Climate change: A driver of increasing vector-borne disease transmission in non-endemic areas.

In this Perspective, Shlomit Paz discusses the link between climate change and transmission of vector-borne diseases in non-endemic areas.

Pranchas para o Diagnóstico Microscópico da Doença de Chagas

As pranchas para o diagnósbco parasitológico da doença de Chagas (DC) servem como guia para laboratoristas e técnicos de campo responsáveis pelo diagnósbco parasitológico da malária que, de forma integrada, sejam capazes de idenbficar os parasitas responsáveis pela doença de Chagas, através de imagens observadas no microscópio ópbco. Este material também pode ser útil a professores e alunos de disciplinas correlatas. As pranchas mostram imagens de fotos coloridas capturadas na observação de lâminas de sangue coradas e preparadas pelos métodos de esfregaço, gota espessa e “esfregota”. Inclui texto explicabvo sobre o Trypanosoma cruzi, agente ebológico da doença, incluindo descrições e instruções sobre o preparo e procedimentos para o exame de lâminas nos diferentes métodos de coloração (Giemsa e panóbco), bem como do uso de soluções tampão; inclui ainda imagens de outros parasitos que podem ser observados no exame da lâmina e outros elementos celulares observados no sangue, como contaminantes comuns em esfregaços de sangue periférico; e também boas prábcas de biossegurança para o manuseio de amostras de sangue. Para facilitar a consulta, as pranchas e o texto que as acompanham estão organizados seguindo a robna usual de um laboratório. São incluídas imagens de Trypanosoma cruzi, T. rangeli, Wuchereria bancrofti, Mansonella sp, Plasmodium spp. e de elementos figurados, que podem estar presentes na amostra coletada. As imagens de T. cruzi e T. rangeli, foram adquiridas a parbr de lâminas confeccionadas com material de sangue de paciente com DC e de material semeado e manbdo em cultura oriundo de sangue humano e conteúdo intesbnal de triatomíneos.

The prevalence of selected vector-borne diseases in dromedary camels (Camelus dromedarius) in the United Arab Emirates.

Vector-borne diseases (VBDs) affecting dromedary camels (Camelus dromedarius) have considerable importance in the United Arab Emirates (UAE) because of the consequences associated with production decline and economic losses. Our study aimed to determine the prevalence of selected VBDs in camels in the UAE and identify risk factors. This research is currently affected by the low number of epidemiological molecular surveys addressing this issue. Blood samples were obtained from 425 dromedary camels from different locations across the UAE. Whole genomic DNA was isolated, and PCR screening was done to detect piroplasmids (Babesia/Theileria spp.), Trypanosoma spp., and Anaplasmataceae spp. (Anaplasma, Ehrlichia, Neorickettsia and Wolbachia spp.). Amplicons were sequenced, and phylogenetic trees were constructed. Trypanosoma sequences were identified as T. brucei evansi, whereas Anaplasmataceae sequences were identified as A. platys-like. All camels were negative for Babesia/Theileria spp. (0%); however, 18 camels were positive for T. b. evansi (4%) and 52 were positive for A. platys-like (12%). Mixed infection with T. b. evansi and A. platys-like was found in one camel. Statistical analyses revealed that camels with a brown coat colour were significantly more prone to acquire the A. platys-like strain compared with those having a clearer coat. A similar finding was observed when comparing urban moving camels with desert indoor and urban indoor camels. Continuous disease surveillance is required to ensure and maintain the good health status of the camels in the UAE. Nonetheless, the risk of disease outbreak remains if the misuse of drugs continues.

Risk perception about communicable and vector borne diseases among international travellers to Pakistan: A cross sectional study.

With the rise in air travel, the risk of diseases travelling from one geographical area to another has also increased. Relatively little is known about how travellers know and perceive the health risks associated with travel and how they adopt preventive measures before and while travelling abroad. The objective of this study is to determine the risk perception about communicable and vector-borne diseases among international travellers arriving from different countries and to find any association between the level of risk perception and independent variables. A cross-sectional study was conducted with 426 participants enrolled through convenient sampling technique. An already validated questionnaire was used to collect information. Chi square test was applied to ascertain any significant association between dependent and independent variables. Out of 426 respondents, only 226 (53%) had a high risk perception, whereas 220 (47%) had a low risk perception. A significant association was noted between the level of risk perception and gender (x2=20.9, p=0.000), level of education (x2=42.9, p=0.000), nationality (x2=7.5, p= 0.006) and region of arrival of the passengers (x2=26.2, p= 0.000). The results of the study revealed that 220 (47%) of the travellers had a low risk perception that may lead to an increase in the burden on healthcare system in Pakistan as well as exporting any new disease from Pakistan to other parts of the world where it does not already exist.

