Nasal carrier rates and antibiotic resistance of Staphylococcus aureus isolates from hospital and non-hospital populations,Addis Ababa

Surgical staff of five different hospitals and university biology students were screened for nasal carriage of Staphylococcus aureus: 32·4% of the surgical staff and 21·6% of the students were carriers. The rate for the hospital staff was significantly higher (χ² = 9·2, P<0·01). The carrier rates among the surgical staff varied between 59·1% for surgeons and 22·7% for other surgical staff.195 S. aureus strains were isolated: 109 from surgical staff and 86 from students. All were tested for their resistance to antibiotics. Resistance to penicillin was 86·2% and 74·4%, respectively, for hospital and non-hospital isolates. Resistance to erythromycin, gentamicin, kanamycin or co-trimoxazole was not detected among the non-hospital isolates. All isolates were sensitive to vancomycin, cephalothin and clindamycin. Over 96% and 88% of hospital and non-hospital isolates, respectively, were resistant to at least one antibiotic. About 45% of the hospital isolates and 2·3% of the non-hospital isolates showed multiple resistance.The rate of multiple resistance among the hospital staff isolates was considered high and indicative of still higher rates among clinical isolates. Further studies are suggested in order to take appropriate measures against bacterial resistance to antibiotics.     

Pattern of antibiotic and heavy-metal ion resistance in recent hospital isolates of Staphylococcus aureus

Two hundred and one strains of Staphylococcus aureus isolated from in-patients and out-patients were examined for sensitivity to antibiotics, heavy-metal ions and ethidium bromide and for phage-typing pattern. Heavy-metal ion resistance was less frequent than reported in previous studies and was as frequent in penicillinase non-producing as producing strains. 'Methicillin-resistant' strains were resistance to ethidium bromide and mercury. Resistance to heavy-metal ions, including cadmium, may be becoming less common amongst clinical isolates of S. aureus.     

Nasal carriage of methicillin-resistant Staphylococcus aureus among hospital staff and outpatients.

This study sought to determine the rate of nasal methicillin-resistant Staphylococcus aureus (MRSA) carriage among hospital staff and outpatients. Nasal swabs were obtained from 500 outpatients and 500 hospital staff. Hospital staff were 2.3-fold more likely to carry MRSA than were outpatients (6% vs 2.6%, P = .013).     

Nasal carriage of methicillin-resistant Staphylococcus aureus by hospital staff in north Jordan.

The nasal carriage of methicillin-resistant Staphylococcus aureus was detected in 550 hospital staff members of four hospitals in north Jordan. Of the 109 (19.8%) individuals tested who were nasal carriers of S. aureus, only 32 (5.8%) were found to be carriers of methicillin-resistant Staphylococcus aureus. The carriers were four doctors, 23 nurses, three laboratory technicians, one maid and an administrator. It was noted that 25 (78.1%) of these carriers were in constant contact with patients in operating theatres, surgical wards or intensive care units. It was not clear whether the carriers were short- or long-term carriers, or whether they were persistent sources of methicillin-resistant Staphylococcus aureus. Decontamination of these carriers was considered among other control measures to avoid the dangerous outcome of hospital outbreaks caused by this potential pathogen.     

Prevalence and antibiotic resistance of foodborne Staphylococcus aureus isolates in Turkey

Abstract In this study, 154 Staphylococcus aureus isolates were detected from 1070 food samples (14.4%) collected from seven cities in Turkey. Antimicrobial susceptibility testing against 21 antibiotics was performed by agar disk diffusion method, and those isolates resistant to any antibiotic were further analyzed to determine minimum inhibitory concentration by E-test and polymerase chain reaction analysis of vanA and mecA genes. According to disk diffusion test results, a total of 139 strains were resistant to at least one tested antibiotic, with 39 (25.3%) strains being multidrug resistant (MDR) and the other 15 strains being susceptible to all antibiotics. Penicillin G, linezolid, erythromycin, and tetracycline took up 71.4%, 23.4%, 18.2%, and 15.6% of the tested strains, respectively. In addition, all of the strains were susceptible to vancomycin, oxacillin, cefoxitin, and imipenem. Only one strain (S158B) was resistant to both teicoplanin and cefazolin. On the other hand, the presence of vanA and mecA genes was not detected in the strains. Pulsed-field gel electrophoresis analysis was used to identify genetic-relatedness of the MDR strains. It is noteworthy that some strains from different sources showed 100% homology; however, some of MDR strains were found unrelated with 60% or less homology. The high diversity observed in pulsed-field gel electrophoresis results indicated the possible contamination of S. aureus from different sources and routes.     

Long-term carriage, and transmission of methicillin-resistant Staphylococcus aureus after discharge from hospital.

