The contribution of citizen science in the surveillance of wildlife and related arthropods.

Environmental and anthropogenic factors may significantly affect the diffusion of wild animals, enhancing the interface of human­wildlife interactions and driving the spread of pathogens and vector-borne diseases between animals and humans. However, in the last decade, the involvement of citizens in scientific research (the so-called citizen science approach, henceforth abbreviated as CS) provided a network of large-scale and cost-effective surveillance programmes of wildlife populations and their related arthropod species. Therefore, this review aims to illustrate different methods and tools used in CS studies, by arguing the main advantages and considering the limitations of this approach. The CS approach has proven to be an effective method for establishing density and distribution of several wild animal species, in urban, peri-urban and rural environments, as well a source of information regarding vector­host associations between arthropods and wildlife. Extensive efforts are recommended to motivate citizens to be involved in scientific projects to improve both their and our knowledge of the ecology and diseases of wildlife. Following the One Health paradigm, collaborative and multidisciplinary models for the surveillance of wildlife and related arthropod species should be further developed by harnessing the potentiality of the CS approach.

First description of Eucoleus garfiai (Gallego and Mas-Coma, 1975) in wild boar (Sus scrofa) in Italy.

Eucoleus garfiai (syn. Capillaria garfiai) is a nematode infecting lingual tissue of domestic and wild swine. Prevalence data for this parasite are scant and often related to accidental findings, occurring only in Japan and a few European countries. In this study, an epidemiological survey was performed in order to identify E. garfiai in wild boar from the Campania region, southern Italy. A total of 153 wild boar carcasses were inspected over the course of two hunting seasons (2019-2020). Histological examinations were performed on tongue samples fixed and stained with haematoxylin and eosin. The scraping of dorsal tongue tissue was carried out to collect adult worms for parasitological examination. Out of 153 wild boars, 40 (26.1%, 95% CI: 19.8-33.6%) tested positive for helminths and/or eggs in tongue tissues. Parasites were identified morphologically and identification was confirmed by molecular analysis of the 18S rRNA gene, showing a 99% nucleotide match with E. garfiai sequences available in literature. No statistically significant differences were found according to age, sex nor hunting province. Our findings agree with previous histopathological data confirming the low pathogenic impact of this nematode. The present study represents the first report of E. garfiai in wild boar from Italy.

Taenia hydatigena cysticercosis in wild boar (Sus scrofa) from southern Italy: an epidemiological and molecular survey.

Taenia hydatigena cysticercosis is a widespread parasitic disease of wild and domestic animals. In Europe, the increase in wild boar population may potentially contribute to the spread of this parasitic infection. To determine the occurrence of cysticerci (metacestodes) in wild boar population from southern Italy, carcasses were inspected during three hunting seasons (2016-2018). Out of 3363 wild boar examined, 229 (6.8%) harboured cysticerci with 188 (82.1%) infected by a single cyst, vs 41 (17.9%) boars having more than one. Most of the positive animals (187; 81.7%) showed cysts on the liver, whereas a multiple localization of cysticerci was reported in 10 (4.4%) wild boar. The total number of cysts retrieved from positive animals was 301 (average 1.3). Molecular analysis revealed the occurrence of a common haplotype (Hap 8) shared between wild boar and domestic animals. Our findings suggest the presence of a T. hydatigena semi-domestic life cycle in which wild boar may play an important role, due to a large number of offal available to hunting dogs, wolves and foxes during hunting seasons. Hunters may be players in the management of wildlife species to control and prevent the circulation of parasitic diseases.

First detection of zoonotic tapeworm Echinococcus granulosus sensu lato genotype G7 in continental Italy.

