Influence of ecological and climatic conditions on the spread of Borrelia burgdorferi in domestic dogs in Ukraine

Lyme-borreliosis is a zoonotic, infectious disease that has a complex chain of transmission of the pathogen Borrelia burgdorferi sensu lato and includes the relationship between ixodid ticks, vertebrate hosts, humans and companion animals in the environment. The article shows general trends in the prevalence of canine Lyme-borreliosis in Ukraine depending on environmental, climatic and physiographic factors. The results of a comparative cartographic analysis of the prevalence of Lyme borreliosis among domestic dogs in Ukraine are presented by systematizing, mathematical and statistical processing of the data obtained by surveying veterinarians engaged in clinical veterinary practice. The paper includes generalized data on the clinical manifestations, methods of diagnosis and treatment of Lyme borreliosis in dogs. We determined the dependence of the prevalence of Lyme borreliosis in dogs on the types of physical and geographical territories – natural zones of Ukraine. Each of the natural zones differs in types of relief, climatic conditions, soil types, composition of fauna and flora, which affect the epizootic chain of Lyme disease. There is a clear correlation between the incidence of Lyme borreliosis in dogs and the types of natural areas. The highest incidence of Lyme borreliosis in dogs was observed in the forest-steppe zone and the zone of broad-leaved forests. A sharp decrease in the incidence of dogs was recorded in areas of mixed forests, the Ukrainian Carpathians and in the South of Ukraine in the steppe zone. The study also confirmed that the prevalence of Lyme disease among domestic dogs was influenced by the climatic factors, in particular: gross moisture of territories, average annual air temperature and soil temperature. In Ukraine, veterinarians in the vast majority of cases use serological diagnostic methods: immunochromatographic analysis, immunoenzymatic assay, and western blot, which are insufficient, since the presence of antibodies to the Lyme borreliosis pathogen is only a confirmation of the animal's contact with the antigen and may not indicate the presence of the disease in the clinical form. The generalized data on the use of antimicrobial drugs in the treatment of Lyme borreliosis in dogs indicate the predominant use of tetracycline antibiotics and cephalosporins. The majority of veterinarians reported symptoms of Lyme arthritis, somewhat fewer reported Lyme nephritis, neuroborreliosis, Lyme carditis and in rare cases, veterinarians observed erythema at the site of tick bite. About half of the veterinarians in Ukraine observed an increase in the incidence of Lyme disease in dogs, indicating a probable deterioration of the epizootic and epidemiological situation regarding Lyme borreliosis, especially in areas with favourable conditions for the circulation of Lyme borreliosis pathogens in natural and urban ecotopes. The results substantiate the need for the further study of the circulation of Borrelia burgdorferi sensu lato and their ability to cause disease in humans and animals, as well as the need to implement the principles of the One Health concept for the control and management of Lyme borreliosis.

Oral Doxycycline Compared to Intravenous Ceftriaxone in the Treatment of Lyme Neuroborreliosis: A Multicenter, Equivalence, Randomized, Open-label Trial

BACKGROUND

Lyme neuroborreliosis (LNB) is often treated with intravenous ceftriaxone even if doxycycline is suggested to be noninferior to ceftriaxone. We evaluated the efficacy of oral doxycycline in comparison to ceftriaxone in the treatment of LNB.

METHODS

Patients with neurological symptoms suggestive of LNB without other obvious reasons were recruited. The inclusion criteria were (1) production of Borrelia burgdorferi-specific antibodies in cerebrospinal fluid (CSF) or serum; (2) B. burgdorferi DNA in the CSF; or (3) an erythema migrans during the past 3 months. Participants were randomized in a 1:1 ratio to receive either oral doxycycline 100 mg twice daily for 4 weeks, or intravenous ceftriaxone 2 g daily for 3 weeks. The participants described their subjective condition with a visual analogue scale (VAS) from 0 to 10 (0 = normal; 10 = worst) before the treatment, and 4 and 12 months after the treatment. The primary outcome was the change in the VAS score at 12 months.