The purpose of this study was to determine whether patients who become carriers of methicillin-resistant Staphylococcus aureus (MRSA) during their stay in hospital, remain colonized after discharge. Thirty-six patients colonized with MRSA during one of three outbreaks at Utrecht University Hospital (1986-89) were screened 2 or 3 years after they had become carriers. Patients were also interviewed to determine factors contributing to persistent carriage, such as antibiotics, re-admissions to the hospital, presence of skin lesions and chronic diseases. At the same time transmission of MRSA to family members was determined. The epidemic MRSA strain was still found in three patients (8%). One was a cystic fibrosis patient who had had frequent re-admissions to the hospital and had received several course of antibiotic treatment. Both of the other patients had skin lesions: a fistula and a colostomy respectively. None of the 44 family members of the patients was colonized or infected with MRSA. We conclude that long-term MRSA carriage occurs with low frequency and is comparable to persistent carriage of methicillin-sensitive Staphylococcus aureus (MSSA). Transmission of MRSA to healthy individuals in an antibiotic-free environment is a rare event.     

Methicillin-resistant Staphylococcus aureus in two tertiary-care centers in Jeddah, Saudi Arabia.

OBJECTIVE: To review clinical experience with methicillin-resistant Staphylococcus aureus (MRSA) in tertiary-care hospitals in Jeddah, Saudi Arabia. DESIGN: Retrospective review for the year 1998. SETTING: Two tertiary-care hospitals. METHODS: Results of MRSA-positive cultures of clinical specimens obtained as part of investigations for suspected infections were retrieved from the microbiology laboratories' records. Charts of patients were reviewed, with standardized data collection. RESULTS: Of 673 S. aureus isolates identified, 222 (33%, or 6.8 isolates/1,000 admissions) were MRSA. Overall MRSA prevalence was 2% in 1988. Nosocomial acquisition occurred in 84.2% of cases. All age groups were affected, and 52% of patients had at least one comorbidity. MRSA prevalence was highest in the intensive care units (26.6% of all isolates), the medical wards (24.8%), and the surgical wards (19.8%). Seventy-three percent of isolates caused infection; the rest represented colonization. Surgical wounds (35.2%), the chest (29%), and central venous catheters (13%) were the most common sites of infection. Bacteremia occurred in 15.4% of patients. Local signs (84%) and fever (75.9%) were the most common clinical manifestations. Respiratory distress and septic shock occurred in 30.2% and 13.6% of cases, respectively. Of 162 patients with MRSA infection and 60 patients with MRSA colonization, 95.7% and 70% received antibiotics in the preceding 6 weeks, respectively (P<.0001). The total mortality of patients with MRSA infection was 53.7%: 36.4% as a result of MRSA infection and 17.3% as a result of other causes. CONCLUSIONS: The prevalence of MRSA is high and rapidly increasing in the two hospitals, as it is worldwide. Control measures to prevent the spread of MRSA in hospitals should continue, with reinforcement of hygienic precautions and development of policies to restrict the use of antibiotics.     

Assessment of inhalation technique in children with asthma, Abha, Saudi Arabia

The inhalation technique of asthma in children was assessed using the criteria defined by the standardized inhaler checklist of the Netherlands Asthma Foundation and Dutch asthma foundation. Four hundred and thirty seven newly referred patients to chest clinic, department of pediatric, Assir Central Hospital, Southwestern Saudi Arabia were instructed to demonstrate their inhalation technique and to fill out a questionnaire related to the inhalation instructions received before their referral. Results: Four hundred and thirty seven patients newly referred for evaluation of their asthma (5-12 years of age with mean age of 7.16+1.69 years, 202 (46.2%) girls, 235 (53.8%) boys were included in the study. Two hundred two (46.2%) patients use MDI. The remaining (53.8%) patients use the DPI, 123 (52.35%) of them use turbohalers while 112 (47.65%) use diskhalers. Only 36 patients (8.2 %) completed the assessment without making any mistake. Of the remainders, 399 (91.8%) made one or more mistakes. Of the MDI users, eleven patients (5.4%) performed correctly all the steps, and 54 (26.7%) performed correctly four or more steps. Ten (8.9%) of the diskhaler users performed all the steps correctly and forty nine (43.8) performed correctly four or more steps. Fifteen (12 2%) of the turbohaler users performed correctly all the steps and ninety five (77.2%) performed correctly four or more steps. One hundred five of the male patients (44.7%), performed correctly more than three steps as compared to 93 of the female patients (46.5) with p value=0.704. One hundred and one patients (67.3%) between the age of 8-12 years performed more than three steps correctly as compared to 97 (33.8%) of patients aged 5-7 years (p=0.001). Conclusion: In conclusion, many asthmatic children use their inhaler devices too poorly with the result of an unreliable drug delivery. Turbohaler device inhalation technique was the easiest, followed by diskhaler then lastly the MDI. Education of asthmatic children and their families is highly needed to make sure the patient perform the correct inhalation technique.     