The larval stage of the species complex Echinococcus granulosus sensu lato (s.l.) is the cause of a widespread zoonotic disease known as cystic echinococcosis (CE). The disease is highly prevalent in southern Italy and represents a serious public health issue. The main aim of this study was to characterize E. granulosus s.l. genotypes from wild boar on a continental area of Italy (Campania region), using recently developed mtDNA markers of nad2 and nad5 for reliable identification of different genotypes. Here, nad5 (680 bp) allowed for a clear identification of G1 and G3, whereas a combination of nad2 (714 bp) and nad5 (1394 bp in total) did the same for genotype G7 and its haplogroups G7a and G7b. The results of this study revealed for the first time the presence of genotype G7 in continental Italy. While haplogroup G7b was previously shown to be restricted to the islands of Corsica and Sardinia, here we demonstrate that haplogroup G7b is also present on the mainland of Italy. This work has implications in designing future strategies to reduce CE in Italy.

First identification of porcine parvovirus 3 in a wild boar in Italy by viral metagenomics - Short communication.

Metagenomic analysis revealed the presence of porcine parvovirus 3 (PPV3) in the pool of the internal organs of a wild boar found dead in Southern Italy. Phylogenetic analysis based on the complete coding sequences showed that the newly detected virus is most closely related to those found also in wild boars in Romania during 2010-2011. Even though the death could not be associated with this virus, PPV3 could have contributed to lowering the host's immunological defences.

Seroprevalence and risk factors associated with Ehrlichia canis, Anaplasma spp., Borrelia burgdorferi sensu lato, and D. immitis in hunting dogs from southern Italy.

Canine vector-borne diseases (CVBDs) are caused by a range of pathogens transmitted to dogs by arthropods. The present study investigates Ehrlichia canis, Anaplasma spp., Borrelia burgdorferi sensu lato, and Dirofilaria immitis seroprevalences in hunting dogs from southern Italy. Dogs (no. 1335) were tested using a commercial in-clinic enzyme-linked immunosorbent assay kit. Odds ratios (ORs) were calculated by logistic regression analysis to identify risk factors. Overall, 138/1335 dogs (10.3%) were seroreactive to at least one CVBD pathogen. E. canis, Anaplasma spp., B. burgdorferi s.l., and D. immitis seroprevalences were 7.6, 4.4, 0.3, and 0.2%, respectively. E. canis and Anaplasma spp. co-exposures were found in 30 dogs (2.2%), compared with Anaplasma spp. and B. burgdorferi s.l. co-exposures in 2 dogs (0.1%). Adult age was a risk factor for E. canis (OR 2.35) seroreactivity whereas hunting fur-bearing animals for E. canis (OR 4.75) and Anaplasma spp. (OR 1.87), respectively. The historical presence of tick infestation was identified as a risk factor for positivity to E. canis (OR 2.08) and Anaplasma spp. (OR 2.15). Finally, larger dog pack size was significantly associated with E. canis (OR 1.85) and Anaplasma spp. (OR 2.42) exposures. The results of the present survey indicated that hunting dog populations are at relative risk of CVBDs in southern Italy. Further studies are needed to evaluate the role of hunting dogs in the epidemiology of vector-borne organisms due to sharing common environments with wild, sympatric animal populations.

Molecular survey of Ehrlichia canis and Coxiella burnetii infections in wild mammals of southern Italy.

Ehrlichiosis and Q fever caused by the intracellular bacteria Ehrlichia canis and Coxiella burnetii, respectively, are tick-borne diseases with zoonotic potential and widespread geographical distribution. This study investigated the prevalence of both infections in wild mammals in southern Italy. Tissue samples obtained from the red fox (Vulpes vulpes), European badger (Meles meles), gray wolf (Canis lupus), beech marten (Martes foina), and crested porcupine (Hystrix cristata) were processed for molecular detection of both pathogens. E. canis was detected in 55 out of 105 (52 %) red foxes and three out of six gray wolves. Four sequence types were identified, three of which were found in the spleen and liver samples of red foxes and wolves, and one in the kidney of a red fox. None of the examined mammals was positive to C. burnetii type. This represents the first report of E. canis in free-ranging wolves worldwide, as well as the first evidence of this pathogen in red foxes in the peninsular Italy. Our results suggest that E. canis infection is common in free-ranging canids in southern Italy and that a sylvatic life cycle of this pathogen may occur.

