Babesiosis in Southeastern, Central and Northeastern Europe: An Emerging and Re-Emerging Tick-Borne Disease of Humans and Animals

Repeated imidocarb treatment failure suggesting emerging resistance of Babesia canis in a new endemic area in north-eastern Germany

Canine babesiosis has been increasingly diagnosed in various regions of Germany such as north-eastern Germany in recent years. A dog with several relapses of Babesia canis infection after treatment with imidocarb is described. A 9-year-old male Magyar Viszla with B. canis infection was referred after two treatments with imidocarb (dosage 2.1 mg/kg SC) because of lethargy, fever and pancytopenia (additional treatments with prednisolone and doxycycline). Merozoites were detected in the blood smear and imidocarb treatment was repeated. Clinical signs, pancytopenia and a positive B. canis PCR occurred after the 3rd (6 mg/kg SC), 4th (7.7 mg/kg SC) and 5th (7.5 mg/kg SC and doxycycline for 4 weeks in addition) imidocarb injection and thorough tick prevention with isoxazoline and permethrin products. 12 days after the 5th injection, the PCR was negative for the first time. The dog was again presented with fever 35 days after the 5th injection. The B. canis PCR was positive and laboratory examination revealed pancytopenia. Treatment with atovaquone/azithromycin for 18 days was performed and no further relapse occurred for 32 weeks. In the case of suspected imidocarb resistance in B. canis infection, treatment with atovaquone/azithromycin can be an alternative.

A global systematic review and meta-analysis on the babesiosis in dogs with special reference to Babesia canis

BACKGROUND

Canine babesiosis is a clinically significant tick-transmitted disease caused by several species of the intraerythrocytic protozoan parasite Babesia, which result in a wide range of clinical manifestations, from mild, transient infection to serious disease and even death.

OBJECTIVES

The current study aimed to estimate the global prevalence and associated risk factors of Babesia in dogs.

METHODS

Multiple databases (PubMed, Scopus, ProQuest, Web of Science and Google Scholar) were searched for relevant literature published from January 2000 up to December 2022. The statistical analyses were performed based on the R software (version 3.6) meta-package.

RESULTS

Out of 23,864 publications, 229 studies met the inclusion criteria. The pooled prevalence of canine babesiosis was 0.120 (95% CI; 0.097-0.146). The highest pooled prevalence was found in Europe (0.207, 95% CI; 0.097-0.344). Among several species, Babesia canis was the most prevalent parasite (0.216, 95% CI; 0.056-0.441). The highest pooled prevalence of Babesia in dogs was observed in the summer season (0.097, 95% CI; 0.040-0.174).

CONCLUSIONS

Regular screening and appropriate control strategies are recommended for the prevention of transmission of tick-borne disease transmission among dogs.

How to Detect Antibodies Against Babesia divergens in Human Blood Samples

Background

Today only indirect fluorescent antibody assays (IFAs) are commercially available to detect antibodies against Babesia divergens in humans. IFA is subjective and requires highly experienced staff. We have therefore developed an enzyme-linked immunosorbent assay (ELISA)-based method for measuring anti-B. divergens immunoglobulin G antibodies in human blood samples.

Methods

Crude merozoite extract from in vitro cultures of a new B. divergens isolate was used in ELISA to detect antibodies in different sets of samples: Borrelia burgdorferi-positive samples, healthy individuals, tick-bitten individuals including follow-up samples 3 months later, positive control samples from patients with an active Babesia infection, and samples from malaria-endemic regions. As a reference, IFA was used to detect antibodies in the tick-bitten samples. Western blot was used to evaluate reactions against specific bands in extracts with/without parasites.

Results

Using IFA as the reference method, the sensitivity and specificity of the ELISA were 86% (12/14) and 100% (52/52). There was a very high correlation (r = -0.84; P = .0004) between IFA dilution factors and ELISA absorbances among the samples classified as positive. Five percent of the B. burgdorferi-positive samples were judged as weakly positive and 5% as strongly positive in our ELISA. Western blot showed that the immunodominant antigens (∼120 kDa) were from merozoites and not from erythrocytes.

Conclusions

This ELISA can detect antibodies directed against B. divergens, and it can be a useful and easy assay to handle compared with IFA. The ELISA can also measure high and low levels of antibodies, which could give insight into the recency of a B. divergens infection.

Ixodid ticks and zoonotic tick-borne pathogens of the Western Balkans

Ixodid ticks are distributed across all countries of the Western Balkans, with a high diversity of species. Many of these species serve as vectors of pathogens of veterinary and medical importance. Given the scattered data from Western Balkan countries, we have conducted a comprehensive review of available literature, including some historical data, with the aim to compile information about all recorded tick species and associated zoonotic pathogens in this region. Based on the collected data, the tick fauna of the Western Balkans encompasses 32 tick species belonging to five genera: Ixodes, Haemaphysalis, Dermacentor, Rhipicephalus and Hyalomma. A range of pathogens responsible for human diseases has also been documented, including viruses, bacteria and parasites. In this review, we emphasize the necessity for integrated surveillance and reporting, urging authorities to foster research by providing financial support. Additionally, international and interdisciplinary collaborations should be encouraged that include the exchange of expertise, experiences and resources. The present collaborative effort can effectively address gaps in our knowledge of ticks and tick-borne diseases.

