Sea turtles can be considered a sentinel species for monitoring the health of marine ecosystems, acting, at the same time, as a carrier of microorganisms. Indeed, sea turtles can acquire the microbiota from their reproductive sites and feeding, contributing to the diffusion of antibiotic-resistant strains to uncontaminated environments. This study aims to unveil the presence of antibiotic-resistant bacteria in (i) loggerhead sea turtles stranded along the coast of Sicily (Mediterranean Sea), (ii) unhatched and/or hatched eggs, (iii) sand from the turtles’ nest and (iv) seawater. Forty-four bacterial strains were isolated and identified by conventional biochemical tests and 16S rDNA sequencing. The Gram-negative Aeromonas and Vibrio species were mainly found in sea turtles and seawater samples, respectively. Conversely, the Gram-positive Bacillus, Streptococcus, and Staphylococcus strains were mostly isolated from eggs and sand. The antimicrobial resistance profile of the isolates revealed that these strains were resistant to cefazolin (95.5%), streptomycin (43.2%), colistin and amoxicillin/clavulanic acid (34.1%). Moreover, metagenome analysis unveiled the presence of both antibiotic and heavy metal resistance genes, as well as the mobile element class 1 integron at an alarming percentage rate. Our results suggest that Caretta caretta could be considered a carrier of antibiotic-resistant genes.

Canine parvovirus (CPV) is the etiological agent of a severe viral disease of dogs. After its emergence in late 1970s, the CPV original type (CPV-2) was rapidly and totally replaced by three antigenic variants named CPV-2a, CPV-2b and CPV-2c. CPV has an evolutionary rate nearest to those of RNA viruses, with consequences on disease diagnosis and epidemiology. This paper reports the molecular characterization of eight CPV-2a strains collected from dogs in Italy in 2016-2017. Genetic analysis was conducted on a CPV genomic region encompassing both open reading frames (ORFs) encoding for nonstructural (NS1-NS2) and structural proteins (VP1-VP2). Sequence analysis indicates new and unreported sequence changes, mainly affecting the VP2 gene, which included the mutation Tyr324Leu. This study represents the first evidence of a new CPV-2a mutant (VP2 324Leu) and illustrates the importance of a continuous molecular survey in order to obtain more information on effective spread of new CPV mutants.

Many regions of the world are increasingly exposed to leptospirosis due to poverty, global warming and high urban density. Here, we report a molecular survey for pathogenic Leptospira spp. in rodents and two symptomatic human cases of leptospirosis in the city of Palermo, Italy. Four rodent species were captured in six areas of the city, and a molecular analysis for pathogenic Leptospira spp. on DNA from the kidney samples showed a different prevalence of leptospirosis in all the species of rodents. In addition, two human cases that occurred in May and October of 2009 in the city were also reported. A 67-year-old woman recovered after antibiotic treatment, whereas a 71-year-old woman did not survive. The weather during both of those times was notable for a violent cloudburst that caused street flooding. For the past several years, the incidence of leptospirosis has remained steady at 9 human cases every 10 years across the entire island of Sicily, with a population of almost 5 million inhabitants. The high prevalence of leptospirosis in rodents and the simultaneous presence of known risk factors, such as a mild/wet climate, street flooding and garbage accumulation, could explain the two cases of leptospirosis within the same city in the same year. This occurrence should raise awareness of this under-estimated zoonosis among public health authorities, especially given the potential fatality among elderly and immune-compromised individuals in urban settings in developed countries.

Caretta caretta is threatened by many dangers in the Mediterranean basin, but most are human-related. The purposes of this research were: (i) to investigate microflora in samples from six loggerhead sea turtle nests located on the Sicilian coast and (ii) to understand microbial diversity associated with nests, with particular attention to bacteria and fungi involved in failed hatchings. During the 2016 and 2018 summers, 456 eggs and seven dead hatchling from six nests were collected. We performed bacteriological and mycological analyses on 88 egg samples and seven dead hatchlings, allowing us to isolate: Fusarium spp. (80.6%), Aeromonas hydrophila (55.6%), Aspergillus spp. (27.2%) and Citrobacter freundii (9%). Two Fusarium species were identified by microscopy and were confirmed by PCR and internal transcribed spacer sequencing. Statistical analyses showed significant differences between nests and the presence/absence of microflora, whereas no significant differences were observed between eggs and nests. This is the first report that catalogues microflora from C. caretta nests/eggs in the Mediterranean Sea and provides key information on potential pathogens that may affect hatching success. Moreover, our results suggest the need for wider investigations over extensive areas to identify other microflora, and to better understand hatching failures and mortality related to microbial contamination in this important turtle species.

Wild environments and wildlife can be reservoirs of pathogens and antibiotic resistance. Various studies have reported the presence of zoonotic bacteria, resistant strains, and genetic elements that determine antibiotic resistance in wild animals, especially near urban centers or agricultural and zootechnical activities. The purpose of this study was the analysis, by cultural and molecular methods, of bacteria isolated from wild animals in Sicily, Italy, regarding their susceptibility profile to antibiotics and the presence of antibiotic resistance genes. Bacteriological analyses were conducted on 368 wild animals, leading to the isolation of 222 bacterial strains identified by biochemical tests and 16S rRNA sequencing. The most isolated species was Escherichia coli, followed by Clostridium perfringens and Citrobacter freundii. Antibiograms and the determination of resistance genes showed a reduced spread of bacteria carrying antibiotic resistance among wild animals in Sicily. However, since several wild animals are becoming increasingly close to residential areas, it is important to monitor their health status and to perform microbiological analyses following a One Health approach.