Crenosoma vulpis in wild and domestic carnivores from Italy: a morphological and molecular study.

Crenosoma vulpis is a metastrongyloid nematode primarily associated with respiratory tract infections of red foxes in North America and Europe. Sporadic cases have also been reported in domestic dogs. The present study aimed to provide morphological, molecular, and epidemiological data on the geographical distribution of this nematode throughout Italy. From 2012 to 2014, 12 of the 138 foxes examined, three dogs and one badger scored positive for C. vulpis. Forty adults were isolated from foxes and the badger, whereas first-stage larvae were detected in the three dogs. All specimens were morphologically identified as C. vulpis, and 28 nematodes were also molecularly characterized by sequencing mitochondrial (12S ribosomal DNA (rDNA)) and nuclear (18S rDNA) ribosomal genes. Four haplotypes were identified based on the 12S rDNA target gene, with the most representative (78.5%) designated as haplotype I. No genetic variability was detected for the 18S rDNA gene. The molecular identification was consistent with the distinct separation of species-specific clades inferred by the phylogenetic analyses of both mitochondrial and ribosomal genes. Data herein reported indicates that C. vulpis has a wide distribution in foxes from southern Italy, and it also occurs in dogs from southern and northern regions of the country. Practitioners should consider the occurrence of this nematode in the differential diagnosis of canine respiratory disease, particularly in dogs living close to rural areas where foxes are present.

Morphometric, histopathological and molecular findings of Macracanthorhynchus hirudinaceus infection in wild boar (Sus scrofa) from continental Italy.

Although Macracanthorhynchus hirudinaceus is a neglected acanthocephalan of suids occasionally responsible for severe infections in humans, the spread of wild boar (Sus scrofa) populations in Europe could promote the circulation. Herein, we report the first morphometric, histological and molecular characterization of a severe M. hirudinaceus infection in a boar from continental Italy. The boar's intestine displayed granulomatous enteritis due to 24 helminths (14 females, 10 males), identified as adults of M. hirudinaceus by a combined morphometric/molecular approach. The phylogenetic analysis of the cox1 gene revealed a close relationship of the M. hirudinaceus sequence type found herein with those from Hungary and insular Italy. The high haplotype diversity and low nucleotide diversity of M. hirudinaceus specimens would suggest its rapid demographic expansion in the Mediterranean basin. More research is needed to assess the presence of M. hirudinaceus in susceptible beetle species and the role of boars in the epidemiology of infection.

Trichinella spp. in wolves (Canis lupus) and red foxes (Vulpes vulpes) of southern Italy.

Trichinella spp. are cosmopolitan parasites that infect a wide range of hosts, with wildlife being the main reservoir of these zoonotic nematodes, especially red foxes (Vulpes vulpes) and wolves (Canis lupus) due to their apex position in the food chain in most European countries. The aim of this study is to investigate the prevalence of Trichinella spp. in these wild canids and their epidemiological role in the Campania region (southern Italy). From 2017 to 2023, the carcasses of red foxes (n = 352) and wolves (n = 41) were collected as part of a health surveillance plan. Muscle samples were analysed individually by artificial digestion and four (1.1%) red foxes and nine (21.9%) wolves tested positive for Trichinella britovi. All Trichinella isolates were identified as T. britovi by multiplex PCR. Statistically significant differences in prevalence were found by province (p-value = 0.05) for red foxes and sampling years (p-value = 0.01) for wolves. The prevalence was lower in red foxes than in wolves, probably due to the longer life expectancy of wolves compared to red foxes and the role of wolves as apex predators compared to red foxes as meso-carnivores. The results obtained confirm the important role that these wild canids play in the circulation of the parasite.

