B. burgdorferi sensu stricto, B. afzelii, B. garinii and B. bavariensis are the principal species which account for Lyme borreliosis (LB) globally. We have developed an internally controlled duplex quantitative real time PCR assay targeting the Borrelia 16S rRNA and the human RNAseP genes. This assay is well-suited for laboratory confirmation of suspected cases of LB and will be used to assess the efficacy of a vaccine against LB in clinical trials. The assay is highly specific, successfully detecting DNA extracted from 83 diverse B. burgdorferi sensu lato strains representing all major species causing LB, while 21 unrelated microbial species and human genomic DNA tested negative. The assay was highly reproducible and sensitive, with a lower limit of detection of 6 copies per PCR reaction. Together with culture, the assay was used to evaluate paired 3 mm skin biopsy samples taken from 121 patients presenting with solitary erythema migrans (EM) lesion. PCR testing identified more positive biopsy samples than culture (77.7% PCR positive versus 55.1% culture positive) and correctly identified all specimens scored as culture positive. OspA-based typing identified the majority of isolates as B. afzelii (96.8%) and the bacterial load was significantly higher in culture positive biopsies than in culture negative biopsies (P = .001). The quantitative data also enabled relationships between Borrelia burden and patient symptoms to be evaluated. The bacterial load was significantly higher among patients with systemic symptoms than without (P = 0.02) and was significantly higher for biopsies retrieved from patients with EM lesions with central clearing (P,0.001). 16S copy numbers were moderately lower in samples from patients reporting a history of LB (P = 0.10). This is the first quantitative PCR study of human skin biopsies predominantly infected with B. afzelii and the first study to demonstrate a clear relationship between clinical symptoms in B. afzelii-infected patients and Borrelia burden.
F.21 Development of new health/diagnostic methods/procedures
COBISS.SI-ID: 30608857A 36-year-old woman acquired severe human granulocytic anaplasmosis after blood transfusion following a cesarean section. Although intensive treatment with mechanical ventilation was needed, the patient had an excellent recovery. Disease caused by Anaplasma phagocytophilum infection was confirmed in 1 blood donor and in the transfusion recipient.
F.02 Acquisition of new scientific knowledge
COBISS.SI-ID: 30068953Lyme borreliosis, caused by spirochaetes of the Borrelia burgdorferi genospecies complex, is the most commonly reported tick-borne infection in Europe and North America. The non-specific nature of many of its clinical manifestations presents a diagnostic challenge and concise case definitions are essential for its satisfactory management. Lyme borreliosis is very similar in Europe and North America but the greater variety of genospecies in Europe leads to some important differences in clinical presentation. These new case definitions for European Lyme borreliosis emphasise recognition of clinical manifestations supported by relevant laboratory criteria and may be used in a clinical setting and also for epidemiological investigations.
F.01 Acquisition of new practical knowledge, information and skills
COBISS.SI-ID: 27269337Organisation of 12th International conference on Lyme borreliosis ond other tick-borne diseases (September 26-29, 2010, Ljubljana, Slovenia). Participants: 380 researchers: 35% from the USA, 60% from Evrope (32 from Slovenia), 5% from other parts of the world.
B.01 Organiser of a scientific meeting
18 invited lectures on Lyme borreliosis and tick-borne encephalitis were given from 2008 to 2013 at international conferences or universities outside Slovenia.
B.04 Guest lecture