Frequency of lyme disease in patients with tick contact and identification of ticks from Bolu province of Turkey.

BACKGROUND OBJECTIVES: Lyme disease is a multisystemic disease caused by the bacteria in the Borrelia burgdorferi sensu lato complex, which is transmitted by ticks of Ixodes genus. Although there are seroprevalence studies and case reports of Lyme disease from various regions in Turkey, there is no widespread epidemiological research. This study aimed to determine the frequency of Lyme disease in the cases followed-up after tick contact and to examine the isolated ticks to reveal tick population from Bolu province.

METHODS: The cases who applied to the emergency department due to tick contact between April and September 2020 were firstly evaluated in our infectious diseases and clinical microbiology outpatient clinic on the third day of exposure and antibodies against Lyme disease were investigated with IFA method to exclude the patients who were previously exposed to B. burgdrorferi. Thereafter, patients were requested to continue outpatient visits at the 1st and 3rd month control. At these controls serum samples were taken to study B. burgdorferi antibodies with ELISA method which was stored at -20°C until the study day.

RESULTS: Out of 123 patients who came to first control, 69 patients continued later to at least one of the two controls (either at first or third month). Of these 69 patients, only one (1.4%) was diagnosed with Lyme borreliosis according to clinical and laboratory features. Erythema migrans did not occur in any of the cases. Serum samples were assessed by ELISA method. Asymptomatic infection was detected in 22 cases (30.5%). In addition, we could obtain 46 ticks from our cases and two genera were identified. Forty-two (91.3%) were Ixodes spp, and two (4.3%) were Hyalomma spp.

INTERPRETATION CONCLUSION: In this study, which was carried out for the first time in the province of Bolu, it was concluded that the cases presenting with a history of tick contact were most frequently exposed to Ixodes spp ticks and the probability of developing Lyme borreliosis was low (1.4%) during the three-month follow-up. Further studies with a greater number of cases and more extended follow-up period are needed.