Prevention Of Lyme Disease Research Articles

Community Partnership Designed to Promote Lyme Disease Prevention and Engagement in Citizen Science.

The goal of this project is to promote Lyme disease prevention and to cultivate an interest in science through a citizen-science project coordinated by researchers at a public university and teachers at rural high schools. The lesson plan is designed to increase student interest in pursuing a science career through participation in an authentic research experience, utilizing a topic that has implications on the health of the surrounding community. Students are introduced in the classroom to zoonotic diseases transmitted by the Ixodes tick, the health risks of Lyme disease, and disease prevention strategies. Students then participate in a research experience collecting field data and ticks from their community, which are used in university research. To measure changes in student knowledge and attitudes toward Lyme disease and science careers, students completed surveys related to the learning objectives associated with the experience. We found participation in the activity increased student confidence and ability to correctly differentiate a deer tick from a wood tick and to recognize the symptoms of Lyme disease. In addition, students reported increased interest in pursuing a science degree in college or graduate school. Authentic research experience related to a disease relevant to the local community is effective at enhancing high school student engagement in science.

Will Culling White-Tailed Deer Prevent Lyme Disease?

White-tailed deer play an important role in the ecology of Lyme disease. In the United States, where the incidence and geographic range of Lyme disease continue to increase, reduction of white-tailed deer populations has been proposed as a means of preventing human illness. The effectiveness of this politically sensitive prevention method is poorly understood. We summarize and evaluate available evidence regarding the effect of deer reduction on vector tick abundance and human disease incidence. Elimination of deer from islands and other isolated settings can have a substantial impact on the reproduction of blacklegged ticks, while reduction short of complete elimination has yielded mixed results. To date, most studies have been conducted in ecologic situations that are not representative to the vast majority of areas with high human Lyme disease risk. Robust evidence linking deer control to reduced human Lyme disease risk is lacking. Currently, there is insufficient evidence to recommend deer population reduction as a Lyme disease prevention measure, except in specific ecologic circumstances.

Impact of Spring Bird Migration on the Range Expansion of Ixodes scapularis Tick Population.

Many observational studies suggest that seasonal migratory birds play an important role in spreading Ixodes scapularis, a vector of Lyme disease, along their migratory flyways, and they are believed to be responsible for geographic range expansion of I. scapularis in Canada. However, the interplay between the dynamics of I. scapularis on land and migratory birds in the air is not well understood. In this study, we develop a periodic delay meta-population model which takes into consideration the local landscape for tick reproduction within patches and the times needed for ticks to be transported by birds between patches. Assuming that the tick population is endemic in the source region, we find that bird migration may boost an already established tick population at the subsequent region and thus increase the risk to humans, or bird migration may help ticks to establish in a region where the local landscape is not appropriate for ticks to survive in the absence of bird migration, imposing risks to public health. This theoretical study reveals that bird migration plays an important role in the geographic range expansion of I. scapularis, and therefore our findings may suggest some strategies for Lyme disease prevention and control.

Discovery of Outer Surface Protein A-Specific Human Monoclonal Antibodies Reactive Against a Broad Range of Borrelia Species for the Prevention of Lyme Disease

Discovery of Outer Surface Protein A-Specific Human Monoclonal Antibodies Reactive Against a Broad Range of Borrelia Species for the Prevention of Lyme Disease

Adaptation and Evaluation of a Multi-Criteria Decision Analysis Model for Lyme Disease Prevention.

Designing preventive programs relevant to vector-borne diseases such as Lyme disease (LD) can be complex given the need to include multiple issues and perspectives into prioritizing public health actions. A multi-criteria decision aid (MCDA) model was previously used to rank interventions for LD prevention in Quebec, Canada, where the disease is emerging. The aim of the current study was to adapt and evaluate the decision model constructed in Quebec under a different epidemiological context, in Switzerland, where LD has been endemic for the last thirty years. The model adaptation was undertaken with a group of Swiss stakeholders using a participatory approach. The PROMETHEE method was used for multi-criteria analysis. Key elements and results of the MCDA model are described and contrasted with the Quebec model. All criteria and most interventions of the MCDA model developed for LD prevention in Quebec were directly transferable to the Swiss context. Four new decision criteria were added, and the list of proposed interventions was modified. Based on the overall group ranking, interventions targeting human populations were prioritized in the Swiss model, with the top ranked action being the implementation of a large communication campaign. The addition of criteria did not significantly alter the intervention rankings, but increased the capacity of the model to discriminate between highest and lowest ranked interventions. The current study suggests that beyond the specificity of the MCDA models developed for Quebec and Switzerland, their general structure captures the fundamental and common issues that characterize the complexity of vector-borne disease prevention. These results should encourage public health organizations to adapt, use and share MCDA models as an effective and functional approach to enable the integration of multiple perspectives and considerations in the prevention and control of complex public health issues such as Lyme disease or other vector-borne and zoonotic diseases.

