A risk-based restaurant inspection system in Los Angeles County.

The majority of local health departments perform routine restaurant inspections. In Los Angeles County (LAC), California, approximately $10 million/year is spent on restaurant inspections. However, data are limited as to whether or not certain characteristics of restaurants make them more likely to be associated with foodborne incident reports. We used data from the LAC Environmental Health Management Information System (EHMIS), which records the results of all routine restaurant inspections as well as data regarding all consumer-generated foodborne incidents that led to a special restaurant inspection by a sanitarian (investigated foodborne incidents [IFBIs]). We analyzed a cohort of 10,267 restaurants inspected from 1 July 1997 to 15 November 1997. We defined a "case restaurant" as any restaurant with a routine inspection from 1 July 1997 to 15 November 1997 and a subsequent IFBI from 1 July 1997 to 30 June 1998. Noncase restaurants did not have an IFBI from I July 1997 to 30 June 1998. We looked for specific characteristics of restaurants that might be associated with the restaurant subsequently having an IFBI, including the size of restaurant (assessed by number of seats), any previous IFBIs, the overall inspection score, and a set of 38 violation codes. We identified 158 case restaurants and 10,109 noncase restaurants. In univariate analysis, middle-sized restaurants (61 to 150 seats; n = 1,681) were 2.8 times (95% confidence interval [CI] = 2.0 to 4.0) and large restaurants (>150 seats; n = 621) were 4.6 times (95% CI = 3.0 to 7.0) more likely than small restaurants (< or =60 seats; n = 7,965) to become case restaurants. In addition, the likelihood of a restaurant becoming a case restaurant increased as the number of IFBIs in the prior year increased (chi2 for linear trend, P value = 0.0005). Other factors significantly associated with the occurrence of an IFBI included a lower overall inspection score, the incorrect storage of food, the reuse of food, the lack of employee hand washing, the lack of thermometers, and the presence of any food protection violation. In multivariate analysis, the size of restaurant, the incorrect storage of food, the reuse of food, and the presence of any food protection violation remained significant predictors for becoming a case restaurant. Our data suggest that routine restaurant inspections should concentrate on those establishments that have a large seating capacity or a poor inspection history. Evaluation of inspection data bases in individual local health departments and translation of those findings into inspection guidelines could lead to an increased efficiency and perhaps cost-effectiveness of local inspection programs.

EARSS activities and results: update.

(And with EARSS participants) The latest EARSS results (1990-2000) suggest that the rates of methicillin resistant S. aureus and Penicillin Non Susceptible S. pneumoniae are higher in southern European countries than in the North. Young children, followed by elderly people are the most at risk for an infection by PNSP. The risk to be infected by methicillin resistant S. aureus increases with age, patients hospitalised in intensive care units being more exposed to that risk.

[International surveillance of antimicrobial resistance in Europe: now we also need to monitor antibiotic use]. / La surveillance internationale de la résistance aux antibiotiques en Europe: l'heure est a la surveillance de l'utilisation des antibiotiques.

With travel and trade within the European Union (EU) increasing over the years, the risk of dissemination of (resistant) pathogens grows. Many studies have shown that there is a growing problem with antimicrobial resistance. For example, methicillin resistant Staphylococcus aureus (MRSA) was initially largely a problem of hospitals, but it is now increasingly reported as a community acquired infection. Certain strains have been shown to spread between European countries. Antimicrobial resistance may result in prolonged hospital stay, higher costs, and higher morbidity or even mortality.

Epidemiologic relation between HIV and invasive pneumococcal disease in San Francisco County, California.