Servicio Autónomo Centro Amazónico de Investigación y Control de Enfermedades Tropicales Simón Bolívar (CAICET)

Ente adscrito al Ministerio del Poder Popular para la Salud cuya misión es desarrollar investigaciones en las diversas ramas de las ciencias biomédicas, ambientales y socioantropológicas de las enfermedades tropicales y sus consecuencias, para la producción de conocimientos, desarrollo de tecnologías y prácticas culturalmente aceptadas, prevención y control de enfermedades endémicas, así como la formación de recursos humanos bajo los principios de universalidad, equidad, solidaridad y respeto a la biodiversidad cultural y ambiental, con capacidad de elevar la calidad de vida de la población de la región sur del país, especialmente de las poblaciones indígenas

Assessing Environmental Risks during the Drug Development Process for Parasitic Vector-Borne Diseases: A Critical Reflection.

Parasitic vector-borne diseases (VBDs) represent nearly 20% of the global burden of infectious diseases. Moreover, the spread of VBDs is enhanced by global travel, urbanization, and climate change. Treatment of VBDs faces challenges due to limitations of existing drugs, as the potential for side effects in nontarget species raises significant environmental concerns. Consequently, considering environmental risks early in drug development processes is critically important. Here, we examine the environmental risk assessment process for veterinary medicinal products in the European Union and identify major gaps in the ecotoxicity data of these drugs. By highlighting the scarcity of ecotoxicological data for commonly used antiparasitic drugs, we stress the urgent need for considering the One Health concept. We advocate for employing predictive tools and nonanimal methodologies such as New Approach Methodologies at early stages of antiparasitic drug research and development. Furthermore, adopting progressive approaches to mitigate ecological risks requires the integration of nonstandard tests that account for real-world complexities and use environmentally relevant exposure scenarios. Such a strategy is vital for a sustainable drug development process as it adheres to the principles of One Health, ultimately contributing to a healthier and more sustainable world.

Manual de microplanificación para la eliminación de la malaria en la Región de las Américas: Versión para personal de campo

Todos los países de la Región de las Américas en los que la malaria es endémica han asumido el reto de eliminar la enfermedad y de poner en marcha intervenciones para orientar sus programas y estrategias de salud en esa dirección. Esta versión simplificada y más operativa del Manual para la estratificación según el riesgo de malaria y la eliminación de focos de transmisión, dirigida al personal de campo, orienta sobre cómo implementar las acciones básicas de eliminación de la malaria. Se propone orientar un cambio en la operación de malaria con la atención centrada en abordar los focos y la organización de la operación en el nivel más local. El documento parte de la necesidad de identificar y definir un ámbito operativo (el foco o microárea) en donde se pone en práctica una intervención programática concreta (DTI-R) que, si bien es estandarizada a nivel nacional, debe ser ante todo guiada por la comprensión de la dinámica de la transmisión a nivel local. Un concepto fundamental del cambio de la estrategia de control por la estrategia de eliminación es reconocer la necesidad de reformular y reajustar constantemente la operación a nivel local en virtud de los cambios que se produzcan en la dinámica de transmisión. La operación contra la malaria no debe entenderse como una tarea que deba realizarse, sino como un problema que ha de resolverse y, para ello, resulta fundamental el uso de información a nivel local y la existencia de un equipo con el interés y la capacitación necesarios para entender el problema y adaptar las soluciones.

Evaluating the long-term impact of COVID-19-associated public health interventions on zoonotic and vector-borne diseases in China: an interrupted time series analysis.

