Yellow fever virus maintenance in Trinidad and its dispersal throughout the Americas

Trinidad, like many other American regions, experiences repeated epizootics of yellow fever virus (YFV). However, it is unclear whether these result from in situ evolution (enzootic maintenance) or regular reintroduction of YFV from the South American mainland. To discriminate between these hypotheses, we carried out a Bayesian phylogeographic analysis of over 100 prM/E gene sequences sampled from 8 South American countries. These included newly sequenced isolates from the recent 2008-2009 Trinidad epizootic and isolates derived from mainland countries within the last decade. The results indicate that the most recent common ancestor of the 2008-2009 epizootic existed in Trinidad 4.2 years prior to 2009 (95% highest probability density [HPD], 0.5 to 9.0 years). Our data also suggest a Trinidad origin for the progenitor of the 1995 Trinidad epizootic and support in situ evolution of YFV between the 1979 and 1988-1989 Trinidad epizootics. Using the same phylogeographic approach, we also inferred the historical spread of YFV in the Americas. The results suggest a Brazilian origin for YFV in the Americas and an overall dispersal rate of 182 km/year (95% HPD, 52 to 462 km/year), with Brazil as the major source population for surrounding countries. There is also strong statistical support for epidemiological links between four Brazilian regions and other countries. In contrast, while there were well-supported epidemiological links within Peru, the only statistically supported external link was a relatively weak link with neighboring Bolivia. Lastly, we performed a complete analysis of the genome of a newly sequenced Trinidad 2009 isolate, the first complete genome for a genotype I YFV isolate.

Seroprevalence and risk factors of Toxoplasma gondii infection among pregnant women in Trinidad and Tobago

OBJECTIVE: To determine the seroprevalence of toxoplasmosis and the frequency of risk factors for the disease in women attending antenatal clinics in hospitals and local health centers in Trinidad and Tobago. METHODS: From November 2002 - September 2003, 232 pregnant women at the antenatal clinics of two large hospitals were sampled during their first trimesters. From October 2003 – February 2005, 218 pregnant women at five health care centers were followed through three trimesters, wherever possible, and blood samples collected. Sera were screened for Toxoplasma gondii IgG and IgM immunoglobulins using an enzyme immunoassay. Data on demographics, as well as practices considered to be risk factors for toxoplasmosis, were obtained. RESULTS: Of the 232 women sampled at the two hospital clinics, 83 (35.8 percent) and 8 (3.4 percent) were seropositive for immunoglobulins of T. gondii IgG and IgM, respectively. Of the 218 women at the health centers, 76 (34.9 percent) had evidence of past infection (IgG), while 26 (11.9 percent) were seropositive for IgM immunoglobulin, suggesting new infections during pregnancy. Only having "3 or more" children was significantly associated with infection by T. gondii. CONCLUSION: In Trinidad and Tobago, the seroprevalence of past infection by T. gondii in pregnant women is relatively low (39.3 percent) for patients in both hospital and health center clinics. Consequently, there is an elevated risk of primary infection during pregnancy and the potential for congenital infection.

Selected bacterial recovery in Trinidadian children with chronic tonsillar disease.

Pharyngotonsillitis in children is widely treated with antibiotics. AIM: To examine tonsil surface and core microflora following elective adenotonsillectomy in children. METHODS: Tonsils of 102 Trinidadian children were prospectively examined for surface and core bacteriological culture and identification between 2005-2006. RESULTS: Tonsils (360) yielded 800 isolates of Streptococcus spp. (51.3 per cent), Staphylococcus spp. (42.3 per cent) and Gram-negative genera (6.4 per cent). Surface and core recovery of staphylococci and streptococci were similar (p>0.05). More (p<0.001) surfaces (82.2 per cent) than cores (63.3 per cent) grew Streptococcus spp.; a-haemolytic Streptococcus prevalence was higher (p<0.001) than B-haemolytic Streptococcus on surfaces (74.4 per cent vs. 18.6 per cent) than cores (58.9 per cent vs. 13.7 per cent). Surfaces and cores were not concordant for streptococci (p<0.0004) and   haemolytic Streptococcus (p<0.007). Surface and core B-haemolytic Streptococcus yield was higher (p<0.05) in 6-16 than 1-5 year olds (31 per cent and 23.8 per cent vs 12.5 per cent and 8 per cent). S. pyogenes surface and core prevalence was (84.6 per cent vs 70 per cent) and (50.0 per cent vs 25.0 per cent) in older and younger children respectively. Klebsiella spp. (6.6 per cent, 2.2 per cent), Proteus (4.4 per cent, 4.4 per cent) and Pseudomonas (4.4 per cent, 1.1 per cent) grew on surfaces and cores respectively.

