Bacterial reservoirs in a health care environment: case of the Douala general Hospital, Cameroon

Background:Health care acquired infections are a major cause of morbidity and mortality in hospitals. There is very little documentation of this important problem in our resource limited setting. The aim of our study was to identify bacterial reservoirs and microorganisms with the potential of nosocomial infections in our health care environment Methods:Bacteriological samples from the air; surfaces; equipment; personnel and patients from six units of the Douala General Hospital; Cameroon were collected for culture according to standardised collection; culture and germs identification techniques. of all collected samples were contaminated with pathogenic bacteria. These included 83.3 of air samples and 100; 54.1and 48.7of specimens respectively. The same bacteria found on the hands of nursing personnel were same as on both surfaces and equipment. The intensive care and neonatal units were the most contaminated with 100 positive cultures. The sterilization unit was bacteria free

Prevalence, quantification and antimicrobial resistance of Campylobacter spp. on chicken neck-skins at points of slaughter in 5 major cities located on 4 continents.

Quantitative data on Campylobacter contamination of food are lacking, notably in developing countries. We assessed Campylobacter contamination of chicken neck-skins at points of slaughter in 5 major cities in Africa (Dakar in Senegal, Yaounde in Cameroon), Oceania (Noumea in New Caledonia), the Indian Ocean (Antananarivo in Madagascar) and Asia (Ho Chi Minh City (HCMC) in Vietnam. One hundred and fifty slaughtered chickens were collected in each of the 5 major cities from semi-industrial abattoirs or markets (direct slaughter by the seller), and 65.5% (491/750) were found to be Campylobacter-positive. Two cities, Yaounde and Noumea, demonstrated high prevalence Campylobacter detection rates (92.7% and 96.7% respectively) in contrast with HCMC (15.3%). Four species were identified among 633 isolates, namely C. jejuni (48.3%), C. coli (37.3%), C. lari (11.7%) and C. upsaliensis (1%). HCMC was the only city with C. lari isolation as was Antananarivo for C. upsaliensis. C. coli was highly prevalent only in Yaounde (69.5%). Among the 491 samples positive in Campylobacter detection, 329 were also positive with the enumeration method. The number of Campylobacter colony-forming units (CFU) per gram of neck-skin in samples positive in enumeration was high (mean of the log(10): 3.2 log(10) CFU/g, arithmetic mean: 7900CFU/g). All the cities showed close enumeration means except HCMC with a 1.81 log(10) CFU/g mean for positive samples. Semi-industrial abattoir was linked to a significant lower count of Campylobacter contamination than direct slaughter by the seller (p=0.006). On 546 isolates (546/633, 86.3%) tested for antibiotic susceptibility, resistance to erythromycin, ampicillin and ciprofloxacin was observed for respectively 11%, 19% and 50%. HCMC was the city where antibiotic resistant rates were the highest (95%, p=0.014). Considering the 329 positive chickens in Campylobacter enumeration, the mean number of resistant isolates to at least 2 different antibiotic families (19.8%), may be estimated ca. 1500CFU/g; the corresponding mean of the log(10) would be 2.5 log(10)CFU/g. As chickens are sold at slaughter and brought directly at home to be cooked, these data suggest a high probability of cross-contamination. A substantial proportion of isolates are drug-resistant, which could lead to potential public health issues. Health authorities should consider measures to reduce Campylobacter contamination of chicken during farming and at slaughter, and to provide appropriate food hygiene education. Further studies are needed in particular to investigate food-handling practices in domestic kitchens.

Multiple contaminations of chickens with Campylobacter, Escherichia coli and Salmonella in Yaounde (Cameroon).