Evolutionary aspects of emerging Lyme disease in Canada.

In North America, Lyme disease (LD) is a tick-borne zoonosis caused by the spirochete bacterium Borrelia burgdorferi sensu stricto, which is maintained by wildlife. Tick vectors and bacteria are currently spreading into Canada and causing increasing numbers of cases of LD in humans and raising a pressing need for public health responses. There is no vaccine, and LD prevention depends on knowing who is at risk and informing them how to protect themselves from infection. Recently, it was found in the United States that some strains of B. burgdorferi sensu stricto cause severe disease, whereas others cause mild, self-limiting disease. While many strains occurring in the United States also occur in Canada, strains in some parts of Canada are different from those in the United States. We therefore recognize a need to identify which strains specific to Canada can cause severe disease and to characterize their geographic distribution to determine which Canadians are particularly at risk. In this review, we summarize the history of emergence of LD in North America, our current knowledge of B. burgdorferi sensu stricto diversity, its intriguing origins in the ecology and evolution of the bacterium, and its importance for the epidemiology and clinical and laboratory diagnosis of LD. We propose methods for investigating associations between B. burgdorferi sensu stricto diversity, ecology, and pathogenicity and for developing predictive tools to guide public health interventions. We also highlight the emergence of B. burgdorferi sensu stricto in Canada as a unique opportunity for exploring the evolutionary aspects of tick-borne pathogen emergence.

Review of methods to prevent and reduce the risk of Lyme disease.

Cases of Lyme disease and areas with self-sustaining populations of vector ticks are increasing in Canada. This trend is expected to continue. Preventing Lyme disease will therefore become relevant to an increasing number of Canadians. To summarize methods for reducing the risk of tick bites and preventing transmission once a tick is feeding. A literature search was conducted to identify methods to reduce the risk of tick bites and the abundance of vector ticks, as well as the risk of becoming infected with the Lyme disease pathogen, Borrelia burgdorferi (BB), if bitten by a vector tick. Current approaches to reducing the risk of tick bites or preventing infection with BB once bitten are largely reliant on the individual. They include use of topical repellents, use of protective clothing, avoidance of risk areas and removing ticks soon (ideally within a day) after they attach. These methods are efficacious, but constrained by user adherence. Other approaches such as landscape modification or the use of acaricides to control ticks, have shown promise in other countries, but have not been widely adopted in Canada. Lyme disease will continue to present a threat in Canada. In additional to the existing interventions for prevention of tick bites and Lyme disease, there is a need for new tools to help reduce the risk of Lyme disease to Canadians.

Lyme disease in athletes.

Lyme disease, a bacterial infection transmitted by ticks, is the most common vector-borne disease in the northern hemisphere. Athletes who train or compete in wooded environments in endemic regions are at increased risk of contracting Lyme disease. Variability in clinical presentation, masquerading symptoms, and limitations in testing may lead to misdiagnosis. Early diagnosis and treatment result in full recovery for most patients with Lyme disease; however symptoms may persist for months to years, especially when diagnosis is delayed. This article reviews the epidemiology, clinical manifestations, diagnosis, treatment, and prevention of Lyme disease, with focus on the athletic population.

Secondhand Tobacco Smoke Exposure Among Hospitalized Nonsmokers With Coronary Heart Disease

Secondhand Tobacco Smoke Exposure Among Hospitalized Nonsmokers With Coronary Heart Disease

Blocking pathogen transmission at the source: reservoir targeted OspA-based vaccines against Borrelia burgdorferi.

