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Background Many people use handwashing and hand-drying facilities in public washrooms under the impression that these amenities are hygienic. However, such facilities may be potential sites for the transmission of pathogenic bacteria. This study aimed to examine the hygiene facilities provided including handwashing and hand-drying facilities in public washrooms. Total bacterial counts and species identification were determined for hand-drying facilities. Antimicrobial susceptibilities were performed. Methods The bacterial contamination levels of 55 public washrooms ranging in category from low class communities to high end establishments, were examined. The hygienic environment and facilities of the washrooms were analysed using an electronic checklist to facilitate immediate data entry. Pre-moistened sterile swabs were used to collect samples from areas around the outlet of paper towel dispensers, air outlet of air dryers, exit door handles and paper towels in the washrooms. Total bacterial counts were performed and isolates identified using matrix-assisted laser desorption ionisation time-of-flight mass spectrometry. Antimicrobial susceptibility was determined by disk diffusion. Results The high and middle-income categories washrooms generally had cleaner facilities and environment followed by those in low categories. Fifty-two bacterial species were identified from the 55 investigated washrooms. Over 97% of the pathogenic Staphylococcus spp. tested were resistant to at least one first-line antimicrobial therapeutic agent, including penicillin, cefoxitin, erythromycin, co-trimoxazole, clindamycin and gentamicin, and 22.6% demonstrated co-resistance to at least three antimicrobial agents, with co-resistance to penicillin, erythromycin and clindamycin being the most common. Conclusion Our findings suggest that hand-drying facilities in public washrooms can act as reservoirs of drug-resistant bacteria. The importance of frequent cleaning and maintenance of public washrooms to promote safe hand hygiene practices for the public are emphasised. Electronic supplementary material The online version of this article (10.1186/s13756-019-0500-z) contains supplementary material, which is available to authorized users.

Background The adequate fit of an N95 respirator is important for health care workers to reduce the transmission of airborne infectious diseases in the clinical setting. This study aimed to evaluate whether adequately sealed N95 respirators may provide consistent protection for the wearer while performing nursing procedures. Methods Participants were a group of nursing students (N = 120). The best fitting respirator for these participants was identified from the 3 common models, 1860, 1860S, and 1870+ (3M), using the quantitative fit test (QNFT) method. Participants performed nursing procedures for 10-minute periods while wearing a backpack containing the portable aerosol spectrometers throughout the assessment to detect air particles inside the respirator. Results The average fit factor of the best fitting respirator worn by the participants dropped significantly after nursing procedures (184.85 vs 134.71) as detected by the QNFT. In addition, significant differences in particle concentration of different sizes (>0.3, >0.4, >1.0, and >4.0 µm) inside the respirator were detected by the portable aerosol spectrometers before, during, and after nursing procedures. Conclusions Body movements during nursing procedures may increase the risk of face seal leakage. Further research, including the development of prototype devices for better respirator fit, is necessary to improve respiratory protection of users.

Background Hand hygiene is a critical component of infection control. Much of the focus on improving hand hygiene in healthcare settings has been directed towards healthcare worker compliance but its importance for patients, including those in long-term care facilities (LTCFs), is increasingly being recognised. Alcohol-based hand rub (ABHR) can lead to improved compliance. We aimed to determine acceptability and tolerability of two ABHRs for hand hygiene of elderly LTCF residents using a modified version of the WHO protocol. Methods Thirty six elderly LTCF residents participated in this crossover study. A modified and translated (Chinese) version of the WHO protocol for evaluation of two or more ABHRs was used to determine product acceptability and tolerability for one gel (bottle with reclosable cap) and one foam (pump). During the 3-day testing period, participants were provided with their own portable bottle of ABHR. A research nurse objectively assessed the skin integrity of the hands at baseline and throughout the study. Skin moisture content was determined using a Scalar Moisture Checker Probe (Science Technology Resources, Ca, USA). Participants rated ABHR tolerability and acceptability using the WHO checklist at the end of each test period. Results Both products passed the WHO criteria for acceptability and tolerability. The foam (86%) scored higher than the gel (51%) for ease of use possibly because some participants found the cap of the gel bottle difficult to open due to finger stiffness. No evidence of damage to skin integrity was observed. Overall, skin moisture content had improved by the end of the study. Residents preferred either of the test products to the liquid formulation currently in use by the LTCF. Conclusions Overall, the elderly were willing to use ABHR for hand hygiene. Both products were well tolerated and preferred over the usual product provided by the LTCF. However, forgetfulness and difficulty rubbing the product over the hands due to finger stiffness posed a challenge for some residents. This could be overcome by using healthcare worker-assisted hand hygiene at specified times each day and prompts to serve as reminders to perform hand hygiene.