Detection and phylogenetic analysis of group 1 coronaviruses in South American bats.

Bat coronaviruses (Bt-CoVs) are thought to be the precursors of severe acute respiratory syndrome coronavirus. We detected Bt-CoVs in 2 bat species from Trinidad. Phylogenetic analysis of the RNA-dependent RNA polymerase gene and helicase confirmed them as group 1 coronaviruses.

Pathogenicity and antibiotic sensitivity of Escherichia coli isolates from non-diarrhoeic dogs.

E. coli isolated from dogs in Trinidad were tested for their susceptibility to antimicrobial agents using the disk diffusion method. Antimicrobial agents and concentrations included cephalothin (KF, 30 ug), ampicillin (AMP, 10ug), kanamycin (K, 30 ìg), neomycin (N, 30 ug), gentamicin (CN, 10 ug), sulphamethoxazole/ trimethoprim (SXT, 23.25 ug/1.75 ug), nalidixic acid (NA, 30 ug) and norfloxacin (NOR, 10 ug). The overall prevalence of resistance to one or more antimicrobial agents for E. coli isolated from dogs was 47.9 per cent. The difference in prevalence across the various sources of the isolates from dogs was statistically significant (P<0.001; x2). Overall, resistance was highest to cephalothin (30.1 per cent). A total of 45 resistance patterns were observed from dogs from all sources and the predominant pattern was KF (25.6 per cent). It was concluded that the relatively high prevalence of resistance to antimicrobial agents amongst E. coli isolates from non-diarrhoeic dogs in Trinidad may pose zoonotic and therapeutic problems.

A cross-sectional study of isolates from sputum samples from bacterial pneumonia patients in Trinidad

We determined the frequency of Streptococcus pneumoniae, Haemophilus influenzae,Staphylococcus aureus, and Gram-negative enteric bacteria (GNEB) in pneumonia patients,determined the antibiograms of these pathogens, and investigated the relationship between pneumonia and selected risk factors. Sputum and demographic data were collected from 124pneumonia patients. Sputum was cultured for S. aureus, GNEB, H. influenzae and S. pneumoniae.The disc diffusion method was used to determine resistance to eight antimicrobial agents. Amongthe 124 sputum samples, eight (6.5%) were positive for S. aureus, 15 (12.1%) for GNEB, two(1.6%) for S. pneumoniae and one (0.8%) for H. influenzae. Hospitals, gender, ethnicity, comorbidities and symptoms did not significantly (p > 0.05; ö2) affect the prevalence of these bacteria.GNEB infection was most prevalent (47%) in patients over 70 years old. Gentamicin and levofloxacin were the most effective against these bacteria.