Control strategies are especially challenging for microbial diseases caused by pathogens that persist in wildlife reservoirs and use arthropod vectors to cycle amongst those species. One of the most relevant illnesses that pose a direct human health risk is Lyme disease; in the US, the Centers for Disease Control and Prevention recently revised the probable number of cases by 10-fold, to 300,000 cases per year. Caused by Borrelia burgdorferi, Lyme disease can affect the nervous system, joints and heart. No human vaccine is approved by the Food and Drug Administration. In addition to novel human vaccines, new strategies for prevention of Lyme disease consist of pest management interventions, vector-targeted vaccines and reservoir-targeted vaccines. However, even human vaccines can not prevent Lyme disease expansion into other geographical areas. The other strategies aim at reducing tick density and at disrupting the transmission of B. burgdorferi by targeting one or more key elements that maintain the enzootic cycle: the reservoir host and/or the tick vector. Here, I provide a brief overview of the application of an OspA-based wildlife reservoir targeted vaccine aimed at reducing transmission of B. burgdorferi and present it as a strategy for reducing Lyme disease risk to humans.

Tick Bite Prophylaxis: Results From a 2012 Survey of Healthcare Providers

In a recent national survey, over 30% of healthcare providers (HCPs) reported prescribing tick bite prophylaxis in the previous year. To clarify provider practices, we surveyed HCPs to determine how frequently and for what reasons they prescribed tick bite prophylaxis. We included four questions regarding tick bite prophylaxis in the DocStyles 2012 survey, a computer-administered questionnaire of 2205 US primary care physicians, paediatricians and nurse practitioners. Responses in 14 states with high Lyme disease incidence (high LDI) were compared with responses from other states (low LDI). Overall, 56.4% of 1485 providers reported prescribing tick bite prophylaxis at least once in the previous year, including 73.9% of HCPs in high LDI and 48.2% in low LDI states. The reasons given were 'to prevent Lyme disease' (76.9%), 'patients request it' (40.4%) and 'to prevent other tickborne diseases' (29.4%). Among HCPs who provided prophylaxis, 45.2% did so despite feeling that it was not indicated. Given a hypothetical scenario involving a patient with an attached tick, 38.1% of HCPs from high LDI states and 15.1% from low LDI states would prescribe a single dose of doxycycline; 19.0% from high LDI states and 27.5% from low LDI states would prescribe a full course of doxycycline. HCPs prescribe tick bite prophylaxis frequently in areas where Lyme disease is rare and for tickborne diseases for which it has not been shown effective. HCPs may be unaware of current tick bite prophylaxis guidelines or find them difficult to implement. More information is needed regarding the efficacy of tick bite prophylaxis for diseases other than Lyme disease.

Lyme disease in Canada: Focus on children

Lyme disease, the most common tick-borne infection in Canada and much of the United States, is caused by the bacteria Borrelia burgdorferi. Peak incidence for Lyme disease is among children five to nine years of age and older adults (55 to 59 years of age). The bacteria are transmitted through the bite of infected black-legged ticks of the Ixodes species. The primary hosts of black-legged ticks are mice and other rodents, small mammals, birds (which are reservoirs for B burgdorferi) and white-tailed deer. Geographical distribution of Ixodes ticks is expanding in Canada and an increasing number of cases of Lyme disease are being reported. The present practice point reviews the epidemiology, clinical presentation, diagnosis, management and prevention of Lyme disease, with a focus on children.

The cyclic-di-GMP signaling pathway in the Lyme disease spirochete, Borrelia burgdorferi.

In nature, the Lyme disease spirochete Borrelia burgdorferi cycles between the unrelated environments of the Ixodes tick vector and mammalian host. In order to survive transmission between hosts, B. burgdorferi must be able to not only detect changes in its environment, but also rapidly and appropriately respond to these changes. One manner in which this obligate parasite regulates and adapts to its changing environment is through cyclic-di-GMP (c-di-GMP) signaling. c-di-GMP has been shown to be instrumental in orchestrating the adaptation of B. burgdorferi to the tick environment. B. burgdorferi possesses only one set of c-di-GMP-metabolizing genes (one diguanylate cyclase and two distinct phosphodiesterases) and one c-di-GMP-binding PilZ-domain protein designated as PlzA. While studies in the realm of c-di-GMP signaling in B. burgdorferi have exploded in the last few years, there are still many more questions than answers. Elucidation of the importance of c-di-GMP signaling to B. burgdorferi may lead to the identification of mechanisms that are critical for the survival of B. burgdorferi in the tick phase of the enzootic cycle as well as potentially delineate a role (if any) c-di-GMP may play in the transmission and virulence of B. burgdorferi during the enzootic cycle, thereby enabling the development of effective drugs for the prevention and/or treatment of Lyme disease.