BACKGROUND The goal of antiretroviral therapy (ART) is to reduce HIV-related morbidity and mortality by suppressing HIV replication. The prognostic value of persistent low-level viremia (LLV), particularly for clinical outcomes, is unknown. OBJECTIVE Assess the association of different levels of LLV with virological failure, AIDS event, and death among HIV-infected patients receiving combination ART. METHODS We analyzed data from 18 cohorts in Europe and North America, contributing to the ART Cohort Collaboration. Eligible patients achieved viral load below 50 copies/ml within 3-9 months after ART initiation. LLV50-199 was defined as two consecutive viral loads between 50 and 199 copies/ml and LLV200-499 as two consecutive viral loads between 50 and 499 copies/ml, with at least one between 200 and 499 copies/ml. We used Cox models to estimate the association of LLV with virological failure (two consecutive viral loads at least 500 copies/ml or one viral load at least 500 copies/ml, followed by a modification of ART) and AIDS event/death. RESULTS Among 17 902 patients, 624 (3.5%) experienced LLV50-199 and 482 (2.7%) LLV200-499. Median follow-up was 2.3 and 3.1 years for virological and clinical outcomes, respectively. There were 1903 virological failure, 532 AIDS events and 480 deaths. LLV200-499 was strongly associated with virological failure [adjusted hazard ratio (aHR) 3.97, 95% confidence interval (CI) 3.05-5.17]. LLV50-199 was weakly associated with virological failure (aHR 1.38, 95% CI 0.96-2.00). LLV50-199 and LLV200-499 were not associated with AIDS event/death (aHR 1.13, 95% CI 0.81-1.68; and aHR 0.95, 95% CI 0.62-1.48, [corrected] respectively). CONCLUSION LLV200-499 was strongly associated with virological failure, but not with AIDS event/death. Our results support the US guidelines, which define virological failure as a confirmed viral load above 200 copies/ml.

SUMMARYA longitudinal study of nasal colonization and hand contamination of food handlers withStaphylococcus aureuscommenced in 2002 prior to the outbreak of severe acute respiratory syndrome. In the follow-up in 2003 when hygiene measures were strictly implemented, significant reductions in carriage were observed. To investigate if this change was sustained, nasal and hand carriage rates were compared between the earlier studies and a further sampling in 2011. The initial nasal carriage rate was 35% and hand contamination 41·2%, decreasing to 23·5% and 11·6%, respectively in 2003 (P< 0·001). In 2011, nasal carriage was similar to 2003 (22·9%), while hand contamination dropped further to 3·7% (P< 0·001).Spa-typing revealed 39 types in 2002 and 42 in 2011. This study reveals that the marked reduction in colonization had been sustained. This may be attributed to reduced opportunities for spread due to enhanced hygiene and reinforces its importance for control of disease.

We aimed to identify the source of Staphylococcus aureus contaminating hands of food handlers. Nasal samples and direct fingertip imprints were collected on 2 occasions from food handlers and characterized to determine likely sources of hand contamination. Most hand contamination was attributable to nasal isolates of persistently colonized coworkers who had presumably contaminated the environment. Regular handwashing should be supplemented by effective environmental disinfection., Highlights • We aimed to identify the source of S. aureus contaminating hands of food handlers. • Persistently colonized co-workers indirectly contaminated hands of others. • Regular handwashing should be supplemented by effective environmental disinfection.

