Antimicrobial susceptibility of clinical isolates of Pseudomonas aeruginosa from dogs in Grenada

A total of 44 isolates of Pseudomonas aeruginosa were recovered from various clinical conditions during the last 5 years from dogs in Grenada. The majority of isolates originated from otitis, and skin conditions including dermatitis, wounds, and abscesses. The isolates were tested for their susceptibility to 6 antibiotics using a standard disk diffusion test. Resistance was least to gentamicin (9.8%), followed by enrofloxacin (15.8%), and neomycin (41.8%). Resistance to tetracycline was 85.3%, and all isolates showed inherent resistance to amoxicillin-clavulanic acid and cephalothin.

Prevalence of Shigella serogroups and their antimicrobial resistance patterns in southern Trinidad.

The serogroup distribution and antimicrobial susceptibility patterns of Shigella isolates obtained from stool specimens of persons with acute diarrhoea in community-based studies from southern Trinidad during 1997-2006 were reviewed. Of the 5,187 stool specimens, 392 (8 per cent) were positive for Shigella organisms. From these 392 isolates, 88.8 per cent were recovered from children aged >0-10 year(s). Shigella sonnei was the most frequently-isolated serogroup (75 per cent), followed by S. flexneri (19 per cent), S. boydii (4.1 per cent), and S. dysenteriae (1.8 per cent). S. flexneri was the major isolate among the >20-30 years age-group. The most common drug resistance among all age-groups was to ampicillin. All strains of S. flexneri, S. boydii, and S. dysenteriae were fully susceptible to aztreonam, gentamicin, and ciprofloxacin. S. sonnei, the most common species isolated, showed resistance to all antibiotics tested. The data showed that, throughout the study period, the resistance to commonly-used drugs was relatively low. Since resistance to several drugs seems to be emerging, continuous monitoring of resistance patterns is mandatory for the appropriate selection of empiric antimicrobial drugs in the therapy of suspected cases of shigellosis.

Antibiotic susceptibility of clinical isolates of Staphylococcus intermedius and Staphylococcus aureus from dogs in Grenada.

Sixty-nine Staphylococcus intermedius isolates from various clinical conditions in dogs over a 3 year period were evaluated for in vitro susceptibility to 8 antibiotics using the disk diffusion method. The majority of the isolates originated from cases of pyoderma (30.4%), and otitis externa (29.0%). The least resistance was seen against cephalothin (1.6% of the 64 isolates, followed by chloramphenicol (3.9% of 26 isolates). Highest resistance was seen against ampicillin (34.4% of 32 isolates), followed by tertracycline (29.0% of 69 isolates). Resistance rates to other drugs were as follows: enrofloxacin 17.1%, gentamicin 7.3%, neomycin 6.1% and amoxicillin-clavulanic acid, 4.6%. Eleven isolates of S. aureus, showed no resistance to cephalothin. Overall the S. intermedius and S. aureus isolates were highly sensitive to cephalothin (98.7% susceptibility), suggesting that the first generation cephalosporins may be most useful drugs for treatment of Staphylococcus infection in dogs in Grenada.

Antibiotic susceptibility of clinical isolates of Staphylococcus intermedius and Staphylococcus aureus from dogs in Grenada.

Sixty-nine Staphylococcus intermedius isolates from various clinical conditions in dogs over a 3 year period were evaluated for in vitro susceptibility to 8 antibiotics using the disk diffusion method. The majority of the isolates originated from cases of pyoderma (30.4%), and otitis externa (29.0%). The least resistance was seen against cephalothin (1.6% of the 64 isolates, followed by chloramphenicol (3.9% of 26 isolates). Highest resistance was seen against ampicillin (34.4% of 32 isolates), followed by tertracycline (29.0% of 69 isolates). Resistance rates to other drugs were as follows: enrofloxacin 17.1%, gentamicin 7.3%, neomycin 6.1% and amoxicillin-clavulanic acid, 4.6%. Eleven isolates of S. aureus, showed no resistance to cephalothin. Overall the S. intermedius and S. aureus isolates were highly sensitive to cephalothin (98.7% susceptibility), suggesting that the first generation cephalosporins may be most useful drugs for treatment of Staphylococcus infection in dogs in Grenada.

