A unique phenomenon of oral-anal contact between ticks observed in two tick species Ixodes ricinus and Dermacentor reticulatus

Occurrence of Ticks and Tick-Borne Pathogens During Warm Winter-A Snapshot from Central Europe

BACKGROUND

Climate warming and anthropogenic environmental changes impact the spread of ticks and tick-borne pathogens (TBPs). This study investigated the occurrence of ticks and the risk of TBPs infection in urban and rural recreational areas in Eastern Poland at record-high temperatures in winter.

METHODS

Ticks were collected from vegetation using the flagging method. Various types of polymerase chain reactions were applied to detect Borrelia burgdorferi s.l., Anaplasma phagocytophilum, Rickettsia spp., and Babesia spp. in the studied ticks.

RESULTS

268 ticks were sampled in the four urban/suburban and one rural sites, including 78 Ixodes ricinus specimens and 190 Dermacentor reticulatus ticks. Of the ticks, 49.19% were infected by at least one TBP, including 41.03% of I. ricinus and 63.04% of D. reticulatus specimens. Co-infections with TBPs that involved only I. ricinus were recorded in 6.41% of these ticks.

CONCLUSIONS

The study indicates that hosts are exposed to tick attacks and TBPs infection in Central Europe at high temperatures in winter. The high activity of ticks may increase the incidence of tick-borne diseases in humans and companion animals. The record's importance indicates that practical preventive measures against TBPs should be taken due to weather conditions rather than the season.

Rickettsia Species: Genetic Variability, Vectors, and Rickettsiosis-A Review

Rickettsiae are an interesting group of bacteria comprising a large number of obligate intracellular species. The circulation of these bacteria in the environment depends on the presence of vectors (blood-sucking invertebrates) and their hosts. On the basis of phylogenetic analyses in 2022, a division into five groups of Rickettsia has been proposed: I belli group, II canadensis group, III typhus group, and IV and V spotted group fever (respectively II, phylogenetically older, and I). The genus Rickettsia includes species that are both pathogenic and nonpathogenic to humans and domestic and wild animals. Some Rickettsia species are invertebrate symbionts. Currently, rickettsiae, which are transmitted mainly by ticks, are spreading worldwide. This has been promoted by climate change, environmental changes caused by humans, and the synanthropisation of plants and animals. Therefore, it is extremely important to monitor the natural and urban environments. The study of potential vectors and reservoirs of bacteria in the genus Rickettsia should be a permanent part of the analysis of the modern human environment.

The Potential Role of Migratory Birds in the Rapid Spread of Ticks and Tick-Borne Pathogens in the Changing Climatic and Environmental Conditions in Europe

This opinion piece highlights the role of migratory birds in the spread of ticks and their role in the circulation and dissemination of pathogens in Europe. Birds with different lifestyles, i.e., non-migrants residing in a specific area, or short-, medium-, and long-distance migrants, migrating within one or several distant geographical regions are carriers of a number of ticks and tick-borne pathogens. During seasonal migrations, birds that cover long distances over a short time and stay temporarily in different habitats can introduce tick and pathogen species in areas where they have never occurred. An increase in the geographical range of ticks as well as the global climate changes affecting the pathogens, vectors, and their hosts increase the incidence and the spread of emerging tick-borne diseases worldwide. Tick infestations of birds varied between regions depends on the rhythms of tick seasonal activity and the bird migration rhythms determined by for example, climatic and environmental factors. In areas north of latitude ca. 58°N, immature Ixodes ricinus ticks are collected from birds most frequently, whereas ticks from the Hyalomma marginatum group dominate in areas below 42°N. We concluded that the prognosis of hazards posed by tick-borne pathogens should take into account changes in the migration of birds, hosts of many epidemiologically important tick species.