Treatment Of Tick-borne Diseases Research Articles

What a Tick Can Tell a Doctor: Using the Human-Biting Tick in the Clinical Management of Tick-Borne Disease.

With expanding concern about ticks, there is a general sense of uncertainty about the diagnosis and treatment of tick-borne diseases. The diagnosis process is often based on clinical judgment in conjunction with laboratory testing and can be pathogen specific. Treatments may require disease-dependent approaches, and co-infections complicate or increase the severity of the clinical picture. Measuring exposure indices in the tick has become popular among providers and their patients, though this practice is not universally understood, and certain public health agencies have voiced concerns regarding interpretation and rigor of testing. As many providers subscribe to or recommend these services to aid in pretest risk and exposure assessments, this work sought to clarify the role of pathogen testing human-biting ticks as a complement to the diagnostic pipeline and raises points that must be addressed through future research and interdisciplinary conversation. Future work is needed to develop quality control oversight for tick testing laboratories. Studies on the integration of tick testing with human cases to see how these services affect health outcomes are also needed. Alongside these, improvements in the quality and availability of diagnostics are of critical importance.

Identification of Amblyomma javanense and detection of tick-borne Ehrlichia spp. in confiscated Malayan Pangolins.

Due to habitat destruction and illegal hunting and trade, the number of pangolins has been sharply reduced. To protect pangolins from extinction, relevant departments are combined and active action have been taken. A total of 21 confiscated Malayan pangolins were rescued in 2019, but died continuously for unknown reasons. This study aimed to investigate the reasons for the death of these pangolin and rescue them. 19 of the 21 confiscated pangolins had ticks on their body integument. A total of 303 ticks were collected and identified as Amblyomma javanense (A. javanense) according to their morphology and the sequences of 16S rRNA and internal transcribed spacer 2 (ITS2). There were multi-organ damages in the dead pangolins, especially congestion and hemorrhage in lung, heart and kidney and inflammation of which were observed using HE staining. Pathogens' nucleic acid detection showed ticks were only positive for Ehrlichia spp, with 56.7% positive rate of collected ticks (127/224), which was further confirmed in tissues from dead pangolins. Our findings confirm that ehrlichiosis caused by Ehrlichia spp. from A. javanense might accelerate the confiscated pangolin's death. More attention should be payed to tick-elimination work and the diagnoses and treatment of tick-borne diseases in the follow-up rescue operation.

Ethnoveterinary medicinal plants application for the treatment of tick-borne diseases in cattle around the Eastern Cape Province of South Africa

Background: South Africa is recognised as one of the most biodiverse countries in terms of fauna and flora in the sub-Saharan region. More than 40% of farmers in remote rural areas of the Eastern Cape Province use medicinal plants for the treatment of different livestock ailments. Aim: The aim of the study was to identify and document plant species used for the treatment of tick-borne diseases in the Amathole and O.R. Tambo district municipalities of the Eastern Cape, South Africa. Methods: Semi-structured questionnaire was employed to obtain detailed information of ethnoveterinary medicinal plants used including parts, mode of preparation and mode of administration from 48 respondents between November 2013 and February 2014. The collected plant species were identified scientifically at the Stutterheim Dohne Herbarium, where voucher numbers were obtained and herbarium specimens were deposited. Data collected were subjected to descriptive statistical analysis. Results: A total of nine medicinal plant species belonging to eight families and represented by nine genera were identified. The most dominant inhabitants were trees (55.6%), followed by herbs (33.3%) and shrubs (11.1%). The most frequently used plant families for tick-borne diseases were Xanthorrhoeaceae, Ebenaceae, Proteaceae, Malvaceae, Asteraceae, Vitaceae, Loganiaceae and Iridaceae, and from these plant families, leaves (44.4%) were the most commonly used plant parts. Conclusion: The data display that people in rural areas have preserved some knowledge of ethnoveterinary practices for the treatment of tick-borne diseases. However, further studies on plants used for the treatment of tick-borne diseases can be advanced towards validation and standardisation by evaluating parameters such as efficacy, safety and toxicity, quality (phytochemicals) and dosage standards.

Antibiotic Treatment Response in Chronic Lyme Disease: Why Do Some Patients Improve While Others Do Not?

There is considerable uncertainty regarding treatment of Lyme disease patients who do not respond fully to initial short-term antibiotic therapy. Choosing the best treatment approach and duration remains challenging because treatment response among these patients varies: some patients improve with treatment while others do not. A previous study examined treatment response variation in a sample of over 3500 patients enrolled in the MyLymeData patient registry developed by LymeDisease.org (San Ramon, CA, USA). That study used a validated Global Rating of Change (GROC) scale to identify three treatment response subgroups among Lyme disease patients who remained ill: nonresponders, low responders, and high responders. The present study first characterizes the health status, symptom severity, and percentage of treatment response across these three patient subgroups together with a fourth subgroup, patients who identify as well. We then employed machine learning techniques across these subgroups to determine features most closely associated with improved patient outcomes, and we used traditional statistical techniques to examine how these features relate to treatment response of the four groups. High treatment response was most closely associated with (1) the use of antibiotics or a combination of antibiotics and alternative treatments, (2) longer duration of treatment, and (3) oversight by a clinician whose practice focused on the treatment of tick-borne diseases.

