvae to adult infested time points. Increased variability of γd T-lymphocyte populations in lymph nodes was correlated with tick susceptibility. In addition, a more stable T helper lymphocyte population was identified in the lymph nodes for the Brahman cattle breed. Results suggest the association of tick susceptibility with differential B-lymphocyte regulation in lymph node tissues, increased variability of WC1+ γδ T-lymphocyte populations in the lymph node as well as a decrease in T helper lymphocytes in the lymph node.
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Affiliation(s)
- Luïse Robbertse
- Department of Genetics, Faculty of Natural and Agricultural Sciences, University of Pretoria, South Africa
| | - Sabine Annette Richards
- Department of Genetics, Faculty of Natural and Agricultural Sciences, University of Pretoria, South Africa
| | - Sarah Jane Clift
- Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, South Africa
| | - Annette-Christi Barnard
- Department of Genetics, Faculty of Natural and Agricultural Sciences, University of Pretoria, South Africa
| | - Andrew Leisewitz
- Department of Companion Animal Clinical Studies, Faculty of Veterinary Science, University of Pretoria, South Africa
| | - Jan Ernst Crafford
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, South Africa
| | - Christine Maritz-Olivier
- Department of Genetics, Faculty of Natural and Agricultural Sciences, University of Pretoria, South Africa.
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Prevalence and risk factors associated with Theileria parva infection in cattle in three regions of Tanzania. Trop Anim Health Prod 2017; 49:1613-1621. [PMID: 28752214 DOI: 10.1007/s11250-017-1367-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Accepted: 07/20/2017] [Indexed: 10/19/2022]
Abstract
Ticks and tickborne diseases (TBDs) are serious constraints to cattle production in Tanzania and other tropical and subtropical countries. Among the TBDs, East Coast fever (ECF) is the most important as it causes significant economic losses to the cattle industry in Tanzania. However, control of ECF in Tanzania has continued to be a challenge due to inadequate epidemiological information. The main objective of this study was to determine the epidemiological situation of Theileria parva infections in cattle kept under pastoral and agro-pastoral farming systems in Mara, Singida, and Mbeya regions of Tanzania. Blood samples were collected from 648 cattle in the three regions. Genomic DNA was extracted and amplified in a polymerase chain reaction (PCR) using T. parva-specific primers targeting the 104-kD antigen (P104) gene. In addition, information was collected on the possible risk factors of T. parva infection (animal age, region, animal sex, tick burden, tick control method, and frequency of acaricide application). The prevalence of T. parva across the three regions was 14.2%. There was variation in prevalence among the three regions with Mara (21.8%) having a significantly higher (p = 0.001) prevalence than the other regions. Moreover, Mbeya exhibited relatively lower prevalence (7.4%) compared to the other regions. Factors found to be significantly associated with an animal being PCR positive for T. parva were region (p = 0.001) and tick burden (p = 0.003). Other factors were not found to be significant predictors of being PCR positive for T. parva. The present study showed high variation in tick burden and T. parva prevalence across the regions. Therefore, different strategic planning and cost-effective control measures for ticks and T. parva infection should be implemented region by region in order to reduce losses caused by ticks and ECF in the study area.
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24
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Isack IK, Walter M, Sebastian C, Marja K, Seong-Gu H, Martin S. Abundance and distribution of Ixodid tick species infesting cattle reared under traditional farming systems in Tanzania. ACTA ACUST UNITED AC 2017. [DOI: 10.5897/ajar2016.12028] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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25
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Occurrence of Ticks in Cattle in the New Pastoral Farming Areas in Rufiji District, Tanzania. J Vet Med 2016; 2016:3420245. [PMID: 27990463 PMCID: PMC5136642 DOI: 10.1155/2016/3420245] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Revised: 10/03/2016] [Accepted: 10/19/2016] [Indexed: 11/26/2022] Open
Abstract
Ticks and tick-borne diseases plus trypanosomosis are a constraint to cattle rearing in Tanzania. Rufiji district was not known for important ticks infesting cattle because inhabitants were not engaged in keeping livestock. Not only has settlement of pastoralists and cattle in Rufiji increased the number of cattle but also cattle have been the source of bringing in and spreading of ticks. This study investigated tick species that have been introduced and managed to establish themselves in the new livestock farming areas in cattle in Rufiji. Tick distribution study was undertaken in three villages of Chumbi ward seasonally in 2009, 2011, and 2012. The identified ticks were Amblyomma variegatum (56.10%), Rhipicephalus evertsi (10.25%), R. microplus (27.40%), and R. appendiculatus (6.19%) out of 12940 ticks. Results indicate that ticks are present in the new livestock settlement areas. The occurrence of ticks is correlated with the recent settlement of cattle in the district.