Coinfection of Babesia and Borrelia in the Tick Ixodes ricinus-A Neglected Public Health Issue in Europe?

Ixodes ricinus nymphs and adults removed from humans, and larvae and nymphs from birds, have been analysed for infection with Babesia species and Borrelia species previously in separately published studies. Here, we use the same data set to explore the coinfection pattern of Babesia and Borrelia species in the ticks. We also provide an overview of the ecology and potential public health importance in Sweden of I. ricinus infected both with zoonotic Babesia and Borrelia species. Among 1952 nymphs and adult ticks removed from humans, 3.1% were PCR-positive for Babesia spp. Of these Babesia-positive ticks, 43% were simultaneously Borrelia-positive. Among 1046 immatures of I. ricinus removed from birds, 2.5% were Babesia-positive, of which 38% were coinfected with Borrelia species. This study shows that in I. ricinus infesting humans or birds in Sweden, potentially zoonotic Babesia protozoa sometimes co-occur with human-pathogenic Borrelia spp. Diagnostic tests for Babesia spp. infection are rarely performed in Europe, and the medical significance of this pathogen in Europe could be underestimated.

Tick-borne pathogens in questing adults Dermacentor reticulatus from the Eastern European population (north-eastern Poland)

Dermacentor reticulatus is tick species with an expanding geographical range in Europe, which creates the possibility of spreading microorganisms of significant veterinary and medical importance. The study aimed to investigate the prevalence and genetic diversity of Rickettsia spp., Babesia spp., Borrelia spp. and Anaplasma phagocytophilum in adult D. reticulatus ticks from the Eastern European population in the urban and the natural biotopes of north-eastern Poland. Microorganisms were detected by PCR and identified by DNA sequencing. The overall infection rate of at least one of the pathogens was 29.6%. The predominantly was Rickettsia spp. (27.1%) (with R. raoultii-9.1%) followed by Babesia spp. (2.4%) with B. canis (1.5%) as the most frequent. Based on 18S rRNA gene sequence, three B. canis genotypes were revealed. The prevalence of R. raoultii and B. canis was significantly higher in ticks from natural biotopes. The infection rates of B. afzelii and A. phagocytophilum were determined at 0.9% and 0.3%, respectively. Co-infections were detected in 3.8% of infected ticks. In diagnosing tick-borne diseases in humans, tick-borne lymphadenopathy should not be excluded. The prevalence of different genotypes of B. canis suggests differences in the clinical picture of canine babesiosis in the area.

First molecular detection of a novel Babesia species from Haemaphysalis hystricis in Taiwan

Newly recorded ticks and emerging tick-borne pathogens have recently been reported in subtropical and tropical East Asia. In this study, a total of 1,615 ticks (259 Haemaphysalis hystricis, 1334 Rhipicephalus microplus, 19 H. flava, and 3 R. haemaphysaloides) were collected by flagging from vegetation in Taiwan during 2019-2021. All 1,615 captured tick samples tested negative for SFTSV and Borrelia, but 12 of 356 tick samples tested positive for PCR amplification of a fragment of the 18S rRNA gene of Babesia spp., with an infection rate of 3.37 % (12/356) and a minimum infection rate of 0.74 % (12/1,615). Among the 12 detected Babesia spp., 11 were identified as Babesia bigemina in R. microplus, and the other one, detected in H. hystricis, was classified as an unnamed novel Babesia sp. Interestingly, the 18S rRNA sequence from the isolate detected in H. hystricis shared 98.79 % to 99.50 % identity with those of recent isolates from Japan, China and Nigeria. The exact origin of the Babesia species is not known, but the findings highlight the importance of international cooperation and the exchange of information on ticks and tick-borne pathogens. This represents a rare report of a Babesia sp. identified in H. hystricis, a tick species that has been proposed as a novel vector for some Babesia spp. This study supports H. hystricis as a possible vector of Babesia spp.

Tick-borne infections in wolves from an expanding population in Eastern Europe

In Central and Eastern Europe, wolf populations have been increasing over the last two decades, recolonizing areas from which the species had been previously exterminated. As wolves are still recovering after years of persecution by humans, recognizing pathogens infecting this species, including tick-borne infections, is crucial for its conservation. On the other hand the high mobility of wolves and their frequent contacts with humans, dogs, and other domestic species make them a potentially important zoonotic reservoir. In this paper, we used molecular methods to determine the prevalence of tick-borne pathogens in the following genera: Anaplasma, Babesia, Bartonella, Borrelia, and Rickettsia in 50 free-ranging wolves from Poland. We detected Babesia canis in the blood of nine individuals (prevalence 9/50=18 %). The obtained sequence showed the highest similarity to B. canis isolated from dogs and ticks, and all infected individuals originated from regions endemic to the ornate tick, Dermacentor reticulatus. Anaplasma phagocytophilum was found in tissue from one individual (1/50=2 %), and the sequence was assigned to the zoonotic ecotype I.