Background Whilst numerous studies have investigated nurses’ compliance with hand hygiene and use of alcohol-based hand rub (ABHR), limited attention has been paid to these issues in allied health staff. Reports have linked infections to breaches in infection control in the radiography unit (RU). With advances in medical imaging, a higher proportion of patients come into contact with RU staff increasing the need for good hand hygiene compliance. This study aimed to evaluate effectiveness on compliance of an intervention to improve awareness of hand hygiene in the RU of a district hospital. Methods A quasi-experimental study design including questionnaires assessing knowledge and attitudes of hand hygiene and direct observation of participants was used to evaluate an educational programme on hand hygiene of the RU of a large district hospital. All healthcare workers (HCW), comprising 76 radiographers, 17 nurses, and nine healthcare assistants (HCA), agreed to participate in the study. Of these, 85 completed the initial and 76 the post-test anonymous questionnaire. The hand hygiene compliance of all 102 HCW was observed over a 3-week period prior to and after the intervention. The 2-month intervention consisted of talks on hand hygiene and benefits of ABHR, provision of visual aids, wall-mounted ABHR dispensers, and personal bottles of ABHR. Results Before the intervention, overall hand hygiene compliance was low (28.9 %). Post-intervention, compliance with hand hygiene increased to 51.4 %. This improvement was significant for radiographers and HCA. Additionally, knowledge and attitudes improved in particular, understanding that ABHR can largely replace handwashing and there is a need to perform hand hygiene after environmental contact. The increased use of ABHR allowed HCW to feel they had enough time to perform hand hygiene. Conclusions The educational intervention led to increased awareness of hand hygiene opportunities and better acceptance of ABHR use. The reduced time needed to perform hand rubbing and improved access to dispensers resulted in fewer missed opportunities. Although radiographers and other allied HCW make frequent contact with patients, these may be mistakenly construed as irrelevant with respect to healthcare associated infections. Stronger emphasis on hand hygiene compliance of these staff may help reduce infection risk.

Background Influenza often causes winter and summer epidemics in subtropical regions, but few studies have investigated the difference in healthcare seeking behavior of patients with influenza-like illness (ILI) between these two epidemics. Methods Household telephone surveys were conducted using random digit dialing in Hong Kong during July-August 2014 and March-April 2015. One adult from each household was interviewed for ILI symptoms and associated healthcare seeking behaviour of themselves and one child in the household (if any), during the preceding 30 days. Healthcare seeking behavior of respondents with self-reported ILI was compared between summer and winter influenza. Logistic regression was used to explore the factors associated with healthcare seeking behavior. Results Among 516 and 539 adult respondents in the summer and winter surveys, 22.6 and 38.0 % reported ILI symptoms, and 40.9 and 46.8 % of them sought medical care, respectively. There was no significant difference in healthcare seeking behavior between the summer and winter epidemics, except a higher proportion of self-medication in summer in the adult respondents. Among 155 and 182 children reported by the adults in both surveys, the proportion of self-reported ILI was 32.9 and 40.1 % in the summer and winter surveys, respectively. Of these children, 47.1 and 56.2 % were brought for medical consultation in summer and winter, respectively. Women, adults with diabetes and those with symptoms of cough, shortness of breath, and runny nose were more likely to seek medical consultations for ILI symptoms. The factors associated with seeking medical consultations in children with ILI symptoms included being female, age under 10 years, and with symptoms of sore throat or vomiting. Those older than 60 years were less likely to self-medicate, whereas regular smokers and those with symptom of sore throat were more likely to do so. Conclusion Healthcare seeking behavior of the general public was not significantly different between these two epidemics. However ILI was associated with increased healthcare utilization in both winter and summer epidemics in Hong Kong. Electronic supplementary material The online version of this article (doi:10.1186/s12879-016-1821-7) contains supplementary material, which is available to authorized users.