BACKGROUND: The long-term impact of COVID-19-associated public health interventions on zoonotic and vector-borne infectious diseases (ZVBs) remains uncertain. This study sought to examine the changes in ZVBs in China during the COVID-19 pandemic and predict their future trends. METHODS: Monthly incidents of seven ZVBs (Hemorrhagic fever with renal syndrome [HFRS], Rabies, Dengue fever [DF], Human brucellosis [HB], Leptospirosis, Malaria, and Schistosomiasis) were gathered from January 2004 to July 2023. An autoregressive fractionally integrated moving average (ARFIMA) by incorporating the COVID-19-associated public health intervention variables was developed to evaluate the long-term effectiveness of interventions and forecast ZVBs epidemics from August 2023 to December 2025. RESULTS: Over the study period, there were 1,599,647 ZVBs incidents. HFRS and rabies exhibited declining trends, HB showed an upward trajectory, while the others remained relatively stable. The ARFIMA, incorporating a pulse pattern, estimated the average monthly number of changes of - 83 (95% confidence interval [CI] - 353-189) cases, - 3 (95% CI - 33-29) cases, - 468 (95% CI - 1531-597) cases, 2191 (95% CI 1056-3326) cases, 7 (95% CI - 24-38) cases, - 84 (95% CI - 222-55) cases, and - 214 (95% CI - 1036-608) cases for HFRS, rabies, DF, HB, leptospirosis, malaria, and schistosomiasis, respectively, although these changes were not statistically significant besides HB. ARFIMA predicted a decrease in HB cases between August 2023 and December 2025, while indicating a relative plateau for the others. CONCLUSIONS: China's dynamic zero COVID-19 strategy may have exerted a lasting influence on HFRS, rabies, DF, malaria, and schistosomiasis, beyond immediate consequences, but not affect HB and leptospirosis. ARFIMA emerges as a potent tool for intervention analysis, providing valuable insights into the sustained effectiveness of interventions. Consequently, the application of ARFIMA contributes to informed decision-making, the design of effective interventions, and advancements across various fields.

Editorial: Climate Change and the Spread of Vector-Borne Diseases, Including Dengue, Malaria, Lyme Disease, and West Nile Virus Infection.

The major health threats from climate change include increasing temperatures, air pollution, extreme weather events, changes in the spread of infectious diseases, antimicrobial resistance, emerging pathogens, and an increase in vector-borne disease. Between October and December 2023, in 200 medical journal, epidemiologists, clinicians, healthcare policymakers, and journal editors published an emergency call to action to health professionals, the United Nations, and political leaders on climate change and its effects on the ecosystem and human health. Also, in December 2023, the Intergovernmental Panel on Climate Change (IPCC) published its sixth Assessment Report (AR6) that summarizes current knowledge, impacts, and health risks from climate change, as well as suggestions for mitigation and adaptation. For over a decade, the IPCC has reported that the prevalence of vector-borne diseases has increased and highlighted the importance of monitoring dengue, malaria, Lyme disease, West Nile virus infection, and other vector-borne diseases. This editorial aims to provide an update on the association between climate change and the spread of vector-borne diseases and highlights the urgent need for public health and disease prevention and treatment strategies to control the rise in vector-borne diseases.

Disentangling detrimental sand fly-mite interactions in a closed laboratory sand fly colony: implications for vector-borne disease studies and guidelines for overcoming severe mite infestations.

BACKGROUND: Vector sand fly colonies are a critical component of studies aimed at improving the understanding of the neglected tropical disease leishmaniasis and alleviating its global impact. However, among laboratory-colonized arthropod vectors of infectious diseases, the labor-intensive nature of sand fly rearing coupled with the low number of colonies worldwide has generally discouraged the widespread use of sand flies in laboratory settings. Among the different factors associated with the low productivity of sand fly colonies, mite infestations are a significant factor. Sand fly colonies are prone to infestation by mites, and the physical interactions between sand flies and mites and metabolites have a negative impact on sand fly larval development. METHODS: Mites were collected from sand fly larval rearing pots and morphologically identified using taxonomic keys. Upon identification, they were photographed with a scanning electron microscope. Several mite control measures were adopted in two different laboratories, one at the Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases-National Institutes of Health (Rockville, MD, USA), and the other at the University of Calgary (Calgary, AB, Canada). RESULTS: The mite species associated with sand fly colonies in the two laboratories were morphologically identified as Tyrophagus sp. and Stratiolaelaps scimitus. While complete eradication of mites in sand fly colonies is considered unrealistic, drastically reducing their population has been associated with higher sand fly productivity. CONCLUSIONS: We report a case of detrimental interaction between sand flies and Tyrophagus sp. and S. scimitus in a closed laboratory sand fly colony, discuss their impact on sand fly production and provide guidelines for limiting the mite population size in a closed laboratory colony leading to improved sand fly yields.

Vector-borne disease models with Lagrangian approach.