1338. Development of a Novel Application for Differential Diagnosis of Tick-borne Diseases

BackgroundEarly diagnosis and treatment of tick-borne diseases (TBDs) is critical for mitigating their adverse health outcomes, but the differential diagnosis of TBDs is challenging because many symptoms are nonspecific and commonly used diagnostic assays have significant shortcomings. Furthermore, although the local incidence of TBDs is recognized as an important factor in diagnosis, tools to help clinicians formally consider surveillance data in their decision-making are not available. To address these gaps, Gryphon Scientific developed a differential diagnosis application (app) for TBDs that calculates a patient’s likelihood of infection with specific TBDs based on their symptoms, risk factors, and state of suspected tick exposure.MethodsA differential diagnosis model for TBDs was developed using data on: (1) TBD symptom and risk factor prevalence in TBD patient populations, collected from clinical studies; and (2) human TBD incidence data from notifiable disease surveillance systems and tick infection prevalence data from reports and public databases, which were combined to develop an environmental risk measure. These data were used to build a Bayesian Belief Network (BBN) model that predicts TBD infection probabilities based on a patient’s symptoms, risk factors, and state of suspected tick exposure. Performance of the model was validated using case studies from the biomedical literature. The model was incorporated into an app developed using R-shiny, called TBD-DDx (Figures 1 and 3).ResultsA pilot application was developed that includes 10 states (AR, CT, MA, ME, MN, MO, NH, RI, VT, and WI) and the 11 TBDs endemic to those states. The differential diagnosis model identified the patient’s true disease as the top-predicted disease in 56% of cases and within the top three predicted TBD in 84% of cases. The inclusion of incidence factors in the model improved performance (Figure 4).ConclusionThese results demonstrate that the TBD-DDx app is a promising tool for informing clinical diagnoses of TBDs to guide selection of diagnostic testing and treatment. This study represents the first use of a BBN modeling approach that incorporates an environmental risk measure and could be adapted for differential diagnosis of other diseases with environmental or other exposure risks. Disclosures All authors: No reported disclosures.

Multiple infections in questing nymphs and adult female Ixodes ricinus ticks collected in a recreational forest in Denmark

During its lifecycle, the generalist Ixodes ricinus takes up three blood meals from a wide selection of vertebrate hosts, some of which are reservoirs for multiple vector-associated pathogens. Since I. ricinus also readily bites humans, pets, and livestock, these hosts are at risk of becoming infected with more than one tick-borne pathogen. Multiple tick-borne infections are a public health concern, since they may increase diversity and duration of symptoms and complicate differential diagnosis and therapy. We used an existing Fluidigm real-time PCR chip to identify the minimum risk of exposure to infected/co-infected ticks in Denmark. We screened 509 nymphs and 504 adult female I. ricinus ticks for 17 different vector-associated pathogenic agents. The questing ticks were collected by flagging during the same season in two consecutive years in Grib forest in the capital region of Copenhagen. Overall, 19.1% of the nymphs and 52.2% of the adult female ticks harbored at least one zoonotic pathogen. The main agents were Borrelia spp., Anaplasma phagocytophilum and Rickettsia helvetica, while Candidatus Neoehrlichia mikurensis and Babesia venatorum both were present in less than 1% of the ticks. In 3.5% of the nymphs and 12.3% of adults we found more than one tick-borne pathogen. Of these, 15% were potentially triple or quadruple infections. Whereas mixed infections with Borrelia were equally distributed among both life stages, the adult ticks hosted 84.5% of the co-infections with different species of tick-borne pathogens, chiefly involving Borrelia species in combination with either R. helvetica or A. phagocytophilum. Statistical analyses indicated non-random co-occurrence of Borrelia spielmanii/Borrelia garinii in both life stages and B. garinii/Borrelia afzelii and B. garinii/Borrelia valaisiana in the nymphs. Although the overall prevalence of ticks hosting more than one infection only constituted 7.9% at the particular site investigated in this study, our results still underline that co-infections should be considered in diagnosis and treatment of tick-borne diseases in northern Europe.

Tick distribution along animal tracks: implication for preventative medicine.

