Harry Hariharan

Cloacal swabs from 45 Grenada bank tree boas (Corallus grenadensis) were sampled during a 12‐month period (2011–2012) from the rain forests and scrublands of Grenada. Cloacal swabs were examined by enrichment and selective culture for the presence of Salmonella spp. In all, 16 (35.6%) of the snakes were positive for Salmonella, and six serovars of Salmonella were isolated. The most common serovar was Rubislaw (31.3%), the most frequent serovar recently isolated from green iguanas in Grenada, followed by serovar Braenderup (18.8%), and serovar IV:48:g,z51:‐ (formerly, S. Marina) (18.8%), also found in green iguanas in this country. The remaining three less frequent serovars were, IV:53:g,z51:‐, I:6,7:e,h:‐ and IIIb:38:i:z. Antimicrobial susceptibility tests conducted by a disc diffusion method against amoxicillin–clavulanic acid, ampicillin, cefotaxime, ciprofloxacin, enrofloxacin, gentamicin, imipenem, nalidixic acid, streptomycin, tetracycline and trimethoprim–sulfamethoxazole showed that drug resistance is minimal, with intermediate susceptibility, only to streptomycin. This is the first report of isolation and antimicrobial susceptibilities of Salmonella serovars from wild Grenadian tree boas.

Background and Aim: There is currently no published information on the prevalence and antimicrobial susceptibility patterns of commensal Escherichia coli in dogs of Grenada origin. Monitoring antimicrobial resistance helps in the empirical selection of antibiotics. This study determined the occurrence of E. coli including the O157:H7 serotype in feces of non-diarrheic dogs of Grenada origin and the antibiotic resistance pattern of the E. coli isolates. Materials and Methods: Fecal samples from 142 of the 144 (98.6%) dogs were culture positive for E. coli. Selection of up to three colonies from each of the 142 E. coli-positive samples yielded a total of 402 E. coli isolates, which were analyzed for the presence of non-sorbitol fermenting colonies, and O157-agglutination. Results: Of the 402 E. coli isolates, 30 (7.5%) were non-sorbitol fermenters. However, none of the 402 isolates gave a positive reaction (O157:H7) to the E. coli O157:H7 latex kit. Antimicrobial susceptibility tests against 12 antibiotics revealed low resistance rates to all the tested antibiotics except for tetracycline (Te) (23.4%), cephalothin (CF) (13.2%), and ampicillin (AM) (7.7%). Thirty-nine out of the 402 (9.7%), E. coli isolates were resistant to two or more antibiotics of different classes. Conclusion: This is the first report of isolation and antimicrobial susceptibilities of commensal E. coli from non-diarrheic dogs in Grenada. Some of the isolates (39/402 isolates, 9.7%) were resistant to multiple antibiotics. This study showed that presently, dogs in Grenada should not be considered a reservoir for the E. coli O157:H7 serotype and for multiple antibiotic-resistant E. coli strains. Among the 402 E. coli isolates, the resistance rate to drugs other than Te, CF, and AM was very low.

Aim: The purpose of this study was to estimate the prevalence of Salmonella species and to determine the antimicrobial susceptibility of isolates in brown rats (R. norvegicus) from two parishes (St. George and St David) of Grenada, West Indies. Study Design: Salmonella spp. was investigated in brown rats from Grenada, West Indies. Place and Duration of Study: Rats were trapped from two parishes: St David and St. George of Grenada, West Indies. Duration of study was from May to July 2017. Methodology: One hundred and seventy rats were trapped from 2 parishes (St. George and St David) of Grenada which have dense human population. The trapping was performed near the human dwellings. After necropsy, intestinal contents were collected and cultured for Salmonella bacteria using enrichment and selective culture techniques. Serotyping of Salmonella isolates was performed at the OIE Salmonella reference laboratory Guelph, Ontario, Canada. Antimicrobial susceptibility of the serovars was tested. Results: Fifteen rats (8.8%) were found positive for Salmonella spp. Five serovars of Salmonella were identified: S. javiana (36.8%); S. panama (26.3%); S. oranienburg and S. montevideo (15.7%) each; and L: Rough (5.2%). S. oranienburg has been isolated for the first time in Grenada. All serovars were found susceptible to 10 antimicrobial drugs; amoxycillin clavulanic acid, ampicillin, Choramphenicol, cephalothin, ciprofloxacin, ceftazidime, acefotaxime, imipenem, gentamycin and neomycin. Resistance of serovars to two antimicrobial drugs (tetracyclin and sulfamethoxazole-trimethaprim) was observed. Conclusion: All serovars identified in brown rats in Grenada are known pathogens causing serious disease in humans. Presence of Salmonella spp. in rats in a densely human populated area of Grenada may play a role in transmission of Salmonella to humans.

