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Poh KC, Aguilar M, Capelli-Peixoto J, Davis SK, Ueti MW. Haemaphysalis longicornis (Acari: Ixodidae) does not transmit Babesia bovis, a causative agent of cattle fever. Ticks Tick Borne Dis 2024; 15:102374. [PMID: 38971081 DOI: 10.1016/j.ttbdis.2024.102374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Revised: 06/25/2024] [Accepted: 06/26/2024] [Indexed: 07/08/2024]
Abstract
The Asian longhorned tick (Haemaphysalis longicornis) was first reported in the United States in 2017 and has since been detected in at least 17 states. This tick infests cattle and can produce large populations quickly due to its parthenogenetic nature, leading to significant livestock mortalities and economic losses. While H. longicornis has not been detected in Texas, species distribution models have identified southern Texas as a possible hospitable region for this tick. Southern Texas is currently home to the southern cattle tick (Rhipicephalus microplus), which can transmit the causative agent of cattle fever (Babesia bovis). With the potential for H. longicornis and B. bovis to overlap in southern Texas and their potential to negatively impact the national and global livestock industry, it is imperative to identify the role H. longicornis may play in the cattle fever disease system. A controlled acquisition and transmission experiment tested whether H. longicornis is a vector for B. bovis, with the R. microplus-B. bovis system used as a positive control. Transstadial (nymphs to adults) and transovarial (adults to larvae) transmission and subsequent transstadial maintenance (nymphs and adults) routes were tested in this study. Acquisition-fed, splenectomized animals were used to increase the probability of tick infection. Acquisition nymphs were macerated whole and acquisition adults were dissected to remove midguts and ovaries at five time points (4, 6, 8, 10, and 12 days post-repletion), with 40 ticks processed per time point and life stage. The greatest percentage of nymphs with detectable B. bovis DNA occurred six days post-repletion (20.0 %). For adults, the percentage of positive midguts and ovaries increased as days post-repletion progressed, with day 12 having the highest percentage of positive samples (67.5 % and 60.0 %, respectively). When egg batches were tested in triplicate, all H. longicornis egg batches were negative for B. bovis, while all R. microplus egg batches were positive for B. bovis. During the transmission phase, the subsequent life stages for transstadial (adults) and transovarial transmission/transstadial maintenance (larvae, nymphs, and adults) were fed on naïve, splenectomized calves. All life stages of H. longicornis ticks tested during transmission were negative for B. bovis. Furthermore, the transmission fed animals were also negative for B. bovis and did not show signs of bovine babesiosis during the 45-day post tick transmission period. Given the lack of successful transstadial or transovarial transmission, it is unlikely that H. longicornis is a vector for B. bovis.
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Affiliation(s)
- Karen C Poh
- Animal Disease Research Unit, Agricultural Research Service, United States Department of Agriculture, 3003 Animal Disease and Biotechnology Facility, Pullman, WA 99164, USA.