Hazard potential of Swiss Ixodes ricinus ticks: Virome composition and presence of selected bacterial and protozoan pathogens

Ticks play an important role in transmitting many different emerging zoonotic pathogens that pose a significant threat to human and animal health. In Switzerland and abroad, the number of tick-borne diseases, in particular tick-borne encephalitis (TBE), has been increasing over the last few years. Thus, it remains essential to investigate the pathogen spectrum of ticks to rapidly detect emerging pathogens and initiate the necessary measures. To assess the risk of tick-borne diseases in different regions of Switzerland, we collected a total of 10'286 ticks from rural and urban areas in ten cantons in 2021 and 2022. Ticks were pooled according to species, developmental stage, gender, and collection site, and analyzed using next generation sequencing (NGS) and quantitative polymerase chain reaction (qPCR). The metagenomic analysis revealed for the first time the presence of Alongshan virus (ALSV) in Swiss ticks. Interestingly, the pool-prevalence of ALSV was higher than that of tick-borne encephalitis virus (TBEV). Furthermore, several TBEV foci have been identified and pool prevalence of selected non-viral pathogens determined.

Current Status and Challenges Associated with Tick-Borne Pathogens and Diseases: Where Do We Stand?

Lyme Borreliosis (LB), caused by Borrelia burgdorferi sensu lato (s [...].

Recombinant protein immunoblots for differential diagnosis of tick-borne relapsing fever and Lyme disease

Lyme disease (LD) is caused by a group of tick-borne bacteria of the genus Borrelia termed Lyme disease Borreliae (LDB). The detection of serum antibodies to specific LDB antigens is widely used to support diagnosis of LD. Recent findings highlight a need for serological tests that can differentiate LD from tick-borne relapsing fever (TBRF) caused by a separate group of Borrelia species termed relapsing fever Borreliae. This is because LD and TBRF share some clinical symptoms and can occur in overlapping locations. The development of serological tests for TBRF is at an early stage compared with LD. This article reviews the application of line immunoblots (IBs), where recombinant proteins applied as lines on nitrocellulose membrane strips are used to detect antibodies in patient sera, for the diagnosis and differentiation of LD and TBRF.

Molecular detection of pathogens from ticks collected from dogs and cats at veterinary clinics in Finland

BACKGROUND

Ticks carry microbes, some of which are pathogenic for humans and animals. To assess this One Health challenge, 342 ticks were collected from pet dogs and cats at 10 veterinary clinics in Finland as part of the European project "Protect Our Future Too".

METHODS

The tick species were identified, and ticks were screened with quantitative PCR (qPCR) for tick-borne pathogens, including Borrelia burgdorferi sensu lato, Borrelia miyamotoi, Ehrlichia canis, Anaplasma spp., Candidatus Neoehrlichia mikurensis, tick-borne encephalitis virus (TBEV), and Babesia spp. For comparison, a subset of tick DNA (20 qPCR-positive samples) was analysed with 16S next-generation sequencing (NGS).

RESULTS

Most ticks were Ixodes ricinus (289, 84.5%), followed by Ixodes persulcatus (51, 14.9%). One hybrid tick (I. ricinus/I. persulcatus, 0.3%) and one Rhipicephalus sanguineus tick (0.3%) were identified. We found one or more of the analysed pathogens in 17% (59/342) of the ticks. The most prevalent pathogen was B. burgdorferi s.l. (36, 10.5%), followed by Anaplasma phagocytophilum (12, 3.5%), B. miyamotoi (5, 1.5%), Babesia venatorum (4, 1.2%), and TBEV (1, 0.3%). Candidatus Neoehrlichia mikurensis DNA was amplified from three (0.9%) ticks. Ehrlichia canis was not detected. In the 16S NGS, six samples produced enough reads for the analysis. In these six samples, we confirmed all the positive qPCR findings of Borrelia spp. and Ca. N. mikurensis.

CONCLUSIONS

The high prevalence of pathogenic microorganisms in the ticks of this study emphasizes the importance of awareness of ticks and tick-borne diseases and prevention. Furthermore, the results show that veterinary surveillance can facilitate early detection of tick-borne pathogens and new tick species and draw attention to possible co-infections that should be considered both in symptomatic humans and animals after tick bites.

Canine Babesiosis Caused by Large Babesia Species: Global Prevalence and Risk Factors-A Review

Canine babesiosis is a disease caused by protozoan pathogens belonging to the genus Babesia. Four species of large Babesia cause canine babesiosis (B. canis, B. rossi, B. vogeli, and the informally named B. coco). Although canine babesiosis has a worldwide distribution, different species occur in specific regions: B. rossi in sub-Saharan Africa, B. canis in Europe and Asia, and B. coco in the Eastern Atlantic United States, while B. vogeli occurs in Africa, southern parts of Europe and Asia, northern Australia, southern regions of North America, and in South America. B. vogeli is the most prevalent large Babesia species globally. This results from its wide range of monotropic vector species, the mild or subclinical nature of infections, and likely the longest evolutionary association with dogs. The most important risk factors for infection by large Babesia spp. include living in rural areas, kennels or animal shelters, or regions endemic for the infection, the season of the year (which is associated with increased tick activity), infestation with ticks, and lack of treatment with acaricides.