Microbial contamination of disinfectants and antiseptics in four major hospitals in Trinidad

OBJECTIVE: To assess the microbial contamination of disinfectants and antiseptics in major hospitals on the Caribbean island of Trinidad. METHODS: For this cross-sectional study, disinfectants and antiseptics were sampled from the pharmacy departments, the pediatric/neonatal wards, and the surgical wards of four hospitals. The samples were cultured for aerobic bacteria on nutrient agar using the surface plating method. The antibiotic sensitivity of bacterial isolates was determined by the disk diffusion method, using 14 antimicrobial agents. We studied a total of 180 disinfectant/antiseptic samples: 60 of chlorhexidine gluconate (Hibitane), 60 of chlorhexidine gluconate and cetrimonium bromide (Savlon), and 60 of methylated spirit. RESULTS: Of the 180 samples studied, 11 of them (6.1 percent) were contaminated by aerobic bacteria. All bacteria isolated were Pseudomonas spp. Of the 11 contaminated samples, 6 of them (54.5 percent) occurred at the pharmacy level while 5 (45.5 percent) were from diluted pre-use or in-use samples in the pediatric/neonatal wards or the surgical wards. Chlorhexidine gluconate and cetrimonium bromide accounted for 9 of the 11 contaminated disinfectants/antiseptics (81.8 percent), and chlorhexidine gluconate accounted for the remaining 2 (18.2 percent). Only two of the four hospitals had contaminated disinfectant/antiseptic samples. All 24 isolates of Pseudomonas spp. tested were resistant to one or more of the 14 antimicrobial agents tested, with the prevalence of resistance to ciprofloxacin, norfloxacin, tobramycin, and gentamicin being 58.3 percent, 50.0 percent, 45.8 percent, and 41.7 percent, respectively. CONCLUSIONS: Our results show that contaminated disinfectants/antiseptics pose a health risk to patients, particularly in the pediatric and surgical wards. The high prevalence of resistance to antimicrobial agents exhibited by the Pseudomonas spp. that were isolated is of special therapeutic concern

Epidemiology of human leptospirosis in Trinidad and Tobago, 1996-2007: a retrospective study.

A retrospective study to describe the epidemiology of human leptospirosis in Trinidad and Tobago during 1996–2007 was conducted. All confirmed cases of leptospirosis was analyzed according to age, sex, seasonality and geographic distribution. A total of 278 cases were recorded, with an average annual incidence rate of 1.84 per 100,000 population. Seventy-five percent of the cases occurred during the wet season, with the highest number of cases recorded in November. A positive correlation was found between number of cases and rainfall. Males constituted 80% of all cases, and the overall male:female ratio was 4.6:1. The total case fatality rate was 5.8 per cent, with deaths among males four times more common than in females. Clinical leptospirosis was greatest in the 10–19 age group and lowest in the 0–9 age group. The total prevalence was 22 per 100,000 population, with the highest prevalence 41 per 100,000 recorded in the regional corporation of Sangre Grande and the lowest (6 per 100,000) in the city of Port of Spain. The lack of important information and active surveillance showed that the level of awareness of the disease is low in the country. The disease is still under-reported, and is considered to be of significant public health importance.

Antibiotic-resistance patterns of bacterical pathogens isolated from ornamental fish in Trinidad and Tobago

Ornamental fish farming forms an important part of the local aquaculture industry in Trinidad and Tobago, and the number of farms has been increasing annually. This study was designed to ascertain the prevalence of bacterial pathogens from fish and pond water, and determine the resistance of the bacteria to commonly used antimicrobial agents. A total of 1204 bacterial isolates were recovered: from 575 fish slurry and 111 water samples from 17 aquaculture farms. Isolates from fish were identified as belonging to 19, and those from water samples were grouped in 18 genera. The predominant genera isolated were (in descending order) Aeromonas spp., Pseudomonas spp., Plesiomonas spp., Chromobacterium spp., Enterobacter spp. and Serratia spp. Screening against 8 antimicrobial agents showed that 95.1 percent (774 of 814) of isolates from fish slurry, and 98.4 percent (254 to 258) of isolates from pond water were resistant to one or more antimicrobial agents ( P> 0.05, X2). The highest resistance (55-94 percent) were to ampicillin, oxytetracycline and erythromycin, but relatively lower resistance (4-14 percent) occurred to gentamycin and norfloxacin (P< 0.05; X2). It was concluded that the high prevalence of bacterial pathogens in ornamental fish coupled with their high levels of resistance to antimicrobial agents may pose therapeutic problems as well as health risks to farmers, workers and fish hobbyists

