Occurrence of Anaplasma spp. in wild lagomorphs from Southern Spain: Molecular detection of new Anaplasma bovis lineages

Wild lagomorphs can act as reservoirs of several pathogens of public and animal health concern. However, the number of studies assessing the presence of Anaplasma spp. in these species is scarce. The aim of the present study was to molecularly identify Anaplasma spp. in wild rabbits (Oryctolagus cuniculus) and Iberian hares (Lepus granatensis) from Southern Spain and assess their epidemiological role in the maintenance of the bacterium. During 2017-2021, spleen samples of 394 wild rabbits and 145 Iberian hares were collected. Anaplasma DNA was detected using different PCR assays (16S rRNA and groEL) and phylogenetic analyses were carried out by Bayesian approach. The possible influence of lagomorph species, age and sex on the prevalence of Anaplasma spp. was evaluated by a multiple logistic regression model. The 9.4% of the rabbits were positive to Anaplasma bovis, but all the hares were negative. No significant differences were found in Anaplasma spp. prevalence regarding to age or sex. This is the first report of A. bovis in lagomorphs from Europe. The phylogenetic analysis of A. bovis confirms the existence of different clusters suggesting the existence of several lineages. In addition, a high divergence of nucleotide identity was observed within the lineage 4, which could result in the under-detection of some strains when using A. bovis-specific PCR, hindering its detection and characterization. Since this analysis is based on a limited number of nucleotide bases and sequences, more studies are needed for further characterize A. bovis, as well as its relationship with other Anaplasma spp.

CLINICAL AND SUBCLINICAL CYTAUXZOON FELIS INFECTIONS IN DOMESTIC CATS FROM A RECENTLY IDENTIFIED ENDEMIC REGION

Cytauxzoon felis is a tick-transmitted intraerythrocytic apicomplexan infecting felids in the southeastern and midwestern United States. Bobcats (Lynx rufus) are the natural wildlife reservoir of C. felis, where in enzootic areas prevalence can reach 100%. Domestic cats can be subclinically infected with C. felis or can develop cytauxzoonosis. Two studies have documented the presence of C. felis in domestic cats in Illinois; these studies have shown a limited number of cases submitted to specialty labs. During 2014-2018, we obtained blood samples collected by veterinary staff from 514 cats that were apparently healthy and 74 cats that were suspected of cytauxzoonosis. These samples were screened using a sensitive, nested PCR to detect the presence of C. felis DNA. We herein document frequent occurrences of cytauxzoonosis (8-15 cases/year from 4 veterinary clinics) and 12.5% prevalence of subclinical infections in southern Illinois, a locality showing a sharp increase in cases of cytauxzoonosis. Our results suggest a high risk of cytauxzoonosis in southern Illinois, despite only recently being recognized in the area. We found no specific risk factors for cytauxzoonosis or subclinical infections in this location. In addition, cases of cytauxzoonosis occur every month of the year (with the highest frequency in summer) and therefore tick prevention should be used in domestic cats in enzootic regions throughout the year.

The long-term efficacy of tick-borne encephalitis vaccines available in Europe - a systematic review

BACKGROUND

Despite the availability of vaccination, TBE (tick-borne encephalitis) remains a global public health problem. Therefore, the aim of our study was to assess the long-term efficacy of vaccinations against tick-borne encephalitis using vaccines available on the European market.

METHODS

The analysis was conducted on the results of a systematic review conducted in accordance with the Cochrane Handbook for Systematic Reviews of Interventions. The search was performed in three databases, namely Medline (via PubMed), EMBASE (via Ovid), and the Cochrane Library database. The authors followed the PRISMA method and the selection of the articles was performed with two independent researchers.

RESULTS

From a total of 199 citations, 9 studies were included in this review. According to the primary studies identified in the search, the efficacy of available anti-TBE vaccines ranges from 90.1% to 98.9%; however, in individuals above the age of 60, the protection wanes as early as one year after vaccination. Administration of a booster dose 3 years after completion of the basic vaccination schedule significantly extended the period of protection against TBE.

CONCLUSIONS

Anti-TBE vaccines available in Europe have a high level of efficacy. However, the level of protection against TBE is decreasing after vaccination. Therefore, in addition to the conventional schedule, booster vaccines should be administered every 5 years in individuals before the age of 60 and more frequently, e.g. every 3 years, in individuals aged 60 and beyond.

Analysis of Rocky Mountain spotted fever cases in Northern Mexico reveals genetic variability of Rickettsia rickettsii and the different distribution of genotypes

Rickettsioses have been reported in parts of Mexico since the last century, with Rocky Mountain spotted fever (RMSF) being one of the most prevalent in northern states. Unfortunately, fatality rates for RMSF in Mexico are higher than in other countries, like the USA. The reason for this difference in fatality rates is currently unknown and could be associated with a genotype of the bacterium, but no comparative molecular typing has been conducted in Mexico to date. The purpose of this study was to analyze 47 RMSF samples with different outcomes from several states in northern Mexico to know the genetic variability of Rickettsia rickettsii, as well as to reconstruct its phylogeny, for which the following intergenic regions were sequenced: RR0155-rpmB, cspA-ksgA, RR1240-tlc5, and Spo0J-abc T1, as well as the following partial genes: ompA, ompB, and gltA. We identified 8 genotypes with different distribution and prevalence among the states analyzed, as well as a different association with case outcome; these genotypes were clustered in 2 clades and 5 lineages were revealed, some of them probably exclusive from Mexico.

A novel variant of Babesia sp. (Piroplasmida) as a hemoparasite in procellariiform seabirds

Procellariiformes includes pelagic seabirds that only use land for breeding; and also, these sites mostly occur in insular habitats. These peculiar habits make the investigation of hemoparasites a challenging issue. Thus, the data on the blood parasites of Procellariiformes are still scarce. In the order Piroplasmida, 16 species of Babesia have been described in terrestrial birds and seabirds. However, there is no register for Babesia spp. in procellariiform seabirds. Hence, the objective of this survey was to investigate the occurrence of Babesia spp. in these seabirds. A total of 220 tissue samples from 18 different seabird species were analyzed; the samples comprised blood and fragments of liver and spleen. The samples were obtained from live rescued animals and carcasses found along the southern coast of Brazil. Polymerase chain reaction (PCR) was conducted, followed by phylogenetic analysis. Only one blood sample yielded a positive result, from an adult female Thalassarche chlororhynchos (Atlantic yellow-nosed albatross). The sequence obtained showed the highest identity with sequences of Babesia spp. of birds from the South Pacific, and the isolate was named Babesia sp. strain Albatross. In the phylogenetic analysis, the sequence was grouped within the Babesia sensu stricto group, and further still into a subgroup including Babesia spp. of the Kiwiensis clade (parasites from birds). The phylogenetic analysis also showed that Babesia sp. strain Albatross clustered apart from the Peircei group, a clade that includes Babesia spp. from seabirds. As far as it is known, this is the first report of Babesia sp. in procellariiform seabirds. Babesia sp. strain Albatross may constitute a novel variant of tick-borne piroplasmids associated with the Procellariiformes order.

Infection related membranoproliferative glomerulonephritis secondary to anaplasmosis: A case report

BACKGROUND

Anaplasmosis is a tick-borne disease with a range of clinical manifestations, from a flu-like illness with fever and myalgias to a severe systemic disease with multisystem organ failure. Although renal involvement is not a common presentation, there have been few cases reporting acute kidney injury from Anaplasmosis.

CASE SUMMARY

We present a 55-year-old female with anaplasmosis who developed acute kidney injury due to membranoproliferative glomerulonephritis (MPGN). The patient originally presented with cough and shortness of breath. She was admitted to the hospital with a diagnosis of community acquired pneumonia and received antibiotics. During the hospital course she developed severe acute renal failure. Initial serological work up didn’t provide any conclusive diagnosis. Hence, she underwent kidney biopsy which showed MPGN pattern suggesting autoimmune, multiple myeloma or infectious etiology. Extensive work up was undertaken which was negative for autoimmune diseases, vasculitis panel, paraproteinemias but tested positive for IgG anaplasma with high titers indicating Anaplasmosis.