We develop a multi-group and multi-patch model to study the effects of population dispersal on the spatial spread of vector-borne diseases across a heterogeneous environment. The movement of host and/or vector is described by Lagrangian approach in which the origin or identity of each individual stays unchanged regardless of movement. The basic reproduction number [Formula: see text] of the model is defined and the strong connectivity of the host-vector network is succinctly characterized by the residence times matrices of hosts and vectors. Furthermore, the definition and criterion of the strong connectivity of general infectious disease networks are given and applied to establish the global stability of the disease-free equilibrium. The global dynamics of the model system are shown to be entirely determined by its basic reproduction number. We then obtain several biologically meaningful upper and lower bounds on the basic reproduction number which are independent or dependent of the residence times matrices. In particular, the heterogeneous mixing of hosts and vectors in a homogeneous environment always increases the basic reproduction number. There is a substantial difference on the upper bound of [Formula: see text] between Lagrangian and Eulerian modeling approaches. When only host movement between two patches is concerned, the subdivision of hosts (more host groups) can lead to a larger basic reproduction number. In addition, we numerically investigate the dependence of the basic reproduction number and the total number of infected hosts on the residence times matrix of hosts, and compare the impact of different vector control strategies on disease transmission.

Caso importado de malaria por Plasmodium vivax en El Salvador. Un abordaje epidemiológico / Imported Case of Malaria by Plasmodium vivax in El Salvador. An Epidemiological Approach

Presentación del caso. Paciente masculino de origen guatemalteco con historia de fiebre alta de tipo intermitente, mialgias, artralgias, debilidad generalizada, mareo y vómito de contenido gástrico. Fue tratado inicialmente en un hospital privado con diagnóstico de síndrome febril agudo y referido a un hospital de la red nacional con diagnóstico de dengue con signos de alarma, al tercer día de estancia hospitalaria se diagnostica como un caso de malaria importado por Plasmodium vivax. Intervención terapéutica. Se le dio tratamiento antimalárico con cloroquina y primaquina. Evolución clínica. Presentó mejoría clínica y las pruebas de laboratorio de control reportaron resultados negativos para Plasmodium vivax

Case presentation. Male patient of Guatemalan origin with history of intermittent high fever, myalgia, arthralgia, generalized weakness, dizziness, and vomiting of gastric contents. He was initially treated in a private hospital with a diagnosis of acute febrile illness and referred to a national network hospital with a diagnosis of dengue with warning signs. On the third day of hospital stay a diagnosis of an imported malaria case by Plasmodium vivax was presented. Treatment. The patient was given antimalarial treatment consisting of chloroquine and primaquine. Outcome. The patient presented clinical improvement, and control laboratory tests were negative for Plasmodium vivax.

Modeling preferential attraction to infected hosts in vector-borne diseases.

Vector-borne infectious diseases cause more than 700,000 deaths a year and represent an increasing threat to public health worldwide. Strategies to mitigate the spread of vector-borne diseases can benefit from a thorough understanding of all mechanisms that contribute to viral propagation in human. A recent study showed that Aedes mosquitoes (the vectors for dengue and Zika virus, among others) are preferentially attracted to infected hosts. In order to determine the impact of this factor on viral spread, we built a dedicated agent-based model and parameterized it on dengue fever. We then performed a systematic study of how mosquitoes' preferential attraction for infected hosts affects viral load and persistence of the infection. Our results indicate that even small values of preferential attraction have a dramatic effect on the number of infected individuals and the persistence of the infection in the population. Taken together, our results suggests that interventions aimed at decreasing the preferential attraction of vectors for infected hosts can reduce viral transmission and thus can have public health implications.

Species diversity and spatial distribution of mosquitoes (Diptera: Culicidae) from La Isla Amazon Park, Napo Province, Ecuador / Diversidad de especies y distribución espacial de mosquitos (Diptera: Culicidae) del Parque Amazónico La Isla, provincia de Napo, Ecuador

Abstract Introduction: Vector-borne diseases are prevalent in the Amazon and Coastal regions of Ecuador. However, there is a scarcity of mosquito ecology studies in these areas. The most recent list of species reported for the country comprises 8 tribes, 22 genera, and 200 species. Objectives: To document the Culicidae species found in La Isla Amazon Park, Napo, Ecuador, including those with epidemiological significance; and to analyze their composition, abundance, and diversity, focusing on larval habitats during the dry and rainy periods. Methods: We evaluated different larval habitats, considering collection duration as the primary criterion. We used CDC and Shannon traps to collect adult mosquitoes during both rainy and dry periods. To assess sampling effort, we used accumulation curves and non-parametric estimators of species richness, while we employed Hill numbers to determine diversity. Additionally, we used the Berger-Parker and Pielou indices to evaluate species dominance and evenness. We conducted cluster analysis and ANOSIM tests to assess the similarity between habitats and the differences in taxonomic composition between periods. Results: We collected a total of 802 individuals from 15 species and 4 taxonomic units, 5 genera, and 4 tribes. Notably, this may be the first records of Wyeomyia felicia Dyar & Núñez Tovar and Culex derivator Dyar & Knab from Ecuador. Additionally, the presence of Culex dunni Dyar and Psorophora ferox von Humboldt (both recognized as vectors) was correlated with increased rainfall. Conclusions: The abundance of mosquitoes, including potential vector species, increased during the rainy season, indicating a higher risk of pathogen transmission. However, the relationship between rainfall amount and diversity patterns is not well-defined.