Frequency and characteristics of selected enteropathogens in fecal and rectal specimens from childhood diarrhea in Trinidad, 1998-2000

Objective. To determine the prevalence and characteristics of selected enteric pathogens in diarrheic children in six counties of Trinidad. Methods. This cross-sectional study was conducted from April 1998 through March 2000, using standard methods, to detect Salmonella spp., Shigela spp., enteropathogenic Escherichia coli (EPEC), Campylobacter spp., Yersinia spp., Cryptosporidium parvum, and parasite ova. The antibiograms of the enteropathogens were determined using disk diffusion method.Results. A total of 236 samples; 86 samples originated directly from 17 health centers in two counties (St. George East and St. George West), while 150 samples were obtained from Trinidad Public Health Laboratory, having been submitted by private practitioners and personel from six counties in Trinidad. Of the 236 samples, 33 (14.0 percent) were positive for Shigella, 4 (1.7 percent) for Salmonella, and 1 (0.4 percent) was positive for hook worm ova. All the samples were negative for Cryptosporidium parvum and Yersinia spp. With the 86 samples collected directly from the health centers, in St. George East County the frequency of Shigella was 20.0 percent (12 of 60), compared with 26.9 percent (7 of 26) for samples from St. George West County, but the difference was not statistically significant (P> 0.05 with the chi-square test). For the 150 samples from the six counties that had been submitted directly to the Trinidad Public Health Laboratory, 14 of them (9.3 percent) were positive for Shigella, a figure statistically significantly lower than that found with the samples sampled directly from the health centers (P< 0.05 with the chi-square test). Sh. sonnei was the predominant serotype detected, accounting for 28 of the 33 Shigella isolates (84.8 percent) recovered from the 236 samples. Overall, the frequency of detection of enteropathogens had no seasonal pattern nor relationship to the county of origin. Of the 37 isolates of Salmonella and Shigella tested for antimicrobial sensitivity, all of them were sensitive to ciprofloxacin, gentamicin, and cefotaxime. In terms of resistance, 3 of the 37 isolates (8.1 percent) exhibited resistance to ampicillin, 1 (2.7 percent) to chloramphenicol, and 1 (2.7 percent) to sulfamethoxazole/ trimethoprim. Conclusions. Of the enteropathogens for which assays were done, Shigella sonnei was the most prevalent, and it has the highest probability of being an important etiological agent of childhood diarrhea in Trinidad (AU)

Microbial quality of "doubles" sold in Trinidad

A cross-sectional study was conducted to determine the prevalence and characteristics of Escherichia coli, Staphylococcus aureus, Bacillus spp. and Salmonella spp. in "bara", "channa", condiments/spices and ready-to-eat "doubles" sold by vendors in the St. George and Caroni counties of Trinidad. Of 196 samples of each of "bara", "channa", condiments/spices and ready-to-eat "doubles" examined, E. coli was detected in 0 (0.0 per cent), 14 (7.1 per cent), 96 (49.0 per cent) and 67 (34.2 per cent), respectively; Staphylococci were isolated from 104 (53.1 per cent), 71 (36.2 per cent), 129 (65.8 per cent) and 123 (62.8 per cent) samples, respectively; and Bacillus spp. were recovered from 22 (11.2 per cent), 85 (43.4 per cent), 100 (51.0 per cent) and 88 (44.9 per cent) samples, respectively. Salmonella spp. were not isolated from any sample. Of the 177 isolates of E. coli recovered from all sources, 9 (5.1 per cent), 7 (4.0 per cent) and 47 (26.6 per cent) were mucoid, haemolytic and non-sorbitol fermenters (NSF), respectively, but none agglutinated with O157 antiserum. Of 427 staphylococcal isolates, 130 (30.4 per cent) were confirmed as S. aureus of which 20 (15.4 per cent) were haemolytic and 84 (64.6 per cent) pigmented, while 17 (20.7 per cent) of 82 strains of S. aureus tested produced enterotoxins. Ready-to-eat "doubles", a popular food in Trinidad, therefore pose a potential health risk to consumers due to the high level of contamination with bacteria.