CONCLUSION

Our case shows a unique presentation of severe acute renal failure from MPGN from tick borne illness. MPGN is usually seen with autoimmune diseases, hepatitis C virus infections, paraproteinemias. Hence, we suggest that tick borne illness should also be considered when evaluating acute renal failure cases in tick borne prevalent regions.

Molecular prevalence of tick-borne haemoprotozoan diseases in cattle of North Eastern state of Tripura, India

The tick-borne haemoprotozoan diseases are major constraint in the health and production of cattle and causes substantial losses to the livestock industry throughout the world. Tripura is a northeastern state of India characterized by a warm humid tropical climate and high rainfall which is conducive to the multiplication of vector-ticks of haemoprotozoan diseases. A total of 320 tick-infested cattle (22 male and 298 female) of either sex was selected randomly from different district of Tripura for the detection of carrier cattle infected with tick-borne haemoparasites from July, 2017 to June, 2019. Out of 320 tick-infected cattle, 4.69% prevalence of B. bigemina infection in cattle was found while Theleria spp. was not prevalent in the collected blood sample by using polymerase chain reaction. The prevalence of B. bigemina was significantly (< 0.05) higher in cattle more than 3 years of age (6.72%) compared to the 1-3 years age group (3.97%) and < 1 year age groups (1.66%). Sex-wise B. bigemina infection was significantly (< 0.05) seen only in female (5.03%) cattle infested with ticks. The district-wise B. bigemina prevalence (%) in Tripura was as in cattle; Dhalai (0.63), Sipahijala (0.31), Khowai (0.31), Gomati (0.31), South Tripura (0.63), North Tripura (0.31), Unakoti (0.31) and West Tripura (1.87) respectively. The use of PCR assays for the detection of B. bigemina and Theileria spp. in the North Eastern state of Tripura of India showed prevalence of 4.69% and 0%, respectively in tick-infested cattle. This study is the first report about the prevalence of tick-borne haemoprotozoan diseases from cattle of Tripura and suggest that babesiosis is more common disease as compared to theileriosis and is more prevalent in adult female tick-infested cattle in Tripura.

Using next generation sequencing for molecular detection and differentiation of Anaplasma phagocytophilum variants from host seeking Ixodes scapularis ticks in the United States

Anaplasmosis is increasingly common in the United States, with cases being reported over an expanding geographic area. To monitor for changes in risk of human infection, the U.S. Centers for Disease Control and Prevention monitors the distribution and abundance of host-seeking vector ticks (Ixodes scapularis and Ixodes pacificus) and their infection with Anaplasma phagocytophilum. While several variants of A. phagocytophilum circulate in I. scapularis, only the human-active variant (Ap-ha) appears to be pathogenic in humans. Failure to differentiate between human and non-human variants may artificially inflate estimates of the risk of human infection. Efforts to differentiate the Ap-ha variant from the deer variant (Ap-V1) in ticks typically rely on traditional PCR assays coupled with sequencing of PCR products. However, laboratories are increasingly turning to Next Generation Sequencing (NGS) to increase testing efficiency, retain high sensitivity, and increase specificity compared with traditional PCR assays. We describe a new NGS assay with novel targets that accurately segregate the Ap-ha variant from other non-human variants and further identify unique clades within the human and non-human variants. Recognizing that not all investigators have access to NGS technology, we also developed a PCR assay based on one of the novel targets so that variants can be visualized using agarose gel electrophoresis without the need for subsequent sequencing. Such an assay may be used to improve estimates of human risk of developing anaplasmosis in North America.

Human Granulocytic Anaplasmosis

Human granulocytic anaplasmosis (HGA) is a bacterial infection caused by Anaplasma phagocytophilum and transmitted by the bite of the black-legged (deer tick) in North America. Its incidence is increasing. HGA can be transmitted after 24 to 48 hours of tick attachment. The incubation period is 5 to 14 days after a tick bite. Symptoms include fever, chills, headache, and myalgia. Complications include shock, organ dysfunction, and death. Mortality is less than 1% with appropriate treatment. Doxycycline is first line treatment for all ages. Start it empirically if symptoms and risk factors suggest HGA. PCR is the confirmatory test of choice.

Francisella tularensis caused cervical lymphadenopathy in little children after a tick bite: Two case reports and a short literature review

Although Francisella (F.) tularensis is a well-described and understood zoonotic pathogen, its importance in Central Europe is relatively minor and, as such, tularaemia may be missed in the differential diagnosis. The annual incidence of tularaemia in the Czech Republic is relatively stable with up to 100 reported cases per year, except in the epidemic years 1998 and 1999 with 225 and 222 reported cases, respectively. It is, however, higher in comparison with the neighbouring countries. The common route of transmission in Central Europe is handling infected animals. Tularaemia is not commonly recognized as a tick-borne disease. Here we report two rare cases of a tick bite-associated ulceroglandular form of tularaemia in 2.5-year-old and 6.5-year-old children presenting with cervical lymphadenopathy. The unusual and interesting features of those cases are the young age and relatively uncommon route of transmission suggesting possible changes in the epidemiology of tularaemia in the Czech Republic. Therefore, the infection with F. tularensis should be considered in the differential diagnosis after a tick bite even in infants.

Serological and Molecular Detection of Anaplasma spp. in Blood From Healthy Horses: A Preliminary Study of Horses in East Texas

Anaplasmosis is a disease caused by the bacterium Anaplasma phagocytophilum, which is spread by infected ticks. In horses, A. phagocytophilum generally causes transient infection characterized by fever, lethargy, inappetence, ventral edema, petechiae, icterus, ataxia, recumbency, muscle stiffness, and, in severe cases, death. Following natural infection, horses retain antibodies for approximately 2 years, which can be detected through an immunofluorescence antibody assay. Current infections are determined through PCR assay of white blood cell DNA. For this study, whole blood was collected from apparently healthy horses located in East Texas (n = 70), west Texas (n = 3), New York (n = 49), and New Jersey (n = 11) for the determination of serum antibodies and PCR testing of bacterial DNA. Of the 133 horses, 24 tested positive for DNA presence of A. phagocytophilum, and 107 tested positive for serum antibodies. Of the 24 horses testing positive for A. phagocytophilum, 16 were positive for serum antibody presence and 8 were negative. Twenty of the msp2 positive horses were located in East Texas and 4 resided in New York. For serum antibodies, 100% of New York and New Jersey horses tested positive, while only 66% of Texas horses tested positive. This study provides evidence that a large number of horses are exposed to A. phagocytophilum and that this bacterium is present in East Texas. No Texas horse owners reported treatment for anaplasmosis, and the currently infected horses were not demonstrating signs of illness at the time of sample collection. Further research to understand the differences in disease severity amongst equine populations is warranted.

Colorado tick fever virus induces apoptosis in human endothelial cells to facilitate viral replication

Colorado tick fever virus (CTFV) belongs to the genus Coltivirus of the Reoviridae family, and it is the causative agent of Colorado tick fever. Symptoms of the infection are characterized by sudden biphasic fever, headache, and petechial rash, while severe forms of the disease can include meningoencephalitis, hemorrhagic fever, and death in children. However, the mechanisms underlying CTFV induced pathology and severe complications remain unknown. As CTFV is spread by tick bites and disseminates systemically via hematogenous routes, we performed in vitro analysis examining the interactions between endothelial cells (ECs) and CTFV. Our findings indicate that dermal microvascular ECs, HMEC-1, are susceptible and permissive to CTFV infection. To investigate the role of CTFV infection on endothelial barrier function, we assessed transendothelial electrical resistance (TEER) by xCELLigence and observed a dose-dependent decrease in cell index, indicating increased vascular permeability starting at approximately hour 18 (MOI=1) and hour 26 (MOI=0.1). Since CTFV induced cytopathic effect and increased vascular permeability in HMEC-1 cells, we hypothesized that CTFV causes apoptotic cell death. Our results showed that HMEC-1 cells infected with CTFV at 48 h caused a significant increase in Annexin V staining with reduced viability compared to uninfected cells suggesting CTFV induces apoptotic cell death in human ECs. Electron microscopy also was consistent with apoptotic features, including chromatin condensation and cell blebbing. Furthermore, CTFV induced caspase-3/7 activation at 24 and 48 h post-infection (hpi). The inhibition of caspase activity using Z-VAD-FMK reduced CTFV induced cell death and significantly reduced viral titer. These results indicated that CTFV can infect ECs, exerting direct adverse effects, leading to vascular permeability and cell death. Overall, our data suggest that caspase-mediated apoptosis is a critical mechanism by which CTFV induces disease in the host and enhances viral replication. Future studies will examine the viral and cellular determinants involved in CTFV induced apoptosis in human ECs.