First molecular detection of Babesia vulpes and Babesia capreoli in wild boars from southern Italy.

Introduction: Following the increase of wild boar (Sus scrofa) populations in Europe, a potential risk of emerging infections by vector-borne pathogens may occur. Despite this, the circulation of piroplasmid species in these ungulates is still a neglected topic, particularly in the Mediterranean basin. Therefore, this study aimed to investigate the presence of Babesia/Theileria spp. in wild boars from southern Italy to assess the epidemiological role of these ungulates in the circulation of piroplasmids. Methods: By using a citizen science approach among hunters and veterinarians, wild boar spleen samples were collected in the Campania region (southern Italy) between 2016 and 2022. A combined semi-nested PCR/sequencing analysis targeting the V4 hyper-variable region of 18S rRNA was run to detect Babesia/Theileria spp. DNA. Results: Out of 243 boars, 15 (i.e., 6.2, 95% CI: 3.4-9.9) tested positive to Babesia/Theileria spp., Babesia vulpes (n = 13, 5.3, 95% CI: 3.1-8.9) the most prevalent, followed by Babesia capreoli (n = 2, 0.8, 95% CI: 0.2-2.9). Three different B. vulpes sequence types were identified (i.e., ST1, ST2, ST3), with the most representative as ST1 (60%), and a single B. capreoli sequence type. No statistically significant difference (p > 0.05) were found between the presence of the pathogens and boar age, sex, province and sample collection year. Discussion: Data demonstrate for the first time the occurrence of B. vulpes and B. capreoli in wild boars, which may play a role in the biological cycle of piroplasmids. We emphasize the importance of monitoring these ungulates to prevent potential foci of infection. The engagement of hunters in epidemiological scientifically based surveys can constitute a technically sound control strategy of piroplasmids in a One Health perspective.

Molecular differentiation of Sarcocystis miescheriana and Sarcocystis suihominis using a new multiplex PCR targeting the mtDNA cox1 gene in wild boars in southern Italy.

The increase of wild boar populations density and their meat consumption across Europe could expose humans to a plethora of foodborne diseases as sarcocystosis, caused by the zoonotic protozoan Sarcocystis suihominis. Humans become infected by eating raw or undercooked pig (Sus scrofa domesticus) containing S. suihominis sarcocysts. Despite this, to date very few data are available on the risk of infection by this parasite to wild boar (Sus scrofa) meat consumers. Thus, the present study aimed to assess the occurrence of Sarcocystis spp. in wild boars from southern Italy, applying both histology and a new multiplex PCR assay targeting the cox1 gene. Between 2019 and 2020, 997 muscle tissues (i.e., n = 269 oesophagus, n = 277 diaphragms, n = 298 hearts, n = 153 tongues) from 311 wild boars were collected and screened by a combined histological and molecular approach. Overall, 251 (80.7%) animals tested were positive for Sarcocystis spp., and S. miescheriana whose definitive hosts are canids, was the only molecularly identified species. A statistically significant difference (p < 0.05) in the prevalence of Sarcocystis infection was found according to the wild boar age and muscle tissue. Findings outlined the low zoonotic potential of infection to humans via wild boar meat consumption in Italy and the importance of the application of new molecular methods in distinguishing different Sarcocystis species.

Detection at high prevalence of newlavirus (protoparvovirus) in the carcasses of red foxes.

Wildlife conservation also relies on the study of animal virome. We identified the DNA of a novel fox protoparvovirus, newlavirus, with high (71%) prevalence in the carcasses of red foxes. On genome sequencing, high genetic diversity and possible recombination was observed, suggesting complex evolutionary dynamics in wildlife.

Trichinella britovi in wild boar meat from Italy, 2015-2021: A citizen science approach to surveillance.