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Genetic diversity, acaricide resistance status and evolutionary potential of a Rhipicephalus microplus population from a disease-controlled cattle farming area in South Africa. Ticks Tick Borne Dis 2016; 7:595-603. [DOI: 10.1016/j.ttbdis.2016.02.018] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Revised: 02/02/2016] [Accepted: 02/24/2016] [Indexed: 11/22/2022]
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27
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Campana MG, Hawkins MTR, Henson LH, Stewardson K, Young HS, Card LR, Lock J, Agwanda B, Brinkerhoff J, Gaff HD, Helgen KM, Maldonado JE, McShea WJ, Fleischer RC. Simultaneous identification of host, ectoparasite and pathogen DNA via in-solution capture. Mol Ecol Resour 2016; 16:1224-39. [DOI: 10.1111/1755-0998.12524] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2015] [Revised: 01/08/2016] [Accepted: 01/19/2016] [Indexed: 11/29/2022]
Affiliation(s)
- Michael G. Campana
- Center for Conservation and Evolutionary Genetics; Smithsonian Conservation Biology Institute; 3001 Connecticut Avenue NW Washington DC 20008 USA
| | - Melissa T. R. Hawkins
- Center for Conservation and Evolutionary Genetics; Smithsonian Conservation Biology Institute; 3001 Connecticut Avenue NW Washington DC 20008 USA
- Division of Mammals; National Museum of Natural History; Smithsonian Institution; MRC 108, P.O. Box 37012 Washington DC 20013-7012 USA
| | - Lauren H. Henson
- Center for Conservation and Evolutionary Genetics; Smithsonian Conservation Biology Institute; 3001 Connecticut Avenue NW Washington DC 20008 USA
| | - Kristin Stewardson
- Center for Conservation and Evolutionary Genetics; Smithsonian Conservation Biology Institute; 3001 Connecticut Avenue NW Washington DC 20008 USA
| | - Hillary S. Young
- Department of Ecology, Evolution and Marine Biology; University of California Santa Barbara; Santa Barbara CA 93106 USA
| | - Leah R. Card
- Smithsonian Conservation Biology Institute; National Zoological Park; 1500 Remount Rd. Front Royal VA 22630 USA
| | - Justin Lock
- Center for Conservation and Evolutionary Genetics; Smithsonian Conservation Biology Institute; 3001 Connecticut Avenue NW Washington DC 20008 USA
| | | | - Jory Brinkerhoff
- Department of Biology; B322 Gottwald Center for the Sciences; University of Richmond; 28 Westhampton Way Richmond VA 23173 USA
| | - Holly D. Gaff
- Department of Biological Sciences; Old Dominion University; Norfolk VA 23529 USA
| | - Kristofer M. Helgen
- Division of Mammals; National Museum of Natural History; Smithsonian Institution; MRC 108, P.O. Box 37012 Washington DC 20013-7012 USA
| | - Jesús E. Maldonado
- Center for Conservation and Evolutionary Genetics; Smithsonian Conservation Biology Institute; 3001 Connecticut Avenue NW Washington DC 20008 USA
- Division of Mammals; National Museum of Natural History; Smithsonian Institution; MRC 108, P.O. Box 37012 Washington DC 20013-7012 USA
| | - William J. McShea
- Smithsonian Conservation Biology Institute; National Zoological Park; 1500 Remount Rd. Front Royal VA 22630 USA
| | - Robert C. Fleischer
- Center for Conservation and Evolutionary Genetics; Smithsonian Conservation Biology Institute; 3001 Connecticut Avenue NW Washington DC 20008 USA
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High seroprevalence for spotted fever group rickettsiae, is associated with higher temperatures and rural environment in Mbeya region, Southwestern Tanzania. PLoS Negl Trop Dis 2015; 9:e0003626. [PMID: 25849718 PMCID: PMC4388512 DOI: 10.1371/journal.pntd.0003626] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Accepted: 02/18/2015] [Indexed: 12/03/2022] Open
