Tick-borne diseases are among the most common vector-borne diseases. These include various infections caused by viruses, bacteria, rickettsiae, spirochetes and protozoa. The aim of our review is to present the relationship between the clinico-epidemiological aspect of some of the emergency tick-borne diseases and their diagnosis, treatment and prevention. We will review three diseases- anaplasmosis, babesiosis and ehrlichiosis. Anaplasmosis and ehrlichiosis are caused by small gram-negative obligate intracellular alphaproteobacteria in the order Rickettsiales, family Anaplasmataceae. The prognosis of disease depends on early diagnosis and proper treatment. The symptoms of anaplasmosis largely overlap with those of ehrlichiosis. Babesiosis is a malaria-like disease that is caused by intraerythrocytic protozoa. Like malaria, the disease proceeds with hemolysis and its severity is determined by the parasitemia. Treatment of babesiosis involves the use of antimalarial agents and antibiotics, most commonly in a combination. Understanding the clinical, epidemiological and laboratory characteristics of tick-borne diseases is crucial for their prevention, diagnosis and treatment.

Babesia microti (B. microti), is a tick-transmitted protozoan parasite that infects red blood cells. It is the primary cause of human babesiosis in the US. It is also considered an emerging pathogen that continues to expand in terms of both numbers of cases and geograpical range. The severity of babesiosis can range from asymptomatic to fatal. Nevertheless, the mechanisms important for resolution of infection versus pathology remain largely unknown. In the current study we used a mouse model to evaluate factors important in protection from reinfection with B. microti following the clearance of a primary infection. Both B cell and CD4 T cell deficient mice failed to completely eliminate parasitemia 36 days post-infection following primary challenge. In the recall mouse model of infection, wild type or specific gene deleted mice were reinfected with the same strain of B. microti parasites 30-36 days after the initital primary infection, and the development of parasitemia was evaluated. Our results show that wild type mice were protected from reinfection with B. microti. In contrast, B cell and CD4 T cell deficient mice were only modestly impaired in their ability to protect against rechallenge as protection was more similar to reinfected wild type mice than naïve mice. However, one reinfected B cell deficient mice developed parasitemia levels similar to those observed in primary infection. Other factors including IFN-γ, inducible nitric oxide synthase (iNOS) and the adaptor protein MyD88 important for signling via IL-18 and IL-1 had no effect on rechallenge. Thus our study shows that infection with B. microti confers at least short term protection against rechallenge with the same parasite strain. Our data show that CD4 T cells make an important contribution to both primary and rechallenge infection with B. microti. They also suggest that antibody might play an important role in protection against reinfection or persistent infection. However, overall our results Our results suggest that no one aspect of the immune system is solely responsible for adequate protection against reinfection with B. microti.

Background: Babesiosis and its tick carriers cause serious problems for cattle and are among the common protozoan blood parasites in Ethiopia. Methods: A cross-sectional survey was conducted from September 2019 to August 2020 to identify babesiosis in cattle and its tick vectors in extensively managed livestock in Dasenech and Salamago District South Omo Ethiopia. A total of 470 blood samples were collected for identification of hemoparasite using a thin blood smear followed by the Giemsa staining method and Packed Cell Volume (PCV) determination for detection of anemia. Results: Accordingly, the overall prevalence of bovine babesiosis in the study districts were 21.7% and Babesia bigemina (15.53%) and B. bovis (6.17%) were identified during this study. Factors such as age, sex, body condition score, season, tick burden, and level of tick Infection were considered as risk factors; yet, the season and level of tick Infection were found significantly associated (p< 0.05) with the occurrence of babesiosis. Besides, the mean PCV value of infected cattle (21.49%) was lower than non-infected animals (28.29%) which shows there was a strong correlation (p=0.0001) between anemia and Babesiosis. The prevalence of tick Infection was 86.17% (405/470) and a total of 8040 ticks adult ticks belonging to four tick genera namely Amblyomma (32.34%), Boophilus (18.51%), Hyalomma (18.94%), and Rhipicephalus (16.38%) were identified and all have a significant role (p< 0.05) on the occurrence of babesiosis in cattle. Conclusion: Bovine babesiosis is an important hemoparasitic protozoan disease of cattle in the study areas. To address and manage the problem, nearby veterinary service systems need to diagnose blood parasites and provide alternatives, especially for tick-borne diseases. Also, it is essential to customize appropriate and integrated tick control measures and tactical treatment of overt bovine babesiosis clinical cases.

Babesia species infect a very wide range of mammal hosts across the globe and zoonotic infections are of growing concern. Several species of the Babesia genus infect dogs and some of these cause significant morbidity and mortality. The Apicomplexan parasite resides within the red cell and infections result in direct damage to the host through intra- and extravascular hemolysis. An exuberant inflammatory response by the host to some species of Babesia parasites also result in significant collateral damage to the host. Canine infections have been the subject of much study as the wellbeing of these companion animals is increasingly threatened by the spread of tick vectors and an increasingly mobile dog population. There are no widely available and effective vaccines and effective treatment can be challenging. Understanding disease pathogenesis underlies the development of new treatments. The varying pathogenicity of the various Babesia parasite species that infect dogs offers an opportunity to explore the molecular basis for the wide range of disease caused by infection with this parasite genus. In this review we focus on what has been reported about the clinical presentation of Babesia infected dogs in an attempt to compare the severity of disease caused by different Babesia species.

