Tick-borne pathogen diversity and clinical impact of tick-infestation in Serbia and North Macedonia
Dejan Jakimovski, Pavle Banović, Sofija Mateska, Marija Stavrova, Angela Stamenkovska, Mile Bosilkovski, Dragana Mijatović, Ivana Bogdan, Verica Simin, Kinga Lis, Adrian A. Diaz-Sanchez, Dasiel Obregon, Sara Moutailler, Angélique Foucault-Simonin, Zbigniew Zając, Natasha Griffith, Alejandro Cabezas-Cruz
A new cross-border study from Serbia and North Macedonia has found that ticks biting humans in the Balkans frequently carry disease-causing microorganisms, raising concerns about the region’s growing role as a hotspot for tick-borne infections.
Researchers examined 135 ticks removed from 133 patients and found that two-thirds carried DNA from at least one tick-borne pathogen. The most common were Rickettsia helvetica and Rickettsia monacensis, bacteria linked to spotted fever group rickettsioses. Some ticks carried multiple pathogens at the same time, including Borrelia, Anaplasma, and Babesia species.
Despite the high pathogen burden in ticks, serious illness among patients was rare. A small number had pathogen DNA detected in their blood but remained asymptomatic during follow-up. The most common clinical outcome was a local skin reaction at the bite site, suggesting that many post-tick bite symptoms may be allergic or inflammatory responses rather than true infections.
The study also identified two cases of α-Gal sensitization, an immune response associated with tick exposure and, in some cases, red meat allergy. Genetic analysis showed that most detected pathogen strains resembled those circulating elsewhere in Europe, although one Borrelia garinii strain from North Macedonia clustered with strains from Russia and China, suggesting possible long-distance introduction.
The authors say the findings highlight the need for stronger tick surveillance across the Balkans, particularly as climate and ecological changes reshape tick habitats. They also caution clinicians not to rush to antibiotic treatment for every local skin reaction after a tick bite, recommending continued clinical monitoring as the key management approach.
More information here.