First molecular detection of Babesia vulpes and Babesia capreoli in wild boars from southern Italy

Introduction

Following the increase of wild boar (Sus scrofa) populations in Europe, a potential risk of emerging infections by vector-borne pathogens may occur. Despite this, the circulation of piroplasmid species in these ungulates is still a neglected topic, particularly in the Mediterranean basin. Therefore, this study aimed to investigate the presence of Babesia/Theileria spp. in wild boars from southern Italy to assess the epidemiological role of these ungulates in the circulation of piroplasmids.

Methods

By using a citizen science approach among hunters and veterinarians, wild boar spleen samples were collected in the Campania region (southern Italy) between 2016 and 2022. A combined semi-nested PCR/sequencing analysis targeting the V4 hyper-variable region of 18S rRNA was run to detect Babesia/Theileria spp. DNA.

Results

Out of 243 boars, 15 (i.e., 6.2, 95% CI: 3.4-9.9) tested positive to Babesia/Theileria spp., Babesia vulpes (n = 13, 5.3, 95% CI: 3.1-8.9) the most prevalent, followed by Babesia capreoli (n = 2, 0.8, 95% CI: 0.2-2.9). Three different B. vulpes sequence types were identified (i.e., ST1, ST2, ST3), with the most representative as ST1 (60%), and a single B. capreoli sequence type. No statistically significant difference (p > 0.05) were found between the presence of the pathogens and boar age, sex, province and sample collection year.

Discussion

Data demonstrate for the first time the occurrence of B. vulpes and B. capreoli in wild boars, which may play a role in the biological cycle of piroplasmids. We emphasize the importance of monitoring these ungulates to prevent potential foci of infection. The engagement of hunters in epidemiological scientifically based surveys can constitute a technically sound control strategy of piroplasmids in a One Health perspective.

Molecular Screening of Blood Donors for Babesia in Tyrol, Austria

Introduction

Babesia is a tick-borne intraerythrocytic parasite that is globally ubiquitous, yet understudied. Several species of Babesia have been shown to be transfusion-transmissible. Babesia has been reported in blood donors, animals, and ticks in the Tyrol (Western Austria), and regional cases of human babesiosis have been described. We sought to characterize the risk of Babesia to the local blood supply.

Methods

Prospective molecular testing was performed on blood donors who presented to regional, mobile blood collection drives in the Tyrol, Austria (27 May to October 4, 2021). Testing was conducted using the cobas® Babesia assay (Roche Molecular Systems, Inc.), a commercial PCR assay approved for blood donor screening that is capable of detecting the 4 primary species causing human babesiosis (i.e., B. microti, B. divergens, B. duncani, and B. venatorum). A confirmatory algorithm to manage initial PCR-reactive samples was developed, as were procedures for donor and product management.

Results

A total of 7,972 donors were enrolled and screened; 4,311 (54.1%) were male, with a median age of 47 years (IQR = 34-55). No positive cases of Babesia were detected, corresponding with an overall prevalence of 0.00% (95% CI: 0.00%, 0.05%).

Discussion

The findings suggest that the prevalence of Babesia is low in Austrian blood donors residing in the Tyrol, even during months of peak tick exposure. Although one cannot conclude the absence of Babesia in this population given the limited sample size, the findings suggest that the regional risk of transfusion-transmitted babesiosis is low.

Babesiosis concurrent with multiple abscesses from Staphylococcus aureus infection: A case report

Background

Babesiosis is a tick-borne illness. These patients may have signs of a systemic inflammatory response, but abscess formation is unusual. Multiple abscesses in a patient with confirmed babesiosis is very rare, so concurrent infection by another pathogen should be considered.

Case presentation

We report a 42-year-old male patient who had fever, chills, joint pain, abdominal pain, and altered mental status after a possible tick bite on his right foot while fishing in a river. The laboratory tests, including a blood smear, suggested babesiosis. Imaging studies showed multiple brain and spleen abscesses due to Staphylococcus aureus based on the results of a blood culture and next-generation sequencing. The patient eventually recovered after treatment with azithromycin, fosfomycin, and vancomycin.

Conclusion

Concurrent bacterial infection can occur in a patient with babesiosis. Additional tests should be performed when a babesiosis patient presents with signs inconsistent with Babesia infection. Prompt and appropriate treatment is necessary and may be life-saving for these patients.

Field efficacy of fluralaner (Bravecto® chewable tablets) for preventing Babesia canis infection transmitted by Dermacentor reticulatus ticks to dogs

BACKGROUND

The isoxazoline fluralaner is effective for prevention of Babesia canis transmission from infected Dermacentor reticulatus ticks to dogs for 84 days in a controlled environment. This study was designed to evaluate the effectiveness of fluralaner chewable tablets for sustained prevention of B. canis infection of dogs in endemic areas under natural conditions.

METHODS

In Europe, privately owned, clinically healthy pet dogs were enrolled and randomized either to receive fluralaner at 25-56 mg/kg (Bravecto® chewable tablets) on days 0 and 84, or to remain untreated during the D. reticulatus season. Blood samples were collected to evaluate B. canis exposure: on days 0 and 21 (exposure before day 0), during the study and at the end of the tick season (dogs suspected of having become infected after day 0). Efficacy was determined by the percentage reduction in B. canis transmission risk based on the difference in B. canis-positive tests in fluralaner-treated dogs compared with untreated dogs. In addition, ticks collected at monthly intervals throughout the study were identified to species level and females tested for B. canis DNA.

