Ticks are obligate, bloodsucking, nonpermanent ectoparasitic arthropods. Among them, Ixodes ricinus is a classic example of an extreme generalist tick, presenting a highly permissive feeding behavior using different groups of vertebrates as hosts, such as mammalian (including humans), avian and reptilian species (Hoogstraal & Aeschlimann, 1982; Dantas-Torresa & Otranto, 2013). This ecological adaptation can account for the broad geographical distribution of I. ricinus populations, which extends from the western end of the European continent to the Ural Mountains in Russia, and from northern Norway to the Mediterranean basin, including the North African countries - Morocco, Algeria and Tunisia (https://ecdc.europa.eu/en/disease-vectors/surveillance-and-disease-data/tick-maps). The contact with different hosts also promotes the exposure/acquisition and transmission of various pathogenic agents (viruses, bacteriae, protists and nematodes) of veterinary and medical relevance (Aeschlimann et al., 1979). As one of the prime ticks found on humans, this species is implicated in diseases such as Lyme borreliosis, Spotted Fever Group rickettsiosis, Human Anaplasmosis, Human Babesiosis and Tick-borne Encephalitis (Velez et al., 2023). 

The climate change projections drawn for I. ricinus, in the scenario of global warming, point for the expansion/increase activity in both latitude and altitude (Medlock et al., 2013). The adequacy of vector modeling is relaying in the proper characterization of complex biological systems. Thus, it is essential to increase knowledge on I. ricinus, focusing on aspects such as genetic background, ecology and eco-epidemiology on a microscale but also at a country and region level, due to possible local adaptations of tick populations and genetic drift. 

In the present systematic revision, Perez et al. (2023) combine old and recently published data (mostly up to 2020) regarding I. ricinus distribution, phenology, host range and pathogen association in continental France and Corsica Island. Based on a keyword search of peer-reviewed papers on seven databases, as well as other sources of grey literature (mostly, thesis), the authors have synthesized information on: 1) Host parasitism to detect potential differences in host use comparing to other areas in Europe; 2) The spatiotemporal distribution of I. ricinus, to identify possible geographic trends in tick density, variation in activity patterns and the influence of environmental factors; 3) Tick-borne pathogens detected in this species, to better assess their spatial distribution and variation in exposure risk. 

As pointed out by both reviewers, this work clearly summarizes the information regarding I. ricinus and associated microorganisms from European France. This review also identifies remaining knowledge gaps, providing a comparable basis to orient future research. This is why I chose to recommend Perez et al (2023)'s preprint for Peer Community Infections. 

REFERENCES

Aeschlimann, A., Burgdorfer, W., Matile, H., Peter, O., Wyler, R. (1979) Aspects nouveaux du rôle de vecteur joué par Ixodes ricinus L. en Suisse. Acta Tropica, 36, 181-191.

Dantas-Torresa, F., Otranto, D. (2013) Seasonal dynamics of Ixodes ricinus on ground level and higher vegetation in a preserved wooded area in southern Europe. Veterinary Parasitology, 192, 253- 258.
https://doi.org/10.1016/j.vetpar.2012.09.034

Hoogstraal, H., Aeschlimann, A. (1982) Tick-host specificity. Mitteilungen der Schweizerischen Entomologischen Gesellschaft, 55, 5-32.

Medlock, J.M., Hansford, K.M., Bormane, A., Derdakova, M., Estrada-Peña, A., George, J.C., Golovljova, I., Jaenson, T.G.T., Jensen, J.K., Jensen, P.M., Kazimirova, M., Oteo, J.A., Papa, A., Pfister, K., Plantard, O., Randolph, S.E., Rizzoli, A., Santos-Silva, M.M., Sprong, H., Vial, L., Hendrickx, G., Zeller, H., Van Bortel, W. (2013) Driving forces for changes in geographical distribution of Ixodes ricinus ticks in Europe. Parasites and Vectors, 6. https://doi.org/10.1186/1756-3305-6-1

Perez, G., Bournez, L., Boulanger, N., Fite, J., Livoreil, B., McCoy, K., Quillery, E., René-Martellet, M., Bonnet, S. (2023) The distribution, phenology, host range and pathogen prevalence of Ixodes ricinus in France: a systematic map and narrative review. bioRxiv, ver. 1 peer-reviewed and recommended by Peer Community in Infections. https://doi.org/10.1101/2023.04.18.537315

Velez, R., De Meeûs, T., Beati, L., Younsi, H., Zhioua, E., Antunes, S., Domingos, A., Ataíde Sampaio, D., Carpinteiro, D., Moerbeck, L., Estrada-Peña, A., Santos-Silva, M.M., Santos, A.S. (2023) Development and testing of microsatellite loci for the study of population genetics of Ixodes ricinus Linnaeus, 1758 and Ixodes inopinatus Estrada-Peña, Nava & Petney, 2014 (Acari: Ixodidae) in the western Mediterranean region. Acarologia, 63, 356-372. https://doi.org/10.24349/bvem-4h49