Non‐typhoidal salmonellosis remains an important public health problem worldwide. Dogs may harbourSalmonellain their intestines and can easily shedSalmonellain the environment with the possibility of transmission to humans. Thus, monitoring is essential to understand the role of dogs in zoonotic transmission. The objectives of this study were to determine the shedding ofSalmonellaby owned, apparently healthy dogs in Grenada, West Indies, to identify the serovars, and to examine their antimicrobial susceptibility profiles. Faecal samples collected during August to October, 2016 from 144 non‐diarrhoeic owned dogs were examined by enrichment and selective culture for the presence ofSalmonellaspp. Eight (5.6%) of the tested animals were culture positive, yielding 35Salmonellaisolates that belonged to six serovars ofSalmonella entericasubspeciesenterica. These were serovars Arechavaleta from two dogs, Arechavaleta and Montevideo from one dog, and Javiana, Rubislaw, Braenderup and Kiambu from one dog each. All these serovars have been reported as causes of human salmonellosis globally. Antimicrobial susceptibility tests on 35 isolates showed absence of resistance to the currently used drugs for cases of human salmonellosis, including ciprofloxacin and cefotaxime. One isolate (2.9%) was resistant to neomycin, two isolates (5.7%) showed intermediate susceptibility to neomycin, and another (2.9%) had intermediate susceptibility to tetracycline. This is the first report of isolation and antimicrobial susceptibilities of non‐typhoidalSalmonellaserovars from dogs in Grenada. This study shows that dogs in Grenada may be involved in the epidemiology of salmonellosis.

Aim: This study was carried out to assess the prevalence of Campylobacter spp. in free range chickens in Grenada, West Indies and to determine the antimicrobial susceptibility of isolates. Study Design: Cloacal swabs were collected from 315 free range chickens from randomly selected households from all six parishes of Grenada between June and July 2014. Cloacal swabs were cultured for Campylobacter in the Pathobiology Diagnostic Laboratory, School of Veterinary medicine, St. Georges University Grenada. Isolates were further tested through PCR for speciation. Methodology: Standard culture methods for isolation of Campylobacter spp were used. Isolates were characterized by conventional phenotypic tests and confirmed by PCR using species specific primers. The 16s rRNA gene for Campylobacter spp.; the map A gene for C. jejuni and the ceuE gene for C. coli were selected for PCR. Isolates were tested through E-test for their antimicrobial susceptibility using Ampicillin, Ciprofloxacin, Chloramphenicol, Erythromycin, Gentamicin, Metronidazole and Tetracycline. Results: A total of 158 isolates (50.2%) were obtained by culture. PCR on 93 isolates identified 33 isolates as C. jejuni, 6 as C. coli and 54 as mixed infection with C. jejuni and C. coli. None of the isolates was resistant to chloramphenicol and erythromycin; susceptibility to other antimicrobials varied among isolates. Multidrug resistance was high in C. coli (33.3%), followed by mixed infection isolates (22.2%) and C. jejuni (12.0%). Conclusion: Results of the study show that approximately 50% of backyard chickens in Grenada harbor Campylobacter spp. These backyard chickens pose a great risk for humans as hazard analysis critical control point (HACCP) is not observed during the slaughter and processing of these chickens.

Aim: The present study was conducted to evaluate the occurrence of bacterial respiratory pathogens, particularly members of the family Pasteurellaceae in healthy domestic goats in Grenada, and to determine the antimicrobial susceptibility of the predominant species.