Contains fulltext : 70499.pdf (Publisher’s version ) (Closed access) OBJECTIVE: To determine whether differences in short-term virologic failure among commonly used antiretroviral therapy (ART) regimens translate to differences in clinical events in antiretroviral-naive patients initiating ART. DESIGN: Observational cohort study of patients initiating ART between January 2000 and December 2005. SETTING: The Antiretroviral Therapy Cohort Collaboration (ART-CC) is a collaboration of 15 HIV cohort studies from Canada, Europe, and the United States. STUDY PARTICIPANTS: A total of 13 546 antiretroviral-naive HIV-positive patients initiating ART with efavirenz, nevirapine, lopinavir/ritonavir, nelfinavir, or abacavir as third drugs in combination with a zidovudine and lamivudine nucleoside reverse transcriptase inhibitor backbone. MAIN OUTCOME MEASURES: Short-term (24-week) virologic failure (>500 copies/ml) and clinical events within 2 years of ART initiation (incident AIDS-defining event, death, and a composite measure of these two outcomes). RESULTS: Compared with efavirenz as initial third drug, short-term virologic failure was more common with all other third drugs evaluated; nevirapine (adjusted odds ratio = 1.87, 95% confidence interval (CI) = 1.58-2.22), lopinavir/ritonavir (1.32, 95% CI = 1.12-1.57), nelfinavir (3.20, 95% CI = 2.74-3.74), and abacavir (2.13, 95% CI = 1.82-2.50). However, the rate of clinical events within 2 years of ART initiation appeared higher only with nevirapine (adjusted hazard ratio for composite outcome measure 1.27, 95% CI = 1.04-1.56) and abacavir (1.22, 95% CI = 1.00-1.48). CONCLUSION: Among antiretroviral-naive patients initiating therapy, between-ART regimen, differences in short-term virologic failure do not necessarily translate to differences in clinical outcomes. Our results should be interpreted with caution because of the possibility of residual confounding by indication.

This study investigated the association between the presence of staphylococcal enterotoxin (SE) genes and nasal carriage status, and determined temporal changes in the prevalence of these genes in Staphylococcus aureus strains isolated from healthy carriers between 2002 and 2011. Three large samples of food handlers recruited in 2002, 2003 and 2011 were nasally sampled on two occasions to determine S. aureus colonisation status. Those carrying the same spa type on both occasions were defined as persistent carriers. Genes for SEs SEA–SEU were amplified and associations between carriage status and presence of SE genes were investigated. Although 80 % of nasal isolates harboured at least one SE gene over the sampling period, persistent carriers were significantly more likely to harbour enterotoxigenic S. aureus than transiently colonised subjects [odds ratio (OR) 2.52–3.06]. Strains from persistent carriers more commonly harboured sea, seb and sem. The prevalence of classical SE genes and sej, sem, sen, seo, seq and ses was stable over time, but seh, sel, sep, ser, set and selu increased significantly. Increased toxigenicity of isolates from persistent carriers is consistent with the elevated antibody levels to classical SEs previously reported in persistent carriers, supporting the hypothesis that superantigen production in the nasal cavity may enhance colonisation.

Our purpose was to estimate the rate of carriage of vancomycin-resistant enterococci (VRE) in hospitalized patients in a district hospital and in healthy subjects in the community in Hong Kong. Rectal swabs were collected from all patients admitted to the intensive care unit, and stool specimens were collected from all patients presenting with suspected antibiotic-associated diarrhea over a 2-month period. Stool specimens were also collected from healthy subjects in the community. Specimens were enriched and cultured on selective media for the isolation of enterococci. All isolates were identified, and their minimum inhibitory concentration for vancomycin was determined. Susceptibility to other antibiotics was investigated. Samples yielded 125 isolates of enterococci, the majority of isolates being Enterococcus faecalis (75) and E. faecium (35). Nine of 11 strains of E. gallinarum and 2 of 2 strains of E. casseliflavus isolated from hospitalized patients were intermediately resistant to vancomycin, but no strains highly resistant to vancomycin were isolated. Resistance to other drugs, including the fluoroquinolones, was present, and a high-level resistance to gentamicin and streptomycin was found in 37% and 46% of strains, respectively. Colonization with VRE remains low in Hong Kong. This result is supported by the low level of isolation of VRE from infections in the region and may be attributable to low levels of vancomycin use. High-level aminoglycoside resistance and fluoroquinolone resistance are common, and continued monitoring for VRE is suggested.

