Survey of co-infection by Salmonella and oxyurids in tortoises

Epidemiological survey of gastrointestinal helminths and protozoa in Testudines from Sardinia, Italy

The order Testudines comprises some of the most endangered groups of vertebrates. Under specific circumstances, infectious and parasitic diseases may affect the survival and fecundity of these animals, potentially threatening Testudines populations. In Sardinia, besides the three species of tortoises present in the wild (Testudo hermanni, Testudo graeca and Testudo marginata), many others are kept as pets. However, epidemiological studies on these animals have not been conducted so far. Thus, the aim of the work was to investigate the presence of gastrointestinal parasites in captive and wild tortoises of Sardinia, Italy, with particular regard to those of zoonotic importance. For the 215 animals examined (n = 36 wild caught and n = 179 private-owned), fecal samples were collected and processed by flotation and modified Ziehl-Neelsen technique. An overall prevalence of 81.4% for endoparasites was detected, with oxyurids being the most prevalent (74.4%), followed by Nyctotherus spp. (18.6%), Cryptosporidium spp. (12.6%), Angusticaecum spp. (2.8%), strongyles (0.9%), Balantidium spp. (0.9%), coccidia (0.9%), cestodes (0.5%), and Giardia spp. (0.5%). Data suggest that tortoises are affected by a great variety of endoparasites, and further molecular analysis are required to assess the impact of Cryptosporidium and Giardia species in these hosts. Therefore, regular health screenings are of importance for the management of these animals and for preventing emerging infectious diseases.

Surveys on Exposure to Reptile-Associated Salmonellosis (RAS) in the Piedmont Region—Italy

Simple Summary

Reptile-associated salmonellosis (RAS), Salmonella infection (salmonellosis) in humans, is acquired through contact both directly with reptiles and indirectly with their environment. In Italy, like in other countries, reptiles have become popular pet animals, but epidemiological data about RAS are not collected. To fill this gap, surveys to estimate the presence and frequency of RAS and human exposure were carried out in Piedmont, a Northern-Italian region. Two studies were conducted among patients with sporadic salmonellosis (i.e., not linked to foodborne outbreaks): the first, restricted to a big city hospital, showed a prevalence of RAS of 7%, and the second, extending to the population affected by sporadic salmonellosis across all the region, showed a prevalence of 3%. In addition, an ocular survey taken in public places displaying reptiles detailed possible exposure through direct and indirect contact and a questionnaire survey that collected data from the general population, including reptile owners, revealed that preventive measures are not always known or applied. These results confirmed that RAS in Italy is present and constitutes a proportion of the human salmonellosis cases in line with the percentages reported in other countries. People should be more informed about RAS and the related preventive measures.

Abstract

Reptile-associated salmonellosis (RAS), Salmonella infection in humans, is acquired through contact with reptiles. Reptiles have become popular pet animals, and RAS is likely to be an underestimated but growing problem. No epidemiological data about RAS are routinely collected in Italy. In order to estimate the occurrence of RAS in the Italian human population and to investigate the exposure, two epidemiological studies on patients with sporadic salmonellosis were carried out in the Piedmont region, along with an evaluation of human exposure in public places displaying reptiles and with a survey on people awareness. RAS appeared make up 7% of sporadic salmonellosis in the first study and 3% in the second, more extensive study. A prevalence of 11.7% and 5.7%, respectively, were calculated for the age range of 0–21 years. It was observed that in public places displaying reptiles, it was possible to easily come into contact with the animals and their environment. Some knowledge about RAS emerged from the interviews with the general population, but preventive measures are not completely applied by reptile owners. In conclusion, RAS in Italy is present and constitutes a proportion of the human salmonellosis cases in line with the percentages reported in other countries. Exposure to reptiles should always be considered as a risk factor, and people should be more informed about RAS and the related preventive measures.

Salmonella Infection in Turtles: A Risk for Staff Involved in Wildlife Management?