Abstract
Background Rickettsioses are endemic in sub-Sahara Africa. Burden of disease, risk factors and transmission are hitherto sparsely described. Methods From the EMINI (Evaluating and Monitoring the Impact of New Interventions) population cohort, we randomly selected 1,228 persons above the age of 5 years from the nine participating communities in Mbeya region, Southwestern Tanzania, stratified by age, altitude of residence and ownership of domestic mammals, to conduct a cross-sectional seroprevalence study in. The aim was to estimate the seroprevalence of IgG antibodies against Spotted Fever Group (SFG) rickettsiae and to assess socioeconomic and environmental risk factors. Serology (indirect immunofluorescence) was performed at a dilution of 1:64. Results SFG-seropositivity in the cohort was found to be 67.9% (range among nine sites: 42.8–91.4%). Multivariable analysis revealed an association with age (prevalence ratio, PR per 10 years: 1.08; 95% CI 1.06–1.10), warmer temperatures (PR per °C: 1.38; 1.11–1.71), male gender (PR 1.08; 1.00–1.16), and low population density (PR per 1.000 persons/km²increase 0.96; 0.94–0.99). At higher elevations, higher cattle density was associated with higher seroprevalence. Conclusion SFG rickettsial infection seems to be common in the more rural population of Mbeya Region. Spread seems to be further limited by temperature and higher elevation. Examination of the contribution of SFG to febrile illnesses seems warranted in a prospective study to estimate the disease burden in the population. This will also allow determination of the causative pathogens. We report a high seroprevalence for antibodies against Spotted Fever Group (SFG) rickettsiae in Southwestern Tanzania, a group of bacteria that is mostly transmitted by ectoparasites such as fleas, lice, mites, and ticks. Serum samples from 1.228 persons were selected, and 67.9% were positive indicating past infection. Seropositivity was clearly associated with warmer temperature, low population density and elevations below 1,500 m. These infections may have been caused by Rickettsia africae, which is transmitted to humans by a cattle tick, and was found in similar settings in Africa. To investigate further on the significance of SFG rickettsioses on disease burden in the area, investigations in acutely febrile patients should be conducted.
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Kwak YS, Kim TY, Nam SH, Lee IY, Kim HP, Mduma S, Keyyu J, Fyumagwa R, Yong TS. Ixodid tick infestation in cattle and wild animals in Maswa and Iringa, Tanzania. THE KOREAN JOURNAL OF PARASITOLOGY 2014; 52:565-8. [PMID: 25352709 PMCID: PMC4210743 DOI: 10.3347/kjp.2014.52.5.565] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Revised: 07/17/2014] [Accepted: 08/03/2014] [Indexed: 11/23/2022]
Abstract
Ticks and tick-borne diseases are important in human and livestock health worldwide. In November 2012, ixodid ticks were collected and identified morphologically from cattle and wild animals in the Maswa district and Iringa urban, Tanzania. Amblyomma gemma, A. lepidum, and A. variegatum were identified from Maswa cattle, and A. variegatum was the predominant species. A. marmoreum, Hyalomma impeltatum, and Rhipicephalus pulchellus were identified from Iringa cattle in addition to the above 3 Amblyomma species, and A. gemma was the most abundant species. Total 4 Amblyomma and 6 Rhipicephalus species were identified from wild animals of the 2 areas. A. lepidum was predominant in Maswa buffaloes, whereas A. gemma was predominant in Iringa buffaloes. Overall, A. variegatum in cattle was predominant in the Maswa district and A. gemma was predominant in Iringa, Tanzania.