BACKGROUND: Patients with AIDS have a high incidence of invasive pneumococcal disease, but no population-based data are available on secular trends or rates of this disease in specific demographic groups. OBJECTIVE: To compare clinical characteristics, rates, and trends of pneumococcal disease in HIV-infected and non-HIV-infected persons. DESIGN: Population-based laboratory surveillance and chart review. SETTING: All of the 13 microbiology laboratories in San Francisco County, California. PATIENTS: Persons who had a sterile site culture that was positive for Streptococcus pneumoniae between October 1994 and June 1997. MEASUREMENTS: Stratified incidence rates and adjusted rate ratios, serotyping of isolates, and comparison of secular trends and rates according to census tract by Poisson regression. RESULTS: Persons infected with HIV accounted for 54.2% of 399 patients 18 to 64 years of age who had pneumococcal disease. The incidence of pneumococcal disease per 100 000 person-years was 35.0 cases overall and 802.9 cases in patients with AIDS. Compared with persons who were not known to be HIV-infected, the rate ratio for patients with AIDS was 46:0 (95% CI, 36.0 to 58.9); 55.2% of cases were attributable to HIV. In HIV-infected patients, 82.5% of isolates were serotypes that are included in the pneumococcal polysaccharide vaccine. The incidence of pneumococcal disease in black patients with AIDS (2384.6 cases per 100 000 person-years) was 5.4 times that in nonblack patients with AIDS. Rates by census tract were inversely associated with income (P < 0.001), During the study period, the incidence of pneumococcal disease decreased from 10.6 cases per 1000 person-years to 4.2 cases per 1000 person-years in patients with AIDS (P = 0.004, Poisson regression). CONCLUSIONS: In a community with a high prevalence of HIV infection, much of the burden of pneumococcal disease was attributable to AIDS. High incidence rates were seen in young adults and especially in black persons. Efforts to increase pneumococcal vaccination rates should target HIV-infected adults, particularly those living in poor urban areas.

Strengths and limitations of molecular subtyping in a community outbreak of Legionnaires' disease.

An epidemiological and microbiological investigation of a cluster of eight cases of Legionnaires' disease in Los Angeles County in November 1997 yielded conflicting results. The epidemiological part of the investigation implicated one of several mobile cooling towers used by a film studio in the centre of the outbreak area. However, water sampled from these cooling towers contained L. pneumophila serogroup 1 of another subtype than the strain that was recovered from case-patients in the outbreak. Samples from two cooling towers located downwind from all of the case-patients contained a Legionella strain that was indistinguishable from the outbreak strain by four subtyping techniques (AP-PCR, PFGE, MAb, and MLEE). It is unlikely that these cooling towers were the source of infection for all the case-patients, and they were not associated with risk of disease in the case-control study. The outbreak strain also was not distinguishable, by three subtyping techniques (AP-PCR, PFGE, and MAb), from a L. pneumophila strain that had caused an outbreak in Providence, RI, in 1993. Laboratory cross-contamination was unlikely because the initial subtyping was done in different laboratories. In this investigation, microbiology was helpful for distinguishing the outbreak cluster from unrelated cases of Legionnaires' disease occurring elsewhere. However, multiple subtyping techniques failed to distinguish environmental sources that were probably not associated with the outbreak. Persons investigating Legionnaires' disease outbreaks should be aware that microbiological subtyping does not always identify a source with absolute certainty.

European Antimicrobial Resistance Surveillance System (EARSS): susceptibility testing of invasive Staphylococcus aureus.

Over 400 laboratories participate in EARSS (European Antimicrobial Resistance Surveillance System) and send data to the National Institute of Public Health and the Environment (RIVM) in The Netherlands. Data on about 14 000 isolates of Staphylococcus aure

Hospital characteristics associated with colonization of water systems by Legionella and risk of nosocomial legionnaires' disease: a cohort study of 15 hospitals.