Mapping the distribution and risk factors of Anaplasmataceae in wild and domestic canines in Chile and their association with Rhipicephalus sanguineus species complex lineages

Anaplasma platys and Ehrlichia canis are members of the Anaplasmataceae family that cause disease in dogs and are mainly transmitted by Rhipicephalus sanguineus species group ticks. We performed a cross-sectional study on these pathogens across six bioclimatic regions of Chile, including 719 free-ranging rural dogs, 132 Andean foxes (Lycalopex culpaeus), and 82 South American gray foxes (Lycalopex griseus). Dog and fox blood samples were first screened for DNA of Anaplasmataceae followed by two Ehrlichia-specific protocols. Antibodies against Anaplasma sp. and E. canis were assessed by immunofluorescence in dogs. Ectoparasites were collected and identified, with the determination of the lineages of the Rhipicephalus sanguineus species group by molecular and phylogenetic analyses. Finally, potential risk factors for infection were investigated across the different bioclimatic regions and host species. All DNA amplicons obtained from the screening protocol corresponded to Anaplasma platys. The occurrence of both A. platys DNA and antibodies was confirmed in all six bioclimatic regions, except for regions at high altitude and/or without either R. sanguineus species group lineage present. Dogs infested with R. sanguineus ticks were significantly more prone to be infected and exposed to Anaplasma spp. Prevalence of DNA was significantly higher in juvenile (19%) than in adult dogs (9%), whereas the opposite was found for seroprevalence (19% versus 35%, respectively). Overall prevalence of A. platys DNA was higher in dogs (11%) than in foxes (4%), probably owing to markedly lower tick infestations in the foxes. Ehrlichia canis DNA was not detected in any sample, and antibodies against this pathogen were detected only in four dogs, in areas with both R. sanguineus lineages present. Free-ranging dogs in Chile could be favoring the maintenance of A. platys in all areas suitable for its tick vector. Although apparently infrequent, spillovers from dogs to foxes may be taking place and should be considered in management plans in Chile.

Parasites of wombats (family Vombatidae), with a focus on ticks and tick-borne pathogens

Ticks (Arachnida: Acari) are vectors for pathogens and the biggest threat to animal health. Many Australian ticks are associated with pathogens that impact humans, domestic animals and livestock. However, little is known about the presence or impact of tick-borne pathogens in native Australian wildlife. Wombats are particularly susceptible to the effects of the ectoparasite Sarcoptes scabiei which causes sarcoptic mange, the reason for which is unknown. Factors such as other ectoparasites and their associated pathogens may play a role. A critical understanding of the species of ectoparasites that parasitise wombats and their pathogens, and particularly ticks, is therefore warranted. This review describes the ectoparasites of wombats, pathogens known to be associated with those ectoparasites, and related literature gaps. Pathogens have been isolated in most tick species that typically feed on wombats; however, there are minimal molecular studies to determine the presence of pathogens in any other wombat ectoparasites. The development of next-generation sequencing (NGS) technologies allows us to explore entire microbial communities in ectoparasite samples, allowing fast and accurate identification of potential pathogens in many samples at once. These new techniques have highlighted the diversity and uniqueness of native ticks and their microbiomes, including pathogens of potential medical and veterinary importance. An increased understanding of all ectoparasites that parasitise wombats, and their associated pathogens, requires further investigation.

Identification of Anaplasma marginale in long-eared hedgehogs (Hemiechinus auritus) and their Rhipicephalus turanicus ticks in Iran

Hedgehogs play a role in the eco-epidemiology of parasites, viruses and bacteria of veterinary and medical importance. In Europe, hedgehogs have been found infected with tick-transmitted Anaplasma phagocytophilum and A. marginale. In this study blood and ticks collected from 53 long-eared hedgehogs (Hemiechinus auritus) living in southeastern Iran close to Afghanistan and Pakistan borders were examined for Anaplasma spp. infection using microscopical and molecular biology methods. At microscopical examination Anaplasma-like inclusion bodies were found at the margin of erythrocytes in the blood smear of one infected hedgehog (prevalence 1.9 %). Each hedgehog was infested with three to eight adult ticks (average 4.7 ± 1.5). On the body of hedgehogs, the ears were the main site for attachment of ticks. Out of 248 collected adult ticks 81.4 % were Rhipicephalus sanguineus sensu lato and 18.5 % were R. turanicus. PCR and sequencing showed the presence of A. marginale infection in the blood of two hedgehogs (3.8 %) and R. turanicus ticks collected from them. This is the first report of A. marginale infection in hedgehogs in Iran. Epidemiological importance of this finding is discussed and current knowledge on the tick fauna of hedgehogs in the country is reviewed.

Borrelia in neotropical bats: Detection of two new phylogenetic lineages

The genus Borrelia encompasses 50 spirochetal species, several of which are pathogenic and have been detected in a wide range of mammals, especially rodents and cervids. Although the order Chiroptera is the second most diverse mammalian order, and borreliosis represents a human and veterinary health problem in endemic countries, few studies have previously reported infections of Borrelia in these flying mammals. For this reason, the aim of the present study was to detect the presence of, and to analyze the diversity of Borrelia species in several bat species from Mexico. A total of 69 bats belonging to 11 species were collected and molecular detection of Borrelia was performed by amplifying three genes using specific primers. Only five individuals of four bat species (Saccopteryxbilineata, Choeroniscus godmani, Sturnira parvidens and Lasiurus cinereus) tested positive for Borrelia DNA. We now show the first Borrelia record in Mexican bats from two different ecosystems, where previously several potential vector species of the genus Ixodes and Ornithodoros had been reported. The Borrelia sequences obtained from the bats revealed two new putative lineages, one from the relapsing fever group and the second one belonging to the Borrelia burgdorferi s.l. complex, both of which are related to zoonotic species. These results highlight the importance of bats as potential hosts of Borrelia, and the imperative need of active surveillance in flying mammals in order to understand their potential role in the life cycle of this bacteria genus.

Assessing human exposure to spotted fever and typhus group rickettsiae in Ontario, Canada (2013-2018): a retrospective, cross-sectional study

BACKGROUND

Assessing the burden of rickettsial infections in Ontario, Canada, is challenging since rickettsial infections are not reportable to public health. In the absence of reportable disease data, we assessed the burden of rickettsial infections by examining patient serological data and clinical information.

METHODS

Our retrospective, cross-sectional study included patients who had Rickettsia serological testing ordered by their physician, in Ontario, from 2013 to 2018. We tested sera from 2755 non-travel patients for antibodies against spotted fever group rickettsiae (SFGR) and typhus group rickettsiae (TGR) using an indirect immunofluorescence assay (IFA) (positive IgG titers ≥1:64). We classified cases using a sensitive surveillance case definition: confirmed (4-fold increase in IgG titers between acute and convalescent sera with clinical evidence of infection), possible (single positive sera with clinical evidence) and previous rickettsial infection (single positive sera without clinical evidence). We classified cases seropositive for both SFGR and TGR as unspecified Rickettsia infections (URIs).