Ten methicillin-resistant Staphylococcus aureus (MRSA) isolates from healthy owners and their pets were characterised by susceptibility testing, staphylococcal chromosome cassette (SCC)mec and agr typing, and detection of the Panton–Valentine leukocidin (PVL) genes. Two human and three dog isolates harbouring SCCmec type III appeared to be of hospital origin. The five remaining isolates carried SCCmec type IV, with three being multidrug-resistant. One type IV isolate was PVL-positive and a prototypic agr type 3, typified by strain MW2. This is the first report of this type in association with nasal carriage. Drug resistance may be increasing among community isolates of MRSA.

Problems of vancomycin non-susceptible Staphylococcus aureus (VISA) and subsequent treatment failure are increasing. This study aimed to observe development and loss of vancomycin non-susceptibility, determine exposure time needed for resistance development, and follow mutations in the VraSR and GraSR two-component systems during these processes.Sequences of vraS, graR and rpoB, proposed as critical sites of mutation associated with non-susceptibility development, were compared in susceptible clinical methicillin-resistant S. aureus isolates both initially and following vancomycin induction and its withdrawal, to identify mutations. Mutations were correlated with exposure time, increase in vancomycin MIC and phenotypic changes.Both time required for heterogeneous VISA and VISA development, and maximum MIC attained (6-20 mg/L) varied between strains. Sequence analysis revealed the presence of stop codons in an initial strain with delayed non-susceptibility development. Other changes in vraS and graR occurred during VISA development in all isolates. After removal of vancomycin pressure, most strains reverted to susceptibility accompanied by emergence of stop codons in both vraS and graR. One strain not displaying stop codons remained resistant in the absence of vancomycin pressure. A substitution in GraR (D148Q) appeared to be associated with an elevated MIC (20 mg/L). No rpoB mutations were observed throughout VISA development.Vancomycin non-susceptibility developed in all strains tested. Mutations in vraS and graR appeared to be essential for VISA development, with stop codons playing an important role in delaying non-susceptibility development and reversion. Absence of mutations in rpoB suggests that these are not essential for vancomycin resistance. Further work is required to confirm consistent changes involved in non-susceptibility development.

Reports have documented colonization of swine in Europe, North America and more recently in China with livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA). Contamination of pig farmers, veterinarians and abattoir workers with these strains has been observed. However, although contamination levels of 10% of retail pork were reported from the Netherlands and Canada, there are limited data of contamination rates of workers handling raw meat. We investigated the rates of MRSA contamination of local butchers working in wet markets, where recently slaughtered pigs are cut up. Nasal swabs collected from 300 pork butchers at markets throughout Hong Kong were enriched in brain heart infusion broth with 5% salt and cultured on MRSASelect(®) . Isolates were confirmed as Staphylococcus aureus and susceptibility testing performed. The presence of mecA was confirmed, SCCmec and spa type determined and relatedness investigated by PFGE. Subjects completed a questionnaire on MRSA carriage risk factors. Seventeen samples (5.6%) yielded MRSA, 15 harbouring SCCmec IVb. Ten strains were t899 (CC9), previously reported from local pig carcasses. Five strains were healthcare associated: SCCmec type II, t701(CC6), colonizing two subjects at the same establishment, and single isolates of t008 (CC8), t002 (CC5) and t123 (CC45). The remaining isolates were t359 (CC97), previously reported from buffaloes, and t375 (CC5), reported from bovine milk. None of these butchers reported recent hospitalization or a healthcare worker in the family. Two had recently received antibiotics, one for a skin infection. Four reported wound infections within the last year. All were exposed to meat for >9 h per day. Carriage of MRSA was higher in butchers than in the general community. Although five strains were probably of healthcare origin, the high incidence of t899 (CC9) suggests that cross-contamination from pork occurs frequently. Washing of hands after touching raw pork is advised.