Characterization of invasive isolates of S. pneumoniae, H. influenzae, and N. meningitidis in Latin America and the Caribbean: SIREVA II, 2000-2005

OBJECTIVES: To analyze the phenotypical characteristics and the susceptibility to antibiotics of the circulating strains of Streptococcus pneumoniae, Haemophilus influenzae, and Neisseria meningitidis circulating in Latin America and the Caribbean from 2000-2005. Potential coverage by conjugate vaccines was evaluated. METHODS: Conventional methods were used to study the distribution of the serotypes or serogroups of 17 303 strains of S. pneumoniae, 2 782 strains of H. influenzae, and 6 955 strains of N. meningitidis isolated from cases of pneumonia, meningitis, sepsis, bacteriemias, and other invasive processes. The antimicrobial susceptibilities of the study strains were evaluated. The isolates came from 453 sentinel surveillance sites in 19 countries in Latin America and four in the Caribbean, as part of the SIREVA II (Network Surveillance System for the Bacterial Agents Responsible for Pneumonia and Meningitis) project. RESULTS: S. pneumoniae serotype 14 was the most frequently isolated (21.1 percent), especially in children under 6 years of age (29.1 percent). The potential coverages by hepta-, nona-, deca-, and trideca-valent antipneumonia conjugate vaccines were 59.0 percent, 73.4 percent, 76.5 percent, and 85.9 percent, respectively. Of the isolates, 63.3 percent were sensitive to penicillin. H. influenzae serotype b was present in 72.2 percent of the isolations from children under 2 years of age, whereas 8.6 percent produced serotypes a, c, d, e, and f, and 19.2 percent could not be serotyped. The rate of H. influenzae beta-lactamase-producing strains isolated from children under 2 years of age was 16.3 percent. The most frequent N. meningitidis serogroups were B (69.0 percent) and C (25.7 percent); 65.8 percent and 99.2 percent of the strains were susceptible to penicillin and rifampicin, respectively. CONCLUSIONS: These results highlight the importance of comprehensive epidemiological surveillance of S. pneumoniae, H. influenzae and N. meningitidis in Latin America and the Caribbean. The great heterogeneity found in the distribution of S. pneumoniae serotypes among the countries studied could reduce immunization coverage. Conducting a specific analysis of each country to adjust the introduction of new conjugate vaccines and determine the best immunization plan is recommended

Antimicrobial drug resistance and genetic diversity of commensal Escherichia coli from caeca of chickens in Grenada.

The main goal of this study was to generate baseline data on resistance to 11 antimicrobial drugs of global importance among commensal Escherichia coli from healthy chicken in Grenada. For this purpose, a total of 183 commensal Escherichia coli isolates from 197 chickens (147 broilers and 50 layers) originating from 11 poultry farms in Grenada were studies using a standard disk diffusion method. The isolates were further studied for their haemolytic properties using sheep blood agar, and genotypes using the enterobacterial repetitive intergenic consensus sequence PCR (ERIC-PCR). Sixty-six isolates were positive for alpha haemolysis, and the remaining were non-haemolytic. There was no difference in antimicrobial susceptibility between haemolytic and non-haemolytic isolates. Resistance was highest against tetracycline (58.5%) followed by streptomycin (44.3%) and lowest to chloramphenicol (0.55%). Only three isolates (1.6%) showed resistance to fluoroquinolones. Resistance rates to tetracycline, streptomycin, and gentamicin were significantly lower among isolates from layers, compared with those from broilers. Multiple resistance to three or more classes of drugs was found in 10.4% of total isolates; the most common R-profile was Amp, Str, Tet. Twenty genotypes were identified among 24 randomly selected isolates that originated from 11 unrelated farms and 5 geographical locations. Isolates sharing similar genomic fingerprints by ERIC-PCR had different resistance profiles, whereas isolates with different genotypes shared similar profiles. In conclusion, this study showed the genetic diversity of chicken isolates from Grenada, and their significance and the epidemiological significance of ERIC-PCR genotypes among poultry isolates need further study.