RESULTS

Between 14 September 2012 and 28 December 2017, 210 adults with suspected LNB were assigned to receive doxycycline (n = 104) or ceftriaxone (n = 106). The per-protocol analysis comprised 82 patients with doxycycline and 84 patients with ceftriaxone. The mean change in the VAS score was -3.9 in the doxycycline group and -3.8 in the ceftriaxone group (mean difference, 0.17 [95% confidence interval, -.59 to .92], which is within the prespecified equivalence margins of -1 to 1 units). Participants in both groups improved equally.

CONCLUSIONS

Oral doxycycline is equally effective as intravenous ceftriaxone in the treatment of LNB.

CLINICAL TRIALS REGISTRATION

NCT01635530 and EudraCT 2012-000313-37.

ACVIM consensus update on Lyme borreliosis in dogs and cats

An update of the 2006 American College of Veterinary Internal Medicine (ACVIM) Small Animal Consensus Statement on Lyme Disease in Dogs: Diagnosis, Treatment, and Prevention was presented at the 2016 ACVIM Forum in Denver, CO, followed by panel and audience discussion and a drafted consensus statement distributed online to diplomates for comment. The updated consensus statement is presented below. The consensus statement aims to provide guidance on the diagnosis, treatment, and prevention of Lyme borreliosis in dogs and cats.

[Lyme borreliosis]

Lyme borreliosis is a multisystem infectious disease affecting mainly the skin, nervous system, joints and heart. It is caused by spirochetes of the Borrelia burgdorferi sensu lato complex which are transmitted by ticks. The diagnosis of Lyme borreliosis is based primarily on typical clinical symptoms and signs with serological confirmation. Antibiotic therapy is beneficial for all manifestations and treatment refractory cases are rare. The diagnosis "chronic Lyme borreliosis" is increasingly being misused for all conceivable medically unexplained symptoms.

Culture of the entire mouse to determine whether cultivable Borrelia burgdorferi persists in infected mice treated with a five-day course of Ceftriaxone

Although controversial, it has been suggested that antibiotic treatment of laboratory animals infected with Borrelia burgdorferi often leads to the persistence of residual spirochetes that are claimed to be viable but noncultivable. If viable cells of B. burgdorferi do persist following antibiotic therapy, one possible explanation for the lack of cultivability is that too few organisms persist in any given tissue site that might be sampled and cultured. In this study, we treated SKH (hairless) mice, with B. burgdorferi infection of 3 months' duration, with either ceftriaxone or saline for 5 days and then cultured a suspension extract of nearly the entire mouse using a combined in vivo/in vitro culture method. All of the saline-treated (control) mice were culture positive, compared with none of the antibiotic-treated mice. Our findings further document the effectiveness of antibiotic therapy in eradicating cultivable cells of B. burgdorferi, irrespective of tissue or organ site.

Lyme borreliosis in southern United Kingdom and a case for a new syndrome, chronic arthropod-borne neuropathy

This series of serologically confirmed Lyme disease is the largest reported in the UK and represents 508 patients who presented to one hospital in the South of England between 1992 and 2012. The mean rate of borreliosis throughout this period was 9·8/100,000 population, much higher than the reported national rate of 1·7/100,000. The actual rate increased each year until 2009 when it levelled off. Patients clinically presented with rash (71%), neurological symptoms (16%, of whom half had VII cranial nerve palsies), arthropathy (8%), pyrexia (5%), cardiac abnormalities (1%) or other manifestations (<1%). Twenty percent of patients had additional non-specific symptoms of fatigue, myalgia, and cognitive changes. Serological diagnosis was with a two-tiered system of ELISA and immunoblot. There was a marked seasonal presentation in the summer months and in the first and sixth decades of life. A third of patients gave a clear history of a tick bite. The median interval between tick bite and clinical symptoms was 15 days [interquartile range (IQR) 9-28 days], with a further interval of 14 days to clinical diagnosis/treatment (IQR 2-31 days). Most cases were acquired locally and only 5% abroad. Patients responded to standard antibiotic therapy and recurrence or persistence was extremely rare. A second group of patients, not included in the clinical case series, were those who believed they had Lyme disease based on a probable tick bite but were seronegative by currently available validated tests and presented with subjective symptoms. This condition is often labelled chronic Lyme disease. These patients have a different disease from Lyme disease and therefore an alternative name, chronic arthropod-borne neuropathy (CAN), and case definition for this condition is proposed. We suggest that this chronic condition needs to be distinguished from Lyme disease, as calling the chronic illness 'Lyme disease' causes confusion to patients and physicians. We recommend research initiatives to investigate the aetiology, diagnosis and therapy of CAN.