As a result of the increase of game meat intended for human consumption through Europe, a plethora of food-borne diseases, including trichinellosis, may occur in consumers, posing a relevant public health threat. Thus, this study aims to a citizen science approach to monitor the occurrence of Trichinella spp. in wild boar meat intended for human consumption, evaluating the risk of infection for consumers. Following the European Regulation 2015/1375 (laying down specific rules on official controls for Trichinella in meat), from 2015 to 2021, hunters (n = 478) were involved to collect diaphragm pillar samples of wild boars from mainland southern Italy, which were tested for Trichinella spp. L1 larvae via HCl-pepsin digestion and Multiplex PCR. Overall, 139,160 animals were collected (average of 19,880 per year), being 14 (i.e., 0.01%) tested positive to Trichinella britovi by the combined biochemical and molecular approach. An average larval burden of 28.4 L1 per gram of meat was found (minimum 3.2 - maximum 132.6). A statistically significant difference was found in the prevalence according to hunting seasons (p < 0.01, with higher values in 2016 and 2021) and regions of the study area (p < 0.01). No statistically significant decrease in the prevalence of T. britovi throughout the study period was found (p = 0.51), except in Apulia region (p < 0.01). These findings revealed a stable prevalence of T. britovi in wild boar meat intended for human consumption, suggesting a risk of infection for consumers, especially hunters and local markets users. Citizen science surveillance models could be promoted to improve trichinellosis control and prevention in a One Health perspective.

Molecular Survey of Toxoplasma gondii in Wild Mammals of Southern Italy.

Systematic wildlife surveillance is important to aid the prevention of zoonotic infections that jeopardize human health and undermine biodiversity. Toxoplasma gondii is an opportunistic zoonotic protozoan that can infect all endothermic vertebrates, causing severe disease in immunocompromised humans and cases of congenital transmission. Humans can be infected by ingestion of raw meat containing bradyzoites or water contaminated by oocysts. In our study, we assessed the potential circulation of Toxoplasma gondii in wild mammals by performing surveillance in the Campania region (southern Italy) and surveyed its presence from 2020 to 2022 within the framework of the Regional Plans for Wildlife Surveillance. In detail, 211 individuals belonging to five wild mammals (wolf, fox, wild boar, badger, and roe deer) underwent necropsy and the organs were analyzed by real-time PCR for the detection of the parasite. Toxoplasma gondii was found in 21.8% (46/211) of the subjects examined. No statistically significant differences were noticed between the prevalence and the host's trophic level or age, rejecting the hypotheses that Toxoplasma gondii will have a higher prevalence in top predators and adult individuals, respectively. Our work emphasized the high circulation of Toxoplasma gondii in wildlife and remarked on the critical role of anthropized areas where domestic cats and wildlife may come into contact, urging a systematic surveillance.

First identification of bovine hepacivirus in wild boars.

Hepatitis C virus (HCV) is a major cause of chronic hepatitis, cirrhosis and hepatocellular carcinoma in humans. Humans were long considered the only hosts of Hepacivirus. Recently HCV-like sequences have been found in several animal species. Hepaciviruses are considered species-specific but a wider host range and a zoonotic role has been hypothesized. We report the first detection of bovine hepacivirus (BovHepV) sequences in wild boars. A total of 310 wild boars hunted in Campania region were investigated with a pan-hepacivirus nested-PCR protocol for the NS3 gene. Hepacivirus RNA was detected in 5.8% of the animals. Sequence and phylogenetic analysis showed high homology with BovHepV subtype F, with nucleotide identity of 99%. The positive wild boars were georeferenced, revealing high density of livestock farms, with no clear distinction between animal husbandry and hunting areas. These findings might suggest the ability of BovHepV to cross the host-species barrier and infect wild boars.

Presence of enteric bacterial pathogens in meat samples of wild boar hunted in Campania region, southern Italy.