RESULTS

A total of 152 dogs were enrolled in the study, although nine dogs were excluded because they tested positive for B. canis DNA or antibodies within 21 days after enrollment. During the study period, no fluralaner-treated dog became positive for B. canis, resulting in calculated efficacy of 100%. However, babesiosis infection was diagnosed in five untreated control dogs (Fisher's exact test, left-sided, P = 0.0312). Tick analyses revealed that one sample collected in Hungary was infected with B. canis.

CONCLUSION

Oral administration of Bravecto chewable tablets at the recommended dosage to dogs completely prevented B. canis transmission under field conditions in an endemic area for 12 weeks.

Plasma pharmacokinetics of tigolaner, emodepside, and praziquantel following topical administration of a combination product (Felpreva®) and of intravenous administration of the individual active ingredients in cats

Felpreva® for cats contains the new acaricidal/insecticidal active ingredient tigolaner in a fixed combination with the nematocidal and cestocidal compounds emodepside and praziquantel, respectively. The plasma pharmacokinetics of tigolaner, emodepside, and praziquantel were evaluated in clinically healthy cats following topical (spot-on) treatment as fixed combination Felpreva®. For the determination of bioavailability intravenous administration of single active ingredients was also performed. After a single topical administration of Felpreva® using the target dose volume of 0.148 ​ml/kg to cats, tigolaner reached mean peak concentrations of 1352 ​μg/l with a T_max of 12 days and a mean half-life of 24 days. Simulation of repetitive topical administration every 91 days indicates only a low risk of accumulation after reaching steady state within two to three administrations. The volume of distribution calculated after intravenous dosing was 4 ​l/kg and plasma clearance was low with 0.005 ​l/h/kg. Overall plasma exposure was 1566 ​mg∗h/l after topical administration, providing an absolute bioavailability of 57%. Tigolaner was mainly cleared via the faeces (54% within 28 days), renal clearance was neglectable (< 0.5% within 28 days). Emodepside and praziquantel showed mean peak concentrations of 44 ​μg/l and 48 ​μg/l (reached after 1.5 days and 5 ​h, respectively). Overall plasma exposures were 20.6 and 3.69 ​mg∗h/l, respectively. The elimination half-life was 14.5 days for emodepside and 10 days for praziquantel after topical administration. After topical administration of Felpreva® using 2.5× and 5× dose multiples an almost proportional increase of plasma exposure was observed for all three active ingredients. With the addition of tigolaner, Felpreva® combines the established pharmacokinetic (PK) characteristics of emodepside and praziquantel contained in Profender® spot-on for cats with the favourable PK of tigolaner suitable for a 3-months protection against fleas and ticks.

Babesia divergens Shows Equal Predilection for Human ABO Blood Types in an In Vitro Erythrocyte Preference Assay

Babesia is spread to humans via ticks or blood transfusions. Severity of Plasmodium falciparum malaria is strongly correlated to the ABO blood group of the patient. Babesia divergens is an intraerythrocytic parasite with many similarities to malaria, but the impact of ABO on the susceptibility to and progression of the infection in humans is unknown. We have now cultured B. divergens in human group A, B and O erythrocytes in vitro and measured rates of multiplication. The predilection for the different erythrocyte types was also determined using an in vitro erythrocyte preference assay when the parasites were grown in group A, B or O erythrocytes over time and then offered to invade differently stained erythrocytes of all the blood types at the same time. The results showed no difference in multiplication rates for the different blood types, and the parasite exhibited no obvious morphological differences in the different blood types. When cultured first in one blood type and then offered to grow in the others, the preference assay showed that there was no difference between the A, B or O blood groups. In conclusion, this indicates that individuals of the different ABO blood types are likely to be equally susceptible to B. divergens infections.

Year-round tick exposure of dogs and cats in Germany and Austria: results from a tick collection study

BACKGROUND

Ticks and tick-borne diseases play a major role in companion animal health. Additionally, the European tick fauna is changing, for instance due to the spread of Dermacentor reticulatus, displaying a higher likelihood of winter activity than Ixodes ricinus. Therefore, we investigated current tick infestations in dogs and cats in Germany and in parts of Austria and the seasonal infestation risk.

METHODS

Overall, 219 veterinary practices were invited to collect ticks from cats and dogs on a monthly basis. Ticks were morphologically identified and female I. ricinus specimens were measured to estimate attachment duration.

RESULTS

In total, 19,514 ticks, 17,789 (91.2%) from Germany and 1506 (7.7%) from Austria, were received between March 2020 and October 2021, with 10,287 specimens (52.7%) detached from dogs, 8005 from cats (41.0%) and 1222 from other species (6.3%). In Germany, the most common tick species collected from dogs were I. ricinus (78.0%) and D. reticulatus (18.8%), while cats mainly harboured I. ricinus (91.3%) and I. hexagonus (5.5%) and only few D. reticulatus (0.6%). In Austria, collected I. ricinus reached similar proportions in dogs (90.4%) and cats (95.3%), followed by D. reticulatus in both dogs (5.2%) and cats (1.5%), with I. hexagonus (0.9%) collected only marginally from cats. The average infestation intensity amounted to 1.62 ticks/dog and 1.88 ticks/cat. The single to multiple infestation ratio was 79.1% to 20.9% in dogs and 69.0% to 31.0% in cats, with cats being significantly more often multiple infested than dogs, while the proportion of mixed-species infestations was 2.0% for both dogs and cats. The average attachment duration of female I. ricinus specimens amounted to 78.76 h for dogs and 82.73 h for cats. Furthermore, year-round tick exposure was confirmed, with 108 D. reticulatus and 70 I. ricinus received on average per month during December 2020 to February 2021.