| | - Mitzi Aguilar
- Department of Veterinary Microbiology and Pathology, Washington State University, 3003 Animal Disease and Biotechnology Facility, Pullman, WA 99164, USA
| | - Janaína Capelli-Peixoto
- Department of Veterinary Microbiology and Pathology, Washington State University, 3003 Animal Disease and Biotechnology Facility, Pullman, WA 99164, USA
| | - Sara K Davis
- Animal Disease Research Unit, Agricultural Research Service, United States Department of Agriculture, 3003 Animal Disease and Biotechnology Facility, Pullman, WA 99164, USA
| | - Massaro W Ueti
- Animal Disease Research Unit, Agricultural Research Service, United States Department of Agriculture, 3003 Animal Disease and Biotechnology Facility, Pullman, WA 99164, USA
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Rojas MJ, Bastos RG, Navas J, Laughery JM, Lacy PA, Suarez CE. A conserved motif in the immune-subdominant RAP-1 related antigen of Babesia bovis contains a B-cell epitope recognized by antibodies from protected cattle. Front Immunol 2024; 15:1380660. [PMID: 38720894 PMCID: PMC11076753 DOI: 10.3389/fimmu.2024.1380660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Accepted: 04/10/2024] [Indexed: 05/12/2024] Open
Abstract
Introduction Babesia bovis, a tick-borne apicomplexan parasite causing bovine babesiosis, remains a significant threat worldwide, and improved and practical vaccines are needed. Previous studies defined the members of the rhoptry associated protein-1 (RAP-1), and the neutralization-sensitive rhoptry associated protein-1 related antigen (RRA) superfamily in B. bovis, as strong candidates for the development of subunit vaccines. Both RAP-1 and RRA share conservation of a group of 4 cysteines and amino acids motifs at the amino terminal end (NT) of these proteins. Methods and results Sequence comparisons among the RRA sequences of several B. bovis strains and other Babesia spp parasites indicate a high level of conservation of a 15-amino acid (15-mer) motif located at the NT of the protein. BlastP searches indicate that the 15-mer motif is also present in adenylate cyclase, dynein, and other ATP binding proteins. AlphaFold2 structure predictions suggest partial exposure of the 15-mer on the surface of RRA of three distinct Babesia species. Antibodies in protected cattle recognize a synthetic peptide representing the 15-mer motif sequence in iELISA, and rabbit antibodies against the 15-mer react with the surface of free merozoites in immunofluorescence. Discussion and conclusion The presence of the 15-mer-like regions in dynein and ATP-binding proteins provides a rationale for investigating possible functional roles for RRA. The demonstrated presence of a surface exposed B-cell epitope in the 15-mer motif of the B. bovis RRA, which is recognized by sera from protected bovines, supports its inclusion in future subunit epitope-based vaccines against B. bovis.
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Affiliation(s)
- Manuel J. Rojas
- Department of Veterinary Microbiology & Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA, United States
- Animal Health Department, Universidad Nacional de Colombia, Bogotá, Colombia
| | - Reginaldo G. Bastos
- Department of Veterinary Microbiology & Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA, United States
- Animal Disease Research Unit, Agricultural Research Service, United States Department of Agriculture, Pullman, WA, United States
| | - Jinna Navas
- Department of Veterinary Microbiology & Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA, United States
| | - Jacob M. Laughery
- Department of Veterinary Microbiology & Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA, United States
| | - Paul A. Lacy
- Animal Disease Research Unit, Agricultural Research Service, United States Department of Agriculture, Pullman, WA, United States
| | - Carlos E. Suarez
- Department of Veterinary Microbiology & Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA, United States
- Animal Disease Research Unit, Agricultural Research Service, United States Department of Agriculture, Pullman, WA, United States
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Zhang J, Wang J, Kelly PJ, Zhang Y, Li M, Li J, Zhang R, Wang Y, Huang K, You J, Qiu H, Zheng X, Wang X, Li J, Dong J, Yang Y, Wang C. Experimental infection and co-infection with Chinese strains of Ehrlichia canis and Babesia vogeli in intact and splenectomized dogs: Insights on clinical, hematologic and treatment responses. Vet Parasitol 2023; 323:110032. [PMID: 37783174 DOI: 10.1016/j.vetpar.2023.110032] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 09/20/2023] [Accepted: 09/22/2023] [Indexed: 10/04/2023]
Abstract
Animal infection models are crucial for studying various aspects of Ehrlichia canis infections. To understand the pathogenesis of the first Chinese isolate of E. canis and simulate the natural progression of canine ehrlichiosis, we developed a model with 18 Beagle dogs that consisted of E. canis initial infection (days 0-17), treatment with doxycycline or rifampicin (days 18-32), recovery (days 33-66), E. canis reinfection (days 67-91), and Babesia vogeli superinfection (days 92-116). We measured body weight and rectal temperature every other day, drew blood every 4 days for routine hematology and biochemistry tests, and for quantification of E. canis and B. vogeli by quantitative PCRs. In this study, the first isolate of E. canis from China was used to experimentally infect dogs, and the infected dogs exhibited clinical signs of acute severe ehrlichiosis, including high fever, loss of appetite, dehydration, and body weight loss, confirming the similar pathogenicity of E. canis in China as compared to isolates from other regions. Infection with E. canis and B. vogeli led to reduced body weight and fever in dogs. Doxycycline treatment led to absence of E. canis DNA in infected dogs, while rifampicin treatment lowered the blood E. canis copy number up to 1.5 folds. E. canis-free infected dogs after doxycycline treatment were successfully re-infected with E. canis, indicating dogs with antibodies are still at risk of re-infection. Super-infection with B. vogeli resulted in higher fever, more severe anemia, and a reduced number of platelets. Splenectomized dogs showed significantly higher E. canis numbers during recovery and re-infection than intact dogs. The histological changes were observed in brain, lung, kidney, liver and spleen of the infected dogs. The findings in this study provide insights into clinical and hematologic responses, as well as effective treatment options, for dogs infected with the first Chinese isolate of E. canis, and may contribute to our understanding of the diagnosis and prevention of tick-borne diseases in dogs, including canine monocytic ehrlichiosis.