Tick abundance and the prevalence of the pathogens they carry have been increasing worldwide in the last decades, and is projected to increase even further. Despite the fact that problem is global, there still remain many gaps in the diagnosis and treatment of tick-borne diseases. The best protection from tick-borne pathogens, therefore, is prevention and avoidance of bites. Ticks mobility is limited so that their spatial distribution is strongly correlated with the presence of, especially with large mammals. In this study, the hypothesis was tested that tick abundance is higher on animal tracks in the forests than in adjacent habitats. This is an important issue because there are still several human habits and practices that can decrease the zoonoses risk. For example, during recreation in forest, people should always walk on the paths (including narrow animal's tracks) instead of wading through bushes. Flagging of animal trails and near control transects were performed simultaneously. Next, collected ticks were counted, sexed and aged. The abundance of ticks was almost 5-fold (Ixodes ricinus) and 3-fold (Dermacentor spp.) higher on animal trails than on adjacent control transects. The results obtained support the hypothesis that ticks are more abundant on pathways than in adjacent habitats. Most likely, the pattern emerges because large mammals, like deer, which are the most important ticks hosts, use forest paths to move across the landscape and frequently move along the same routes. This research sends an important public message that these forest trails are hotspots of disease risk and should be avoided.

Ixodes ricinus immunogenic saliva protein, homologue to Amblyomma americanum AV422: Determining its potential for use in tick bite confirmation

Tick bites often go unnoticed, so specific reliable tests are needed to confirm them for prompt diagnosis and treatment of tick-borne diseases. One of the promising candidates for developing such a test is AV422, a tick saliva protein that has been conserved across tick genera. In this study, we demonstrate the potential of the AV422 homologue from Ixodes ricinus to be used for tick bite detection for both Prostriata and Metastriata. We expressed recombinant (r) I. ricinus (Ir) AV422 in E. coli and subjected it to Western blot analysis using rat antibodies to saliva proteins of both I. ricinus (Prostriata) and Dermacentor reticulatus (Metastriata) larvae. Our data demonstrate that rIrAV422 specifically bound to antibodies from sera of rats used for both I. ricinus and D. reticulatus larvae feeding, but not to antibodies from control serum, emphasizing its specificity since tick bites were the sole cause of sera reactivity.

Molecular detection of Theileria, Babesia, and Hepatozoon spp. in ixodid ticks from Palestine

Ixodid ticks transmit various infectious agents that cause disease in humans and livestock worldwide. A cross-sectional survey on the presence of protozoan pathogens in ticks was carried out to assess the impact of tick-borne protozoa on domestic animals in Palestine. Ticks were collected from herds with sheep, goats and dogs in different geographic districts and their species were determined using morphological keys. The presence of piroplasms and Hepatozoon spp. was determined by PCR amplification of a 460–540bp fragment of the 18S rRNA gene followed by RFLP or DNA sequencing. A PCR-RFLP method based on the 18S rRNA was used in order to detect and to identify Hepatozoon, Babesia and Theileria spp. A total of 516 ticks were collected from animals in six Palestinian localities. Five tick species were found: Rhipicephalus sanguineus sensu lato, Rhipicephalus turanicus, Rhipicephalus bursa, Haemaphysalis parva and Haemaphysalis adleri. PCR-based analyses of the ticks revealed Theileria ovis (5.4%), Hepatozoon canis (4.3%), Babesia ovis (0.6%), and Babesia vogeli (0.4%). Theileria ovis was significantly associated with ticks from sheep and with R. turanicus ticks (p<0.01). H. canis was detected only in R. sanguineus s.l. and was significantly associated with ticks from dogs (p<0.01).To our knowledge, this is the first report describing the presence of these pathogens in ticks collected from Palestine. Communicating these findings with health and veterinary professionals will increase their awareness, and contribute to improved diagnosis and treatment of tick-borne diseases.

Ethnoecological knowledge of ticks and treatment of tick-borne diseases among Maasai people in Northern Tanzania.

Aim:The aim of this study was to understand traditional knowledge of tick ecology and remedies for tick-borne diseases (TBDs) among the Maasai people in northern Tanzania.Materials and Methods:Semi-structured interviews were conducted among specific groups likely to be knowledgeable about tick ecology and TBDs in livestock among the Maasai people.Results:A total of 25 plant species belonging to 18 families were used to treat 8 different TBDs of livestock. Most of the plant species used were of Fabaceae and Burseraceae families. Aloe volkensii, Cissus grandifolia, and Terminalia brownii were the most commonly used plant species. The major plant growth form used was trees, while stems and bark were the main plant parts used. Most treatments were taken orally.Conclusion:Maasai people have substantial knowledge on tick ecology exemplified by their ability to differentiate between different tick species and the range of remedies for each of the TBDs. Because traditional ethnoveterinary remedies are frequently utilized, their effectiveness should be further investigated.