CONCLUSIONS

The study shows a year-round tick infestation risk, with activity of both D. reticulatus and I. ricinus during winter, and confirms the widespread occurrence of D. reticulatus in Germany. Additionally, long average attachment durations and frequent multiple infestations underline the need for adequate year-round tick control, even during the winter months.

Haematological indices and immune response profiles in dogs naturally infected and co-infected with Dirofilaria repens and Babesia canis

Co-infections with Dirofilaria repens and Babesia canis are rarely reported in the literature and there is very limited knowledge of their impact on canine health. Central Poland is endemic for both parasites, posing a risk of co-infections in dogs. To evaluate the impact of co-infection with B. canis and D. repens on canine health, four groups of dogs were examined: healthy dogs, dogs infected with B. canis, dogs infected with D. repens and dogs co-infected with both species. Blood parameters indicative of anaemia, kidney and liver damage were analysed statistically. Additionally, expression levels of immune response genes were quantified and compared, to define the type of immune response typically encountered in single- and co-infections. In dogs infected with D. repens, no major alterations in blood parameters were observed. Dogs infected with B. canis suffered from anaemia, kidney and liver insufficiency. In contrast, dogs co-infected with D. repens and B. canis showed milder alternation in blood biochemical parameters associated with liver (ALP activity) and kidney (serum urea and creatinine levels) dysfunction, compared to dogs infected only with B. canis. The expression of genes associated with cellular (Th1-mediated) (STAT4 and INF-γ), humoral (Th2-mediated) (STAT6, GATA3, SOCS3, IL-13) and regulatory (IL-10) responses was quantified. For this analysis, dogs infected with B. canis were divided into two groups-'Babesia 1' (mild babesiosis), 'Babesia 2' (severe babesiosis). All the tested factors, except INF-γ, were found to be expressed in dogs infected with D. repens. In 'Babesia 1' dogs, expression of GATA3 was highest, while in 'Babesia 2'-INF-γ and SOCS3 dominated. IL-13 expression was predominant in dogs infected with D. repens, and STAT6 and IL-10 predominated in dogs with co-infections.

Canine babesiosis in Austria in the 21st century - A review of cases

A retrospective study on 699 cases of canine babesiosis presented to veterinary clinics in eastern Austria were evaluated for the location where infection had presumably taken place. Of these, 542 (77.54%) had acquired the infection in Austria, while the majority of non-autochthonous cases came from neighboring countries, most notable Hungary. Both groups were recorded primarily in Vienna, eastern Lower Austria and Burgenland, but cases from the southern (Styria, Carinthia) and western (Upper Austria, Tyrol, Salzburg) provinces of the country were also recorded. Records were made all year round, with most cases in spring (46.6%) and fall (48.4%). The annual cases ranged from four to 58 (mean: 31.8) with large fluctuations and no visible trend for an in- or decrease. The tick vector of Babesia canis, Dermacentor reticulatus, is present in Austria but displays a very patchy distribution, and its occurrence and activity are not readily foretold, which might be a reason why its presumably increasing density in Europe is not reflected by increased incidences of canine babesiosis. Another factor that may influence the numbers of cases per year could be the application (or non-application) of acaricidal or repellent compounds. A limitation of this study is that bias is exerted by the location of the participating clinics, and by the unknown rate of infections that does not induce clinical symptoms and is likely not presented in veterinary practices and clinics. The data, however, clearly show that at least the lowlands of Austria are endemic for B. canis, and appropriate tick control must be advised all year round.

The First Records of Canine Babesiosis in Dogs from Dermacentor reticulatus-Free Zone in Poland

Tick-borne microorganisms belong to important etiological agents of many infectious diseases affecting humans and animals. Among them, there are haemoprotozoans of the Babesia genus, which infect erythrocytes of a host and may cause many clinical symptoms. Canine babesiosis is an emerging tick-borne disease in Southern and Central Europe. In this study, we report two cases of symptomatic canine babesiosis caused by Babesia canis in domestic dogs from the Silesian Voivodeship, Poland, as well as the presence of Dermacentor reticulatus ticks detected on one of the Babesia-infected dogs (D. reticulatus-free zone). The molecular analysis confirmed the presence of Babesia canis in the dogs’ blood, and the sequencing analysis showed that the obtained sequence is 100% identical to the sequence of Babesia canis isolate 3469 (sequence ID: KX712122.1). Our findings should raise awareness of B. canis infection among dog owners and veterinarians in the region where B. canis was not previously reported in residential, non-traveling dogs, as well as ensuring that adequate diagnostic methods are available.