Summary of the Public Health Agency of Canada's Action Plan on Lyme Disease.

Lyme disease is an emerging infectious disease in Canada that requires a comprehensive approach to prevention and control. It is a serious illness caused by a bacterium transmitted by certain types of ticks. The risk of Lyme disease currently exists in southern parts of British Columbia and Manitoba, southern and eastern Ontario, southern Quebec and New Brunswick, and in some locations in Nova Scotia. To highlight the Public Health Agency of Canada's Action Plan on Lyme Disease, which aims to mitigate the risks to Canadians posed by Lyme disease through concrete activities being undertaken jointly with the provinces, territories, and various stakeholders. A multidisciplinary approach was used to assess the evidence on Lyme disease in Canada, analyze stakeholder concerns and evaluate what was currently available to inform public health professionals and the public. This assessment informed the development of an action plan intended to address the prevention, diagnosis and treatment of Lyme disease. The Action Plan on Lyme Disease sets out concrete action to be undertaken over three years, beginning in March 2014. It is built upon three pillars: 1.) Engagement, education and awareness, 2.) Surveillance, prevention and control, and 3.) Research and diagnosis. Effective prevention and control of Lyme disease in Canada requires a coordinated multi-partner and stakeholder engagement approach.

Lyme disease prevention and control – the way forward

Lyme disease prevention and control – the way forward

Lyme disease prevention and control - the way forward.

Lyme borreliosis is a tick-borne illness caused by the spirochete Borrelia burgdorferi, harbored primarily by small rodents, and transmitted by ticks in the genus Ixodes. It was first recognized clinically in the 1970s, in a cluster of juvenile arthritis cases in Connecticut (1). Over the last twenty five years, Lyme disease has been increasing steadily in the United States, both in case numbers and in geographic distribution. As noted in the other articles in this issue, Lyme disease has started to show a similar pattern in Canada. In the United States, there were over 30,000 cases reported to the Centers for Disease Control and Prevention (CDC) in 2012, making it the 7th most common reportable condition. The increasing numbers of cases is thought to have resulted from expanding deer populations and suburban growth that have led to abundant reservoir hosts, more ticks, and greater opportunities for exposure in humans (2). It is important to note that the observed trends for Lyme disease emergence are similar for several other tick-borne diseases that share similar ecologies, including anaplasmosis, babesiosis, ehrlichiciosis, and Powassan disease. Symptoms of Lyme disease range from an erythema migrans rash, early in the course of infection, to neuritis (e.g., facial palsy), carditis, and arthritis in later, disseminated stages of illness. Prompt treatment with 2-4 weeks of oral doxycycline results in symptomatic cure of the great majority of patients. Nevertheless, a subset of patients, especially those diagnosed and treated in later stages of illness, may have persistent fatigue, muscle aches, short-term memory problems, and other nonspecific symptoms. Consequently, one of the highest priority research needs in the field of Lyme disease is to elucidate the specific cause or causes of symptoms in these patients and to determine the safest and most effective treatment options. This question is the focus of several current or recently published research studies in humans and non-human primates that are evaluating treatment response, clinical outcome, and the possibility of spirochete persistence following treatment (3-5). Another very high priority research need is for improved diagnostics. The currently validated diagnostic tests in common use for Lyme disease are all serologic tests that rely on a detectable antibody response. Consequently, these tests have limited value early in infection or in patients who have had prior infection, depending on how long ago the infection occurred. Some of the more promising research that is ongoing in this area focuses on the identification of direct diagnostic targets. These may either be nucleic acids or low molecular weight cellular metabolites that are indicators of active infection or a specific host-mediated response to infection. One last highly critical research need worth noting is for the development and evaluation of safe and effective prevention and control tools and methods. This topic will be discussed further below. In addition to these research needs, other critical needs must be addressed in order to establish and maintain an effective public health response. These include 1.) an accurate understanding of disease distribution and risk; 2.) an awareness of the disease among the public at risk and knowledge about how to protect themselves; 3.) informed healthcare providers who can recognize the disease and provide early and accurate diagnosis and treatment; 4.) validated prevention and control practices; and 5.) effective multi-level collaboration toward the goal of prevention. The remaining sections of this paper briefly discuss each of these topics.