We investigated changes in regulatory genes, vraS and graR, during development of vancomycin non-susceptibility in a patient with methicillin-resistant Staphylococcus aureus who failed therapy and following in-vitro vancomycin exposure and a subsequent drug-free growth period. Minimum Inhibitory Concentration (MICs) were determined and genes sequenced at each stage. After 30 days of vancomycin exposure, the strain attained maximum MIC (20 mg/L) and was resistant to all antibiotics. Reversion to vancomycin susceptibility occurred 21 days after removal. We observed mutations in vraS and graR during non-susceptibly development and novel stop codons in the reverted strain. Mutations in graR appear important for development of intermediate susceptibility to vancomycin. The results suggest that monitoring of vancomycin therapy could allow earlier change to appropriate agents.

Background: The generalizability of antiretroviral therapy (ART) clinical trial efficacy findings to routine care settings is not well studied. We compared the relative effectiveness of initial ART regimens estimated in AIDS Clinical Trial Group (ACTG) randomized controlled trials with that among patients receiving ART at Antiretroviral Therapy Cohort Collaboration (ART-CC) study sites. Methods: Treatment-naive HIV-infected patients initiating identical ART regimens in ACTG trials (A5095 and A5142) and at 15 ART-CC cohort study sites were included. Virological failure (HIV-1 RNA.200 copies/mL) at 24 and 48 weeks, incident AIDS-defining events and mortality were measured according to study design (ART-CC cohort vs. ACTG trial) and stratified by third drug [abacavir (ABC), efavirenz (EFV), and lopinavir/r (LPV/r)]. We used logistic regression to estimate and compare odds ratios (OR) for virological failure between different regimens and study designs, and used Cox models to estimate and compare hazard ratios for AIDS and death. Results: Compared with patients receiving ABC, those receiving EFV had roughly half the odds of 24-week virologic failure (>200 copies/mL) in both ACTG 5095 (OR = 0.53, 95% confidence interval: 0.36 to 0.79) and ART-CC (0.46, 0.37 to 0.57). Virologic superiority of EFV (vs. ABC) seemed comparable in ART-CC and ACTG 5095 (ratio of ORs 0.86, 95% confidence interval: 0.54 to 1.35). Odds ratios for 48-week virologic failure, comparing EFV with LPV/r, were also comparable in ACTG 5142 and ART-CC (ratio of ORs: 0.87, 0.45 to 1.69). Conclusions: Between ART regimen virologic efficacy of third drugs ABC, EFV, and LPV/r observed in the ACTG 5095 and 5142 trials seem generalizable to the routine care setting of ART-CC clinical cohorts.

Objectives: Several methods have been introduced for detection of vancomycin-non-susceptible Staphylococcus aureus [heterogeneous vancomycin-intermediate S. aureus (hVISA) and vancomycin-intermediate S. aureus (VISA)]. However, the limitations of these methods can delay appropriate therapy for the patient. This study evaluated the spiral gradient endpoint (SGE) technique for detection of hVISA/VISA. Methods: The SGE method was evaluated for intra-batch, inter-batch and inter-observer reproducibility in comparison with MICs determined by agar dilution. Three media, Mueller-Hinton agar, brain heart infusion agar and brain heart infusion agar with 5% glucose, were evaluated. The SGE method was compared with agar dilution for correlation of MIC and susceptibility category using control strains, clinical isolates and induced vancomycin-non-susceptible strains. Results: The SGE method had good reproducibility and there was excellent correlation of MICs generated by SGE using brain heart infusion agar with those by agar dilution (r 2 = 0.950), with no difference in resistance categories generated by the two methods. All VISA isolates were correctly identified and the method allowed easy identification of hVISA by means of the trailing endpoint. Conclusions: SGE offers a simple, rapid and cost-effective alternative method for the detection of hVISA/VISA for the routine laboratory. Early recognition of vancomycin-non-susceptible strains can allow the change to appropriate antibiotics, resulting in potentially better patient outcomes.