INTRODUCTION: Food-borne diseases associated with Campylobacter, Escherichia coli, and Salmonella are mainly caused by the consumption of raw or undercooked poultry meat. The objective of this study was to evaluate the prevalence of Campylobacter, Escherichia coli, and Salmonella in chickens. METHODOLOGY: One hundred and fifty chickens collected from eight retail markets in Yaounde were examined for the presence of Campylobacter, Escherichia coli, and Salmonella using standard bacteriological procedures. RESULTS: Of the 150 chickens collected, 135 (90%) were contaminated with Campylobacter (68.9% C. coli and 31.1% C. jejuni). All the chickens were positive for E. coli. Among the 150 isolates, 17 (11.3%) were enteropathogenic E. coli (EPEC). Additionally, 103 Salmonella strains were recovered from 90 chickens. Salmonella Enteritidis (45.6%) and Salmonella Hadar (28.1%) were the most frequent serotypes. Multiple contamination was found in 142 chickens (94.6%), of which 83 (55.3%) were concurrently contaminated with Campylobacter, Escherichia coli, and Salmonella. CONCLUSION: These results show that chickens in Cameroon are highly contaminated with Campylobacter, Escherichia coli, and Salmonella. The multiple contaminations of chickens is a potential risk of infection for consumers and highlights the necessity of public awareness for food safety.

Prevalence and antimicrobial resistance of Salmonella serotypes in chickens from retail markets in Yaounde (Cameroon).

From February 2006 to January 2007, 150 chickens were collected from eight retail markets in Yaounde, and 90 (60%) tested positive for Salmonella. Seventy-nine chickens were contaminated with only one Salmonella serotype, 10 with two different serotypes, and 1 with four serotypes. The most prevalent serotypes were Enteritidis (47 strains) and Hadar (29 strains). The isolates were tested for their susceptibilities to amoxicillin, amoxicillin/clavulanic acid, cefoxitin, cefotaxime, gentamicin, streptomycin, tetracycline, chloramphenicol, sulfonamides, nalidixic acid, ciprofloxacin, and trimethoprim/sulfamethazole by disk diffusion assay. Minimum inhibitory concentrations of ampicillin, streptomycin, tetracycline, sulfonamides, and nalidixic acid were determined for the resistant strains by agar dilution method. Eleven isolates (10.7%) of the 103 tested were susceptible to all antimicrobials. Resistance was most observed to tetracycline (84.5%), streptomycin (44.7%), and nalidixic acid (34%). Forty-one isolates (39.8%) were multidrug resistant (resistant to three or more antimicrobials from different classes), of which 68.3% were Hadar and 21.9% Enteritidis. The most frequent resistant pattern in Hadar was streptomycin-tetracycline-nalidixic acid. These results highlight once more the need for surveillance of Salmonella contamination in poultry.

Antimicrobial resistance and molecular characterization of Vibrio cholerae O1 during the 2004 and 2005 outbreak of cholera in Cameroon.

There was an outbreak of cholera in Cameroon during 2004 and 2005; the epidemic began in Douala in January 2004 and spread throughout the south of the country. The World Health Organization (WHO) reported 8005 cases in 2004 and 2847 cases in 2005. Five hundred eighty-nine stool samples were received in the Pasteur Centre of Cameroon and 352 were microbiologically confirmed to be positive for Vibrio cholerae O1. Isolated strains were tested for their antimicrobial susceptibilities. All the strains were multidrug resistant and predominantly showed a common resistance pattern at the beginning of the outbreak. Tetracycline, recommended by the WHO for treating cholera in adults, was effective against all the strains tested. Cotrimoxazole (trimethoprim/sulfamethoxazole), previously a first-line treatment in children, was ineffective in vitro for all the clinical isolates and was quickly replaced by amoxicillin. Ampicillin resistance emerged at the end of 2004 and was the leading resistance pattern observed in the second half of 2005. This therefore represented the second major resistance pattern. These two major resistance profiles were not associated with patient characteristics (sex and age) or to the geographic origin of strains. However, there was a highly significant relationship between resistance patterns and the year of isolation (p < 0.001). The strains possessed genes ctxA and ctxB encoding the two cholera toxin subunits and were very closely related, irrespective of their antimicrobial resistance patterns. They were not differentiated by molecular typing methods and gave similar ribotyping and pulsed-field gel electrophoresis patterns.

An acute foodborne outbreak due to Plesiomonas shigelloides in Yaounde, Cameroon.

We investigated an acute foodborne outbreak in Yaounde, Cameroon, following a private party. Plesiomonas shigelloides, which has rarely been reported as the causative agent of foodborne outbreaks, was strongly suspected. The unusual short incubation period suggested the presence of a preformed toxin within the incriminated food.