Resumen Introducción: Las enfermedades vectoriales son prevalentes en las regiones amazónica y costera de Ecuador. Sin embargo, hay una escasez de estudios de ecología de mosquitos en estas áreas. En el país se ha reportado 8 tribus, 22 géneros y 200 especies. Objetivos: Documentar las especies de Culicidae encontradas en el Parque Amazónico La Isla, Napo, Ecuador, incluyendo aquellas con importancia epidemiológica; y analizar su composición, abundancia y diversidad, enfocándose en los hábitats de las larvas durante los períodos seco y lluvioso. Métodos: Evaluamos diferentes hábitats larvarios, con la duración de la recolecta como criterio. Las trampas CDC y Shannon recolectaron mosquitos adultos durante los períodos seco y lluvioso. Evaluamos la riqueza de especies con curvas de acumulación y estimadores no paramétricos, mientras que determinamos la diversidad con los números de Hill. Además, utilizamos los índices de Berger-Parker y Pielou para evaluar la dominancia y la uniformidad de las especies. Realizamos análisis de conglomerados y la prueba ANOSIM para evaluar la similitud entre hábitats y estaciones, así como las diferencias en la composición taxonómica, respectivamente. Resultados: Recolectamos un total de 802 individuos de 15 especies y 4 unidades taxonómicas, 5 géneros y 4 tribus. Este podría ser el primer registro de Wyeomyia felicia Dyar & Núñez Tovar y Culex derivator Dyar & Knab en Ecuador. Además, la presencia de Culex dunni Dyar y Psorophora ferox von Humboldt (ambos potenciales vectores) se correlacionó con el aumento de las precipitaciones. Conclusiones: El aumento de la abundancia de mosquitos durante el periodo lluvioso indica un mayor riesgo de transmisión de patógenos. Sin embargo, la relación entre la cantidad de precipitaciones y los patrones de diversidad no está bien definida.

Effects of cattle on vector-borne disease risk to humans: A systematic review.

Vector-borne pathogens (VBPs) causing vector-borne diseases (VBDs) can circulate among humans, domestic animals, and wildlife, with cattle in particular serving as an important source of exposure risk to humans. The close associations between humans and cattle can facilitate the transmission of numerous VBPs, impacting public health and economic security. Published studies demonstrate that cattle can influence human exposure risk positively, negatively, or have no effect. There is a critical need to synthesize the information in the scientific literature on this subject, in order to illuminate the various ecological mechanisms that can affect VBP exposure risk in humans. Therefore, the aim of this systematic review was to review the scientific literature, provide a synthesis of the possible effects of cattle on VBP risk to humans, and propose future directions for research. This study was performed according to the PRISMA 2020 extension guidelines for systematic review. After screening 470 peer-reviewed articles published between 1999-2019 using the databases Web of Science Core Collection, PubMed Central, CABI Global Health, and Google Scholar, and utilizing forward and backward search techniques, we identified 127 papers that met inclusion criteria. Results of the systematic review indicate that cattle can be beneficial or harmful to human health with respect to VBDs depending on vector and pathogen ecology and livestock management practices. Cattle can increase risk of exposure to infections spread by tsetse flies and ticks, followed by sandflies and mosquitoes, through a variety of mechanisms. However, cattle can have a protective effect when the vector prefers to feed on cattle instead of humans and when chemical control measures (e.g., acaricides/insecticides), semio-chemicals, and other integrated vector control measures are utilized in the community. We highlight that further research is needed to determine ways in which these mechanisms may be exploited to reduce VBD risk in humans.

Mosquito (Diptera: Culicidae) populations in contrasting areas of the western regions of Burkina Faso: species diversity, abundance and their implications for pathogen transmission.