Objectives: Increasing antibiotic resistance and interest in matching antibiotic therapy with pharmacokinetic/ pharmacodynamic characteristics of isolates has led to increasing demands for determination of MICs. This can lead to increased costs for the laboratory. The spiral gradient endpoint (SGE) technique, a low-cost method of MIC determination, was developed some years ago. Although the technique showed good correlation with reference methods, it was not widely employed, mainly due to the introduction of alternative methods. We have revisited this technique and evaluated it for the determination of MICs for fastidious organisms. Methods: The SGE method was first optimized for fastidious organisms using Haemophilus influenzae. Intrabatch and inter-batch reproducibility was determined for H. influenzae, Streptococcus pneumoniae, Moraxella catarrhalis and Neisseria gonorrhoeae. The method was then evaluated by comparison of MICs for clinical isolates of these organisms determined by SGE with those determined with the reference method. Results: Optimization of the technique resulted in a method with excellent reproducibility for all organisms tested [SD 0.10‐0.337; coefficient of variation (CV) 8.59%‐18.66%]. These SDs/CVs were lower than those of the reference methods (0.27‐2.34; 31.0%‐63.8%). There was excellent correlation of the MICs with the reference methods (0.908‐0.930) and insignificant differences in numbers of strains in each resistance category, with no tendency for SGE to produce higher or lower MICs than the reference method (P .0.05). Conclusions: SGE was shown to be reproducible and produced results that correlated well with standard techniques for fastidious organisms. The method offers a rapid, flexible, cost-effective alternative for smaller laboratories and for routine use in developing countries.

Although reports of isolation of methicillin-resistant Staphylococcus aureus (MRSA) from patients admitted from the community have increased, few studies have investigated colonization of healthy subjects. This study aimed to determine community levels of MRSA in Hong Kong. Nasal swabs from a cross section of young adults and family units were cultured for MRSA. Antibiotic sensitivities and risk factors for carriage were determined and clonal relationships were investigated by pulsed-field gel electrophoresis (PFGE). Overall carriage was low (1·4%), and associated with health-care exposures (OR 13·56, 95% CI 1·11–165·21). Subjects working in health care yielded multi-resistant MRSA strains, but isolates from non-hospital-exposed subjects were methicillin-resistant only. Strains indistinguishable by PFGE were carried by subjects working together, and some spread to other contacts was observed. MRSA colonization in the community is rare in Hong Kong and is largely associated with working in health care. Community-acquired staphylococcal infections may be treated with agents effective against methicillin-sensitive strains.

OBJECTIVES\ud \ud To estimate life expectancy for people with HIV undergoing treatment compared with life expectancy in the general population and to assess the impact on life expectancy of late treatment, defined as CD4 count

The question "what are 'pin-point' colonies?" has puzzled workers in dairies and scientific laboratories since the World War, 1914 to 1918. At that time, the importation of German products for culture mediums was prevented and America had to use domestic products. A condition arose simultaneously in the bacteriologic analysis of milk for a new type of colony appeared at times on the agar plates used in routine analysis. These colonies were very minute and Jacobsen (Fay, p. 350)11 was the first to deal with the problem of the "pin-point colony." Since the time these colonies were first recognized, numerous workers have tried experimentation with these organisms in milk. The greatest difficulty seemed to be that "pin-point" was such a flexible term and might embrace any colony that was minute. Ayers and Johnson 3 define "pin-points" as "colonies that are just visible to the naked eye and appear small under a hand lens." This description may fit one or many types of colonies. Fay :L1 in advising against the unrestricted use of the term pin-points was the first to give definite measurements and descriptions of the colonies. As a result of his work, he divided the colonies into two types, describing the type by the shape of the colony, viz.:? type A colony was spindle-shaped, measuring 0.150 to 0.175 mm. in its longest diameter. Type B colony was circular, measuring 0.250 to 0.350 mm. in diameter. Furthermore, he separated the organisms he found into three groups: group 1, organisms resembling Streptococcus lactis; group 2, chains of 4 to 10 irregular shaped cells, and group 3, long, narrow rods in pairs?one cell being smaller than the other as a daughter cell and measuring 1.95 by 0.70 microns. There seems to be no relationship, however, between the two types of colonies specified and the above three groups.