Biosynthesis and extrinsic toxicity of copper oxide nanoparticles against cattle parasites: An eco-friendly approach

Plant extracts' ability to collect metals and decrease metal ions makes them a superior candidate for the biosynthesis of nanoparticles; hence, they are referred to as bio-nano factories since both living and dead dried biomass are employed to produce metallic nanoparticles. The antiparasitic activity of biosynthesized copper oxide nanoparticles (CuO NPs) was examined against cow tick larvae (Rhipicephalus microplus, Haemaphysalis bispinosa, and Hippobosca maculata). These parasitic larvae were treated with various concentrations of methanolic leaf extract of A. marmelos (MLE-AM) and biosynthesized CuO NPs for 24 h. CuO NPs were synthesized quickly using A. marmelos leaf extract, and nanoparticle synthesis was identified within 15 min. The results from characteristic XRD, FTIR, SEM, EDX, and TEM analyses confirmed the biosynthesis of CuO NPs. The presence of 26-Hydroxycholesterol was discovered as the predominant chemical present in the GC-MS analysis of MLE-AM. The maximum efficacy was observed in biosynthesized CuO NPs against R. microplus larvae, H. bispinosa adults, and Hip. maculata larvae (LC₅₀ = 4.30, 9.50, and 11.13 mg/L; and LC₉₀ = 8.30, 19.57, and 21.65 mg/L; and 6.219, 6.547, and 2.587). Overall, the bio-fabrication of CuO NPs has the potential to develop better and safer antiparasitic control techniques.

Prevalence of Babesia spp. pathogens in the ticks Dermacentor reticulatus and Ixodes ricinus in the UK

The emergence of Babesia pathogens novel to the UK is of growing concern; these include Babesia canis and Babesia caballi. However, a better understanding of changes in the prevalence of endemic Babesia species such as Babesia venatorum and Babesia divergens is also of importance. Here, the prevalence of Babesia pathogens in both Dermacentor reticulatus and Ixodes ricinus ticks was assessed. Dermacentor reticulatus were collected from six sites known to harbour populations of this species in west Wales and southern England. DNA was extracted from 879 individual ticks and subjected to PCR and sequence analysis. Seven Babesia species were detected in 7.5% of the ticks, including B. caballi (0.68%), B. bovis (1.7%), B. microti (1.02%), B. bigemina (0.34%), B. capreoli (0.34%), and one isolate of B. canis (0.34%). Two of the field sites with grazing equines present had ticks that were positive for B. caballi. For I. ricinus, up to 200 nymphs were collected from each of 24 cattle farms in south-west England. Nymphs were divided into 6 pools of 30 from each farm for DNA extraction, PCR, and sequencing. Samples from seven out of the 24 farms tested positive for Babesia, and most were positive for more than one species. Babesia divergens was identified from five farms, and three of these farms had two pooled samples positive for B. divergens, which given the low overall prevalence rate suggests that B. divergens may be highly clustered within the tick population. Most of the remaining positive samples were Babesia venatorum, demonstrating that this zoonotic pathogen is widespread in livestock habitats. The data suggest that B. canis is not yet widely prevalent in established D. reticulatus populations in the UK, but that there is a need to raise awareness of the risk of equine piroplasmosis in areas with endemic D. reticulatus foci, since B. caballi appears more widely established.

Genetic Diversity of Babesia canis Strains in Dogs in Lithuania

Canine babesiosis is an emerging and rapidly expanding tick-borne disease in central and northeast Europe. In the last two decades, the endemic area of Babesia canis has expanded from central Europe to the Baltic region. This study aimed to investigate the genetic diversity of B. canis strains isolated from naturally infected dogs in different regions of Lithuania using PCR-RFLP and sequence analyses based on a partial region of 18S rRNA and Bc28.1 genes. Blood samples from 149 dogs suspected of having babesiosis were collected in Lithuania during 2016–2017. Based on PCR-RFLP profiles and two nucleotide substitutions observed in 18S rRNA gene sequences, three B. canis genotypes were identified in Lithuania—18S rRNA-A, 18S rRNA-B and 18S rRNA-A/B—with the A/B genotype predominating (83.9%). Based on the obtained PCR-RFLP profiles of the Bc28.1 gene, four B. canis genotypes were identified: Bc28.1-B (53.8%), Bc28.1-34 (20.8%), Bc28.1-A (17.9%), and Bc28.1-34/A or B (7.5%). Sequence analysis of the partial Bc28.1 gene revealed eighteen polymorphic sites and thirteen sequence variants among the Lithuanian samples. The B. canis genotypes obtained were detected with varying prevalences in different regions of Lithuania.