Simple Summary

The aim of this study was to investigate the occurrence of non-typhoidal Salmonella in the turtles housed in a regional wildlife rescue centre of Apulia, in southern Italy, to assess the presence of Salmonella serovars that may represent a risk for operators involved in wildlife management. Sixty-nine tortoises, of which 36 were males and 33 were females, belonging to different species (Testudo hermanni hermanni, T. h. boettgeri, T. graeca, and T. marginata) were tested. All the turtles were adults (34 between 6 and 10 years of age and 35 more than 10 years of age). Salmonella was statistically detected more frequently in T. hermanni hermanni. No differences of the infection prevalence related to animal gender or age were found. Two different species, S. enterica and S. bongori, three S. enterica subspecies (enterica, diarizonae, salamae), and five different serovars (Hermannswerder, Abony, Ferruch, Richmond, Vancouver) within the group S. enterica subspecies enterica were identified. Two Salmonella types with different combinations were simultaneously found in specimens of T. h. hermanni. Most of the detected Salmonella types may represent a potential risk for operators in wildlife rescue centres.

Abstract

Monitoring of infections that may be transmitted to humans by animals in wildlife rescue centres is very important in order to protect the staff engaged in rehabilitation practices. Salmonella may be a natural inhabitant of the intestinal tract of turtles, rarely causing disease. This may represent a potential risk for humans, increasing the sanitary risk for operators in wildlife rescue centres. In this paper, the occurrence of non-typhoidal Salmonella among terrestrial turtles housed in a wildlife rescue centre in Southern Italy was investigated, in order to assess the serovars more frequently carried by turtles and identify those that may represent a risk for operators involved in wildlife management. Sixty-nine adult turtles (Testudo hermanni hermanni, T. h. boettgeri, T. graeca, and T. marginata) were tested. Detection and serotyping of Salmonella strains were performed according to ISO 6579-1 and ISO/TR 6579-3:2013, respectively. The distribution of Salmonella spp. was significantly higher in T. hermanni hermanni than in other species, independent of the age and gender of the animals. Two different Salmonella species, S. enterica and S. bongori, three S. enterica subspecies (enterica, diarizonae, salamae), and five different serovars (Hermannswerder, Abony, Ferruch, Richmond, Vancouver) within the group S. enterica subspecies enterica were identified. Different combinations of Salmonella types were simultaneously found in specimens of T. h. hermanni. Most of detected Salmonella types may represent a potential risk for public health. Adopting correct animal husbandry procedures and informing on potential sanitary risks may be useful for minimising the risk of transmission of Salmonella to workers involved in wildlife management.

CHARACTERIZING THE EPIDEMIOLOGY OF HISTORIC AND NOVEL PATHOGENS IN BLANDING'S TURTLES (EMYDOIDEA BLANDINGII)

Pathogens such as herpesviruses, Mycoplasma spp., and frog virus 3-like ranavirus have contributed to morbidity and mortality in many species of free-living and zoo-maintained chelonians. However, their prevalence is understudied in Blanding's turtles (Emydoidea blandingii) across North America. To assess the presence of these pathogens, Blanding's turtles were sampled in Lake County, Illinois, in 2017 (N = 213) and 2018 (N = 160). DNA from cloacal-oral swabs was assayed for four ranaviruses, three Mycoplasma spp., two Salmonella spp., Emydoidea herpesvirus 1 (EBHV1), and tortoise intranuclear coccidiosis (TINC) using a multiplex quantitative polymerase chain reaction (qPCR). Pathogens were most frequently detected in adult turtles (n = 25) and rarely in subadults (n = 2) or juveniles (n = 1). EBHV1 was detected in 22 individuals with no clinical signs of illness, most (n = 20) occurring in the month of May (P < 0.0001). EBHV1 cases at one study site significantly clustered within the same 0.64-km area from 17 to 22 May 2017 (P < 0.0001) and 14 to 15 May 2018 (P = 0.0006). Individuals were rarely positive for Salmonella typhimurium (n = 6). A novel Mycoplasma sp. sharing high homology with other emydid Mycoplasma spp. was detected in one turtle with nasal discharge. Neither TINC nor any ranaviruses were detected. Continued monitoring of this population and habitat may facilitate identification of risk factors for pathogen occurrence and clarify the impact of infectious diseases on Blanding's turtle conservation outcomes.

