Entomological and ecological index for risk of infection causing lyme disease in territory of Vojvodina, Serbia

Abstract

In Europe, of all the vector transmitted diseases, the occurrence of lyme disease is the one most often registered, and the most significant vector Borrelia burgdorferi is the tick Ixodes ricinus. Both humans and animals contract lyme disease. The risk of the occurrence of lyme disease is in correlation with potential exposure to tick bites and depends on the density of the tick population in the endemic area, the percentage of ticks infected with the cause of lyme disease, the duration and the nature of the activity of the susceptible population in a certain area. The objective of these investigations was to determine the entomological and the ecological risk index, as well as to assess the risk of transmission of the cause of lyme disease in the territory of Vojvodina Province in the Republic of Serbia. Ticks were collected at 12 locations in the South Bačka District of Vojvodina. A total of 1400 ticks were identified up to the level of species. After establishing the infection of ticks with the cause of lyme disease, the entomological and the ecological index was determined for the given regions using microscopic examination in a dark field. Two species of ticks aere identified in this geographic region (Ixodes ricinus and Dermacentor marginatus). Examining I. ricinus, the prevalence of infection B. burgdorferi was established, ranging up to 33.1%. The ecological risk index indicates that there is a potential risk of humans and animals becoming infected at 8 localities. It was determined for 3 localities that there is a definite actual risk of the transferrence of causes of lyme disease.

U Evropi se, od svih vektorski prenosivih infekcija, najčešće registruje lajmska bolest, a najznačajniji vektor Borrelia burgdorferi je krpelj Ixodes ricinus. Od lajmske bolesti obolevaju ljudi i životinje. Rizik za pojavu lajmske bolesti je u korelaciji sa potencijalnim izlaganjem ubodu krpelja i zavisi od gustine populacije krpelja u endemskom području, procenta krpelja zaraženih uzročnikom lajmske bolesti, dužine i prirode aktivnosti prijemčive populacije na određenom području. Cilj ovog istraživanja je da se ustanove entomološki i ekološki indeks rizika, kao i da se proceni rizik transmisije uzročnika lajmske bolesti na području Vojvodine, Srbija. Prikupljanje krpelja je obavljeno na 12 lokacija Južnobačkog okruga, Srbija. Ukupno je do nivoa vrste identifikovano 1400 krpelja. Nakon utvrđivanja zaraženosti krpelja uzročnikom lajmske bolesti, primenom mikroskopskog pregleda u tamnom polju, izračunati su entomološki i ekološki indeks rizika za data područja. Identifikovane su dve vrste krpelja na našem geografskom području - Ixodes ricinus i Dermacentor marginatus. Kod I. ricinus utvrđena je prevalencija infekcije izazvane B. burgdorferi, koja se kretala do 33,1%. Ekološki indeks rizika ukazuje na to da potencijalni rizik od zaražavanja ljudi i životinja postoji na 8 lakaliteta. Za 3 lokaliteta je utvrđen definitivan aktuelni rizik za prenošenje uzročnika lajmske bolesti.