PREVALENCE, INCIDENCE, AND IDENTIFICATION OF SALMONELLA ENTERICA FROM WILD AND CAPTIVE GRAND CAYMAN IGUANAS ( CYCLURA LEWISI)

Epidemiology of Salmonella enterica subspecies enterica serotypes, isolated from imported, farmed and feral poultry in the Cayman Islands

Non-typhoidal Salmonellae (NTS) are common foodborne pathogens throughout the world causing acute gastroenteritis. Compared to North America and Europe, there is little information on NTS in the Caribbean. Here we investigated the prevalence and characteristics of NTS present in the local poultry of the Cayman Islands to determine the public health risk. In total, we collected 156 samples. These were made up of boot swabs of 31 broiler farms and 31 layer farms (62 samples), paper bedding from 45 imported chick boxes, and 49 pooled cecum samples from feral chickens, each sample representing 10 individual chickens. Salmonella was isolated using the ISO 6579 protocol and isolates were characterized using Whole Genome Sequencing (WGS) analysis. Eighteen Salmonella isolates were obtained and comprised six S. enterica subspecies enterica serotypes and one subspecies houtenae serotype. Serotypes were: S. Kentucky (n = 9), S. Saintpaul (n = 5), S. Javiana (n = 1), S. Senftenberg (n = 1), S. Poona (n = 1) and S. Agona (n = 1). S. Kentucky strains were all ST152 and clonally related to poultry strains from the United states. S. Saintpaul ST50 strains showed clonality to North American strains. Over half of the strains (n = 11) contained resistance genes to at least two antibiotic groups and five strains were MDR, mainly those from imported day-old chicks. The blaCMY-2 gene was found in S. Kentucky from day-old chicks. Strains from feral poultry had no acquired AMR genes. While serotypes from feral poultry have been identified in human infections, they pose minimal risk due to their low virulence.

HELICOBACTER SCREENING OF GRAND CAYMAN BLUE IGUANA (CYCLURA LEWISI) AND NORTH ANTILLEAN SLIDER (TRACHEMYS DECUSSATA ANGUSTA) ON GRAND CAYMAN, CAYMAN ISLANDS

The endemic Grand Cayman or blue iguana (Cyclura lewisi) is endangered. Beginning in 2015 significant morbidity and mortality occurred in captive and wild blue iguanas within Grand Cayman's Queen Elizabeth II Botanic Park (QEIIBP). Investigation identified a novel Helicobacter sp., provisionally named Helicobacter sp. Grand Cayman Blue Iguana 1 (GCBI1), as the cause. Invasive green iguanas (Iguana iguana) are believed to play a role in GCBI1 transmission to the blue iguana; however, the origin and transmission pathways have not been determined. To assess the likelihood of blue iguanas asymptomatically harboring GCBI1, in May 2022 population-level screening of captive blue iguanas at QEIIBP was conducted on half (n = 102) of the captive blue iguana population (n = 201) including half of each age class. Helicobacter sp. GCBI1 is closely related to a chelonian Helicobacter sp. and 10 sympatric wild north Antillean sliders (Trachemys decussata angusta) were sampled in October 2019. Combined choana/cloacal swabs were screened by a GCBI1-specific quantitative polymerase chain reaction (qPCR) assay. All samples were negative, suggesting that GCBI1 is not present asymptomatically in the captive blue iguana population or in north Antillean sliders. These results provide support for the hypothesis that GCBI1 is periodically introduced to captive and wild blue iguanas from another species or source.

BURMESE ROOFED TURTLE (BATAGUR TRIVITTATA) DISEASE SCREENING IN MYANMAR

The Burmese roofed turtle (Batagur trivittata), a critically endangered freshwater turtle, is endemic to Myanmar. Once thought to be extinct, remnant wild populations were discovered in 2001 and limited captive individuals identified in pagoda ponds or confiscated from fishers in Myanmar. These and their offspring are maintained in five facilities in Myanmar and form the basis of a conservation program (habitat protection, captive breeding, nest protection, egg collection, head-starting, and release). Prerelease health screenings were performed in 2014 and 2018 at Yadanabon Zoological Gardens, a head-starting facility in Limpha Village, and Lawkanandar Wildlife Park. One hundred forty-three turtles were assessed (37 male, 50 female, 56 juveniles [too young to determine sex]; two females were assessed in both years), age range of 1 to 12 y (one unknown age adult founder), and body mass range of 0.111 to 32.72 kg. Health evaluations both years included physical examination and combined choanal/cloacal swab samples for polymerase chain reaction testing of the potential chelonian pathogens intranuclear coccidia, Mycoplasma, Herpesvirus, Ranavirus, and Adenovirus (not all tests performed each year). In 2018, cloacal swabs from 30 and 20 turtles at the Yadanabon Zoological Gardens and Lawkanandar Wildlife Park, respectively, were cultured for Salmonella. All turtles were assessed as healthy based on normal physical examination findings, and all had negative test results. Prerelease health screening, such as performed in this study, is an important component of release, reintroduction, and translocation projects to prevent introduction of novel pathogens into naïve wild populations.