Antimicrobial drug resistance and genetic diversity of commensal Escherichia coli from caeca of chickens in Grenada.

The main goal of this study was to generate baseline data on resistance to 11 antimicrobial drugs of global importance among commensal Escherichia coli from healthy chicken in Grenada. For this purpose, a total of 183 commensal Escherichia coli isolates from 197 chickens (147 broilers and 50 layers) originating from 11 poultry farms in Grenada were studies using a standard disk diffusion method. The isolates were further studied for their haemolytic properties using sheep blood agar, and genotypes using the enterobacterial repetitive intergenic consensus sequence PCR (ERIC-PCR). Sixty-six isolates were positive for alpha haemolysis, and the remaining were non-haemolytic. There was no difference in antimicrobial susceptibility between haemolytic and non-haemolytic isolates. Resistance was highest against tetracycline (58.5%) followed by streptomycin (44.3%) and lowest to chloramphenicol (0.55%). Only three isolates (1.6%) showed resistance to fluoroquinolones. Resistance rates to tetracycline, streptomycin, and gentamicin were significantly lower among isolates from layers, compared with those from broilers. Multiple resistance to three or more classes of drugs was found in 10.4% of total isolates; the most common R-profile was Amp, Str, Tet. Twenty genotypes were identified among 24 randomly selected isolates that originated from 11 unrelated farms and 5 geographical locations. Isolates sharing similar genomic fingerprints by ERIC-PCR had different resistance profiles, whereas isolates with different genotypes shared similar profiles. In conclusion, this study showed the genetic diversity of chicken isolates from Grenada, and their significance and the epidemiological significance of ERIC-PCR genotypes among poultry isolates need further study.

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

Caregivers' practices, knowledge and beliefs of antibiotics in paediatric upper respiratory tract infections in Trinidad and Tobago: a cross-sectional study

BACKGROUND: Antibiotic overuse and misuse for upper respiratory tract infections in children is widespread and fuelled by public attitudes and expectations. This study assessed knowledge, beliefs, and practices regarding antibiotic use for these paediatric infections among children's caregivers' in Trinidad and Tobago in the English speaking Caribbean. METHODS: In a cross-sectional observational study, by random survey children's adult caregivers gave a telephone interview from November 1998 to January 1999. On a pilot-tested evaluation instrument, respondents provided information about their knowledge and beliefs of antibiotics, and their use of these agents to treat recent episodes (< previous 30 days) of upper respiratory tract infections in children under their care. Caregivers were scored on an antibiotic knowledge test and divided based on their score. Differences between those with high and low scores were compared using the chi-square test. RESULTS: Of the 417 caregivers, 70% were female and between 18-40 years, 77% were educated to high school and beyond and 43% lived in urban areas. Two hundred and forty nine (60%) respondents scored high (>or12) on antibiotic knowledge and 149 (34%) had used antibiotics in the preceding year. More caregivers with a high knowledge score had private health insurance (33%), (p < 0.02), high school education (57%) (p < 0.002), and had used antibiotics in the preceding year (p < 0.008) and within the last 30 days (p < 0.05). Caregivers with high scores were less likely to demand antibiotics (p < 0.05) or keep them at home (p < 0.001), but more likely to self-treat with antibiotics (p < 0.001). Caregivers administered antibiotics in 241/288 (84%) self-assessed severe episodes of infection (p < 0.001) and in 59/126 (43%) cough and cold episodes without visiting a health clinic or private physician (p < 0.05). CONCLUSIONS: In Trinidad and Tobago, caregivers scoring low on antibiotic knowledge have erroneous beliefs and use antibiotics inappropriately. Children in their care receive antibiotics for upper respiratory tract infections without visiting a health clinic or a physician. Educational interventions in the community on the consequences of inappropriate antibiotic use in children are recommended. Our findings emphasise the need to address information, training, legislation and education at all levels of the drug delivery system towards discouraging self-medication with antibiotics in children.