Health assessment of wild speckled dwarf tortoises, CHERSOBIUS SIGNATUS

BACKGROUND

In free-ranging reptile populations, bacterial, fungal, viral and parasitic pathogens may affect hosts through impairment in movements, thermoregulation, reproduction, survival, and population dynamics. The speckled dwarf tortoise (Chersobius [Homopus] signatus) is a threatened species that is mostly restricted to the Succulent Karoo biome in South Africa, and little information on pathogens of this species is available yet. We derived baseline parameters for five males and five females that were captured to genetically enhance a conservation breeding program in Europe. Upon collection of the tortoises, ticks were removed and identified. Immediately upon arrival in Europe, ocular, nasal, oral and cloacal swabs were taken for viral, bacteriological and mycological examinations. Fecal samples were collected before and 1 month after fenbendazole treatment, and analyzed for parasites. A panel of PCR, aiming to detect herpesviruses, adenoviruses and iridoviruses, was carried out.

RESULTS

Samples were negative for viruses, while bacteriological examination yielded detectable growth in 82.5% of the swabs with a mean load of 16 × 107 ± 61 × 108 colony forming units (CFU) per swab, representing 34 bacterial species. Cloacal and oral swabs yielded higher detectable growth loads than nasal and ocular swabs, but no differences between sexes were observed. Fungi and yeasts (mean load 5 × 103 ± 13 × 103 CFU/swab) were detected in 25% of the swabs. All pre-treatment fecal samples were positive for oxyurid eggs, ranging from 200 to 2400 eggs per gram of feces, whereas after the treatment a significantly reduced egg count (90-100% reduction) was found in seven out of 10 individuals. One remaining individual showed 29% reduction, and two others had increased egg counts. In five tortoises, Nycthocterus spp. and coccidian oocysts were also identified. Soft ticks were identified as Ornithodoros savignyi.

CONCLUSIONS

Our baseline data from clinically healthy individuals will help future studies to interpret prevalences of microorganisms in speckled dwarf tortoise populations. The study population did not appear immediately threatened by current parasite presence.

First multicenter coprological survey on helminth parasite communities of free-living loggerhead sea turtles Caretta caretta (Linnaeus, 1758) from the Adriatic Sea and Northern Ionian Sea

The prevalence of endoparasite infections in 83 free-living specimens of Caretta caretta, classified as vulnerable species, from the Adriatic Sea and Northern Ionian Sea was investigated by coprological examination. Thirty-seven (44.6%) turtles were found to be infected with helminths. The helminth infections found were: Rhytidodes gelatinosus and Sulcascaris sulcata (18.1% each), Hapalotrema mistroides (13.2%), Cymatocarpus solearis (9.6%), Eniodotrema megachondrus (7.2%), Kathlania/Tonaudia sp. (3.6%), Neospirorchis sp., Octangium sagitta and Plesiochorus cymbiformis (1.2% each). There were no significant differences in the total prevalence of helminth infections between sexes, size classes, and seasonal periods. Conversely, the prevalence of helminth infections was significantly higher (P < 0.01) in accidentally caught turtles than in stranded turtles. Highly significant differences in prevalence of helminthiases were also seen among marine sampling areas. This report provides important baseline information about the helminth fauna of free-living C. caretta in the examined geographical region. This is also the first report of O. sagitta infection in C. caretta thus broadening the host range of the parasite.