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Affiliation(s)
- You Shine Kwak
- Department of Environmental Medical Biology and Institute of Tropical Medicine, Yonsei University College of Medicine, Seoul 120-752, Korea. ; Arthropods of Medical Importance Resource Bank, Yonsei University College of Medicine, Seoul 120-752, Korea. ; Department of Microbiology, Ajou University School of Medicine, Suwon 443-380, Korea
| | - Tae Yun Kim
- Department of Environmental Medical Biology and Institute of Tropical Medicine, Yonsei University College of Medicine, Seoul 120-752, Korea. ; Arthropods of Medical Importance Resource Bank, Yonsei University College of Medicine, Seoul 120-752, Korea
| | - Sung-Hyun Nam
- Department of Environmental Medical Biology and Institute of Tropical Medicine, Yonsei University College of Medicine, Seoul 120-752, Korea. ; Arthropods of Medical Importance Resource Bank, Yonsei University College of Medicine, Seoul 120-752, Korea
| | - In-Yong Lee
- Department of Environmental Medical Biology and Institute of Tropical Medicine, Yonsei University College of Medicine, Seoul 120-752, Korea. ; Arthropods of Medical Importance Resource Bank, Yonsei University College of Medicine, Seoul 120-752, Korea
| | - Hyung-Pyo Kim
- Department of Environmental Medical Biology and Institute of Tropical Medicine, Yonsei University College of Medicine, Seoul 120-752, Korea
| | - Simon Mduma
- Tanzania Wildlife Research Institute, P.O. Box 661, Arusha, Tanzania
| | - Julius Keyyu
- Tanzania Wildlife Research Institute, P.O. Box 661, Arusha, Tanzania
| | - Robert Fyumagwa
- Tanzania Wildlife Research Institute, P.O. Box 661, Arusha, Tanzania
| | - Tai-Soon Yong
- Department of Environmental Medical Biology and Institute of Tropical Medicine, Yonsei University College of Medicine, Seoul 120-752, Korea. ; Arthropods of Medical Importance Resource Bank, Yonsei University College of Medicine, Seoul 120-752, Korea
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30
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Yssouf A, Socolovschi C, Kernif T, Temmam S, Lagadec E, Tortosa P, Parola P. First molecular detection of Rickettsia africae in ticks from the Union of the Comoros. Parasit Vectors 2014; 7:444. [PMID: 25245895 PMCID: PMC4289259 DOI: 10.1186/1756-3305-7-444] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Accepted: 09/09/2014] [Indexed: 11/22/2022] Open
Abstract
Background Rickettsia africae is the agent of African tick bite fever, a disease transmitted by ticks in sub-Saharan Africa. In Union of the Comoros, a recent study reported the presence of a Rickettsia africae vector but no information has been provided on the circulation of the pathogenic agent in this country. Methods To evaluate the possible circulation of Rickettsia spp. in Comorian cattle, genomic DNA was extracted from 512 ticks collected either in the Union of the Comoros or from animals imported from Tanzania and subsequently tested for Rickettsia infection by quantitative PCR. Results Rickettsia africae was detected in 90% (60/67) of Amblyomma variegatum, 1% (1/92) of Rhipicephalus appendiculatus and 2.7% (8/296) of Rhipicephalus (Boophilus) microplus ticks collected in the Union of the Comoros, as well as in 77.14% (27/35) of Amblyomma variegatum ticks collected from imported cattle. Partial sequences of both bacterial gltA and ompA genes were used in a phylogenetic analysis revealing the presence of several haplotypes, all included within the Rickettsia africae clade. Conclusions Our study reports the first evidence of Rickettsia africae in ticks collected from the Union of the Comoros. The data show a significant difference of infection rate of Rickettsia africae infected ticks between the Islands, with maximum rates measured in Grande Comore Island, sheltering the main entry port for live animal importation from Tanzania. The high infection levels reported herein indicate the need for an in-depth assessment of the burden of rickettsioses in the Union of the Comoros, especially among those at risk of infection, such as cattle herders.
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Affiliation(s)
| | | | | | | | | | | | - Philippe Parola
- Aix Marseille Université, Unité de Recherche en Maladies Infectieuses et Tropicales Emergentes (URMITE), UM63, CNRS 7278, IRD 198, Inserm 1095, WHO Collaborative Center for Rickettsioses and Other Arthropod-borne Bacterial Diseases, Faculté de Médecine, 27 bd Jean Moulin, 13385 Marseille cedex 5, France.