RESULTS

Less than 5% of all patients had paired acute and convalescent sera tested, and of these, we found a single, laboratory-confirmed SFGR case, with a 4-fold increase in IgG titers and evidence of fever, maculopapular rash and headache. There were 45 possible (19 SFGR, 7 TGR, 19 URI) and 580 previous rickettsial infection (183 SFGR, 89 TGR, 308 URI) cases. The rate of positive tests for SFGR, TGR and URI combined (all case classifications) were 4.4 per 100,000 population. For confirmed and possible cases, the most common signs and symptoms were fever, headache, gastrointestinal complaints and maculopapular rash. The odds of having seropositive patients increased annually by 30% (odds ratio = 1.3, 95% confidence interval: 1.23-1.39).

CONCLUSIONS

The rates of rickettsial infections in Ontario are difficult to determine. Based on confirmed and possible cases, rates are low, but inclusion of previous rickettsial infection cases would indicate higher rates. We highlight the need for education regarding the importance of testing acute and convalescent sera and consistent completion of the laboratory requisition in confirming rickettsial disease. We suggest further research in Ontario to investigate rickettsial agents in potential vectors and clinical studies employing PCR testing of clinical samples.

Kyasanur Forest disease virus non-mouse animal models: a pilot study

Objectives

Mouse models have delivered variable recapitulation of Kyasanur Forest disease (KFD) pathology and consistently demonstrated neurological involvement which may be a limited feature of human disease. With the purpose of more accurately modelling human disease progression we infected several small-mammalian models: guinea pigs, hamsters and ferrets with a titered infectious dose of Kyasanur Forest disease virus (KFDV). Clinical indicators of disease severity were observed for seventeen days, on day eighteen a visual post-mortem analysis of visceral organs was conducted. Viral load in selected tissues was measured to infer disease signs and the establishment of viral replication.

Data description

Daily monitoring did not reveal any observable signs of illness; weight loss was minimal across species and gross pathology did not indicate severe viral infection. Tissue specific tropism and establishment of viral infection was monitored by quantitative real-time polymerase chain reaction (qRT-PCR). No viral replication was detected in ferrets (n = 0/3), but was present in the spleen of guinea pigs (n = 3/3) and the brain of hamsters (n = 3/3). Low levels of viral RNA were detected in multiple hamster tissues (kidney, liver, lung and spleen) suggesting the possibility of viral tropism and possible adaptation to the host. No serological tests were performed.

Anaplasmataceae closely related to Ehrlichia chaffeensis and Neorickettsia helminthoeca from birds in Central Europe, Hungary

Increasing amount of data attest that (in the context of vector-borne infections) birds are not only important as hosts of blood-sucking arthropod vectors, but also as reservoirs of vector-borne pathogens. From 2015 to 2019 cadavers of 100 birds (from 45 species, nine orders) were collected in Hungary, and their organs were screened for DNA from a broad range of vector-borne bacteria with PCR and sequencing. Molecular analyses revealed the presence of Anaplasmataceae, and sequencing identified bacteria closely related to Neorickettsia helminthoeca and Ehrlichia chaffeensis in a Eurasian teal (Anas crecca) and a song thrush (Turdus philomelos), respectively. All samples were PCR negative for rickettsiae, borreliae, Francisella and Coxiella spp., as well as for piroplasms. To our knowledge, this is the first report of a Neorickettsia and an Ehrlichia sp., which belong to the phylogenetic groups of N. helminthoeca and E. chaffeensis, respectively, from Europe. The potential presence of these two vector-borne bacteria needs to be taken into account during future studies on the eco-epidemiology of Anaplasmataceae in Europe.

Bovine anaplasmosis herd prevalence and management practices as risk-factors associated with herd disease status

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Bovine anaplasmosis has a wide distribution across the State of Kansas.

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Several commonly promoted management practices associated with anaplasmosis were found to be associated with herd infection status.

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Many commonly promoted management practices were found to not be associated with herd infection status.

Bovine anaplasmosis is a hemolytic disease of cattle caused by Anaplasma marginale which can cause anemia, adult mortality, abortion, and performance reduction. The objectives of this study were to estimate herd-level infection prevalence of bovine anaplasmosis in Kansas cow-calf herds and assess management practices associated with herd infection status. Licensed Kansas veterinarians were randomly selected and provided clientele to generate randomly selected participant herds. Blood samples were collected from 10 mature cows during processing of 925 herds between October 1, 2016 and March 1, 2017. A management survey was completed by 780 herd-owners. Sample status was determined by competitive enzyme-linked immunosorbent assay (cELISA); operations indicating vaccination for anaplasmosis were tested with A.marginale-specific polymerase chain reaction (PCR). Survey data underwent logistic regression analysis for calculation of odds ratios and confidence intervals. The herd-level prevalence was 52.5 % of cow-calf herds. Prevalence ranged from 19.1 % of herds in Western Kansas to 87.3 % of herds in Eastern Kansas. Vaccinated herds were more likely (OR = 2.38; CI = 1.16–4.85; p =  0.02) to be positive compared to non-vaccinated herds, and herds that utilized insecticide ear-tags were more likely to be positive (OR = 1.9; CI = 1.42–2.55; p < 0.01) compared to herds which do not. Operations that prescribe-burned 21–50 % and >50 % of their pastures were more likely to be test positive, OR = 5.74 (CI = 3 .14–10.51; p < 0.01) and OR = 4.78 (CI = 2.33–10.17; p < 0.01), respectively, than operations that prescribe-burned <20 % of their pastures. In summary, anaplasmosis is present across Kansas beef herds at varied prevalence levels and selected management practices were found to be associated with herd infection status.

Lyme disease in children: Data from the Canadian Paediatric Surveillance Program

BACKGROUND

Lyme disease (LD) is an infectious disease that is emerging in eastern and central Canada associated with the spread of the tick vector Ixodes scapularis. National surveillance shows that children are an at-risk age group.

OBJECTIVES

To study the epidemiology of LD in Canadian children using the Canadian Paediatric Surveillance Program (CPSP) to better understand exposure history, clinical manifestations, diagnosis and treatment of paediatric LD cases in Canada.

METHODS

A structured questionnaire was completed by paediatricians for each LD case reported as part of the Canadian Paediatric Surveillance Program from 2014 to 2017.

RESULTS

There were 95 cases that met inclusion criteria as confirmed or probable cases. The median age was 7 years; 38 % were 5-9 years and 35 % were 10-15 years of age. Most cases were acquired in known Canadian endemic locations; 5 were acquired during travel to the US. Most cases were reported from Nova Scotia and Ontario (46 % and 38 % respectively). The most common clinical presentation was arthritis (59 % of all cases), which is a manifestation of the late disseminated stage of LD. Late disseminated disease presented through the year, whereas early LD (Erythema migrans) and early disseminated LD presented during the summer and fall. Antibiotic choice and duration of therapy generally followed accepted guidelines.

CONCLUSION

This study of the clinical spectrum of LD in Canadian children underlines the need for preventive measures to protect children in Canada from emerging LD, and the need for health care provider awareness.

A framework for adaptive surveillance of emerging tick-borne zoonoses

Significant global ecological changes continue to drive emergence of tick-borne zoonoses around the world. This poses an important threat to both human and animal health, and highlights the need for surveillance systems that are capable of monitoring these complex diseases effectively across different stages of the emergence process. Our objective was to develop an evidence-based framework for surveillance of emerging tick-borne zoonoses. We conducted a realist review to understand the available approaches and major challenges associated with surveillance of emerging tick-borne zoonoses. Lyme disease, with a specific focus on emergence in Canada, was used as a case study to provide real-world context, since the process of disease emergence is ongoing in this country. We synthesize the results to propose a novel framework for adaptive surveillance of emerging tick-borne zoonoses. Goals for each phase of disease emergence are highlighted and approaches are suggested. The framework emphasizes the needs for surveillance systems to be inclusive, standardized, comprehensive and sustainable. We build upon a growing body of infectious disease literature that is advocating for reform to surveillance systems. Although our framework has been developed for tick-borne zoonoses, it is flexible and has the potential to be applied to a variety of other vector-borne and zoonotic diseases.