OBJECTIVE: To investigate an increase in reports of legionnaires' disease by multiple hospitals in San Antonio, Texas, and to study risk factors for nosocomial transmission of legionnaires' disease and determinants for Legionella colonization of hospital hot-water systems. SETTING: The 16 largest hospitals in the cities of San Antonio, Temple, and Austin, Texas. DESIGN: Review of laboratory databases to identify patients with legionnaires' disease in the 3 years prior to the investigation and to determine the number of diagnostic tests for Legionella performed; measurement of hot-water temperature and chlorine concentration and culture of potable water for Legionella. Exact univariate calculations, Poisson regression, and linear regression were used to determine factors associated with water-system colonization and transmission of Legionella. RESULTS: Twelve cases of nosocomial legionnaires' disease were identified; eight of these occurred in 1996. The rise in cases occurred shortly after physicians started requesting Legionella urinary antigen tests. Hospitals that frequently used Legionella urinary antigen tests tended to detect more cases of legionnaires' disease. Legionella was isolated from the water systems of 11 of 12 hospitals in San Antonio; the 12th had just experienced an outbreak of legionnaires' disease and had implemented control measures. Nosocomial legionellosis cases probably occurred in 5 hospitals. The number of nosocomial legionnaires' disease cases in each hospital correlated better with the proportion of water-system sites that tested positive for Legionella (P=.07) than with the concentration of Legionella bacteria in water samples (P=.23). Hospitals in municipalities where the water treatment plant used monochloramine as a residual disinfectant (n=4) and the hospital that had implemented control measures were Legionella-free. The hot-water systems of all other hospitals (n=11) were colonized with Legionella. These were all supplied with municipal drinking water that contained free chlorine as a residual disinfectant. In these contaminated hospitals, the proportion of sites testing positive was inversely correlated with free residual chlorine concentration (P=.01). In all hospitals, hot-water temperatures were too low to inhibit Legionella growth. CONCLUSIONS: The increase in reporting of nosocomial legionnaires' disease was attributable to increased use of urinary antigen tests; prior cases may have gone unrecognized. Risk of legionnaires' disease in hospital patients was better predicted by the proportion of water-system sites testing positive for Legionella than by the measured concentration of Legionella bacteria. Use of monochloramine by municipalities for residual drinking water disinfection may help prevent legionnaires' disease.

Effect of monochloramine disinfection of municipal drinking water on risk of nosocomial Legionnaires' disease.

BACKGROUND: Many Legionella infections are acquired through inhalation or aspiration of drinking water. Although about 25% of municipalities in the USA use monochloramine for disinfection of drinking water, the effect of monochloramine on the occurrence of Legionnaires' disease has never been studied. METHODS: We used a case-control study to compare disinfection methods for drinking water supplied to 32 hospitals that had had outbreaks of Legionnaires' disease with the disinfection method for water supplied to 48 control-hospitals, with control for selected hospital characteristics and water treatment factors. FINDINGS: Hospitals supplied with drinking water containing free chlorine as a residual disinfectant were more likely to have a reported outbreak of Legionnaires' disease than those that used water with monochloramine as a residual disinfectant (odds ratio 10.2 [95% CI 1.4-460]). This result suggests that 90% of outbreaks associated with drinking water might not have occurred if monochloramine had been used instead of free chlorine for residual disinfection (attributable proportion 0.90 [0.29-1.00]). INTERPRETATION: The protective effect of monochloramine against legionella should be confirmed by other studies. Chloramination of drinking water may be a cost-effective method for control of Legionnaires' disease at the municipal level or in individual hospitals, and widespread implementation could prevent thousands of cases.

[Annual epidemics of hepatitis A in four large cities related to holiday travel among immigrant children]. / Jaarlijkse epidemie van hepatitis A in verband gebracht met reisgedrag van kinderen van immigranten in de vier grote steden.

OBJECTIVE: Analysis of the transmission pattern of hepatitis A in relation to ethnicity and travel behaviour in Amsterdam. Utrecht, Rotterdam and The Hague. DESIGN: Descriptive study of notified cases. SETTING: Municipal Health Services of the four major cities in the Netherlands. METHOD: Notification data of hepatitis A in Amsterdam, Utrecht, Rotterdam and The Hague were analysed over the period 1992-1995. Cases were analysed according to age (0-19 years or > 19 years), whether or not they travelled abroad in the period of six weeks before the onset of the first symptoms of disease, and endemicity of hepatitis A in the country of ethnic origin. RESULTS: The strong increase of hepatitis A after the summer holidays could be divided into several smaller epidemics starting with an epidemic among children of Moroccan and Turkish descent who had spent the summer holidays in these countries, among children of the same ethnic background who had not travelled abroad, followed by epidemics among non-travelling children and adults of mainly Dutch descent, respectively. A strong correlation was found in Amsterdam between the incidence in the former two groups and the latter two groups (Pearsons r = 0.68; p = 0.004). CONCLUSION: Children who spent the summer holidays in a hepatitis A endemic country, particularly Morocco and Turkey, appeared to be the main importers of hepatitis A in the four major cities. Active immunization of all children born in the Netherlands of Moroccan and Turkish descent is the most preferable intervention.