Clinical and analytical differences between adult patients monoinfected with Borrelia burgdorferi sensu lato (s.l.) and patients infected with B. burgdorferi s.l. who also had IgG antibodies against Babesia divergens have not been reported so far. Both Lyme disease caused by B. burgdorferi and babesiosis caused by B. divergens, endemic in Asturias, Northwestern Spain, are transmitted by Ixodes tick bites. Clinical, laboratory and other diagnostic tests characteristics (imaging, electro-cardiographic-ECG) of 120 residents of Asturias with confirmed B. burgdorferi s.l. infection, di-agnosed during 2015-2017, of whom 47 (39.2%) had B. divergens IgG antibodies, were retrospec-tively compared. Cardiorespiratory symptoms were reported in 9/47 (19.2%) patients with Lyme disease and B. divergens IgG antibodies compared to 4/73 (5.5%) patients with B. burgdorferi s.l. monoinfection (P=0.02). Dyspnea was recorded in 4/47 (8.5%) patients with Lyme disease and B. divergens IgG antibodies compared to 1/73 (1.4%) monoinfected (P=0.07). In addition ECG atri-oventricular (AV) block, mostly 1st degree, was detected in 5/47 (15.6%) patients with Lyme dis-ease and B. divergens IgG antibodies compared to 1/73 (2.6%) B. burgdorferi s.l. monoinfected (P=0.09). No other clinical, laboratory or other tests differences were observed between B. burgdorferi and B. divergens IgG antibodies carriers and B. burgdorferi monoinfected. We con-cluded that patients with Lyme disease and B. divergens IgG antibodies had more frequent car-diorespiratory symptoms, mainly dyspnea, compared to B. burgdorferi monoinfected patients. These symptoms were unrelated to anemia. ECG AV block, perhaps induced by summative myo-cardial damage due to either infections or B. divergens induced lung microcirculation slow-ing-down, might play a role in the cardiorespiratory dysfunction.

Three patients with multi-year histories of relapsing and remitting Lyme disease and associated co-infections despite extended antibiotic therapy were each given double dose dapsone combination therapy (DDD CT) for a total of 7-8 weeks. At the completion of therapy, all three patients major Lyme symptoms remained in remission for a period of 25-30 months. In conclusion, Double dose dapsone therapy could represent a novel and effective anti-infective strategy in chronic Lyme disease/PTLDS, especially in those individuals who have failed regular dose dapsone combination therapy (DDS CT) or standard antibiotic protocols. A randomized, blinded, placebo-controlled trial is warranted to evaluate the efficacy of DDD CT in those individuals with chronic Lyme disease/PTLDS.

Green spaces localized in cities create favourable environmental conditions for Ixodes ricinus, the most widespread and important vector of tick-borne pathogens in Central Europe. In this study, we described the prevalence of Borrelia burgdorferi s.l. and Babesia species found in mono- and double infections among I. ricinus ticks occurring in urban areas of the city of Poznań, west-central Poland. Two tick groups were examined: (i) a group of 1,029 host-seeking ticks (460 nymphs, 289 females, and 280 males and (ii) a group of 1,268 engorged female ticks removed from 1,115 tick-infested animals, dogs and cats. The overall prevalence of B. burgdorferi s.l. found in host-seeking ticks was almost two-fold higher in comparison to ticks derived from pets (8.7 vs. 4.7%, respectively, χ2 test, P = 0.001). Borrelia afzelii and B. garinii were the most prevalent species both in ticks from vegetation (3.7% and 3.7%, respectively) and from pets (3.7% and 0.6%, respectively). Babesia infections were slightly more common in feeding ticks compared to those from vegetation (6.0 vs. 4.7%, respectively), however, the difference was not significant. Three Babesia species including Ba. microti, Ba. venatorum and Ba. canis were identified. Babesia canis and Ba. microti were the most prevalent in host-seeking (2.6% and 1.4%, respectively) and feeding ticks (2.8% and 2.2%, respectively), whereas Ba. venatorum was the rarest piroplasm. All Ba microti obtained sequences (n=42) were identical to Ba. microti genotype "Jena/Germany" that is considered as pathogenic to humans. Furthermore, the sequences of Ba. venatorum (n=17) were identical with those isolated from patients in Italy, Austria and Poland. Altogether, out of 121 Babesia-positive ticks, 19.8% were simultaneously infected with B. burgdorferi s.l. spirochetes. We found similar prevalences of co-infections in host-seeking (1.1%) as well as in feeding ticks (1.0%). In the first group, Ba. canis prevailed in coinfections (73%), mostly with B. afzelii and B. garinii, in the second group, Babesia microti dominated with B. afzelii (92.7%). This is the first finding documenting the co-occurrence of both pathogens in ticks from companion animals. The detection of Ba. microti and Ba. venatorum sequences identical to strains pathogenic to humans as well as predominance of LB spirochetes, B. afzelii and B. garinii in I. ricinus from vegetation and animals indicates that there is a potential risk of acquiring human babesiosis and/or Lyme borreliosis in urban areas of the city of Poznań. Although, the overall risk of encountering a Ba. microti and B. burgdorferi s.l. co-infected tick was low (1.0%), the potential for more severe clinical symptoms and complications deserves notice. A relatively high infection rates of Ba. canis in dog-derived ticks (3.2%) and in host-seeking ticks (2.6%), suggests that I. ricinus could potentially be involved in the circulation of this piroplasm in areas, where the competent vector, Dermacentor reticulatus is absent or rare.