Absence of Escherichia coli 0157 in a survey of wildlife from Trinidad and Tobago

Fecal, cloacal, or rectal swabs of free-ranging and captive mammalian and avian wildlife in Trinidad and Tobago were cultured for non-sorbitol fermenting Escherichia coli and tested for 0157: H7 strains. Ability of E. coli strains to produce hemolysin and mucoid colonies also was investigated. Of 271 free-ranging mammals tested, 158 (58 percent) yielded E. coli; only one (< 1 percent) bacterial isolate was a non-sorbitol fermenter which was not agglutinated by 0157 antiserum. All isolates were negative for hemolysin production and mucoid colonial growth. Two hundred and sixty-three (90 percent) of 293 free-flying birds were positive for E. coli and all isolates were sorbitol fermenters and negative for production of hemolysin and mucoid growth. Of 175 captive wild animals from individual backyard farms and a government demonstration farm, 145 (83 percent) yielded E. coli with four (2 percent) non-sorbitol fermenters; all were negative for 0157 strains, hemolysin production, and mucoid colonial growth. Of 373 animals in a zoo, 250 (67 percent) were positive for E. coli with only two (0.5 percent) non-sorbitol fermenters. All strains were non-hemolytic and non-mucoid farms. It appears that free-ranging and captive avian and mammalian wildlife are not important reservoirs of 0157: H7 stains of E. coli in Trinidad and Tobago.(AU)

Microbiological analysis of "black pudding", a Trinidadian delicacy and health risk to consumers

The prevalence of Salmonella, Escherichia coli and Staphylococcus aureus in black pudding which originated from local vendors and supermarket in Trinidad were determined. The enterotoxigenicity of S. aureus strains and occurrence of 0157:H7 strains among E. coli isolates were also investigated. For the 100 black puddings each sampled from supermarkets and vendors, the mean total aerobic plate count (TAPC) per g was 1.8 x 10 (7) the mean total aerobic plate count (TAPC) per g was 1.8 x 10 (7) +/- 1.5 x 10 (7) and 1.5 x 10(8) +/- 2.3 x 10 (8), respectively. E. coli was isolated from 56 (56.0 percent) black pudding samples from supermarkets with a mean count per g of 9.2 x 10 (6) +/- 7.9 x 10 (6) compared to the prevalence of 79 percent (79 nof 100) and mean count per g of 3.2 x 10 (7) +/- 4.7 x 10 (7) for samples from local vendors. The differences between the prevalences was statistically significant (P < or = 0.0001; chi 2). Only 1 (2.2 percent) of 45 strains of E. coli from supermarket-purchased pudding tested, was an 0157:H7 strain compared to 9 (13.3 percent) of 66 strains of E. Coli from vendor-sold black puding. The difference was not statistically significant (P) or = 0.05; chi 2). Five (5.0 percent) of 100 black pudding samples from supermarkets utyielded Salmonella. wih S. ohio being the predominant serotype. For vendor-sold black pudding, however, 11 (11.0 percent) samples were positive for Salmonella with a new serotype, S. unmamed (4, 12:d-_ being responsible for 50 percent (6 of 12) of isolates from this source. Forty samples each of black pudding from supermarkets and vendors were all (100.0 percent) positive for S. aureus with mean counts per g being 3.1 x 10 (5) +/- 8.8 x 10(5) and 3.3 x 10 (6) +/- 7.7 x 10 (6), respectively. Overall, 27 (33.8 percent) of 80 strains of S. aureus tested were enterotoxigenic producing staphylococcal enterotoxins A(SEA), SEB, SEC, SED or a combination. It was concluded that black pudding poses a high risk to consumers based on the prevalence, microbial load and toxigenicity of the pathogens detected. (AU)

Longitudinal study on the susceptibility to bacteriophages of Staphylococcus aureus strains isolated from dairy farms in Trinidad