Plasma antibacterial activities in ornate (Terrapene ornata) and eastern box turtles (Terrapene carolina)

Chelonians are one of the most imperiled vertebrate taxa and many species are increasingly threatened by disease, however, the immune response in this group is understudied. We quantified the innate immune response of eastern (Terrapene carolina; EBT) and ornate (Terrapene ornate; OBT) box turtles using plasma antibacterial activity assays. Plasma from both species abolished or significantly reduced the growth of all eight bacterial species evaluated, including Salmonella typhimurium, Escherichia coli, Enterobacter cloacae, Citrobacter freundi, Bacillus subtilis, Staphylococcus epidermidis, and Staphylococcus aureus. Bactericidal capacity was greater in OBT compared to EBT, and OBT plasma retained high antibacterial activities at a broader temperature range (20-40°C) compared to EBT (30-40°C). Plasma antibacterial activity was abolished following treatment with heat, protease, and ethylenediaminetetraacetic acid, indicating that complement is likely responsible for the observed effects. Further characterization of the box turtle immune response may provide insight into the importance of infectious diseases for species conservation, enabling the development of more efficient and effective population management strategies.

Gastrointestinal investigation of parasites and Enterobacteriaceae in loggerhead sea turtles from Italian coasts

Background

Caretta caretta is the most abundant sea turtle species in the Mediterranean, and studies on this species have vastly expanded during recent years, including those investigating gut bacterial and parasitic communities. Members of these communities have been reported with variable prevalence and pathogenicity, mainly depending on their host and environment (e.g. lifespan, distribution, habitat, diet, health status and stressors). Indeed, many species commonly inhabiting the sea turtle gastrointestinal tract exhibit an opportunistic behaviour.

This study aimed to provide baseline data on enterobacterial and parasitic composition, through bacteriological culture-based methods and the FLOTAC parasitological technique, in cloacal and faecal samples of 30 live Caretta caretta, examined upon their arrival at the Marine Turtle Research Centre (Portici, Italy).

Results

Enterobacteriaceae were isolated in 18/23 cloacal samples (78.3%), with Citrobacter and Morganella as the most common genera, followed by Proteus, Enterobacter, Providencia, and Hafnia. Parasitic elements were detected in 11/30 faecal samples (36.7%), with Enodiotrema, Rhytidodes, and Eimeria as most common genera, followed by Pachypsolus and Cymatocarpus. Additionally, Angiodyctium is reported for the first time in this host. The majority (47.8%) of sea turtles hosted exclusively Enterobacteriaceae, whereas 30.4% hosted both parasites and Enterobacteriaceae; the remaining 21.8% hosted neither of the agents.

Conclusions

Bacteria and parasites evaluated in the present study are common in Mediterranean loggerhead sea turtles, with slight differences between the western and eastern basin. Although naturally present in the gastrointestinal system of free-living sea turtles, their relationship with these hosts might range from mutualism to parasitism. Indeed, members of the gut community might express their pathogenic potential in immune-compromised animals, such as those in rehabilitation facilities. Therefore, it is advisable to include in the standard work-up of rescued sea turtles a screening procedure for such opportunistic agents, in order to better evaluate the animal’s health status and achieve timely intervention with appropriate treatment, thus improving rehabilitation. Furthermore, data collected from free-living sea turtles represent a starting point for investigating wild populations. However, further studies are needed to clarify the differences between sea turtle’s normal gut microbiome and pathobiome.

Bacteria and parasites in Podarcis sicula and P. sicula klemmerii

Background

New epidemiological data on bacterial and parasitic infections in 24 Italian wall lizards, namely Podarcis sicula (mainland population) and P. sicula klemmerii (insular population) in southern Italy were provided. To achieve this goal, samples were collected from individuals belonging to the two populations and analysed by microbiological and parasitological methods.

Results

A wide range of bacteria (e.g. Pantoea spp., Citrobacter spp., Morganella spp., Pseudomonas, Enterobacter spp., Staphylococcus spp. and Escherichia coli) and parasites (e.g. Ophionyssus natricis, coccidia, Dicrocoelidae) were detected in both P. sicula and P. sicula klemmerii individuals. Insular population presented similar bacterial and parasitic diversity to its mainland counterpart. Ampicillin was the antimicrobial with the highest resistance rate.

