Why are there several species of Borrelia burgdorferi sensu lato detected in dogs and humans?

Tick-Borne Pathogens, Babesia spp. and Borrelia burgdorferi s.l., in Sled and Companion Dogs from Central and North-Eastern Europe

Ticks are important vectors of numerous pathogens of medical and veterinary significance. The aim of the current study was to determine the prevalence of Babesia spp. and Borrelia burgdorferi s.l. in sled and pet dogs from Central and North-Eastern Europe. Neither Babesia spp. nor Borrelia burgdorferi s.l. infections were detected in sled dogs from seven countries (Poland, Lithuania, Latvia, Estonia, Belarus, Russia and Finland). The DNA of Babesia spp. was detected in 100% of symptomatic and 5.4% of asymptomatic pet dogs from Poland. Similarly, the DNA of Babesia spp. was identified in 82% of symptomatic and 3.8% of asymptomatic pet dogs from Ukraine. The DNA of Borrelia burgdorferi s.l. was detected in 4.4% of pet dogs. Molecular typing confirmed the presence of Babesia canis and Borrelia burgdorferi sensu stricto (s.s.) in selected samples. Four dogs were co-infected by B. canis and Borrelia burgdorferi s.l. Tick-borne pathogens constitute a serious health threat to pet dogs in Central and South-Eastern Europe, but were not observed among sled dogs from the same region of Europe nor in the Baltic countries.

Surveillance and Molecular Identification of Borrelia Species in Ticks Collected at U.S. Army Garrison Humphreys, Republic of Korea, 2018-2019

Tick-borne pathogens are contributing factors for the increased incidence of vector-borne diseases throughout the world, including Lyme borreliosis, one of the most prevalent spirochetes belonging to the Borrelia burgdorferi sensu lato group. The present study focused on the detection of Borrelia species from hard ticks collected at U.S. Army Garrison Humphreys, Republic of Korea (ROK), using molecular and genotypic analyses. Tick-borne disease surveillance was conducted from January to December, 2018-2019. A total of 24,281 ticks (2 genera and 5 species) were collected from road-killed Korean Water deer (KWD) and by tick drag. Haemaphysalis longicornis (92.0%) was the most commonly collected species, followed by Haemaphysalis flava (4.9%), Ixodes nipponensis (3.1%), Haemaphysalis phasiana (0.07%), and Haemaphysalis japonica (<0.01%). The ospA gene sequences of Borrelia afzelii were detected in 12/529 pools of I. nipponensis. Three and one pools were positive for B. afzelii and Borrelia miyamotoi, respectively, using the 16s rRNA gene. None of the pools of Haemaphysalis ticks collected from KWD or by tick drag were positive for Borrelia species. I. nipponensis was collected throughout the year from KWD and from February to November by tick drag, suggesting that they were active throughout the year, and expanding the risk period for acquiring Lyme borreliosis and Borrelia relapsing fever in the ROK. This study assessed disease risk factors associated with the prevalence of Lyme disease in ticks collected from KWD and by tick drag using molecular analysis. These results provide an understanding and awareness into the prevalence and molecular characteristics of Borrelia species in the ROK.

Occurrence of Borrelia burgdorferi Sensu Lato in Ixodes ricinus Ticks with First Identification of Borrelia miyamotoi in Vojvodina, Serbia

Lyme borreliosis is the most common tick-borne infectious disease in Eurasia. Borrelia miyamotoi is the only known relapsing fever Borrelia group spirochete transmitted by Ixodes species. The aim of this study was to investigate the presence of Lyme Borrelia spp. and relapsing fever Borrelia spp. in Ixodes ricinus ticks collected from dogs and the vegetation from different parts of Vojvodina, Serbia. A total of 71 Ixodes ricinus ticks were collected and screened for the presence of Lyme Borrelia spp. group and relapsing fever Borrelia spp. by real-time PCR for the Borrelia flagellin B (flaB) gene followed by DNA sequencing of PCR products. Species identification was verified by PCR of the outer surface protein A (ospA) gene for Lyme Disease Borrelia spp. and by PCR of the glycerophosphodiester phosphodiesterase (glpQ) gene for relapsing fever Borrelia spp. Lyme Borrelia spp. were found in 15/71 (21.13%) of the ticks evaluated and included B. luisitaniae (11.3%), B. afzelii (7%), B. valaisiana (1.4%), and B. garinii (1.4%). Borrelia miyamotoi, from the relapsing fever Borrelia complex, was found, for the first time in Serbia, in one (1.4%) nymph collected from the environment. Co-infections between Borrelia species in ticks were not detected. These results suggest that the dominance of species within B. burgdorferi s.l. complex in I. ricinus ticks may vary over time and in different geographic regions. Further systematic studies of Borrelia species in vectors and reservoir hosts are needed to understand eco-epidemiology of these zoonotic infections and how to prevent human infection in the best way.