Antimicrobial sensitivity patterns of hospital and non-hospital strains of Staphylococcus aureus isolated from nasal carriers.

The nasal carriage rate of Staphylococcus aureus was significantly higher in hospitalized persons (children, adult females and staff) - 53.8%, - than in similar persons at a local clinic - 29.8% (P less than 0.001) - in Ile-Ife, Nigeria. However, unlike studies carried out elsewhere, a higher proportion of S. aureus strains obtained from persons at the clinic were resistant to commonly used antimicrobial agents than were strains isolated in the hospital. This has been attributed to the ease at which these drugs can be obtained by the general population and used unsupervised and indiscriminately. Methicillin was the most effective antimicrobial agent against pathologic staphylococci (2.2% resistance), followed by erythromycin (16.5% resistance), co-trimaxozole (28.0% resistance), chloramphenicol (76.9% resistance), tetracycline (78.6% resistance) and penicillin and ampicillin (97.8% resistance). The widespread resistance of S. aureus to penicillin and ampicillin (and other antimicrobial agents) is of clinical significance in the treatment of post-operative infections, since carriers are reportedly more prone to such infections than are non-carriers.     

Nasal carriage of methicillin-resistant Staphylococcus aureus in an American Indian population.

BACKGROUND AND OBJECTIVE: Although reports of methicillin-resistant Staphylococcus aureus (MRSA) infections without healthcare exposure are increasing, population-based data regarding nasal colonization are lacking. We assessed the prevalence of and risk factors for community-associated MRSA nasal carriage in patients of a rural outpatient clinic. DESIGN: A cross-sectional population survey was conducted through random sample and stratification by community of residence. Recent healthcare exposure (ie, hospitalization, dialysis, or healthcare occupation) and other risk factors for MRSA carriage were assessed. Cultures of the nares were performed. Community-associated MRSA was defined as MRSA carriage without healthcare exposure. SETTING: A predominantly American Indian community in Washington. PATIENTS: Those receiving healthcare from an Indian Health Service clinic. RESULTS: Of 1,311 individuals identified for study, 475 (36%) participated. Unsatisfactory culture specimens resulted in exclusion of 6 participants. In all, 128 (27.3%) of 469 participants had S. aureus. Nine (1.9%) of 469 had MRSA carriage; of these, 5 had community-associated MRSA (5 of 469; overall community-associated MRSA carriage rate, 1.1%). MRSA carriage was associated with antimicrobial use in the previous year (risk ratio [RR], 7.2; P = .04) and residence in a household of more than 7 individuals (RR, 4.5; P = .03). Pulsed-field gel electrophoresis indicated that 5 (55%) of 9 MRSA carriage isolates were closely related, including 3 (60%) of 5 that were community associated. CONCLUSIONS: Prevalence of community-associated MRSA colonization was approximately 1% in this rural, American Indian population. Community-associated MRSA colonization was associated with recent antimicrobial use and larger household.     

Health services utilization patterns of two urban communities in Abha,Saudi Arabia

A 20% random sample of 146 families including 942 individuals was selected from two urban communities in Abha City in Saudi Arabia in order to assess the pattern of health services utilization. The information was obtained from the heads of families through interviews using a structured questionnaire. Health wants of the people to improve health services were also determined.Of all the health problems encountered in the sample, 84% received health services from the Primary Health Care Center (PHCC) and from the hospital out-patient department. Seventy percent of the deliveries were conducted at the hospital, and the average hospital stay for a delivery was 2.9 days. The overall annual hospitalization rate for the population under study was 89 per 1,000 population, with an average hospitalization period of 7.5 days per case. Deliveries constituted the leading cause for hospitalization.Only 52% of the deliveries received postnatal care, mostly in the hospital, whereas 88 per cent of the pregnancies received antenatal care, mainly in the PHCC. The outreach services of the PHCC were very deficient and lacked the basic elements of preventive services. The role of the hospital and PHCC should be adjusted to meet the health needs of the people, and the people's health wants which reflect their sociocultural background should be given attention in health planning.Dr. Hassan A. H. Abu-Zeid is Professor and Chairman, Department of Family and Community, Medicine Faculty of Medicine, King Saud University, Abha Branch. Supported by a Research Grant from the College of Medicine Research Center (CMRC), Faculty of Medicine King Saud University, AbhaWe are indebted to the Dr. G. Jamjoom, Dean of the Medical College at Abha, to Mr. O. Zoghaiby, the Director General of Health Services and Mr. A. Al-Torky the Director of Primary Health Care in Asir region, Saudi Arabia, and to the Director and staff of Al-Manhal Primary Health Care Center for their support and cooperation.The following pre-final year medical students have actively participated in the field work, data collection, and analysis: Mohammad A.M. Dallak, Talat E. Ardi, Mohammad A. Gasadi, Mohammad N. Halawani, Ibrahim A. Kutbi, Maged H. Attas, Assad A. Al-Motawa, Mohammad A. Shawoosh, Mohammad O. Safar, Mohammad A. Al-Zaharani, Faisal M. Al-Kahtani, and Mohammad S. Al-Ghamdi.     