Antimicrobial susceptibility survey of Pseudomonas aeruginosa strains isolated from clinical sources

A two-year prospective study of 554 Pseudomonas aeruginosa isolates was recovered from various clinical sources throughout Trinidad, and their resistance patterns to antipseudomonal antimicrobial agents were determined. Of the 554 P. aeruginosa isolates, 20.6% (114/554) were community isolates, 17.3% (96/554) from the intensive care unit (ICU), 10.1% (56/554) from the nursery, and the remaining 52% (288/554) were from other hospital inpatient services. Respiratory tract infections were the predominant source of P. aeruginosa isolates from the ICU--46.9% (45/96)--and nursery--21.4% (12/56), whereas wounds were the principal source of P. aeruginosa from the surgical services--77.0% (141/183). Community isolates of P. aeruginosa were predominantly from ear--100% (51/51)--and urinary tract infections--35.5%, (33/93). The overall prevalence of resistance was low for both hospital isolates (13.9%) and community isolates (3.8%). All community isolates were fully sensitive to four of the nine antimicrobials tested. Resistance rates among community strains ranged from 2.6% (ciprofloxacin and ceftazidime) to 12.3% for piperacillin. All isolates from hospital were fully sensitive to imipenem, but resistance rates for the other drugs ranged between 2.5% and 27.3%. The study showed that the overall resistance pattern of P. aeruginosa was relatively low. This is an encouraging observation but invites caution since resistance to the newly introduced drug, cefepime, has now emerged within the hospital environment and may present serious therapeutic problems within the near future. Policies governing the use of antimicrobials in many institutions are lacking. Such policies must be instituted in order to limit the spread of resistance and also to reduce the emergence of resistance to newly commissioned drugs within the country.

La resistencia a antimicrobianos en las Americas / Antimicrobial resistance in the Americas

The increase in the resistance to antimicrobials has become a serious public health concern. Responding jointly to this problem, the Pan American Health Organization and the Pan American Association of Infectious Diseases, supported by the Ministry of Health and Social Welfare of Venezuela, organized the Pan American Conference on Antimicrobial Resistance, which was held in Caraballeda, Venezuela, from 2 to 4 November 1998. In this work the principal recommendations coming out of that conference are summarized for each subject addressed there: educating health professionals on the appropriate use of antibiotics, developing a Pan American network to monitor resistance, quality control and ways to achieve laboratory results that are consistent and comparable, and the appropriate use of antibiotics, both in hospitals and in the community (AU)

The control of tuberculosis in the Caribbean

A survey of the Ministries of Health in the English-speaking Caribbean countries was conducted with the purpose of collecting information about current capacity in the prevention and control of tuberculosis. A response rate of 78.9 percent was achieved. The results of this survey indicate that tuberculosis control programmes in the English-speaking Caribbean are limited, and inadequately address issuse relating to multi-drug resistant disease and co-infection with human immunodeficiency virus (HIV). Limitations and implications of this survey are discussed. (AU)

Antibiotic resistance patterns of gram negative aerobic bacilli - a Caribbean collaborative study

The World Health Organization (WHO) has been taking active interest in the problem of antibiotic resistance and its impact on global health in developed and developing countries. A programme was initiated by CAREC to systematically study the antibiotic reistance pattern of bacteria in the Caribbean by a Standardised protocol to obtain information for the formulation of guidelines for appropriate use of antibiotics (AU)