A 6-month longitudinal study was conducted on 30 dairy cows in early lactation and their human handlers on six farms across Trinidad. Weekly samples of bulk milk, composite milk and anterior nares and hand swabs from human handlers were collected and cultured for Staphylococcus aureus on Baird-Parker agar (BPA). The susceptibility of S. aureus strains to bacteriophages and the relatedness of strains isolated over the study period were determined. Sixty-three (51.2 percent) of 123 strains of S. aureus from bulk milk were typable compared with 111 (57.3 percent) of 194 and 82 (61.7 percent) of 133 strains isolated from composite milk and human handlers, respectively. The differences were not statistically significant (P> 0.05; chi 2). Bovine phage 42D lysed 3.3 percent (4 of 123), 16.5 percent (32 of 194) and 12.0 percent (16 of 133) of S. aureus strains isolated from bulk milk, composite milk and human handlers, respectively. The differences were statistically significant (P< 0.001; chi 2). Amongst bulk milk isolates of S. aureus, 35 (31.8 percent) of 110 exhibited relatedness in 11 groups based on their phage patterns and groups. The mean maximum interval between the first and last detection of related S. aureus strains in a group was 11.5 +/- 7.3 weeks. Amongst composite milk strains of S. aureus, 23 (46.0 percent) of 50, 25 (62.5 percent) of 40 and 22 (53.7 percent) of 41 exhibited relatedness on farms IB 2, IB 27 and IC 23, respectively, but the differences were not statistically significant (P> 0.05; chi 2). On farm IB 2, five groups of related strains of S. aureus were detected with a mean maximum interval of detection of 18.2 +/- 8.5 weeks compared to farm IB 27 where five groups of related strains were also observed but with an interval of 13.8 +/- 8.2 weeks. On farm IC 23, a total of seven groups of related S. aureus strains detected with a mean interval of 8.0 +/-5.5 weeks. For human strains of S. aureus from farm IB 2, nine (56.3 percent) of 16 strains isolated from anterior nares exhibited relatedness in three groups with a mean maximum interval of 13.3 +/- 4.7 weeks compared to four (25.0 percent) of 16 hand swab isolates which exhibited relatedness in two groups with a mean maximum interval of detection of 20.5 +/- 2.1 weeks compared to hand swab isolates, with six (50.0 percent) of 12 showing relatedness in two groups and a mean interval of 10.5 +/- 2.1 weeks. (AU)

Seroprevalences of brucellosis, Q-fever and toxoplasmosis in slaughter livestock in Trinidad

Serum samples obtained from livestock (cattle, chicken, pigs, sheep, goats and water buffaloes) slaughtered at various slaughter houses in Trinidad

Prevalence and characteristics of Staphylococcus aureus strains isolated from bulk and composite milk and cattle handlers

The prevalence and characteristics of Staphylococcus aureus strains isolated from bulk and composite milk and from cattle handlers on dairy farms in Trinidad were determined. S. aureus strains isolated from all 175 bulk milk samples tested (100 percent) while 280 of 287 composite milk samples (97.6 percent) yielded S. aureus. The mean counts of S. aureus in bulk milk ranged from 5.9 x 10(3) to 1.2 x 10(5) CFU/ml compard with mean S. aureus counts in composited milk which ranged from 2.4 x 10(3) to 3.0 x 10(4) CFU/ml. Of the 105 strains of S. aureus from bulk milk tested, 45 (42.9 percent) were enterotoxigenic elaborating staphylococcal enterotoxin A (SEA), SEB, SEC, SED, or a combination compared to 69 of 146 strains (47.3 percent) recovered from composite milk which were enterotoxigenic but the difference was not statistically significant (P > = 0.05; chi 2). Twenty-two of 42 bulk milk samples containing enterotoxigenic S. auerus (52.4 percent) had counts of the organism which exceeded 10(4) CFU/ml. For S. aureus strains isolated from cattle handlers, 66 of 146 (45.2 percent) were enterotoxigenic. Prevalence of resistance to nine antimicrobial agents tested was 18.7 percent and 12.9 percent among bulk milk and composite milk isolates, respectively, compared to 49.3 percent and 69.5 percent among isolates from human anterior nares and hand swabs, respectively. Resistance to ampicillin and penicillin was highest among both milk (12.2 percent) and human (53.6 percent) isolates of S. aureus, and the difference was statistically significant (P < or = 0.001); chi 2). It was concluded that bulk milk containing relatively high counts of enterotoxigenic S. aureus may constitute a health hazard to consumers(AU)