Tick-borne Diseases (Borreliosis, Anaplasmosis, Babesiosis) in German and Austrian Dogs: Status quo and Review of Distribution, Transmission, Clinical Findings, Diagnostics and Prophylaxis

Tick-borne diseases (TBD) in dogs have gained in significance in German and Austrian veterinary practices. The widespread European tick species Ixodes ricinus represents an important vector for spirochaetes of the Borrelia burgdorferi sensu lato group and Rickettsiales such as Anaplasma phagocytophilum. The meadow or ornate dog tick (Dermacentor reticulatus) is an important vector for Babesia canis, as is the brown dog tick (Rhipicephalus sanguineus) for Babesia vogeli in the Mediterranean region. The present work covers pathogen transmission by tick vectors, including the mechanisms and the minimum intervals required, in conjunction with possible non-vector-borne transmission routes. It also addresses the incubation periods, pathogenicity and clinical findings associated with each pathogen and genospecies and presents case examples. Current data on prevalence, annual fluctuations and distribution in various pre-selected dog populations (symptomatic versus asymptomatic) in both countries are depicted in maps. Reasons for changes in prevalence (especially of Borrelia) are discussed. Criteria and algorithms for clinical diagnosis and monitoring in dogs, including case history, direct detection (blood smears, molecular detection by species-specific PCR and sequencing) and indirect methods (whole-cell and peptide-based antibody tests), are presented, together with laboratory abnormalities (haematology, clinical chemistry, urine). The role of anti-C6 antibody concentration (ACAC) and its correlation with proteinuria and Lyme nephritis are assessed on the basis of new data. Consideration is also given to the importance of blood smears, PCR and serology in the case of anaplasmosis and babesiosis, and the diagnostic value of combining these methods. The relevance of molecular differentiation of Anaplasma species (A. phagocytophilum versus A. platys) and Babesia spp. (large versus small forms) in cases of serological cross-reaction is emphasized. A summary is given of methods for prophylaxis using acaricide products (collars, spot-on solutions and oral treatments in both countries), vaccination (Borrelia and Babesia vaccines) and imidocarb-based chemoprophylaxis for large Babesia.

Serological Detection of Borrelia burgdorferi among Horses in Korea

Lyme disease is a tick-borne zoonotic infectious disease caused by Borrelia burgdorferi. The present study assessed the infection status of B. burgdorferi among horses reared in Korea using ELISA and PCR. Between 2009 and 2013, blood samples were collected from 727 horses throughout Korea. Data for each animal including age, gender, breed, and region of sample collection were used for epidemiological analysis. Overall, 38 (5.2%; true prevalence: 5.5%) of 727 horses were seropositive by ELISA. There were statistically significant differences according to breed and region (P<0.001) whose differences might be attributed to the ecology of vector ticks and climate conditions. Using 2 nested PCR, none of the samples tested positive for B. burgdorferi. Thus, a positive ELISA result can indicate only that the tested horse was previously exposed to B. burgdorferi, with no certainty over the time of exposure. Since global warming is likely to increase the abundance of ticks in Korea, continuous monitoring of tick-borne diseases in Korean horses is needed.

Occurrence of Borrelia burgdorferi s.l. in different genera of mosquitoes (Culicidae) in Central Europe

Lyme disease or Lyme borreliosis is a vector-borne infectious disease caused by spirochetes of the Borrelia burgdorferi sensu lato complex. Some stages of the borrelial transmission cycle in ticks (transstadial, feeding and co-feeding) can potentially occur also in insects, particularly in mosquitoes. In the present study, adult as well as larval mosquitoes were collected at 42 different geographical locations throughout Germany. This is the first study, in which German mosquitoes were analyzed for the presence of Borrelia spp. Targeting two specific borrelial genes, flaB and ospA encoding for the subunit B of flagellin and the outer surface protein A, the results show that DNA of Borrelia afzelii, Borrelia bavariensis and Borrelia garinii could be detected in ten Culicidae species comprising four distinct genera (Aedes, Culiseta, Culex, and Ochlerotatus). Positive samples also include adult specimens raised in the laboratory from wild-caught larvae indicating that transstadial and/or transovarial transmission might occur within a given mosquito population.

Prevalence of select vector-borne pathogens in stray and client-owned dogs from Algiers

Data on the prevalence of vector-borne diseases agents infecting canines in Algeria is currently lacking. The purpose of this study is to assess by serological and molecular methods the prevalence of select arthropod borne-bacterial infections in client-owned and stray dogs. Antibodies to Anaplasma phagocytophilum were the most prevalent at 47.7%, followed by Borrelia burgdorferi s.l. at 37.6%, Ehrlichia canis at 30.0%, Bartonella henselae at 32.4% and Bartonella vinsonii subsp. berkhoffii at 27%. Seroprevalence was statistically significantly higher in stray dogs than those owned by clients. Seropositivity was not associated with health status, except for E. canis. Molecular evaluation indicates that 17.8% of the 213 analyzed dogs were positive for Ehrlichia and Anaplasma with a prevalence of 4.2% for E. canis, 14.1% for Anaplama platys and 0% for A. phagocytophilum. Seven (7.1%) of the tested dogs were positive for Bartonella spp. with two characterized as Bartonella rochalimae, four as B. henselae and one as B.v. subsp. berkhoffii.