Conclusion

This study highlighted various bacteria and parasites, some of them potentially zoonotic. Further studies are needed to better understand the epidemiology and transmission routes of these pathogens along with their impact on the welfare and behaviour of Italian wall lizards.

Considerations and conditions involving protozoal inhabitation of the reptilian gastrointestinal tract

In mammals, gastrointestinal protozoal organism inhabitation has been well studied, with hundreds of species defined as parasites. While the mammalian protozoal relationships have been identified and categorized by anatomy, tropism, pathogenicity, and life cycles, relatively few species of protozoal organism relationships have been categorized in reptiles. Species of parasites are still being segregated from each other, and conflicting information needs to be clarified to completely understand the data already available. This article presents the information available to help reptile practitioners make evidence-based decisions regarding both the determination of a pathologic parasitic condition and direct appropriate treatment of patients.

Oral flora of Python regius kept as pets

This study was aimed at evaluating the oral bacterial flora of 60 Python regius kept as pets by culture and biochemical methods. All isolates were also submitted to antimicrobial susceptibility testing using the disc diffusion method. The oral cavity of snakes sampled harboured a wide range of Gram-negative bacteria mainly constituted by Pseudomonas spp., Morganella morganii, Acinetobacter calcoaceticus, Aeromonas hydrophila, but also by Salmonella spp. Staphylococcus spp. was the commonest Gram-positive isolates, and various anaerobic Clostridium species were also found. The most effective antimicrobial agents were enrofloxacin and ciprofloxacin, followed by doxycycline and gentamicin.

SIGNIFICANCE AND IMPACT OF THE STUDY

The oral cavity of snakes sampled harboured a wide range of bacteria. Our results suggest that people who come in contact with snakes could be at risk of infection and should follow proper hygiene practices when handling these reptiles.

Co-infection by Escherichia coli O157 and gastrointestinal strongyles in sheep

This research investigated the prevalence of gastrointestinal (GI) strongyles and Escherichia coli O157 in naturally infected sheep, as well as the possible correlation between the pathogens examined. A total of 314 sheep, randomly selected from 21 farms located in southern Italy, were examined. GI strongyles and E. coli O157 were detected by using the FLOTAC double technique and culture media, respectively. GI strongyles were detected on 19/21 farms (90.5%) and E. coli O157 on 12/21 (57.4%). At the animal level, GI strongyles were detected from 193/314 (61.5%) sheep analysed, whereas E. coli O157 was isolated from 20/314 (6.4%) sheep. Statistical analysis performed at animal-level showed a negative correlation between E. coli O157 and GI strongyle EPGs (Spearman's ρ=-0.128; P=0.03). Caution should be exercised in interpreting the research findings because a number of different confounding factors possibly influenced the trend of negative correlation between the two pathogenic agents investigated. Further studies, including molecular diagnostics, production data and multivariable analytical approaches, are needed to assess the actual impact of multiple pathogen infections in grazing sheep and other livestock species.

Prevalence and molecular identification of Cryptosporidium isolates from pet lizards and snakes in Italy

In order to acquire prevalence and genetic data on Cryptosporidium infections in captive lizards and snakes kept as pets, a survey was conducted on 150 individual reptiles from southern Italy. Fecal samples were preserved in 5% formalin and analyzed using a commercial immunofluorescence assay (IFA) for the detection of Cryptosporidium oocysts and Giardia cysts. IFA revealed the presence of Cryptosporidium oocysts in nine of the 150 samples examined (6.0%), precisely in 6/125 snakes (4.8%) and in 3/25 lizards (12.0%); all fecal samples tested negative for the presence of Giardia cysts. Molecular characterization based on nested PCR amplification and sequencing of the SSU-rRNA gene, revealed the presence of Cryptosporidium serpentis in three samples from snakes (Boa constrictor constrictor, Elapheguttata guttata guttata and Python molurus).