Reservoir Targeted Vaccine Against Borrelia burgdorferi: A New Strategy to Prevent Lyme Disease Transmission

A high prevalence of infection with Borrelia burgdorferi in ixodid ticks is correlated with a high incidence of Lyme disease. The transmission of B. burgdorferi to humans can be disrupted by targeting 2 key elements in its enzootic cycle: the reservoir host and the tick vector. In a prospective 5-year field trial, we show that oral vaccination of wild white-footed mice resulted in outer surface protein A-specific seropositivity that led to reductions of 23% and 76% in the nymphal infection prevalence in a cumulative, time-dependent manner (2 and 5 years, respectively), whereas the proportion of infected ticks recovered from control plots varied randomly over time. Significant decreases in tick infection prevalence were observed within 3 years of vaccine deployment. Implementation of such a long-term public health measure could substantially reduce the risk of human exposure to Lyme disease.

Ticks and Lyme disease: a growing threat?

Canine Lyme disease is a tick-borne condition caused by gram-negative spirochaetes belonging to the Borrelia burgdorferi group, and continues to cause concern to many members of the public, particularly those walking in high-risk areas. Both the prevalence of infection and incidence of disease in canines and humans appear to be increasing and this makes effective diagnosis, treatment and prevention measures vital to the veterinary practitioner. This article discusses the epidemiology, diagnosis, treatment and prevention of Lyme disease.

Using Risk Group Profiles as a Lightweight Qualitative Approach for Intervention Development: An Example of Prevention of Tick Bites and Lyme Disease

BackgroundMany public health campaigns use a one-size-fits-all strategy to achieve their desired effect. Public health campaigns for tick bites and Lyme disease (LD) in many countries convey all relevant preventive measures to all members of the public. Although preventing tick bites (eg, by wearing protective clothing or using repellants) and checking for tick bites after visiting a risk area are effective and cost-efficient methods to prevent an individual from contracting a tick-borne disease, public compliance to these methods is low.ObjectiveWe aimed to identify the group of individuals within the general Dutch population that are at high risk of being bitten by a tick or developing LD and to describe their characteristics, knowledge, and perceptions. The incidence of patients visiting their general practitioner for tick bites and erythema migrans (the first sign of LD) has increased tremendously in the last decades in the Netherlands and other European countries; therefore, our efforts can be used to counter this troubling trend.MethodsWe conducted in-depth semi-structured interviews to identify individuals belonging to the average risk group. Participants were recruited in two ways. Patients who visited two municipal health services travel health clinics (one in a high-endemic area and one in a low-endemic area) were asked to participate. This resulted in 18 interviews. Further, parents were recruited using the convenience sampling method, which resulted in 7 interviews. We discontinued interviewing when the point of data saturation was reached. We analyzed the results immediately after each interview to identify the point of data saturation. Data saturation is when the new interviews provided no new information compared to the previous interviews. The interviews were transcribed and analyzed using inductive thematic analysis.ResultsWe identified four groups at risk of being bitten by ticks and developing LD among the general Dutch population. The groups were as follows: (1) outdoor people that check for tick bites, (2) outdoor people that do not check for tick bites, (3) parents that check their children for tick bites, and (4) parents that do not check their children for tick bites. Previous experience with ticks or LD was the main denominator between the groups. Checking for tick bites is a more easily adopted measure than preventing tick bites. Therefore, for all groups, public health efforts in the future should primarily emphasize on the importance of checking for tick bites.ConclusionsThe lightweight qualitative approach presented in this paper is highly relevant in tailoring public health efforts toward specific groups. The profiles of members in each risk group and the motivations underlying the behaviors of the members in each risk group can be used to determine the features and content of a targeted communication strategy about ticks and LD.

Clinico-epidemiological characteristic of Lyme-borreliosis in the Ternopil’ region

The paper has generalized the clinicoepidemiological findings pertaining to the spread of systemic tickborne borreliosis in the Ternopil’ region, which is recognized to be endemic in relation to Lyme-borreliosis. The level of the disease incidence increases with every passing year. Erythema predominates among clinical forms. A serologic examination of victims for the purpose of diagnosing different clinical forms of the disease is indicated as a result of a sting by ticks. Health education is topical among the population with a view of informing about the methods of preventing Lyme disease.