This study investigates the prevalence of Rickettsia spp. in Ixodes ricinus tick populations in different forest habitat types (broadleaf forest, mixed broadleaf and coniferous forest, and coniferous forest) in south-western Poland. During the survey periods from April to June 2018 and 2019 a total of 494 I. ricinus ticks, including 374 nymphs, 60 females and 60 males, were tested for Rickettsia infections by nested PCR targeting the gltA gene. The overall infection rate was 42.3%; however, we observed statistically significant year-to-year variation. Infection rates varied between tick developmental stages and were significantly influenced by forest habitat type. As assessed by a generalized linear mixed model (GLMM), the highest infection rates were observed in mixed broadleaf and coniferous forests, while coniferous forests had a significant negative effect on infection prevalence. DNA sequencing of selected samples confirmed the predominance of Rickettsia helvetica (91.2%) and less frequent Rickettsia monacensis (8.8%). This study suggests that the forest habitat types can influence Rickettsia spp. infection in tick populations; however, a comprehensive understanding of all factors influencing the level of infection requires future study.

In many European countries, cemeteries are found to be suitable habitats for the proliferation of native and invasive mosquito species. The study aimed to assess for the first time in Poland the suitability of urban cemeteries for mosquito larvae development in water supply wells. From May to September 2019 in three urban cemeteries in Wroclaw (SW Poland), a total of 757 inspection of water supply wells were carried out. The mosquito larvae development, expressed as the general container index (GCI), differed between the examined areas and months of the study. The highest GCI value was calculated for Grabiszyński and Bujwida cemeteries (72.0 % and 59.3 % respectively). Larvae of three native mosquito species were identified in all inspected breeding places during the survey: Culex pipiens s.l. Linnaeus (95 %), Cx. torrentium Martini (4 %), Anopheles maculipennis s.l. Meigen (less than 1 %). No larvae of invasive Aedes mosquito species were found. In the inspected water supply wells larval productivity peaked in June, when the average temperature reached 22.7 °C. Due to the likelihood of the establishment and adaptation of invasive aedine mosquito species in Poland, constant analysis of the larvae composition in cemeteries should be continued.

The spatial distribution of mosquito species in the course of globalization and climate warming is highly dynamic. Different studies have demonstrated the spread and establishment of thermophilic mosquito species, potentially increasing the prevalence of ‘nuisance’ mosquitoes and the local transmission of pathogens. Here we report the first recorded sampling of Anopheles hyrcanus in Wrocław, southwest Poland. This is the most northern detection of this species to date in Europe. Future spread and population development of this potential vector of malaria parasites, viruses or zoonotic helminths, such as Dirofilaria spp., must be monitored carefully. Potential factors underlying the spread of this species are discussed. Graphical Abstract

The aim of this study was to determine the level of infection of Ixodes ricinus ticks with pathogens (Borrelia spp., Rickettsia spp., and Anaplasma spp.) collected from Lacerta agilis and Zootoca vivipara lizards in the urban areas of Wrocław (SW Poland). The study was carried out in July-August 2020. Lizards were caught by a noose attached to a pole or by bare hands, identified by species, and examined for the presence of ticks. Each lizard was then released at the site of capture. Ticks were removed with tweezers, identified by species using keys, and molecular tests were performed for the presence of pathogens. From 28 lizards (17 specimens of Z. vivipara and 11 specimens of L. agilis) a total of 445 ticks, including 321 larvae and 124 nymphs, identified as I. ricinus were collected. A larger number of ticks were obtained from L. agilis compared to Z. vivipara. Molecular tests for the presence of pathogens were performed on 445 specimens of I. ricinus. The nested PCR method for the fla gene allowed the detection of Borrelia spp. in 9.4% of ticks, and it was higher in ticks from L. agilis (12.0%) than from Z. vivipara (1.0%). The RFLP method showed the presence of three species, including two belonging to the B. burgdorferi s.l. complex (B. lusitaniae and B. afzelii), and B. miyamotoi. The overall level of infection of Rickettsia spp. was 19.3%, including 27.2% in ticks collected from Z. vivipara and 17.0% from L. agilis. Sequencing of randomly selected samples confirmed the presence of R. helvetica. DNA of Anaplasma spp. was detected only in one pool of larvae collected from L. agilis, and sample sequencing confirmed the presence of (A) phagocytophilum. The research results indicate the important role of lizards as hosts of ticks and their role in maintaining pathogens in the environment including urban agglomeration as evidenced by the first recorded presence of (B) miyamotoi and (A) phagocytophilum in I. ricinus ticks collected from L. agilis. However, confirmation of the role of sand lizards in maintaining (B) miyamotoi and A. phagocytophilum requires more studies and sampling of lizard tissue.

(1) Background: Ixodes ricinus is responsible for the spreading of medically important pathogens. Monitoring the level of tick infection in various areas is essential for determining the potential tick-born risk. This study aimed to detect Borrelia spp. and Rickettsia spp. in I. ricinus ticks collected in urban and protected areas both in Poland and the Czech Republic. (2) Methods: Ticks were collected by flagging in the years 2016–2017. Borrelia spp. was detected using nested PCR targeting the flaB gene and Rickettsia spp. using nested PCR targeting gltA. (3) Results: In total, DNA of Borrelia spp. was detected in 25.9% of samples. Ticks collected in Poland were more infected compared to the Czech Republic and ticks collected in protected areas were more infected with Borrelia spp. than ticks collected in urban areas. The RFLP analysis showed the occurrence of B. afzelii and B. garinii in both countries, and additionally B. valaisiana, B. burgdorferi s.s., and B. miyamotoi in Poland. Rickettsia spp. was detected in 17.4% of I. ricinus, with comparable infection level in both countries; however, regional differences were observed. (4) Conclusion: The regional differences in Borrelia spp. and Rickettsia spp. prevalence in I. ricinus indicate the complexity of factors influencing the level of infection and underline the need for adaptation public health surveillance strategies in each region.