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Affiliation(s)
- Jilei Zhang
- Yangzhou University College of Veterinary Medicine, Yangzhou, Jiangsu, China; College of Medicine, University of Illinois Chicago, Chicago, IL, USA
| | - Jiawei Wang
- Yangzhou University College of Veterinary Medicine, Yangzhou, Jiangsu, China
| | | | - Yuanyuan Zhang
- Yangzhou University College of Veterinary Medicine, Yangzhou, Jiangsu, China
| | - Min Li
- Yangzhou University College of Veterinary Medicine, Yangzhou, Jiangsu, China
| | - Jing Li
- Yangzhou University College of Veterinary Medicine, Yangzhou, Jiangsu, China
| | - Rong Zhang
- Yangzhou University College of Veterinary Medicine, Yangzhou, Jiangsu, China
| | - Yaoyao Wang
- Yangzhou University College of Veterinary Medicine, Yangzhou, Jiangsu, China
| | - Ke Huang
- Yangzhou University College of Veterinary Medicine, Yangzhou, Jiangsu, China
| | - Jinfeng You
- Yangzhou University College of Veterinary Medicine, Yangzhou, Jiangsu, China
| | - Haixiang Qiu
- Yangzhou University College of Veterinary Medicine, Yangzhou, Jiangsu, China
| | - Xiaofeng Zheng
- Jiangsu Agri-animal Husbandry Vocational College, Taizhou, Jiangsu, China
| | - Xiaobo Wang
- Yangzhou University College of Veterinary Medicine, Yangzhou, Jiangsu, China
| | - Jianji Li
- Yangzhou University College of Veterinary Medicine, Yangzhou, Jiangsu, China
| | - Junsheng Dong
- Yangzhou University College of Veterinary Medicine, Yangzhou, Jiangsu, China
| | - Yi Yang
- Yangzhou University College of Veterinary Medicine, Yangzhou, Jiangsu, China.
| | - Chengming Wang
- College of Veterinary Medicine, Auburn University, Auburn, AL, USA.
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Silva MG, Bastos RG, Laughery JM, Alzan HF, Rathinasamy VA, Cooke BM, Suarez CE. Vaccination of cattle with the Babesia bovis sexual-stage protein HAP2 abrogates parasite transmission by Rhipicephalus microplus ticks. NPJ Vaccines 2023; 8:140. [PMID: 37758790 PMCID: PMC10533483 DOI: 10.1038/s41541-023-00741-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 09/15/2023] [Indexed: 09/29/2023] Open
Abstract
The apicomplexan parasite Babesia bovis is responsible for bovine babesiosis, a poorly controlled tick-borne disease of global impact. The widely conserved gametocyte protein HAPLESS2/GCS1 (HAP2) is uniquely expressed on the surface of B. bovis sexual stage parasites and is a candidate for transmission-blocking vaccines (TBV). Here, we tested whether vaccination of calves with recombinant HAP2 (rHAP2) interferes with the transmission of B. bovis by competent ticks. Calves vaccinated with rHAP2 (n = 3), but not control animals (n = 3) developed antibodies specific to the vaccine antigen. Vaccinated and control animals were infested with Rhipicephalus microplus larvae and subsequently infected with virulent blood stage B. bovis parasites by needle inoculation, with all animals developing clinical signs of acute babesiosis. Engorged female ticks fed on the infected calves were collected for oviposition, hatching, and obtention of larvae. Transmission feeding was then conducted using pools of larvae derived from ticks fed on rHAP2-vaccinated or control calves. Recipient calves (n = 3) exposed to larvae derived from control animals, but none of the recipient calves (n = 3) challenged with larvae from ticks fed on rHAP2-vaccinated animals, developed signs of acute babesiosis within 11 days after tick infestation. Antibodies against B. bovis antigens and parasite DNA were found in all control recipient animals, but not in any of the calves exposed to larvae derived from HAP2-vaccinated animals, consistent with the absence of B. bovis infection via tick transmission. Overall, our results are consistent with the abrogation of parasite tick transmission in rHAP2-vaccinated calves, confirming this antigen as a prime TBV candidate against B. bovis.
