For birds and humans: challenges and benefits of rat eradication from an inhabited island (Ventotene, central Italy).

BACKGROUND: Rat eradication from islands is a very effective tool that can free entire ecosystems from the pressure of alien predators. In this study we present the case study of Ventotene (Ponziane Archipelago, central Italy), which to date is the island with by far the greatest number of human inhabitants ever freed from the negative implications of rats. Rat eradication was carried out in the framework of the Life PonDerat project, co-financed by the European Union. Besides considering the conservation benefits due to the removal of rats, we also considered the socio-economic and pathogenic impacts from introduced rats. RESULTS: The overall economic cost of the rats was quantified to be at least €18 500 per year to the residents of the island. Several zoonotic pathogens were detected in the rat population prior to eradication. A reduction in the rodenticide distributed over time on the island was also estimated. Identifying the origin of the rat population allowed for the development of more targeted and effective biosecurity measures. The eradication effort was challenged by the presence of domestic animals and variability in support for baiting in urbanised areas. CONCLUSIONS: The results of this study open up new perspectives on island restoration projects. We demonstrated the cost-effectiveness of the action, including ecosystem restoration, reduction of rat impacts in agricultural systems, and improving overall health and food safety. Our findings will have implications for similar interventions on other islands, potentially bringing significant benefits. © 2023 Society of Chemical Industry.

A new fast real-time PCR method for the identification of three sibling Apodemus species (A. sylvaticus, A. flavicollis, and A. alpicola) in Italy.

The identification of field mice Apodemus flavicollis, Apodemus sylvaticus, and Apodemus alpicola represents a challenge for field scientists due to their highly overlapping morphological traits and habitats. Here, we propose a new fast real-time PCR method to discriminate the three species by species-specific TaqMan assays. Primers and probes were designed based on the alignment of 54 cyt-b partial sequences from 25 different European countries retrieved from GenBank. TaqMan assays were then tested on 133 samples from three different areas of Italy. Real-time PCR analysis showed 92 samples classified as A. flavicollis, 13 as A. sylvaticus, and 28 as A. alpicola. We did not observe any double amplification and DNA sequencing confirmed species assignment obtained by the TaqMan assays. The method is implementable on different matrices (ear tissues, tail, and blood). It can be used on dead specimens or on alive animals with minimally invasive sampling, and given the high sensitivity, the assay may be also suitable for degraded or low-DNA samples. The method proved to work well to discriminate between the species analyzed. Furthermore, it gives clear results (amplified or not) and it does not require any postamplification handling of PCR product, reducing the time needed for the analyses and the risk of carryover contamination. It therefore represents a valuable tool for field ecologists, conservationists, and epidemiologists.

Serological Survey of Hantavirus and Flavivirus Among Wild Rodents in Central Italy.

Hantaviruses are a group of zoonotic viruses carried by rodents. Puumala virus (PUUV) and Dobrava virus (DOBV) are the causative agents of human hantavirus infections in Europe. Knowledge about hantavirus circulation in Italy is very scarce. West Nile virus (WNV) and Usutu virus (USUV) are emerging neuropathogenic flaviviruses, both endemic in most part of the Italian territories. To monitor the circulation of PUUV, DOBV, WNV, and USUV in natural environment in central Italy, we carried out serological surveillance in wild rodents. During this study, 90 animals were captured in forested areas of Abruzzo and Marche regions and tested with serological assays for the specific pathogens. Serological test provided no evidence of PUUV and DOBV circulation in the studied area. However, four rodents (Apodemus flavicollis) were found to be positive by WNV ELISA test. Two of them were confirmed as WNV by virus neutralization test.

Detection of Lyme Disease and Q Fever Agents in Wild Rodents in Central Italy.

The maintenance of tick-borne disease agents in the environment strictly depends on the relationship between tick vectors and their hosts, which act as reservoirs for these pathogens. A pilot study aimed to investigate wild rodents as reservoirs for zoonotic tick-borne pathogens (Borrelia burgdorferi sensu lato (s.l.), Coxiella burnetii, Francisella tularensis, and Anaplasma phagocytophilum) was carried out in an area of Gran Sasso e Monti della Laga National Park (Abruzzi Region, central Italy), a wide protected area where, despite sporadic reports of infection in humans and animals, eco-epidemiological data on these diseases are still not available. Rodents were trapped and released at the capture site after the collection of feeding ticks and blood samples. In all, 172 ticks were collected; the most frequent species was Ixodes acuminatus (53%). Out of 88 tick pools, 11 resulted positive for C. burnetii and 13 for B. burgdorferi s.l.; the Borrelia afzelii genospecies was identified in one Ixodes ricinus tick collected from one Apodemus sp. rodent. Out of 143 blood samples, seven Apodemus spp. and five Myodes glareolus were positive for B. burgdorferi s.l. and two Apodemus spp. were positive for C. burnetii. All samples (ticks and blood) were negative for F. tularensis and A. phagocytophilum. This is the first report of B. burgdorferi s.l. in the environment for Abruzzi Region. Data on the presence of B. burgdorferi s.l. are similar to that observed in other Mediterranean countries. The present work is also the first report of C. burnetii in wild rodents in Italy. C. burnetii infection has been largely investigated in Italy in ruminant farms by serology and molecular methods, but information on ecology and on the wild cycle are still lacking. Further studies including genotyping should be performed and species-specific differences between wild rodent reservoirs of Q fever and Lyme disease agents should be investigated.