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Hezron E N, Adrian M, Robinson H M. Tick infestations in extensively grazed cattle and efficacy trial of high-cis cypermethrin pour-on preparation for control of ticks in Mvomero district in Tanzania. BMC Vet Res 2012; 8:224. [PMID: 23164198 PMCID: PMC3556501 DOI: 10.1186/1746-6148-8-224] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2011] [Accepted: 11/16/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND This study aimed at determining the extent of tick infestations in extensively grazed cattle and assess the efficacy of Ecotix® acaricide (2.5% high cis cypermethrin) in Mvomero district in Tanzania. A total of 1200 Tanzanian short horn Zebu (TSHZ) from two farms in two villages were qualitatively assessed for tick infestations and 40 animals (grouped in 10s from each farm) were separated in their herds and quantitatively examined to establish the tick load. The animals were grouped in treatment regime groups (TxRG 1, 2, 3, and 4), TxRG 1 being the control group was treated with water. Ecotix® was applied on day 0 for TxRG 2, days 0 and 7 for TxRG 3 and days 0, 7 and 14 for TxRG 4 and tick load was monitored for 28 days. RESULTS All the animals examined were infested with ticks. The identified ticks were Rhipicephalus appendiculatus (55%), Amblyomma variegatum (18%), R. (Boophilus) microplus (12.9%), R. (B) decoloratus (7.1%), R. evertsi evertsi (4.4%) and R. composites (2.6%). The overall mean (mean±SEM) tick density on day zero was 63±30 ticks per animal (ranging from 20-160). The mean tick density on day zero was 44.6±25.4, 74.6±30.3, 55.0±26.2 and 77±33.5 for groups one, two, three and four respectively. Post-treatment quantitative assessment of tick burden revealed that the TxRG 1 animals maintained a tick load throughout the study period. A significant decrease in tick load in animals in groups TxRG 2, 3 and 4 (P=0.0001) with increasing frequency of Ecotix® application was recorded. There was however no significant difference in tick reduction between TxRG 3 and 4 (P=0.0986). Thus TxRG 3 would be sufficient for the monthly tick treatment and with this regime, the farmer would save up to 2.5 USD per animal during six months of dry season. CONCLUSIONS The study revealed a high tick infestation among the TSHZ kept in extensive grazing systems in Mvomero district and that when treated with Ecotix® as pour-on preparation using a two application regime per month, the tick control strategy was effective.
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Affiliation(s)
- Nonga Hezron E
- Department of Veterinary Medicine and Public Health, Sokoine University of Agriculture, PO Box 3021, Morogoro, Tanzania.
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Rodríguez-Valle M, Taoufik A, Valdés M, Montero C, Hassan I, Hassan SM, Jongejan F, de la Fuente J. Efficacy of Rhipicephalus (Boophilus) microplus Bm86 against Hyalomma dromedarii and Amblyomma cajennense tick infestations in camels and cattle. Vaccine 2012; 30:3453-8. [DOI: 10.1016/j.vaccine.2012.03.020] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2012] [Revised: 02/13/2012] [Accepted: 03/08/2012] [Indexed: 02/05/2023]
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Fyumagwa RD, Simmler P, Meli ML, Hoare R, Hofmann-Lehmann R, Lutz H. Molecular Detection ofAnaplasma, BabesiaandTheileriaSpecies in a Diversity of Tick Species from Ngorongoro Crater, Tanzania. ACTA ACUST UNITED AC 2011. [DOI: 10.3957/056.041.0109] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
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Chitimia L, Lin RQ, Cosoroaba I, Wu XY, Song HQ, Yuan ZG, Zhu XQ. Genetic characterization of ticks from southwestern Romania by sequences of mitochondrial cox1 and nad5 genes. EXPERIMENTAL & APPLIED ACAROLOGY 2010; 52:305-311. [PMID: 20473707 DOI: 10.1007/s10493-010-9365-9] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2010] [Accepted: 04/19/2010] [Indexed: 05/29/2023]
Abstract
In the present study, samples representing three hard tick species and one soft tick species, namely Dermacentor marginatus, Haemaphysalis punctata, Ixodes ricinus and Argas persicus from southwestern Romania, and one hard tick, Haemaphysalis longicornis, from China were characterized genetically by a portion of mitochondrial cytochrome c oxidase subunit 1 gene (pcox1) and a portion of nicotinamide adenine dinucleotide dehydrogenase subunit 5 gene (pnad5). The pcox1 and pnad5 were amplified separately from individual ticks by PCR, sequenced and analyzed. The length of pcox1 and pnad5 sequences of all samples was 732 and 519 bp, respectively. The intra-specific sequence variation in De. marginatus was 0.1-1.0% for pcox1 and 0.2-1.2% for pnad5, whereas in Ha. punctata it was 0.4-1.9% for pcox1 and 0.4-1.0% for pnad5. For the tick species examined in the present study, sequence comparison revealed that the inter-specific sequence differences were higher: 15.9-27.6% for pcox1 and 20.3-42.4% for pnad5. This suggests that the cox1 and nad5 sequences could provide useful genetic markers for the specific identification and genetic characterization of ticks in Romania and elsewhere.