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Affiliation(s)
- Marta G Silva
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA, USA
| | - Reginaldo G Bastos
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA, USA
- Animal Disease Research Unit, United States Department of Agricultural - Agricultural Research Service, Pullman, WA, USA
| | - Jacob M Laughery
- Animal Disease Research Unit, United States Department of Agricultural - Agricultural Research Service, Pullman, WA, USA
| | - Heba F Alzan
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA, USA
- Parasitology and Animal Diseases Department, National Research Center, Dokki, Giza, Egypt
| | - Vignesh A Rathinasamy
- Australian Institute of Tropical Health & Medicine, James Cook University, Cairns, QLD, Australia
| | - Brian M Cooke
- Australian Institute of Tropical Health & Medicine, James Cook University, Cairns, QLD, Australia
| | - Carlos E Suarez
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA, USA.
- Animal Disease Research Unit, United States Department of Agricultural - Agricultural Research Service, Pullman, WA, USA.
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Santos JHM, Siddle HV, Raza A, Stanisic DI, Good MF, Tabor AE. Exploring the landscape of Babesia bovis vaccines: progress, challenges, and opportunities. Parasit Vectors 2023; 16:274. [PMID: 37563668 PMCID: PMC10413621 DOI: 10.1186/s13071-023-05885-z] [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: 05/24/2023] [Accepted: 07/17/2023] [Indexed: 08/12/2023] Open
Abstract
Bovine babesiosis, caused by different Babesia spp. such as B. bovis, B. bigemina, B. divergens, and B. major, is a global disease that poses a serious threat to livestock production. Babesia bovis infections are associated with severe disease and increased mortality in adult cattle, making it the most virulent agent of bovine babesiosis. Babesia bovis parasites undergo asexual reproduction within bovine red blood cells, followed by sexual reproduction within their tick vectors, which transmit the parasite transovarially. Current control methods, including therapeutic drugs (i.e., imidocarb) have been found to lead to drug resistance. Moreover, changing environmental factors add complexity to efficient parasite control. Understanding the fundamental biology, host immune responses, and host-parasite interactions of Babesia parasites is critical for developing next-generation vaccines to control acute disease and parasite transmission. This systematic review analyzed available research papers on vaccine development and the associated immune responses to B. bovis. We compiled and consolidated the reported vaccine strategies, considering the study design and rationale of each study, to provide a systematic review of knowledge and insights for further research. Thirteen studies published since 2014 (inclusive) represented various vaccine strategies developed against B. bovis such as subunit, live attenuated, and viral vector vaccines. Such strategies incorporated B. bovis proteins or whole live parasites with the latter providing the most effective prophylaxis against bovine babesiosis. Incorporating novel research approaches, such as "omics" will enhance our understanding of parasite vulnerabilities.