Vector-borne bacteria in blood of camels in Iran: New data and literature review

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Information about vector-borne bacteria of camels is scarce.

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Anaplasmataceae, SFG rickettsiae, Bartonella and Borrelia were investigated in blood of 200 dromedary camels of Iran.

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PCR results revealed 30 animals (15%) to be infected with Anaplasmataceae bacteria.

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BlastN® analysis of positive samples revealed identity with “Candidatus Anaplasma camelii” isolates.

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This paper reviews the current knowledge on camels’ tick-borne bacteria including microscopy, serology and molecular studies.

Despite close association between camels and humans, molecular based studies on vector-borne pathogens infecting camels are scarce compared to other animals in Iran. The current study was carried out to investigate the occurrence of vector-borne bacteria in the blood of dromedaries by molecular tools. A total of 200 peripheral blood samples were collected from apparently healthy animals. Microscopic examination was performed on Giemsa-stained blood smears, and drops of blood were spotted on Whatman FTA^® cards for molecular analyses. Genomic DNA was extracted from the cards, and PCR amplification followed by sequencing of positive samples was carried out for the detection of Anaplasmataceae, spotted fever group (SFG) rickettsiae, Bartonella spp. and Borrelia spp. Intra-cytic forms of any blood pathogens could not be detected by light microscopy. PCR results revealed 30 animals (15%) to be infected with Anaplasmataceae bacteria. Analyses of sequences revealed a strain of Anaplasma sp. identical to Candidatus Anaplasma camelii isolated from camels, cattle and deer in Asia and Africa. Neither SFG rickettsiae, nor Borrelia or Bartonella species were found. Further studies for determining epidemiological role of camels and its zoonotic potential are recommended. This paper reviews the current knowledge on camels’ tickborne bacteria including microscopy, serology and molecular studies.

The impact of vector control on the prevalence of Theileria cervi in farmed Florida white-tailed deer, Odocoileus virginianus

Background

Vector-borne diseases exert a global economic impact to the livestock industry. Understanding how agriculture practices and acaricide usage affect the ecology of these diseases is important for making informed management decisions. Theileria cervi is a hemoprotozoan parasite infecting white-tailed deer (Odocoileus virginianus) and is transmitted by the lone star tick, Amblyomma americanum. The purpose of this study was to determine if acaricide treatment decreased hematozoan prevalence in farmed white-tailed deer when compared to geographically-close wild deer or altered the genotypes of T. cervi present.

Results

We compared prevalence of T. cervi in 52 farmed adult white-tailed deer which were regularly treated with permethrin and ivermectin, 53 farmed neonates that did not receive treatment for vector control, and 42 wild deer that received no form of chemical vector control. Wild deer had significantly higher prevalence of T. cervi than farmed deer. Additionally, no neonate fawns tested positive for T. cervi, and we found that age was a significant predictor of infection status. We found no difference in genotypic variation in T. cervi isolates between adjacent herds of farmed and wild white-tailed deer, although a divergent genotype X was identified. Chronic infection with T. cervi had no significant effects on mortality in the white-tailed deer.

Conclusions

We found significantly lower prevalence of T. cervi infection in farmed (40%) compared to wild white-tailed deer (98%), which may be due to the inclusion of chemical vector control strategies. More work is needed to determine the implications, if any, of mixed genotypic infections of T. cervi, although we found no significant effect of infection with Theileria on mortality in farmed deer. Theileria infection does sometimes cause disease when an animal is stressed, immunosuppressed, or translocated from non-endemic to endemic regions.

Molecular Detection of Anaplasma Phagocytophilum as a Zoonotic Agent in Owned and Stray Dogs in Tehran, Iran

The genus Anaplasma is an obligated intracellular Rickettsia and among its species, Anaplasma phagocytophilum (A. phagocytophilum) is a zoonotic agent that infects host neutrophils. The aim of this study was molecular detection of A. phagocytophilum infection based on MSP4 gene in owned and stray dogs in Tehran, capital of Iran. One hundred and fifty blood samples were collected from dogs in Tehran and suburbs of Tehran, Iran. Firstly, the thin blood smears were prepared and Giemsa staining method was conducted. Then, the samples were examined under oil immersion objective and 0.67% of them were observed infected with A. phagocytophilum. The DNA was extracted from blood samples using a DNA isolation kit (MBST, Iran), and MSP4 gene extraction was performed by Polymerase chain reaction (PCR) and nested-PCR. Finally, 2% of the samples were positive for A. phagocytophilum. The data were analyzed using SPSS software (version 19.0) and Chi-square test was performed. There was no significant relation between infection and age, as well as sex and ectoparasitic infestation (P&amp;gt;0.05). This article was a report of A. phagocytophilum infection in dogs and their potentials as host carriers of this important microorganism in Tehran, Iran.

Prevalence of Borrelia burgdorferi, Anaplasma spp., Ehrlichia spp. and Dirofilaria immitis in Canadian dogs, 2008 to 2015: a repeat cross-sectional study

Background

Vector-borne pathogens are emerging concerns in multiple regions of Canada. Determining regional prevalence of canine vector-borne pathogens and documenting change will improve clinician awareness, enable targeted prevention, enhance diagnosis and ideally reduce the risk of disease. Study objectives were to: (i) estimate the prevalence of positive canine vector-borne test results from samples submitted in Canada; (ii) assess change in prevalence over time, from baseline (2008) to 2015; and (iii) estimate the prevalence of pathogen co-infections.

Methods

This repeat cross-sectional study evaluated 753,468 test results for D. immitis antigen and B. burgdorferi, Ehrlichia canis/ewingii/muris serology, and 753,208 test results for Anaplasma phagocytophilum/platys serology using the SNAP® 4Dx®Test and SNAP 4Dx® Plus Test.

Results

Based on all submitted samples from Canada (2008–2015), the period seroprevalence of B. burgdorferi, Ehrlichia spp., Anaplasma spp. and D. immitis antigen were 2.0%, 0.5%, 0.4% and 0.2%, respectively. Over the 7 years (2008 compared to 2015) we observed a significant increase in seroprevalence for B. burgdorferi (144.4%) and Ehrlichia spp. (150%). Co-infections (positive for two or more pathogens on a single 4 pathogen test kit) were estimated at 5.4% (1162/21,612) of total positive tests.

Conclusions

The temporal rise and geographical differences in prevalence detected for these pathogens (notably B. burgdorferi) are consistent with anecdotal information on canine illness related to tick-borne pathogen exposure in multiple regions of Canada, particularly canine Lyme disease.

Electronic supplementary material

The online version of this article (10.1186/s13071-019-3299-9) contains supplementary material, which is available to authorized users.

Assessing the natural circulation of canine vector-borne pathogens in foxes, ticks and fleas in protected areas of Argentine Patagonia with negligible dog participation

We collected blood and/or ectoparasites from 49 South American grey foxes (Lycalopex griseus) and two Andean foxes (L. culpaeus) caught in two National Parks of southern Argentine Patagonia (Bosques Petrificados, BPNP; and Monte León, MLNP) where dogs are nearly absent (density < 0.01 dog/km²). Common ectoparasites were the flea Pulex irritans (88% prevalence) and the tick Amblyomma tigrinum (29%). Conventional PCR and sequencing of 49 blood samples, 299 fleas analysed in 78 pools, and 21 ticks revealed the presence of DNA of the following canine vector-borne pathogens: in grey foxes, Rickettsia sp. (3%), hemoplasmas (8%), including Mycoplasma haemocanis, and Hepatozoon sp. (50%); in P. irritans, Bartonella spp. (72% of flea pools from 76% of foxes), mostly B. vinsonii subsp. berkhoffii but also B. rochalimae, Anaplasmataceae (Wolbachia sp.; 60% and 54%), and M. haemocanis/haemofelis (29% and 18%); and in A. tigrinum, Hepatozoon sp. (33% of ticks in 4 of 7 foxes). No piroplasmid DNA was detected in any sample. Andean foxes were negative for all tested pathogens. Two different Hepatozoon haplotypes were detected: the most prevalent was phylogenetically associated with H. felis, and the other with H. americanum and related sequences. Amblyomma tigrinum and Hepatozoon sp. were more abundant and/or prevalent in BPNP than in colder MLNP, 300 km southwards, perhaps located close to the limit for tick suitability. Bartonella v. berkhoffii was also significantly more prevalent in fleas of foxes in BPNP than in MLNP. This study provides novel information about natural host-pathogen associations in wildlife, markedly extends the distribution area in South America of arthropods and vector-borne pathogens of veterinary and public health interest, and contributes preliminary evidence about the potential role of A. tigrinum and P. irritans as vectors, respectively, for potentially new species of Hepatozoon from Lycalopex spp. and for M. haemocanis that should be further investigated.