Imported malaria in Trinidad and Togago, W. I. - 1968-1986

Malaria surveillance was conducted by the Insect Vector Control Division, Ministry of Health, to determine the number of imported cases of malaria which entered Trinidad and Tobago from 1968 to 1986. A total of 84 cases of imported malaria was detected; in 44 the agent as Plasmodium falciparum, in 25 P. vivax, in 11 P. malariae, in one P. ovale, and three are mixed. The monthly incidence of malaria showed that July and August acconunted for 41 percent of all imported malaria cases. Most malaria cases were diagnosed among male patients (74.3 percent) whereas the most significant age group contracting malaria was 20-29 years. Twenty-seven per cent of the persons contracting malaria were Trinidadians, while tourists, seamen and contract officers accounted for 21 percent. The African continent was responsible for 60 percent, India 25 percent and South America 12 percent of the imported malaria cases diagnosed and treated in Trinidad. Trinidadians of African and East Indian descent accounted for 78 percent of all imported malaria cases. Malaria resistance and relapse are discussed. The need to maintain port surveillance is emphasized.(AU)

Malaria resistance in Guyana, South America

Two imported cases of Chloroquine-, Fansidar-, and quinine-resistant Plasmodium falciparum malaria were diagnosed and treated in Trinidad, West Indies. The infections were cured by the administration of a multiple drug treatment regime of 45 mg Primaquine phosphate, 1.8 g sulphadoxine, 75 mg Pyrimethamine (Fansidar), and 650 mg quinine sulphate. Recrudescence has not occurred over the past 30 months. (AU)

Fansidar resistant falciparum import to Trinidad from Tanzania

A 27 year old Tanzanian female with an acute P. falciparum malaria infection failed to respond to the recommended radical Fansidar treatment. The case is classified as RII resistance because after 7 days, parasitemia clearance was not achieved. The infection was certainly acquired in Tanzania but diagnosed and treated in a non-malarious country. This is possibly the first case of Fansidar resistant falciparum malaria found sensitive to Chloroquine. Chloroquine and Primaquine effectively eradicated the P. falciparum malaria from the patient. (AU)

Some aspects of transmissible drug resistance in animals and their human contact - abstract

The use of antibiotics in animal feeds and in Veterinary Medicine is believed to select for antibiotic-resistant organisms in the normal gut flora of animals. Such resistant organisms may be passed to human contacts; if the resistance is due to transferable resistance factors, then the normal flora in the gut of human contact may become resistant to antibiotics. The purpose of this study was to ascertain the incidence of multiple drug resistance in the gut flora of pigs, to measure the transferability of these resistances to sensitive organisms and in addition to compare these patterns with those of the human contacts of the pigs. Faecal samples were collected from 110 pigs known to have received antibiotics (penicillin, di-hydrostreptomycin, oxytetracyline, chlortetracyline and sulfamethazine) and from 42 human contacts (handlers and relatives). Faecal samples were also collected from 72 pigs, not known to have received any antibiotics, and from 28 human contacts. Specimens were plated to MacConkey agar and antibiotic "Multodiscs" applied. Multiply-resistant organisms were mated with a multiply-sensitive recipient, in a modified version of the technique of Schroeder et al (1968). Antibiotic-resistant recombinants were recovered by plating the mixture on MacConkey agar containing nalidixic acid and/or streptomycin/tetracycline. Antibiograms were repeated on the recombinants. 96 percent of the faecal specimens from the test pigs yield multiply-resistant (more than 3 antibiotics) coliforms. This contrasted with 25 percent from the control pigs. 65 percent of the multiply-resistant organisms while none of the human contacts of the control pigs yielded multiply-resistant organisms. Only 27 percent of the multiply-resistant organisms in the human contact of the test pigs could tranfer some of all of the resistance factors. In all cases, resistance was greatest to streptomycin, tetracycline and sulfonamide. The high incidence of antibiotic resistance in the test pigs indicates the effect of prior antibiotic exposure on the selection of antibiotic resistant strains. The similarity of resistance patterns between the test pigs and their handlers suggests the transmission of organisms from pigs to man. The low frequency of transmissible drug resistance in the human contacts suggests instability of the transfer factor in the human intestine.(AU)