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Affiliation(s)
- John Harvey M Santos
- The University of Queensland, Queensland Alliance for Agriculture & Food Innovation, Centre for Animal Science, St Lucia, Qld, 4072, Australia
| | - Hannah V Siddle
- The University of Queensland, Queensland Alliance for Agriculture & Food Innovation, Centre for Animal Science, St Lucia, Qld, 4072, Australia
| | - Ali Raza
- The University of Queensland, Queensland Alliance for Agriculture & Food Innovation, Centre for Animal Science, St Lucia, Qld, 4072, Australia
| | - Danielle I Stanisic
- Griffith University, Institute for Glycomics, Southport, Qld, 4215, Australia
| | - Michael F Good
- Griffith University, Institute for Glycomics, Southport, Qld, 4215, Australia
| | - Ala E Tabor
- The University of Queensland, Queensland Alliance for Agriculture & Food Innovation, Centre for Animal Science, St Lucia, Qld, 4072, Australia.
- The University of Queensland, School of Chemistry & Molecular Biosciences, St Lucia, Qld, 4072, Australia.
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Hakimi H, Verocai GG. Babesia bovis. Trends Parasitol 2023; 39:708-709. [PMID: 37280144 DOI: 10.1016/j.pt.2023.05.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 05/12/2023] [Accepted: 05/15/2023] [Indexed: 06/08/2023]
Affiliation(s)
- Hassan Hakimi
- Department of Veterinary Pathobiology, School of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, USA.
| | - Guilherme G Verocai
- Department of Veterinary Pathobiology, School of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, USA.
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Bastos RG, Capelli-Peixoto J, Laughery JM, Suarez CE, Ueti MW. Vaccination with an in vitro culture attenuated Babesia bovis strain safely protects highly susceptible adult cattle against acute bovine babesiosis. Front Immunol 2023; 14:1219913. [PMID: 37583702 PMCID: PMC10424928 DOI: 10.3389/fimmu.2023.1219913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 07/07/2023] [Indexed: 08/17/2023] Open
Abstract
Introduction Live in vivo attenuated Babesia bovis vaccines produced by sequential passages in splenectomized calves have historically been used to control acute bovine babesiosis in endemic areas worldwide. However, several constraints prevent the widespread use of these vaccines, including the need for several splenectomized calves to produce vaccine batches, and potential inconsistent parasite attenuation, which contraindicates their use for highly Babesia-susceptible adult cattle. Thus, the use of vaccines based on well-defined in vitro culture attenuated B. bovis strains emerges as a more sustainable and efficient alternative. Previous work demonstrated that the culture attenuated strain Att-S74-T3Bo is non-tick transmissible and able to safely protect calves against needle challenge with a B. bovis virulent strain. Methods and results Herein we evaluated safety and efficacy of Att-S74-T3Bo in preventing acute babesiosis in adult (>1.5 year of age) cattle. Results demonstrated that Att-S74-T3Bo vaccination of adult animals (n=5) induced self-limiting signs of acute infection and protected the vaccinated animals against challenge with the homologous virulent B. bovis strain Vir-S74-T3Bo. Att-S74-T3Bo-vaccinated adult cattle developed significant (P<0.05) monocytosis, with concomitant neutropenia and CD4+ leukopenia, in peripheral blood early after vaccination. Also, vaccinated animals developed a specific signature of pro- and anti-inflammatory cytokine expression in peripheral blood and significant levels of IgM, total IgG, IgG1, and IgG2 against the B. bovis immunodominant antigen RAP-1 CT. Strikingly, none of the vaccinated animals showed any signs of acute babesiosis after challenge with Vir-S74-T3Bo. In contrast, control adult cattle (n=5) showed pathognomonic symptoms of acute babesiosis, and significant decrease (P<0.05) in lymphocytes, monocytes, and neutrophils, starting on day 7 post-challenge. All control animals developed severe acute disease and were euthanized on days 10 through 12 days post-challenge. Discussion and conclusion Evidence from this study indicates that Att-S74-T3Bo safely protects highly susceptible adult cattle against challenge with a homologous virulent strain of B. bovis. In conclusion, Att-S74-T3Bo may be considered as a potential efficient and sustainable attenuated candidate vaccine strain to control acute bovine babesiosis in highly susceptible adult cattle. Future studies should focus on increasing the number of animals vaccinated, duration of immunity, and efficacy of this attenuated strain against heterologous virulent parasite strains.