Aim: To evaluate the prevalence of aerobic bacteria associated with the intestine and hepatopancreas of blue land crab and the susceptibility of the bacteria to a panel of antimicrobials that included some drugs used for the treatment of bacterial infections in the human and veterinary clinics in Grenada. Study Design: The tested crabs were collected during a three month period from November 2011 to February 2012 from six parishes of Grenada and analyzed in the bacteriology lab in the Pathobiology Department, School of Veterinary medicine, St. George’s University, Grenada, West Indies. Methodology: A total of 65 blue land crabs were examined for the presence of Gram-negative aerobic bacteria in their intestines and hepatopancreas by culture. The isolated bacterial species were tested against 12 antibiotics using the disc diffusion method. Results: Eighty-nine percent of crabs were culture positive. Klebsiella pneumoniae was the most common species (60%), followed by Citrobacter freundii (28%), Enterobacter cloacae (17%), Salmonella spp. (17%), and Escherichia coli (12%). Vibrio isolates included V. alginolyticus (8%), V. parahaemolyticus (5%), and V. fluvialis (3%). Antimicrobial susceptibility tests against 12 drugs showed susceptibility of all K. pneumoniae, C. freundii, Enterobacter cloacae, and Escherichia coli isolates to enrofloxacin, gentamicin, and imipenem. Resistance to ciprofloxacin, chloramphenicol, and trimethoprim-sulfamethoxazole was ≤ 7%. All K. pneumoniae isolates were resistant to ampicillin, and all C. freundii isolates were resistant to cephalothin. Resistance to tetracycline was highest (33%) in E. cloacae, and ≤ 13% in the other three major species. Susceptibility of Salmonella serotypes has been published, and no resistance was seen among any of the isolates. Conclusion: This study showed that the blue land crabs of Grenada, commonly used as food, can serve as reservoirs of potential human pathogens, and may carry bacteria resistant to antimicrobial drugs used for treatment in human medicine.

Invasive mammals can be important reservoirs for human pathogens. A recent study showed that 12% of mongooses carried Salmonella spp. in their large intestines. We investigated whether anthropogenic, environmental and climatic variables predicted Salmonella status in mongooses (Herpestes auropunctatus) in Grenada. Using multivariate logistic regression and contingency table analysis, we found that increased human density, decreased distance from roads, and low monthly precipitation were associated with increased probability of Salmonella carriage. Areas with higher human density likely support a higher abundance of mongooses because of greater food availability. These areas also are a likely source for infection to mongooses due to high densities of livestock and rodents shedding Salmonella. The higher probability of Salmonella carriage in mongooses during drier months and closer to roadsides is likely due to water drainage patterns and limited water availability. Although the overall prevalence of Salmonella in mongooses was moderate, the strong patterns of ecologic correlates, combined with the high density of mongooses throughout Grenada suggest that the small Indian mongoose could be a useful sentinel for Salmonella surveillance. Its affinity for human-associated habitats suggests that the small Indian mongoose is also a risk factor in the maintenance and possible spread of Salmonella species to humans and livestock in Grenada.

Over a 2-year period 66 cases of canine pyoderma in Grenada, West Indies, were examined by aerobic culture in order to ascertain the bacteria involved and their antimicrobial resistance patterns. Of the 116 total bacterial isolates obtained, the majority belonged to Gram-positive species, and the most common organism identified through biochemical and molecular methods wasStaphylococcus pseudintermedius. Additionally, identification of aStaphylococcus schleiferisubspeciescoagulansisolate was confirmed by molecular methods. All isolates of staphylococci were susceptible to beta-lactam drugs: amoxicillin-clavulanic acid, cefovecin, cefoxitin, cefpodoxime, and cephalothin. They were also susceptible to chloramphenicol and enrofloxacin. Resistance was highest to tetracycline. Methicillin resistance was not detected in any isolate ofS. pseudintermediusor inS. schleiferi. Among the Gram-negative bacteria, the most common species wasKlebsiella pneumoniae, followed byAcinetobacter baumannii/calcoaceticus. The only drug to which all Gram-negative isolates were susceptible was enrofloxacin. This report is the first to confirm the presence ofS. pseudintermediusandS. schleiferisubspeciescoagulans, in dogs with pyoderma in Grenada, and the susceptibility of staphylococcal isolates to the majority of beta-lactam drugs used in veterinary practice.

Rectal swabs from 155 sheep and 252 goats from Grenada were evaluated to determine the prevalence ofCampylobacterspp., antibiotic resistance, and multilocus sequence types. FifteenCampylobacterisolates were obtained (14C. jejuniand 1C. coli). The prevalence (3.7%) did not differ significantly between sheep (4.5%) and goats (3.2%). Among the seven antimicrobials tested, resistance was only detected for tetracycline (30.8%) and metronidazole (38.5%).Campylobacterisolates showed no significant difference between sheep and goats for type of antimicrobial resistance or percent of resistant isolates. Twelve of the isolates were successfully genotyped consisting of four recognized clonal complexes and three novel sequence types. Importantly, one isolate from one goat was identified as theC. jejunisequence type-8, a zoonotic and tetracycline-resistant clone reported to be a highly virulent clone associated with ovine abortion in the USA. Although most samples were from comingled sheep and goat production units, there were no shared sequence types between these two host species. None of the sequence types identified in this study have previously been reported in poultry in Grenada, suggesting sheep- and goat-specificCampylobacterclones in Grenada. This is the first report of genotyping ofCampylobacterisolates from sheep and goats in the Eastern Caribbean.