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Foxes and their ticks and fleas analysed in two remote areas of Argentine Patagonia.

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Hepatozoon (50%), hemoplasmas (8%), Rickettsia (3%) DNA detected in foxes.

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Two Hepatozoon haplotypes: one related with H. felis, the other with H. americanum.

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Role of Amblyomma tigrinum as Hepatozoon vector is proposed.

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Bartonella and hemoplasma DNA detected in P. irritans from 76% and 18% of foxes.

A new TaqMan method for the reliable diagnosis of Ehrlichia spp. in canine whole blood

Background

Ehrlichiosis is an important emerging infectious disease of the canid family and humans worldwide. To date, no extensive evaluation or validation of a molecular diagnostic test for ehrlichiosis has been published. Here, we present data for a newly designed TaqMan assay and compare its performance to a commercial technology (PCRun®). Both of these real-time methods of analysis were evaluated using a comprehensive number of prospective and retrospective samples collected from dogs exhibiting symptoms of ehrlichiosis.

Results

Whole blood samples collected from dogs, retrospectively in the United Kingdom and prospectively in Israel, were analysed for the presence of Ehrlichia canis and Ehrlichia minasensis DNA using the TaqMan PCR, developed specifically for this study. The results were compared to those of a real time commercial isothermal amplification method (PCRun® system developed by Biogal Galed Labs ACS, Galed, Israel). The sensitivity and specificity (CI: 95%) of the TaqMan PCR and PCRun® were both determined to be 100% and absolute, for all of the samples tested. Interestingly, both tests were demonstrated to be highly comparable, irrespective of differences in amplification chemistry or sequences targeted. Host differences, incidence of disease and geographical location of the isolates had little impact on the positivity recorded by each of the diagnostic methods.

Conclusions

It was evident that both amplification methods were equally suited for diagnosing canine ehrlichiosis and while the PCRun® clearly amplified all clinically relevant Ehrlichia species known to infect dogs and humans, the TaqMan method was more specific for E. canis and E. minasensis. This work demonstrates that despite good analytical sensitivities and specificities for Ehrlichia spp. neither method could fully account for the clinical diagnosis of thrombocytopenia.

Electronic supplementary material

The online version of this article (10.1186/s13071-018-2914-5) contains supplementary material, which is available to authorized users.

Multiple organ involvement in severe fever with thrombocytopenia syndrome: an immunohistochemical finding in a fatal case

Background

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease caused by SFTS bunyavirus (SFTSV), a tick borne bunyavirus. However, Immunohistochemistry of SFTS patients are not well studied.

Methods

We obtained multiple of tissues from a fatal case with SFTS, including blood, lungs, kidneys, heart, and spleen. The blood samples were used to isolate the causative agent for detection of viral RNA and further expression of recombinant viral protein as primary antibody. Immunohistochemistry of the heart, lungs, spleen and kidneys was used to characterize the viral antigen in tissue sections.

Results

A 79-year-old man, together with his wife, was admitted because of fever. Both patients were diagnosed with SFTS by the positive SFTSV RNA in the blood. The gentleman died of multiple organ failure 8 days after hospitalization. However, his wife recovered and was discharged. Immunohistochemistry indicated that SFTSV antigens were present in all studied organs including the heart, kidney, lung and spleen, of which the spleen presented with the highest amount of SFTSV antigens. The kidney was next while the heart and lungs showed lower amount of SFTSV antigens.

Conclusions

SFTSV can direct infect multiple organs, resulting in multiple organ failure and ultimately in an unfavorable outcome.

Electronic supplementary material

The online version of this article (10.1186/s12985-018-1006-7) contains supplementary material, which is available to authorized users.

Development of a tick-borne pathogen QPCR panel for detection of Anaplasma, Ehrlichia, Rickettsia, and Lyme disease Borrelia in animals

Anaplasma spp., Ehrlichia spp., Rickettsia spp., and Lyme disease associated Borrelia spp. are the most common tick-borne pathogens reported to infect human beings worldwide and other animals, such as dogs and horses. In the present study, we developed a broad-coverage SYBR Green QPCR panel consisting of four individual assays for the detection and partial differentiation of the aforementioned pathogens. All assays were optimized to the same thermocycling condition and had a detection limit of 10 copies per reaction. The assays remained sensitive when used to test canine and equine blood DNA samples spiked with known amounts of synthetic DNA (gBlock) control template. The assays were specific, as evidenced by lack of cross reaction to non-target gBlock or other pathogens commonly tested in veterinary diagnostic labs. With appropriate Ct cutoff values for positive samples and negative controls and the melting temperature (TM) ranges established in the present study, the QPCR panel is suitable for accurate, convenient and rapid screening and confirmation of tick-borne pathogens in animals.

Molecular confirmation of Hepatozoon canis in Mauritius

In this study, Hepatozoon species was molecularly identified and characterized for the first time on the Indian Ocean island of Mauritius. Partial sequences of the 18S rRNA gene of the Hepatozoon isolates were analysed from three naturally infected dogs. The sequences of H. canis were similar to the 18S rRNA partial sequences (JX112783, AB365071 99%) from dog blood samples from West Indies and Nigeria. Our sequences were deposited in the GenBank database.

Babesia microti infection and hemophagocytic lymphohistiocytosis in an immunocompetent patient

Babesiosis is a rare and potentially severe tick-borne illness endemic to the Northeastern and upper Midwestern regions of the USA. Hemophagocytic lymphohistiocytosis is an uncommon condition resulting from over-activation of the immune system. The first known case of babesiosis and hemophagocytic lymphohistiocytosis in an immunocompetent patient is reported here.

Microbiota of field-collected Ixodes scapularis and Dermacentor variabilis from eastern and southern Ontario, Canada

The microbiota of hard ticks has been an area of growing interest due to the potential role that the broader microbial community may play in pathogen carriage and transmission. In the last two decades, Ontario, Canada has experienced rapid changes in the risk of tick-borne disease, primarily due to the range expansion of Ixodes scapularis. Another human-biter, Dermacentor variabilis, is a longstanding resident of the province, but currently poses minimal risk of pathogen transmission. To examine the microbiota of these two species, we collected adult and nymphal I. scapularis and D. variabilis from the eastern and southern regions of the province via tick dragging, and conducted next generation sequencing of 19 samples (composed of 45 ticks) via Illumina MiSeq. A total of 1400469 sequences were detected (median 69118/sample; range 23350-155227). The most abundant families of bacteria were unclassified Clostridiales and Ruminococcaceae for both I. scapularis and D. variabilis. No significant differences in the relative abundances of any phylum, class, order, family or genus were detected between locations (east vs south), sex, life stage or tick species. There were no differences in community membership or structure based on unifrac and AMOVA analyses. Female and male ticks had lower microbial diversity when compared to nymphs, based on the Simpson's index and Shannon evenness index. The findings of our study differ from previous studies of these tick species conducted in other geographic areas, and highlight the potential role geography and related ecological factors may have in shaping the tick microbiota.