BACKGROUND: Mosquitoes (Diptera: Culicidae) can have a significant negative impact on human health. The urbanization of natural environments and their conversion for agricultural use, as well as human population growth, may affect mosquito populations and increase the risk of emerging or re-emerging mosquito-borne diseases. We report on the variety and number of adult mosquitoes found in four environments with varying degrees of human impact (rural, urban, rice fields, and forest) located in a savannah zone of West Africa. METHODS: Mosquitoes were collected from two regions (Hauts-Bassins and Sud-Ouest) of Burkina Faso during five periods between August 2019 and June 2021. Sampling sites were grouped according to environment. Mosquitoes were collected using BG-Sentinel traps and double net traps, and Prokopack Aspirators. Statistical analyses were performed using R software version 4.1.2. Logistic regression, using generalised mixed linear models, was used to test the effect of environment on mosquito abundance and diversity. Alpha diversity analysis was also performed, using the vegan package. RESULTS: A total of 10,625 adult mosquitoes were collected, belonging to 33 species and five genera: Culex, Aedes, Anopheles, Mansonia, and Ficalbia. The most dominant species were Culex quinquefasciatus, Anopheles gambiae sensu lato and Aedes aegypti. Alpha diversity was similar in the two regions. Habitat had a significant effect on mosquito species richness, the Shannon index and the Simpson index. The rural environment had the highest species richness (n = 28) followed by the forest environment (n = 24). The highest number of mosquitoes (4977/10,625) was collected in the urban environment. CONCLUSIONS: The species composition of the mosquito populations depended on the type of environment, with fewer species in environments with a high human impact such as urban areas and rice fields. Due to the diversity and abundance of the mosquito vectors, the human populations of all of the environments examined are considered to be at potential risk of mosquito-borne diseases.

Vector-Borne Disease in Wild Mammals Impacted by Urban Expansion and Climate Change.

Ecologies of zoonotic vector-borne diseases may shift with climate and land use change. As many urban-adapted mammals can host ectoparasites and pathogens of human and animal health concern, our goal was to compare patterns of arthropod-borne disease among medium-sized mammals across gradients of rural to urban landscapes in multiple regions of California. DNA of Anaplasma phagocytophilum was found in 1-5% of raccoons, coyotes, and San Joaquin kit foxes; Borrelia burgdorferi in one coyote, rickettsiae in two desert kit foxes, and Yersinia pestis in two coyotes. There was serological evidence of rickettsiae in 14-37% of coyotes, Virginia opossums, and foxes; and A. phagocytophilum in 6-40% of coyotes, raccoons, Virginia opossums, and foxes. Of six flea species, one Ctenocephalides felis from a raccoon was positive for Y. pestis, and Ct. felis and Pulex simulans fleas tested positive for Rickettsia felis and R. senegalensis. A Dermacentor similis tick off a San Joaquin kit fox was PCR-positive for A. phagocytophilum. There were three statistically significant risk factors: risk of A. phagocytophilum PCR-positivity was threefold greater in fall vs the other three seasons; hosts adjacent to urban areas had sevenfold increased A. phagocytophilum seropositivity compared with urban and rural areas; and there was a significant spatial cluster of rickettsiae within greater Los Angeles. Animals in areas where urban and rural habitats interconnect can serve as sentinels during times of change in disease risk.

A retrospective study of vector borne disease prevalence among anemic dogs in North Carolina.

BACKGROUND: Anemia is an important cause of morbidity and mortality in dogs. Further understanding of the prevalence of vector borne diseases (VBD) in anemic dogs is needed. OBJECTIVES: The objective of this retrospective study was to describe the rate of exposure to or infection with VBD among anemic dogs presented to a teaching hospital in North Carolina and to further characterize the anemia in dogs with VBD exposure. ANIMALS: A total of 597 anemic dogs that were concurrently tested for VBD were examined at a referral veterinary hospital between January 2012 and December 2018. METHODS: Retrospective descriptive study. Demographic, clinicopathologic, and VBD testing data were obtained from medical records. RESULTS: Of the 597 anemic dogs examined, 180 (30.15%; 95% CI: 26.49-34.01%) tested positive for one or more VBD. There was no difference in the severity of anemia or the proportion of dogs displaying a regenerative anemia between dogs testing positive and negative for VBD. CONCLUSIONS: A large proportion of anemic dogs from this region test positive for exposure to or infection with VBD. Our study supported the use of PCR and serology run in parallel to maximize the chance of detecting exposure to or infection with VBD compared to either serology or PCR alone. At this time, it is unknown whether infection with VBD contributed to the development of anemia in these patients. However, given the prevalence of VBD exposure in anemic dogs, testing for VBD in anemic patients from this region of the United States is warranted.