Salmonella in Pig Farms and on Pig Meat in Suriname

Salmonella is one of the most important food borne zoonotic pathogens. While mainly associated with poultry, it has also been associated with pigs. Compared to the high-income countries, there is much less known on the prevalence of Salmonella in low- and middle-income countries, especially in the Caribbean area. Therefore, we investigated the prevalence of Salmonella in pigs and pig meat in Suriname. A total of 53 farms and 53 meat samples were included, and Salmonella was isolated using standard protocols. Strains were subjected to whole genome sequencing. No Salmonella was found on pig meat. Five farms were found to be positive for Salmonella, and a total of eight different strains were obtained. Serotypes were S. Anatum (n = 1), S. Ohio (n = 2), a monophasic variant of S. Typhimurium (n = 3), one S. Brandenburg, and one S. Javaniana. The monophasic variant of S. Typhimurium belonged to the ST34 pandemic clone, and the three strains were very similar. A few resistance genes, located on mobile genetic elements, were found. Several plasmids were detected, though only one was carrying resistance genes. This is the first study on the prevalence of Salmonella in pigs in the Caribbean and that used whole genome sequencing for characterization. The strains were rather susceptible. Local comparison of similar serotypes showed a mainly clonal spread of certain serotypes.

Zoonotic potential and prevalence of Salmonella serovars isolated from pets

Salmonellosis is a global health problem, affecting approximately 1.3 billion people annually. Most of these cases are related to food contamination. However, although the majority of Salmonella serovars are pathogenic to humans, animals can be asymptomatic carriers of these bacteria. Nowadays, a wide range of animals is present in human households as pets, including reptiles, amphibians, dogs, cats, ornamental birds, and rodents. Pets contaminate the environment of their owners by shedding the bacteria intermittently in their feaces. In consequence, theyare thought to cause salmonellosis through pet-to-human transmission. Each Salmonella serovar has a different zoonotic potential, which is strongly regulated by stress factors such as transportation, crowding, food deprivation, or temperature. In this review, we summarize the latest reports concerning Salmonella-prevalence and distribution in pets as well as the risk factors and means of prevention of human salmonellosis caused by contact with their pets. Our literature analysis (based on PubMed and Google Scholar databases) is limited to the distribution of Salmonella serovars found in commonly owned pet species. We collected the recent results of studies concerning testing for Salmonella spp. in biological samples, indicating their prevalence in pets, with regard to clinical cases of human salmonellosis.

Systemic Helicobacter infection and associated mortalities in endangered Grand Cayman blue iguanas (Cyclura lewisi) and introduced green iguanas (Iguana iguana)

The Blue Iguana Recovery Programme maintains a captive breeding and head-starting program for endangered Grand Cayman blue iguanas (Cyclura lewisi) on Grand Cayman, Cayman Islands. In May 2015, program staff encountered two lethargic wild Grand Cayman blue iguanas within the Queen Elizabeth II Botanic Park (QEIIBP). Spiral-shaped bacteria were identified on peripheral blood smears from both animals, which molecular diagnostics identified as a novel Helicobacter species (provisionary name Helicobacter sp. GCBI1). Between March 2015 and February 2017, 11 Grand Cayman blue iguanas were identified with the infection. Two of these were found dead and nine were treated; five of the nine treated animals survived the initial infection. Phylogenetic analysis of the 16S rRNA gene suggests Helicobacter sp. GCBI1 is most closely related to Helicobacter spp. in chelonians. We developed a Taqman qPCR assay specific for Helicobacter sp. GCBI1 to screen tissue and/or blood samples from clinical cases, fecal and cloacal samples from clinically healthy Grand Cayman blue iguanas, including previously infected and recovered iguanas, and iguanas housed adjacent to clinical cases. Fecal and/or cloacal swab samples were all negative, suggesting that Grand Cayman blue iguanas do not asymptomatically carry this organism nor shed this pathogen per cloaca post infection. Retrospective analysis of a 2014 mortality event affecting green iguanas (Iguana iguana) from a separate Grand Cayman location identified Helicobacter sp. GCBI1 in two of three cases. The source of infection and mode of transmission are yet to be confirmed. Analysis of rainfall data reveal that all infections occurred during a multi-year dry period, and most occurred shortly after the first rains at the end of seasonal drought. Additionally, further screening has identified Helicobacter sp. GCBI1 from choanal swabs of clinically normal green iguanas in the QEIIBP, suggesting they could be asymptomatic carriers and a potential source of the pathogen.

PARASITES OF THE BLUE IGUANA (CYCLURA LEWISI) FROM GRAND CAYMAN ISLAND

Feces (n = 226; 2004-2015) from healthy captive and wild blue iguanas (Cyclura lewisi) from Grand Cayman, Cayman Islands, were examined for endoparasites. Parasites identified included Nyctotherus sp. and Entamoeba sp. cysts and trophozoites, trichomonad trophozoites, and oxyurid and trichostrongylid eggs. Endoparasites from postmortem examinations (n = 13) included adult and larval nematodes: Ozolaimus megatyphlon, Ozolaimus monhystera, Alaeuris travassosi, Atractis mega, and an unidentified species of Oswaldocruzia. Entamoeba spp. were more likely in captive juveniles of both sexes than captive or wild adults of either sex; Entamoeba spp. were more likely in captive adult females than captive adult males; trichomonad trophozoites were more likely in adult captive and wild iguanas of both sexes than in captive juveniles of either sex; and Nyctotherus spp. were more likely in juvenile captive males than captive adult males or females and more likely in adult wild males than captive juvenile males. Trichostrongylid eggs were more likely in adult wild females than adult captive females and more likely in captive and wild adults of both sexes than in captive juveniles of both sexes. Oxyurid eggs were more likely in adult captive and wild iguanas of both sexes than captive juveniles of either sex. Blue iguanas have a variety of endoparasites regardless of age, sex, or captive vs wild status, with no type found exclusively in either captive or wild populations. Ectoparasites from wild adults included adult ticks (Amblyomma torrei) and a single adult mite (Hirstiella trombidiformis). All are new host records for this species and Grand Cayman. Knowledge of parasite status of captive and wild populations is important to evaluate the relative risk of introduction of captive animals into wild populations.