Five cases of vector-borne Francisella tularensis holarctica infections in south-western Germany and genetic diversity

Tularemia is a rare zoonotic disease in Germany. Francisella tularensis has been isolated previously from ticks in southern Germany underscoring the importance of ticks (Ixodes ricinus) in tularemia transmission, but there have been only few reports from this region with single cases or small case series of tick-borne transmissions of tularemia. We report five cases of non-game animal associated tularemia diagnosed from 2010 to 2016 in southwestern Germany - Baden-Wuerttemberg. Our case series and molecular typing (MLVA) results add published clinical experience to this underdiagnosed disease and consolidate previous findings regarding tick-borne transmission of tularemia and phylogenetic diversity in Germany.

Major vectors and vector-borne diseases in small ruminants in Ethiopia: A systematic review

Vector-borne diseases are among major health constraints of small ruminant in Ethiopia. While various studies on single vector-borne diseases or presence of vectors have been conducted, no summarized evidence is available on the occurrence of these diseases and the related vectors. This systematic literature review provides a comprehensive summary on major vectors and vector-borne diseases in small ruminants in Ethiopia. Search for published and unpublished literature was conducted between 8th of January and 25th of June 2015. The search was both manual and electronic. The databases used in electronic search were PubMed, Web of Science, CAB Direct and AJOL. For most of the vector-borne diseases, the summary was limited to narrative synthesis due to lack of sufficient data. Meta-analysis was computed for trypanosomosis and dermatophilosis while meta-regression and sensitivity analysis was done only for trypanososmosis due to lack of sufficient reports on dermatophilosis. Owing emphasis to their vector role, ticks and flies were summarized narratively at genera/species level. In line with inclusion criteria, out of 106 initially identified research reports 43 peer-reviewed articles passed the quality assessment. Data on 7 vector-borne diseases were extracted at species and region level from each source. Accordingly, the pooled prevalence estimate of trypanosomosis was 3.7% with 95% confidence interval (CI) 2.8, 4.9), while that of dermatophilosis was 3.1% (95% CI: 1.6, 6.0). The in-between study variance noted for trypanosomosis was statistically significant (p<0.05). Among the three covariates considered for meta-regression, only one (species) fitted the final model significantly (p<0.05) and explained 65.44% of the between studies variance (R²). The prevalence in sheep (5.5%) increased nearly by 34% compared to goats (2.9%). The parasitic presence in blood was documented for babesiosis (3.7% in goats); and anaplasmosis (3.9% in sheep). Serological evidence was retrieved for bluetongue ranging from 34.1% to 46.67% in sheep, and coxiellosis was 10.4% in goats. There was also molecular evidence on the presence of theileriosis in sheep (93%, n=160) and goats (1.9%, n=265). Regarding vectors of veterinary importance, 14 species of ticks in five genera, four species of Glossina and 4 genera of biting flies were reported. Despite the evidence on presence of various vectors including ticks, flies, mosquitoes and midges, studies on vector-borne diseases in Ethiopia are surprisingly rare, especially considering risks related to climate change, which is likely to affect distribution of vectors. Thus better evidence on the current situation is urgently needed in order to prevent spread and to model future distribution scenarios.

Babesiosis in Long Island: review of 62 cases focusing on treatment with azithromycin and atovaquone

BACKGROUND

Babesiosis is a potentially life-threatening, tick-borne infection endemic in New York. The purpose of this study was to review recent trends in babesiosis management and outcomes focusing on patients, who were treated with combination of azithromycin and atovaquone.

METHODS

A retrospective chart review of patients seen at Stony Brook University Hospital between 2008 and 2014 with peripheral blood smears positive for Babesia was performed. Clinical and epidemiological information was recorded and analyzed.

RESULTS

62 patients had confirmed babesiosis (presence of parasitemia). Forty six patients (74%) were treated exclusively with combination of azithromycin and atovaquone; 40 (87%) of these patients were hospitalized, 11 (28%) were admitted to Intensive Care Unit (ICU), 1 (2%) died. Majority of patients presented febrile with median temperature 38.5 °C. Median peak parasitemia among all patients was 1.3%, and median parasitemia among patients admitted to ICU was 5.0%. Six patients (15%) required exchange transfusion. Majority of patients (98%) improved and were discharged from hospital or clinic.

CONCLUSION

Symptomatic babesiosis is still rare even in endemic regions. Recommended treatment regimen is well tolerated and effective. Compared to historical controls we observed a lower overall mortality.

Genetic profiling for Anaplasma and Ehrlichia species in ticks collected in the Eastern Cape Province of South Africa

Background

Anaplasma and Ehrlichia are emerging tick-borne pathogens that cause anaplasmosis and ehrlichiosis in humans and other animals worldwide. Infections caused by these pathogens are deadly if left untreated. There has been relatively no systematic survey of these pathogens among ticks in South Africa, thus necessitating this study. The presence of Anaplasma and Ehrlichia species were demonstrated by PCR in ticks collected from domestic ruminants at some selected communities in the Eastern Cape of South Africa. The ticks were identified by morphological characteristics and thereafter processed to extract bacterial DNA, which was analyzed for the presence of genetic materials of Anaplasma and Ehrlichia.

Results

Three genera of ticks comprising five species were identified. The screening yielded 16 positive genetic materials that were phylogenetically related to Ehrlichia sequences obtained from GenBank, while no positive result was obtained for Anaplasma. The obtained Ehrlichia sequences were closely related to E. chaffeensis, E. canis, E. muris and the incompletely described Ehrlichia sp. UFMG-EV and Ehrlichia sp. UFMT.

Conclusion

The findings showed that ticks in the studied areas were infected with Ehrlichia spp. and that the possibility of transmission to humans who might be tick infested is high.

"Candidatus anaplasma camelii" in one-humped camels (Camelus dromedarius) in Morocco: a novel and emerging anaplasma species?

Background

There has been a growing interest in camel anaplasmosis due to its recent emergence in this reservoir species and concerns for its zoonotic potential. The epidemiology of anaplasmosis in camels therefore remains poorly understood mostly because camels belong to marginalised poor and often transhumant populations whose interests are largely neglected. Most studies of anaplasmosis in camels have relied on microscopy and serology for diagnosis and only three studies, undertaken in Tunisia, Saudia Arabia and China, have used molecular diagnostics. The present work characterises Anaplasmataceae strains circulating in the Camelus dromedarius reservoir in Morocco using PCR.

Methods

Camels (n = 106) were randomly sampled from 6 regions representing different agro-ecological areas in southern Morocco. Whole blood was collected and screened using PCR methods targeting the gene groEL. Anaplasmataceae strains were characterised by sequence analysis of the gene groEL.

Results

A total of 39.62% (42/106) camels screened were positive for Anaplasmataceae spp. GenBank BLAST analysis of five positive sequenced samples revealed that all strains were 100% identical to “Candidatus Anaplasma camelii”. Phylogenetic investigation and genetic characterisation of the aligned segment (650 bp) of the gene groEL confirmed high similarity with A. platys.

Conclusion

This study demonstrates the circulation of a previously unidentified species of the genus Anaplasma in Morocco which is genetically close to the agent causing canine anaplasmosis but whose main reservoir is thought to be Camelus dromedarius.

Trial registration number

This study is not a clinical trial and therefore a trial registration number does not apply.

Electronic supplementary material

The online version of this article (doi:10.1186/s40249-016-0216-8) contains supplementary material, which is available to authorized users.

Is there a Lyme-like disease in Australia? Summary of the findings to date

Lyme Borreliosis is a common tick-borne disease of the northern hemisphere caused by the spirochaetes of the Borrelia burgdorferi sensu lato (B. burgdorferi s. l.) complex. It results in multi-organ disease with arthritic, cardiac, neurological and dermatological manifestations. In the last twenty-five years there have been over 500 reports of an Australian Lyme-like syndrome in the scientific literature. However, the diagnoses of Lyme Borreliosis made in these cases have been primarily by clinical presentation and laboratory results of tentative reliability and the true cause of these illnesses remains unknown. A number of animals have been introduced to Australia that may act as B. burgdorferi s. l. reservoirs in Lyme-endemic countries, and there are some Australian Ixodes spp. and Haemaphysalis spp. ticks whose geographical distribution matches that of the Australian Lyme-like cases. Four published studies have searched for Borrelia in Australian ticks, with contradicting results. The cause of the potential Lyme-like disease in Australia remains to be defined. The evidence to date as to whether these illnesses are caused by a Borrelia species, another tick borne pathogen or are due to a novel or unrelated aetiology is summarised in this review.