Prevalence and characteristics of Staphylococcus aureus strains isolated from bulk and composite milk cattle handlers

The prevalence and characteristics of Staphylococcus aureus strains isolated from bulk and composite milk and from cattle handlers on dairy farm all 175 bulk milk samples tested (100 percent) while 280 of 287 composite milk samples (97.6 percent) yielded S. aureus. The mean counts of S. aureus in bulk milk ranged from 5.9 x 10(3) to 1.2 x 10(5) CFU/ml compared with mean S. aureus counts in composite mild which ranged from 2.4 x 10(3) to 3.0 x 10(4) CFU/ml. Of the 105 strains of S. aureus from bulk milk tested, 45 (42.9 percent) were enterotoxigenic elaborating staphylococcal enterotoxin A (SEA), SEB, SEC, SED, or a combination compared to 69 of 146 stains (47.3 percent) recovered from composite milk which were enterotoxigenic, but the difference was not statistically significant (P > 0.05; chi 2). Twenty-two of 42 bulk milk samples containing enterotoxigenic S. aureus (52.4 percent) had counts of the organism which exceeded 10(4) CFU/ml. For S. aureus strains isolated from cattle handlers, 66 of 146 (45.2 percent) were enterotoxigenic. Prevalence of resistance to nine antimicrobial agents tested was 18.7 percent and 12.9 percent among bulk milk and composite milk isolates, respectively, compared to 49.3 percent and 69.5 percent among isolates from human anterior nares and hand swabs, respectively. Resistance to ampicillin and penicillin was highest among both milk (12.2 percent) and human (53.6 percent) isolates of S. aureus, and the difference was stastically significant (P < or in 0.001; chi 2). It was concluded that bulk milk containing relatively high counts of enterotoxigenic S. aureus may constitute a health hazard to consumers(AU)

Some bacterial enteropathogens in wildlife and racing pigeons from Trinidad

Fecal and cloacal swabs or feces of wild mammalian, avian and reptilian species, either farmed or free-ranging, and of racing pigeons (Columba livia) kept in lofts were cultured for Salmonella spp., Campylobacter spp., and Yersinia spp. Of 291 free-ranging mammals tested 6 (2 percent) and 1 (< 1 percent) and 1 (< 1 percent) yielded positive culture of Salmonella spp. and Campylobacter spp., respectively. Salmonella newport was the predominant serotype isolated and the opossum (Didelphis marsupialis insularis) had the significantly highest prevalence (29 percent) of Salmonella spp. infection compared to other species such as deer (Mazama americana trinitatis), lappe (Agouti paca), tattoo (Dasypus novemcinctus), agouti (Dasyprocta leporina), and wild hog (Tayassu tajacu). Among 14 species of farmed wildlife studied, 13 (7 percent) and 10 (5 percent) of 184 fecal or cloacal samples tested were positive for Salmonella spp. and Campylobacter spp., respectively. Salmonella javians accounted for 50 percent of the Salmonella spp. isolates and C. jejuni represented 90 percent of the Campylobacter spp. cultured. Only 1 (1 percent) of 124 cloacal swabs of free-flying avian species yielded Salmonella spp. compared to 21 (17 percent) samples positive for Campylobacter spp. Of 171 racing pigeons which originated from 8 fanciers, 8 (5 percent) yielded Salmonella spp. all of which were serotype typhimurium while only 1 (1 percent) were positive for Campylobacter spp. Seven (88 percent) of 8 Salmonella spp. isolates were recovered from one fancier. Yersina spp. was not cultured from any of the above samples. Although the prevalences of Salmonella spp. and Campylobacter spp. in wildlife in Trinidad are low, the practice of wildlife farming and the increased consumption of meat from wildlife may increase the health risk to human consumers(AU)