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Affiliation(s)
- Lidia Chitimia
- Department of Parasitology, College of Veterinary Medicine, South China Agricultural University, Guangzhou, Guangdong Province, 510642, People's Republic of China
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Fyumagwa RD, Simmler P, Meli ML, Hoare R, Hofmann-Lehmann R, Lutz H. Prevalence of Anaplasma marginale in different tick species from Ngorongoro Crater, Tanzania. Vet Parasitol 2009; 161:154-7. [PMID: 19201099 DOI: 10.1016/j.vetpar.2008.12.018] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2008] [Revised: 12/15/2008] [Accepted: 12/23/2008] [Indexed: 11/16/2022]
Abstract
In 2001, Ngorongoro Crater was infested with high density of ticks on grassland, livestock and wildlife which was also associated with high mortality. Adult ticks were collected, identified, processed for nucleic acids extraction and a molecular analysis was performed to determine the range of tick species harboring Anaplasma marginale. The real-time PCR was used in the amplification of rickettsia DNA in tick pools (n=527) from 11 identified tick species. Six tick species were detected with A. marginale DNA including Amblyomma gemma, Rhipicephalus appendiculatus, R. compositus, R.decoloratus, R. praetextatus and R. pulchellus. The detection rate in each tick species was 3%, 0.7%, 2%, 13%, 1.8%, and 6.2%, respectively. Five of the positive tick species excluding R.decoloratus have previously not been described to transmit A. marginale. High diversity of tick species detected with A. marginale in Ngorongoro Crater is likely to increase a risk to susceptible animals of contracting the infection.
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Affiliation(s)
- Robert D Fyumagwa
- Tanzania Wildlife Research Institute (TAWIRI) Wildlife Veterinary Programme, P.O. Box 661, Arusha, Tanzania.
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Swai ES, Moshy W, Mtui PF, Bwanga S, Machange G, Sanka P. Serological survey of antibodies to Ehrlichia ruminantium in small ruminants in Tanzania. Trop Anim Health Prod 2008; 41:959-67. [DOI: 10.1007/s11250-008-9285-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2008] [Accepted: 11/27/2008] [Indexed: 10/21/2022]
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Lynen G, Zeman P, Bakuname C, Di Giulio G, Mtui P, Sanka P, Jongejan F. Shifts in the distributional ranges of Boophilus ticks in Tanzania: evidence that a parapatric boundary between Boophilus microplus and B. decoloratus follows climate gradients. EXPERIMENTAL & APPLIED ACAROLOGY 2008; 44:147-164. [PMID: 18266058 DOI: 10.1007/s10493-008-9134-1] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2007] [Accepted: 01/22/2008] [Indexed: 05/25/2023]
Abstract
Based on a national tick survey conducted in Tanzania between 1998 and 2001, predictive maps of tick distribution for B. microplus and B. decoloratus were computed and compared with historical maps that originated about 40 years ago. The new data collected showed that except for extremely cold and dry areas B. microplus has extended its distribution range and is now present in all the northern regions of Tanzania, and that high suitability is currently recorded for most of the previously non-occupied areas. In contrast, B. decoloratus, once abundant in Tanzania, has largely retreated to highlands in north and central Tanzania and several other high-altitude refuges. Geostatistical analysis revealed a dissimilar character of distribution for the two species at a local and regional scale, as well as an antagonistic relationship between them in a spatial context. The Tanzania data suggest that an equilibrium phase with a stable parapatric boundary that follows a climate gradient has been achieved. The zone of overlap in the distribution ranges of B. microplus and B. decoloratus is characterized by a decreased infestation rate as well as mutual exclusion on infested cattle. This finding matches studies on parapatry with hybrid zones, where the latter zones that separate species tend to rest in density troughs. Analysis of the Tanzania data shows that the critical factor for the advance of B. microplus and the retreat of B. decoloratus is associated with the 58 mm isohyet and the 22-23 degrees C isotherm and indicates a well developed higher-temperature tolerance for B. microplus. It can be anticipated that climate changes may enhance the spread of B. microplus and consequently Babesia bovis into new areas of the African continent.
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Affiliation(s)
- Godelieve Lynen
- Ministry of Water and Livestock Development, Veterinary Investigation Centre, P.O. Box 1068, Arusha, Tanzania.
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