A chronological review of experimental infection studies of the role of wild animals and livestock in the maintenance and transmission of Crimean-Congo hemorrhagic fever virus

This article provides a definitive review of experimental studies of the role of wild animals and livestock in the maintenance and transmission of Crimean-Congo hemorrhagic fever virus (CCHFV), the etiologic agent of Crimean-Congo hemorrhagic fever (CCHF), beginning with the first recognized outbreak of the human disease in Crimea in 1944. Published reports by researchers in the former Soviet Union, Bulgaria, South Africa, and other countries where CCHF has been observed show that CCHFV is maintained in nature in a tick-vertebrate-tick enzootic cycle. Human disease most commonly results from the bite of an infected tick, but may also follow crushing of infected ticks or exposure to the blood and tissues of infected animals during slaughter. Wild and domestic animals are susceptible to infection with CCHFV, but do not develop clinical illness. Vertebrates are important in CCHF epidemiology, as they provide blood meals to support tick populations, transport ticks across wide geographic areas, and transmit CCHFV to ticks and humans during the period of viremia. Many aspects of vertebrate involvement in the maintenance and spread of CCHFV are still poorly understood. Experimental investigations in wild animals and livestock provide important data to aid our understanding of CCHFV ecology. This article is the second in a series of reviews of more than 70 years of research on CCHF, summarizing important findings, identifying gaps in knowledge, and suggesting directions for future research.

Emerging borreliae - Expanding beyond Lyme borreliosis

Lyme borreliosis (or Lyme disease) has become a virtual household term to the exclusion of other forgotten, emerging or re-emerging borreliae. We review current knowledge regarding these other borreliae, exploring their ecology, epidemiology and pathological potential, for example, for the newly described B. mayonii. These bacteria range from tick-borne, relapsing fever-inducing strains detected in some soft ticks, such as B. mvumii, to those from bat ticks resembling B. turicatae. Some of these emerging pathogens remain unnamed, such as the borrelial strains found in South African penguins and some African cattle ticks. Others, such as B. microti and unnamed Iranian strains, have not been recognised through a lack of discriminatory diagnostic methods. Technical improvements in phylogenetic methods have allowed the differentiation of B. merionesi from other borrelial species that co-circulate in the same region. Furthermore, we discuss members that challenge the existing dogma that Lyme disease-inducing strains are transmitted by hard ticks, whilst the relapsing fever-inducing spirochaetes are transmitted by soft ticks. Controversially, the genus has now been split with Lyme disease-associated members being transferred to Borreliella, whilst the relapsing fever species retain the Borrelia genus name. It took some 60 years for the correlation with clinical presentations now known as Lyme borreliosis to be attributed to their spirochaetal cause. Many of the borreliae discussed here are currently considered exotic curiosities, whilst others, such as B. miyamotoi, are emerging as significant causes of morbidity. To elucidate their role as potential pathogenic agents, we first need to recognise their presence through suitable diagnostic approaches.

In vitro antiviral activity of adenosine analog NITD008 against tick-borne flaviviruses

There are currently no antiviral therapies available for the tick-borne flaviviruses associated with hemorrhagic fevers: Kyasanur Forest disease virus (KFDV), both classical and the Alkhurma hemorrhagic fever virus (AHFV) subtype, and Omsk hemorrhagic fever virus (OHFV). In this brief study, we describe the in vitro antiviral activity of adenosine analog NITD008 against KFDV, AHFV, OHFV, as well as Tick-borne Encephalitis virus (TBEV). Alongside the well-established activity of NITD008 against mosquito-borne flaviviruses, our results have demonstrated the feasibility of identifying nucleoside analog inhibitors that have pan-flavivirus activity.

Development of pan-phlebovirus RT-PCR assay

This study reports the pan-phlebovirus assay capable of detecting both sandfly/mosquito- and tick-borne phleboviruses. Sensitivity and specificity of the assay was verified using a panel of arboviruses. The RT-PCR assay is simple and sensitive, and thus well suited for screening of field samples.

Increased working memory related fMRI signal in children following Tick Borne Encephalitis

OBJECTIVE

Tick Borne Encephalitis (TBE) is a viral infection in the central nervous system endemic in Europe and Asia. While pediatric infection may carry a lower risk for serious neurological sequelae compared to adults, a large proportion of children experience long term cognitive problems, most markedly decreased working memory capacity. We explored whether task related functional magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI) could reveal a biological correlate of status-post TBE in children.

METHODS

We examined 11 serologically verified pediatric TBE patients with central nervous system involvement with 55 healthy controls with working memory tests and MRI.

RESULTS

The TBE patients showed a prominent deficit in working memory capacity and an increased task related functional MRI signal in working memory related cortical areas during a spatial working memory task performed without sedation. No diffusion differences could be found with DTI, in line with the reported paucity of anatomical abnormalities.

CONCLUSION

This study is the first to demonstrate functional MRI abnormalities in TBE patients that bears similarity to other patient groups with diffuse neuronal damage.

Natural history of Zoonotic Babesia: Role of wildlife reservoirs

Babesiosis is an emerging zoonotic disease on all inhabited continents and various wildlife species are the principal reservoir hosts for zoonotic Babesia species. The primary vectors of Babesia are Ixodid ticks, with the majority of zoonotic species being transmitted by species in the genus Ixodes. Species of Babesia vary in their infectivity, virulence and pathogenicity for people. Various factors (e.g., increased interactions between people and the environment, increased immunosuppression, changes in landscape and climate, and shifts in host and vector species abundance and community structures) have led to an increase in tick-borne diseases in people, including babesiosis. Furthermore, because babesiosis is now a reportable disease in several states in the United States, and it is the most common blood transfusion-associated parasite, recognized infections are expected to increase. Because of the zoonotic nature of these parasites, it is essential that we understand the natural history (especially reservoirs and vectors) so that appropriate control and prevention measures can be implemented. Considerable work has been conducted on the ecology of Babesia microti and Babesia divergens, the two most common causes of babesiosis in the United States and Europe, respectively. However, unfortunately, for many of the zoonotic Babesia species, the reservoir(s) and/or tick vector(s) are unknown. We review the current knowledge regarding the ecology of Babesia among their reservoir and tick hosts with an emphasis of the role on wildlife as reservoirs. We hope to encourage the molecular characterization of Babesia from potential reservoirs and vectors as well from people. These data are necessary so that informed decisions can be made regarding potential vectors and the potential role of wildlife in the ecology of a novel Babesia when it is detected in a human patient.

The lipoprotein La7 contributes to Borrelia burgdorferi persistence in ticks and their transmission to naïve hosts

La7, an immunogenic outer membrane lipoprotein of Borrelia burgdorferi, produced during infection, has been shown to play a redundant role in mammalian infectivity. Here we show that La7 facilitates pathogen survival in all tested phases of the vector-specific spirochete life cycle, including tick-to-host transmission. Unlike wild type or la7-complemented isolates, isogenic La7-deficient spirochetes are severely impaired in their ability to persist within feeding ticks during acquisition from mice, in quiescent ticks during larval-nymphal inter-molt, and in subsequent pathogen transmission from ticks to naïve hosts. Analysis of gene expression during the major stages of the tick-rodent infection cycle showed increased expression of la7 in the vector and a swift downregulation in the mammalian hosts. Co-immunoprecipitation studies coupled with liquid chromatography-mass spectrometry analysis further suggested that La7, a highly conserved and abundant inner membrane protein, is involved in protein-protein interaction with a discrete set of borrelial ligands although biological significance of such interactions remains unclear. Further characterization of vector-induced membrane antigens like La7 and its interacting partners will likely aid in our understanding of the molecular details of B. burgdorferi persistence and transmission through a complex enzootic cycle.