Xenodiagnosis to detect Borrelia burgdorferi infection: a first-in-human study

BACKGROUND

Animal studies suggest that Borrelia burgdorferi, the agent of Lyme disease, may persist after antibiotic therapy and can be detected by various means including xenodiagnosis using the natural tick vector (Ixodes scapularis). No convincing evidence exists for the persistence of viable spirochetes after recommended courses of antibiotic therapy in humans. We determined the safety of using I. scapularis larvae for the xenodiagnosis of B. burgdorferi infection in humans.

METHODS

Laboratory-reared larval I. scapularis ticks were placed on 36 subjects and allowed to feed to repletion. Ticks were tested for B. burgdorferi by polymerase chain reaction (PCR), culture, and/or isothermal amplification followed by PCR and electrospray ionization mass spectroscopy. In addition, attempts were made to infect immunodeficient mice by tick bite or inoculation of tick contents. Xenodiagnosis was repeated in 7 individuals.

RESULTS

Xenodiagnosis was well tolerated with no severe adverse events. The most common adverse event was mild itching at the tick attachment site. Xenodiagnosis was negative in 16 patients with posttreatment Lyme disease syndrome (PTLDS) and/or high C6 antibody levels and in 5 patients after completing antibiotic therapy for erythema migrans. Xenodiagnosis was positive for B. burgdorferi DNA in a patient with erythema migrans early during therapy and in a patient with PTLDS. There is insufficient evidence, however, to conclude that viable spirochetes were present in either patient.

CONCLUSIONS

Xenodiagnosis using Ixodes scapularis larvae was safe and well tolerated. Further studies are needed to determine the sensitivity of xenodiagnosis in patients with Lyme disease and the significance of a positive result. Clinical Trials Registration NCT01143558.

Treatment of erythema migrans with doxycycline for 10 days versus 15 days

BACKGROUND

The efficacy of 10-day doxycycline treatment in patients with erythema migrans has been assessed in the United States but not in Europe. Experts disagree on the significance of post-Lyme borreliosis symptoms.

METHODS

In a noninferiority trial, the efficacies of 10 days and 15 days of oral doxycycline therapy were evaluated in adult European patients with erythema migrans. The prevalence of nonspecific symptoms was compared between patients with erythema migrans and 81 control subjects without a history of Lyme borreliosis. The efficacy of treatment, determined on the basis of clinical observations and microbiologic tests, was assessed at 14 days and at 2, 6, and 12 months. Nonspecific symptoms in patients and controls were compared at 6 months after enrollment.

RESULTS

A total of 117 patients (52%) were treated with doxycycline for 15 days, and 108 (48%) received doxycycline for 10 days. Twelve months after enrollment, 85 of 91 patients (93.4%) in the 15-day group and 79 of 86 (91.9%) in the 10-day group had complete response (difference, 1.6 percentage points; upper limit of the 95% confidence interval, 9.1 percentage points). At 6 months, the frequency of nonspecific symptoms in the patients was similar to that among controls.

CONCLUSIONS

The 10-day regimen of oral doxycycline was not inferior to the 15-day regimen among adult European patients with solitary erythema migrans. Six months after treatment, the frequency of nonspecific symptoms among erythema migrans patients was similar to that among control subjects.