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Affiliation(s)
- Reginaldo G. Bastos
- Animal Disease Research Unit, United States Department of Agricultural - Agricultural Research Service, Pullman, WA, United States
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA, United States
| | - Janaina Capelli-Peixoto
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA, United States
| | - Jacob M. Laughery
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA, United States
| | - Carlos E. Suarez
- Animal Disease Research Unit, United States Department of Agricultural - Agricultural Research Service, Pullman, WA, United States
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA, United States
| | - Massaro W. Ueti
- Animal Disease Research Unit, United States Department of Agricultural - Agricultural Research Service, Pullman, WA, United States
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA, United States
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Montero E, Folgueras M, Rodriguez-Pérez M, Pérez-Ls L, Díaz-Arias J, Meana M, Revuelta B, Haapasalo K, Collazos J, Asensi V, Gonzalez LM. Retrospective study of the epidemiological risk and serological diagnosis of human babesiosis in Asturias, Northwestern Spain. Parasit Vectors 2023; 16:195. [PMID: 37296439 DOI: 10.1186/s13071-023-05817-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Accepted: 05/21/2023] [Indexed: 06/12/2023] Open
Abstract
BACKGROUND Babesiosis is a globally growing tick-borne disease in humans. Severe babesiosis caused by Babesia divergens has been reported in two patients from Asturias (Northwestern Spain), suggesting an undetected risk for the disease. To analyze this risk, we retrospectively evaluated the seroprevalence of babesiosis in the Asturian population from 2015 through 2017, a period covering the intermediate years in which these two severe cases occurred. METHODS Indirect fluorescent assay (IFA) and Western blot (WB) were performed to detect B. divergens IgG antibodies in 120 serum samples from Asturian patients infected with the tick-transmitted spirochete Borrelia burgdorferi sensu lato, a condition that indicates exposure to tick bites. RESULTS This retrospective study confirmed a B. divergens seroprevalence rate of 39.2% according to IFA results. B. divergens incidence was 7.14 cases/100,000 population, exceeding previously reported seroprevalence rates. No differences in epidemiology and risk factors were found between patients infected solely with B. burgdorferi s.l. and those infected with B. burgdorferi s.l. and with IgG antibodies against B. divergens. This last group of patients lived in Central Asturias, had a milder clinical course and, according to WB results, developed different humoral responses against B. divergens. CONCLUSIONS Babesia divergens parasites have circulated for several years in Asturias. Epidemiological evidence of babesiosis makes Asturias an emerging risk area for this zoonosis. Human babesiosis could also be relevant in other Spanish and European regions affected by borreliosis. Hence, the potential risk of babesiosis on human health in Asturias and other European forest regions needs to be addressed by the health authorities.
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Affiliation(s)
- Estrella Montero
- Parasitology Reference and Research Laboratory, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, 28220, Madrid, Spain.
| | - María Folgueras
- Infectious Diseases Unit, Hospital Universitario Central de Asturias, Oviedo University School of Medicine, Oviedo, Spain
| | - Mercedes Rodriguez-Pérez
- Microbiology Service, Hospital Universitario Central de Asturias, Oviedo University School of Medicine, Oviedo, Spain
| | - Laura Pérez-Ls
- Researcher, Group of Translational Research in Infectious Diseases, Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), Oviedo, Spain
| | - Javier Díaz-Arias
- Researcher, Group of Translational Research in Infectious Diseases, Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), Oviedo, Spain
| | - Maria Meana
- Internal Medicine, Hospital Alvarez-Buylla, Mieres, Asturias, Spain
| | - Belén Revuelta
- Parasitology Reference and Research Laboratory, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, 28220, Madrid, Spain
| | - Karita Haapasalo
- Department of Bacteriology and Immunology, Medicum, University of Helsinki, 00014, Helsinki, Finland
| | - Julio Collazos
- Infectious Diseases Unit, Hospital de Galdácano, Vizcaya, Spain
| | - Víctor Asensi
- Infectious Diseases Unit, Hospital Universitario Central de Asturias and Group of Translational Research in Infectious Diseases, Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), Oviedo, Spain
| | - Luis Miguel Gonzalez
- Parasitology Reference and Research Laboratory, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, 28220, Madrid, Spain
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