健康儿童鼻携带金黄色葡萄球菌耐药性研究

摘要:目的　探讨广州在校健康儿童金黄色葡萄球菌鼻携带率及该菌对常见抗生素的耐药性。方法　广州市荔湾区抽取1间幼儿园和1间小学,对纳入研究对象采集鼻拭子进行金黄色葡萄球菌分离鉴定,并对阳性菌株进行抗生素药物敏感性检测。结果　共纳入463名幼儿园儿童及1 012名小学生,小学生金黄色葡萄球菌鼻携带率（40.1%）比幼儿园儿童（31.1%）高,其差异有统计学意义（χ2＝11.05,P＜0.05）。药敏结果显示,耐甲氧西林金黄色葡萄球菌（Methicillin-Resistant Staphylococcus Aureus,MRSA）呈多药耐药状态,其对四环素、红霉素及克林霉素的耐药率远高于甲氧西林敏感金黄色葡萄球菌（Methicillin-Sensitive Staphylococcus Aureus,MSSA）,差异有统计学意义（P值均＜0.05）。结论　广州荔湾区在校健康儿童鼻携带金黄色葡萄球菌较高,健康儿童鼻携带金黄色葡萄球菌高耐青霉素、红霉素及克林霉素。建议开展全国性监测,为临床医生合理用药提供参考依据。     

Increasing antibiotic resistance among isolates of Escherichia coli recovered from inpatients and outpatients in a Saudi Arabian hospital.

OBJECTIVE: To study the pattern of antibiotic resistance among Escherichia coli and the trend in resistance during a 6-year period in a Saudi Arabian hospital. DESIGN: Retrospective in vitro surveillance study of the antibiotic susceptibility pattern among E. coli isolates recovered from outpatients and from inpatients. SETTING: A general hospital in Saudi Arabia. PATIENTS: All patients with a culture positive for E. coli during a 6-year study period. RESULTS: A statistically significant increase in antibiotic resistance was observed among outpatient and inpatient isolates of E. coli. Inpatient isolates were more likely to be resistant to antimicrobial agents. Among isolates from outpatients, 50% were resistant to ampicillin, 33% were resistant to trimethoprim-sulfamethoxazole (TMP-SMZ), and 14% were resistant to ciprofloxacin. Among isolates from inpatients, 63% were resistant to ampicillin, 44% were resistant to TMP-SMZ, and 33% were resistant to ciprofloxacin. There was a low rate of resistance to imipenem (0.3% of isolates), amikacin (2%), and nitrofurantoin (2.4%-6.5%). Resistance to ceftazidime was detected in 9% of outpatient isolates and 17% of inpatient isolates. Multidrug resistance was defined as resistance to 2 or more classes of antibiotics. Multidrug resistance was detected in 2.0%-28.1% of outpatient isolates and 7.4%-39.6% of inpatient isolates, depending on the combination of antimicrobials tested. More isolates were resistant to ampicillin plus TMP-SMZ than to any other combination of antimicrobials. CONCLUSION: The prevalence of antibiotic resistance among outpatient and inpatient E. coli isolates increased during the study period. The rates of antibiotic resistance were statistically significantly higher among inpatient isolates, compared with outpatient isolates. These findings call for wiser use of antibiotics and continued surveillance of antibiotic resistance.     

Nasal carriage of enterotoxin-producing Staphylococcus aureus among restaurant workers in Kuwait City.

Enterotoxin-producing Staphylococcus aureus is a common cause of staphylococcal food poisoning. To determine the incidence of carriage of enterotoxin-producing S. aureus in a sample of the healthy population in Kuwait city, restaurant workers in the city were screened for nasal carriage of S. aureus. 26.6% of 500 workers studied carried S. aureus and 86.6% of the S. aureus produced staphylococcal enterotoxins. 28% produced enterotoxin A, 28.5% produced enterotoxin B, 16.4% produced enterotoxin C and 3.5% produced enterotoxin D. Ten isolates produced both enterotoxins A and B or A and C. 73% of the isolates were untypeable with standard phages. However, 17.1%, 3% and 6% belonged to phage groups I, II and III respectively. The results demonstrated a high level of enterotoxigenic S. aureus carriage among restaurant workers which although lower than that reported for the general population and hospital workers may be important in the restaurant industry.