CLINICAL TRIALS REGISTRATION

NCT00910715.

The pain of "chronic Lyme disease": moving the discourse in a different direction

About 30% of the population of the United States suffers from acute or chronic pain, often of unknown cause. Among this group might be included patients with symptoms claimed to be caused by a poorly defined condition called "chronic Lyme disease" in which chronic pain is a major contributor. Since there is no evidence to indicate that chronic Lyme disease is due to a persistent infection and that extended antibiotic therapy is beneficial and safe, this condition should not be viewed solely as an infectious disease problem. Rather, it should be considered within the context of a broad-based, multidisciplinary approach to determining the cause of chronic pain per se and developing more effective strategies for its treatment as outlined in a recent report on pain issued by the Institute of Medicine.

Antiscience and ethical concerns associated with advocacy of Lyme disease

Advocacy for Lyme disease has become an increasingly important part of an antiscience movement that denies both the viral cause of AIDS and the benefits of vaccines and that supports unproven (sometimes dangerous) alternative medical treatments. Some activists portray Lyme disease, a geographically limited tick-borne infection, as a disease that is insidious, ubiquitous, difficult to diagnose, and almost incurable; they also propose that the disease causes mainly non-specific symptoms that can be treated only with long-term antibiotics and other unorthodox and unvalidated treatments. Similar to other antiscience groups, these advocates have created a pseudoscientific and alternative selection of practitioners, research, and publications and have coordinated public protests, accused opponents of both corruption and conspiracy, and spurred legislative efforts to subvert evidence-based medicine and peer-reviewed science. The relations and actions of some activists, medical practitioners, and commercial bodies involved in Lyme disease advocacy pose a threat to public health.

Following a tick bite: double infections by tick-borne encephalitis virus and the spirochete Borrelia and other potential multiple infections

In Central Europe and large parts of Asia, tick-borne-encephalitis (TBE) and Lyme borreliosis caused by the spirochetal bacterium of the genus Borrelia are among the most common diseases transmitted by the bite of a tick. When in regions with overlapping TBE virus and Borrelia endemicity, a tick bite causes the victim to become ill, it is important that appropriate serological and other laboratory investigations form part of the differential diagnosis. Account must always be taken of the fact that a tick bite may be followed by a double infection with the TBE virus and Borrelia. For this reason, a comprehensive diagnostic work-up aimed at detecting co-infection by both pathogens, even when the tick bite occurs in an endemic region for both pathogens but the initial clinical symptoms suggest an infection with only one of the two pathogens. The present article discusses a number of published cases of a co-infection with TBE virus and Borrelia and other potential multiple infections.

Identification of membrane associated drug targets in Borrelia burgdorferi ZS7- subtractive genomics approach

Lyme disease is an infectious disease caused by a spirochete Borrelia burgdorferi ZS7. This spirochete is most often spread by ticks. Single antibiotic therapy is sufficient for containment of the early stage progression of the disease but combinational therapy is more preferred in later stages. Research is in progress for the development of drugs against the pathogen, but till date no vaccines have been developed to effect the late stage infections. There is a rapid rise in the cases of antibiotic-resistant population which is more than 10% of the total infected individuals. In such condition vaccine becomes the sole alternative for prevention. Therefore effective treatment includes antibiotic combination and combination of antigenic surfaces (for vaccine preparation). Thus, a comprehensive list of drug targets unique to the microorganisms is often necessary. Availability of Borrelia burgdorferi ZS7 proteome has enabled insilico analysis of protein sequences for the identification of drug targets and vaccine targets. In this study, 272 essential proteins were identified out of which 42 proteins were unique to the microorganism. The study identified 15 membrane localized drug targets. Amongst these 15, molecular modeling and structure validation of the five membrane localized drug target proteins could only be achieved because of the low sequence identity of the remaining proteins with RCSB structures. These 3D structures can be further characterized by invitro and invivo studies for the development of novel vaccine epitopes and novel antibiotic therapy against Borrelia burgdorferi.