Wild boars can be infected with several foodborne pathogens which may be transmitted to humans through the consumption of their meat, but currently, data of their prevalence are still limited. The present study aimed to evaluate the presence of enteric pathogens in wild boar meat samples killed in the Campania region. Twentyeight wild boar meat samples were analyzed for the detection of Salmonella spp, Y. enterocolitica, Campylobacter spp., and Shiga- Toxigenic E. coli. Salmonella spp. was detected and isolated in ten samples and after serotyping S. Veneziana, S. Kasenyi, S. Coeln, S. Manhattan, S. Thompson, and S. Stanleyville were identified. Twenty-one meat samples were found to be contaminated with Y. enterocolitica; in 6 samples the ystA and ystB genes were detected simultaneously, while in 15 only the ystB gene, which characterizes the bacteria belonging to the biotype 1A, was present. Shiga-Toxin producing E. coli was detected in 12 while Campylobacter spp was never detected. In conclusion, due to the high occurrence of pathogenic bacteria detected, the present research shows that wild boars are important reservoirs for foodborne zoonoses which may be transmitted to livestock and humans. This confirms the importance of controls throughout the wild boar supply chain. In the Campania region, checks are guaranteed by the Veterinarians who work within the "management and control plan for wild boar in the Campania region" which has the twofold objective of containing the increasingly invasive presence of this animal and guaranteeing greater safety, traceability, and transparency in the consumption of meat.

Canine Distemper Virus in Autochtonous and Imported Dogs, Southern Italy (2014-2021).

This study aims to investigate the presence of canine distemper virus (CDV) infection in 949 autochthonous or illegally imported dogs from Southern Italy, over a period of eight years (2014-2021). CDV RNA was detected in 6.8% (65/949) of the animals tested, with no detection of CDV in dogs sampled in 2020-2021. The frequency of CDV detection was higher in imported dogs (19/103, 18.3%) with respect to stray (27/365, 7.4%) and household dogs (19/481, 3.9%). On sequence and phylogenetic analyses of selected strains, the analyzed viruses belonged to the Arctic clade, which has already been reported in Italy and in Europe. The results of our study may suggest a reduction of CDV circulation in Southern Italy, while at the same time highlighting the need for strict controls on dog importation, in order to prevent the introduction of viruses from endemic countries.

Molecular Epidemiology of Ovine Papillomavirus Infections Among Sheep in Southern Italy.

Ovine papillomaviruses (OaPVs) were detected and quantified, for the first time, using droplet digital polymerase chain reaction (ddPCR) and real-time quantitative PCR (qPCR) via blood samples of 165 clinically healthy sheep. OaPV DNA was detected in 126 blood samples (~76.4%). DdPCR detected OaPV DNA in 124 samples; in only two additional samples positive for real-time qPCR, ddPCR failed to detect the presence of any OaPVs. In 70 of the positive samples (~55.6%), a single OaPV infection was observed, 12 of which were caused by OaPV1 (~17.1%) and 14 by OaPV2 (20%). OaPV3 was responsible for 19 single infections (~27.1%), and OaPV4 for 25 single infections (~35.7%). Multiple OaPV coinfections were observed in 56 (~44.4%) positive samples. OaPV coinfections caused by two genotypes were observed in 31 positive samples (~55.4%), with dual OaPV3/OaPV4 infection being the most prevalent as seen in 11 blood samples. In addition, five OaPV1/OaPV4, four OaPV1/OaPV2, four OaPV2/OaPV3, four OaPV1/OaPV3, and three OaPV2/OaPV4 dual coinfections were also detected. OaPV coinfections by triple and quadruple genotypes were detected in 24 (~42.8%) and only one (~1.8%) of coinfected blood samples, respectively. Multiple infections caused by OaPV1/OaPV3/OaPV4 genotypes were the most prevalent, as observed in 12 (50%) blood samples harboring triple OaPV infections. This study showed that ddPCR is the most sensitive and accurate assay for OaPV detection and quantification thus outperforming real-time qPCR in terms of sensitivity and specificity. Therefore, ddPCR may represent the molecular diagnostic tool of choice, ultimately providing useful insights into OaPV molecular epidemiology and field surveillance.