Campylobacter infections in calves, piglets, lambs and kids in Trinidad

Faeces or rectal swabs from 689 diarrhoeic and non-diarrhoeic animals were cultured for thermophilic campylobacters and their antibiograms were determined. Three hundred and fifteen (45.7 percent) samples were positive for Campylobacter. Piglets had the highest prevalence, 79.3 percent (233/294) and lambs, the lowest with 17.9 percent (15/84) being positive. The difference was statistically significant (P < or = 0.01; chi 2). In calves, 20.5 (60/293) and in kids 38.9 percent (7/18) were positive for campylobacters. The prevalence of infection was not significantly (P > or = 0.05; chi 2) different between diarrhoeic (46.1 percent) and non-diarrhoeic (45.1 percent) animals nor between male (47.5 percent) and female (43.8 percent). The frequency of isolation of campylobacters harvested from semi-intensively managed animals (75.4 percent) was, however, significantly higher (P < or = 0.001; chi 2) than from intensively or extensively managed animals. Overall, C. coli strains (32.8 percent) were more frequently isolated than C. jejuni strains (12.9 percent) and the difference was significant (P < or = 0.001; chi 2). Biotype I accounted for 67.3 percent (152/226) of C. coli and 64.0 percent (57/89) of C. jejuni strains isolated. A total of 245 (77.8 percent) strains of Campylobacter exhibited resistance to one or more antibiotics and was highest to streptomycin (76.5 percent), kanamycin (28.6 percent) and neomycin (26.7 percent). It was concluded that Campylobacter infections were widespread in livestock in Trinidad, particularly C. coli in piglets. (AU)

Microbial contamination of disinfectants and antiseptics in four major hospitals in Trinidad

Objective. To assess the microbial contamination of disinfectants and antiseptics in major hospitals on the Caribbean island of Trinidad. Methods. For this cross-sectional study, disinfectants and antiseptics were sampled from the pharmacy departments, the pediatric/neonatal wards, and the surgical wards of four hospitals. The samples were cultured for aerobic bacteria on nutrient agar using the surface plating method. The antibiotic sensitivity of bacterial isolates was determined by the disk diffusion method, using 14 antimicrobial agents. We studied a total of 180 samples: 60 of chlorhexidine gluconate (Habitane), 60 of chlorhexidine gluconate and cetrimonium bromide (Savlon), and 60 of methylated spirit. Results. Of the 180 samples studied, 11 of them (6.1 percent) were contaminated by aerobic bacteria. All bacteria isolated were Pseudomonas spp. Of the 11 contaminated samples, 6 of them (54.5 percent) occurred at the pharmacy level while 5 (45.5 percent) were from diluted pre-use or in-use samples in the pediatric/neonatal wards or the surgical wards. Chlorhexidine gluconate and cetrimonium bromide accounted for 9 of the 11 contaminated disinfectants/antiseptics (81.8 percent), and chlorhexidine gluconate accounted for the remaining 2 (18.2 percent). Only two of the four hospitals had contaminated disinfectant/antiseptic samples. All 24 isolates of Pseudomonas spp. tested were resistant to one or more of the 14 antimicrobial agents tested, with the prevalence of resistance to ciprofloxacin, norfloxacin, tobramycin, and gentamicin being 58.3 percent, 50.0 percent, 45.8 percent, and 41.7 respectively. Conclusions. Our results show that contaminated disinfectants/antiseptics pose a health risk to patients, particularly in the pediatric and surgical wards. The high prevalence of resistance to antimicrobial agents exhibited by the Pseudomonas spp. that were isolated is of special theraputic concern (AU)