High genetic diversity of Babesia canis (Piana & Galli-Valerio, 1895) in a recent local outbreak in Berlin/ Brandenburg, Germany

Canine babesiosis caused by Babesia canis (Piana & Galli-Valerio, 1895) is emerging in new regions in Europe since its vector Dermacentor reticulatus (Fabricius, 1794) is expanding its geographic range. In the Berlin/Brandenburg area in northeast Germany, D. reticulatus is highly abundant but in the past only one autochthonous B. canis infection was reported. Since 2015, autochthonous cases were occasionally diagnosed but numbers increased since autumn 2019. The aim of the study was to genotype autochthonous canine Babesia spp. infections from Berlin/Brandenburg. Between 04/2015 and 01/2022, 46 dogs with acute babesiosis were presented to the small animal clinic (one dog was infected twice resulting in 47 samples). There were 32 dogs that had never left Berlin/Brandenburg and 14 others that had not left the region in the 6 weeks prior to disease onset. PCRs targeting the 18S rRNA and the Bc28.1 merozoite surface antigen were positive in 47 and 42 samples, respectively. Sequencing of cloned PCR products identified all samples as B. canis with 17 18S rRNA and 12 Bc28.1 haplotypes. Based on network analysis for 18S rRNA sequences and a previously described polymorphic dinucleotide, samples were assigned to two distinct clusters. One contained 31 and the other 16 samples. Using network analysis, the Bc28.1 haplotypes could also be separated into two clusters differing by at least five polymorphisms. Analyses of sequences from multiple clones indicated the presence of up to five 18S rRNA and eight Bc28.1 haplotypes and thus high parasite variability in an individual host. The genetic diversity could suggest that the parasites in the region have multiple origins, but diversity in individual dogs and dog populations from endemic regions is unknown. The suitability of both markers for genotyping is questionable due to potential intragenomic diversity for the rRNA and high intergenomic variability for the Bc28.1 marker.

Diversity of Borrelia burgdorferi sensu lato in ticks and small mammals from different habitats

BACKGROUND

Ixodid ticks are important vectors for zoonotic pathogens, with Ixodes ricinus being the most important in Europe. Rodents are hosts of immature life stages of I. ricinus ticks and are considered main reservoirs for tick-borne pathogens, e.g. Borrelia burgdorferi. The aim of this study was to analyse the prevalence as well as genospecies and sequence type (ST) diversity of Borrelia burgdorferi sensu lato in ticks and small mammals from central Germany and to elaborate on the influence of environmental and/or individual host and vector factors on Borrelia prevalence.

METHODS

After species identification, 1167 small mammal skin samples and 1094 ticks from vegetation were screened by B. burgdorferi sensu lato real-time polymerase chain reaction, and positive samples were characterized by multilocus sequence typing. Generalized linear (mixed) models were used to estimate how seasonality, small mammal species/tick life stage and habitat affect individual infection status.

RESULTS

In total, 10 small mammal species and three tick species, Ixodes ricinus, Ixodes inopinatus (both considered members of the I. ricinus complex) and Dermacentor reticulatus, were investigated. Borrelia DNA was detected in eight host species, i.e. the striped field mouse (Apodemus agrarius), the yellow-necked field mouse (Apodemus flavicollis), the wood mouse (Apodemus sylvaticus), the water vole (Arvicola amphibius), the bank vole (Clethrionomys glareolus), the field vole (Microtus agrestis), the common vole (Microtus arvalis), and the common shrew (Sorex araneus). Two species were Borrelia negative, the greater white-toothed shrew (Crocidura russula) and the pygmy shrew (Sorex minutus). The average prevalence was 6.2%, with two genospecies detected, Borrelia afzelii and Borrelia garinii, and at least three STs that had not been previously reported in small mammals. Borrelia prevalence in small mammals did not differ between seasons. Six genospecies of Borrelia-Borrelia afzelii, Borrelia valaisiana, Borrelia garinii, Borrelia lusitaniae, Borrelia spielmanii, and Borrelia burgdorferi sensu stricto-and 25 STs of Borrelia, of which 12 have not been previously described at all and five have not been previously reported in Germany, were detected in 13% of I. ricinus complex ticks. Prevalence was highest in adult females (25.3%) and lowest in nymphs (11.4%). Prevalence was significantly higher in ticks from grassland (16.8%) compared to forests (11.4%).

CONCLUSIONS

The high level of small mammal diversity in this region of Germany seems to be reflected in a wide variety of genospecies and STs of B. burgdorferi.

Fluorescence In Situ Hybridization (FISH) Tests for Identifying Protozoan and Bacterial Pathogens in Infectious Diseases

Diagnosing and treating many infectious diseases depends on correctly identifying the causative pathogen. Characterization of pathogen-specific nucleic acid sequences by PCR is the most sensitive and specific method available for this purpose, although it is restricted to laboratories that have the necessary infrastructure and finance. Microscopy, rapid immunochromatographic tests for antigens, and immunoassays for detecting pathogen-specific antibodies are alternative and useful diagnostic methods with different advantages and disadvantages. Detection of ribosomal RNA molecules in the cytoplasm of bacterial and protozoan pathogens by fluorescence in-situ hybridization (FISH) using sequence-specific fluorescently labelled DNA probes, is cheaper than PCR and requires minimal equipment and infrastructure. A LED light source attached to most laboratory light microscopes can be used in place of a fluorescence microscope with a UV lamp for FISH. A FISH test hybridization can be completed in 30 min at 37 °C and the whole test in less than two hours. FISH tests can therefore be rapidly performed in both well-equipped and poorly-resourced laboratories. Highly sensitive and specific FISH tests for identifying many bacterial and protozoan pathogens that cause disease in humans, livestock and pets are reviewed, with particular reference to parasites causing malaria and babesiosis, and mycobacteria responsible for tuberculosis.