More than 10 years of unrecognized nosocomial transmission of legionnaires' disease among transplant patients.

OBJECTIVE: To investigate a cluster of cases of legionnaires' disease among patients at a hospital. SETTING: A university hospital that is a regional transplant center. DESIGN: Retrospective review of microbiology and serology data from the hospital laboratories and prospective surveillance via the radiology department; a case-control study and environmental sampling within the hospital and from nearby cooling towers. RESULTS: Diagnosis of seven cases of legionnaires' disease in the first 9 months of 1996 led to recognition of a nosocomial outbreak that may have begun as early as 1979. Review of charts from 1987 through September 1996 identified 25 culture-confirmed cases of nosocomial or possibly nosocomial legionnaires' disease, including 18 in bone marrow and heart transplant patients. Twelve patients (48%) died. During the first 9 months of 1996, the attack rate was 6% among cardiac and bone marrow transplant patients. For cases that occurred before 1996, intubation was associated with increased risk for disease. High-dose corticosteroid medication was strongly associated with the risk for disease, but other immunosuppressive therapy or cancer chemotherapy was not. Several species and serogroups of Legionella were isolated from numerous sites in the hospital's potable water system. Six of seven available clinical isolates were identical and were indistinguishable from environmental isolates by pulsed-field gel electrophoresis. Initial infection control measures failed to interrupt nosocomial acquisition of infection. After extensive modifications to the water system, closely monitored repeated hyperchlorinations, and reduction of patient exposures to aerosols, transmission was interrupted. No cases have been identified since September 1996. CONCLUSIONS: Legionella can colonize hospital potable water systems for long periods of time, resulting in an ongoing risk for patients, especially those who are immunocompromised. In this hospital, nosocomial transmission possibly occurred for more than 17 years and was interrupted in 1996, after a sudden increase in incidence led to its recognition. Hospitals specializing in the care of immunocompromised patients (eg, transplant centers) should prioritize surveillance for cases of legionnaires' disease. Aggressive control measures can interrupt transmission of this disease successfully.

An outbreak of hepatitis A among homosexual men in Amsterdam, 1991-1993.

BACKGROUND: When in August 1992 it became evident that an outbreak of hepatitis A virus infections (HAV) was taking place in the male homosexual community in Amsterdam a case-control study was conducted to validate the assumption that the outbreak was associated with sexual practices involving oro-anal and digital-anal contact and frequent visits to gay saunas and darkrooms. METHODS: In all, 37 cases reported to the Amsterdam Municipal Health Service (AMHS) in the period December 1991 to March 1993 and 68 anti-HAV negative controls completed an anonymous questionnaire concerning the practice of different sexual techniques and the number of visits to gay saunas and darkrooms in the 2 months preceding the onset of illness or date of interview. Controls were recruited from healthy homosexual men participating in a prospective study on HIV/AIDS conducted by the AMHS. RESULTS: In univariate analysis a statistically significant association was found between visits to gay saunas and darkrooms, the number of visits to these locations (OR = 8.2) and HAV infection. In the logistic regression analysis the association for visits to saunas and darkrooms remained significant (OR = 10) whereas high-risk sexual techniques could not be included in the model. CONCLUSIONS: These results indicate that to prevent future outbreaks of HAV in male homosexuals in Amsterdam there is a need to stress in the 'safe sex' campaigns, directed at the prevention of HIV infection or in additional campaigns, the prevention of other sexually transmitted disease including HAV infection with emphasis on routes associated with certain sexual techniques and on visits to gay saunas and darkrooms.