Diagnosis and Treatment of Tick-Borne Diseases in Horses

Diagnosis and Treatment of Tick-Borne Diseases in Horses

Distribution of tick-borne diseases in China

As an important contributor to vector-borne diseases in China, in recent years, tick-borne diseases have attracted much attention because of their increasing incidence and consequent significant harm to livestock and human health. The most commonly observed human tick-borne diseases in China include Lyme borreliosis (known as Lyme disease in China), tick-borne encephalitis (known as Forest encephalitis in China), Crimean-Congo hemorrhagic fever (known as Xinjiang hemorrhagic fever in China), Q-fever, tularemia and North-Asia tick-borne spotted fever. In recent years, some emerging tick-borne diseases, such as human monocytic ehrlichiosis, human granulocytic anaplasmosis, and a novel bunyavirus infection, have been reported frequently in China. Other tick-borne diseases that are not as frequently reported in China include Colorado fever, oriental spotted fever and piroplasmosis. Detailed information regarding the history, characteristics, and current epidemic status of these human tick-borne diseases in China will be reviewed in this paper. It is clear that greater efforts in government management and research are required for the prevention, control, diagnosis, and treatment of tick-borne diseases, as well as for the control of ticks, in order to decrease the tick-borne disease burden in China.

Strategies, Effectiveness and Rationale of Vector-borne Disease Control in the Pastoralist System of South-western Uganda

In Uganda, control of vector-borne diseases is mainly in form of vector control, and chemotherapy. There have been reports that acaricides are being misused in the pastoralist systems in Uganda. This is because of the belief by scientists that intensive application of acaricide is uneconomical and unsustainable particularly in the indigenous cattle. The objective of this study was to investigate the strategies, rationale and effectiveness of vector-borne disease control by pastoralists. To systematically carry out these investigations, a combination of qualitative and quantitative research methods was used, in both the collection and the analysis of data. Cattle keepers were found to control tick-borne diseases (TBDs) mainly through spraying, in contrast with the control of trypanosomosis for which the main method of control was by chemotherapy. The majority of herders applied acaricides weekly and used an acaricide of lower strength than recommended by the manufacturers. They used very little acaricide wash, and spraying was preferred to dipping. Furthermore, pastoralists either treated sick animals themselves or did nothing at all, rather than using veterinary personnel. Oxytetracycline (OTC) was the drug commonly used in the treatment of TBDs. Nevertheless, although pastoralists may not have been following recommended practices in their control of ticks and tick-borne diseases, they were neither wasteful nor uneconomical and their methods appeared to be effective. Trypanosomosis was not a problem either in Sembabule or Mbarara district. Those who used trypanocides were found to use more drugs than were necessary.

An update on Lyme disease and other tick-borne illnesses.

Lyme disease, the most common vector-borne illness in North America, is a multisystem, multistage infectious disease caused by the tick-transmitted spirochete Borrelia burgdorferi. Although Lyme disease is not fatal, it can cause musculoskeletal, neurological, and cardiovascular manifestations that may be difficult to treat. Clinicians must also be aware of other potentially fatal tick-borne diseases such as babesiosis, ehrlichiosis, and Rocky Mountain spotted fever. Early identification and treatment of tick-borne diseases are crucial to preventing devastating sequelae.

Species of the Rhipicephalus sanguineus group: relationship and genetic differentiation

Ixodid ticks transmit various infectious agents that cause disease in humans and livestock worldwide. A cross-sectional survey on the presence of protozoan pathogens in ticks was carried out to assess the impact of tick-borne protozoa on domestic animals in Palestine. Ticks were collected from herds with sheep, goats and dogs in different geographic districts and their species were determined using morphological keys. The presence of piroplasms and Hepatozoon spp. was determined by PCR amplification of a 460–540 bp fragment of the 18S rRNA gene followed by RFLP or DNA sequencing. A PCR-RFLP method based on the 18S rRNA was used in order to detect and to identify Hepatozoon, Babesia and Theileria spp. A total of 516 ticks were collected from animals in six Palestinian localities. Five tick species were found: Rhipicephalus sanguineus sensu lato, Rhipicephalus turanicus, Rhipicephalus bursa, Haemaphysalis parva and Haemaphysalis adleri. PCR-based analyses of the ticks revealed Theileria ovis (5.4%), Hepatozoon canis (4.3%), Babesia ovis (0.6%), and Babesia vogeli (0.4%). Theileria ovis was significantly associated with ticks from sheep and with R. turanicus ticks (p < 0.01). H. canis was detected only in R. sanguineus s.l. and was significantly associated with ticks from dogs (p < 0.01).To our knowledge, this is the first report describing the presence of these pathogens in ticks collected from Palestine. Communicating these findings with health and veterinary professionals will increase their awareness, and contribute to improved diagnosis and treatment of tick-borne diseases.