Chemoprophylaxis and vaccination in preventing subsequent cases of meningococcal disease in household contacts of a case of meningococcal disease: a systematic review.

Household contacts of an index case of invasive meningococcal disease (IMD) are at increased risk of acquiring disease. In revising WHO guidance on IMD in sub-Saharan Africa, a systematic review was undertaken to assess the effect of chemoprophylaxis and of vaccination in preventing subsequent cases of IMD in household contacts following an index case. A literature search for systematic reviews identified a single suitable review on chemoprophylaxis in 2004 (three studies meta-analysed). A search for primary research papers published since 2004 on chemoprophylaxis and without a date limit on vaccination was therefore undertaken. There were 2381 studies identified of which two additional studies met the inclusion criteria. The summary risk ratio for chemoprophylaxis vs. no chemoprophylaxis (four studies) in the 30-day period after a case was 0·16 [95% confidence interval (CI) 0·04-0·64, P = 0·008]; the number needed to treat to prevent one subsequent case was 200 (95% CI 111-1000). A single quasi-randomized trial assessed the role of vaccination. The risk ratio for vaccination vs. no vaccination at 30 days was 0·11 (95% CI 0·01-2·07, P = 0·14). The results support the use of chemoprophylaxis to prevent subsequent cases of IMD in household contacts of a case. Conclusions about the use of vaccination could not be drawn.

Use of hub cutters and the volume of sharp waste and occurrence of needle-stick injuries during 2011 mass immunization campaigns against yellow fever in Ghana: a cohort study.

BACKGROUND: Current WHO best infection control practices for injections do not address the use of hub cutters due to insufficient evidence on safety and efficacy. OBJECTIVE: To assess the impact of the use of hub cutters on 1) the frequency of needle-stick injuries (NSIs) and other blood exposures among workers and 2) the volume of sharps waste in a mass vaccination campaign setting. METHODS: During yellow fever vaccination in Ghana, we conducted a cohort study on the use of hub cutters. We compared two groups---one group using hub cutters and a control group---for the occurrences of NSIs and the volume of sharp waste produced. RESULTS: In the control arm, vaccinators used 284 482 syringes in 825 vaccination sessions. In the group using hub cutter, vaccinators used 397 079 syringes in 1599 sessions. Among vaccinators, the rate of NSI was not significantly (p=0.14) different between the hub cutter users (0.15/10 000 syringes) and the control group (0.04/10 000). Factors such as workload, lack of organization and pressure seemed to have influence the occurrence of NSIs. With all the limitations of the work, the volume of sharp waste per 10 000 syringes was 0.24 m(3) in the hub cutter users and 0.41 m(3) in the control group---a reduction of 41.2%. Vaccinators found hub cutters easy to use and safe. Use of hub cutter was not associated with increased duration of work. CONCLUSION: The use of hub cutters did not increase the risk of NSIs. More training is needed to facilitate its implementation in mass campaign setting.

Clustered lot quality assurance sampling: a tool to monitor immunization coverage rapidly during a national yellow fever and polio vaccination campaign in Cameroon, May 2009.

We used the clustered lot quality assurance sampling (clustered-LQAS) technique to identify districts with low immunization coverage and guide mop-up actions during the last 4 days of a combined oral polio vaccine (OPV) and yellow fever (YF) vaccination campaign conducted in Cameroon in May 2009. We monitored 17 pre-selected districts at risk for low coverage. We designed LQAS plans to reject districts with YF vaccination coverage <90% and with OPV coverage <95%. In each lot the sample size was 50 (five clusters of 10) with decision values of 3 for assessing OPV and 7 for YF coverage. We 'rejected' 10 districts for low YF coverage and 14 for low OPV coverage. Hence we recommended a 2-day extension of the campaign. Clustered-LQAS proved to be useful in guiding the campaign vaccination strategy before the completion of the operations.

Clustered lot quality assurance sampling: a pragmatic tool for timely assessment of vaccination coverage.

OBJECTIVES: To evaluate oral poliovirus vaccine (OPV) coverage of the November 2009 round in five Northern Nigeria states with ongoing wild poliovirus transmission using clustered lot quality assurance sampling (CLQAS). METHODS: We selected four local government areas in each pre-selected state and sampled six clusters of 10 children in each Local Government Area, defined as the lot area. We used three decision thresholds to classify OPV coverage: 75-90%, 55-70% and 35-50%. A full lot was completed, but we also assessed in retrospect the potential time-saving benefits of stopping sampling when a lot had been classified. RESULTS: We accepted two local government areas (LGAs) with vaccination coverage above 75%. Of the remaining 18 rejected LGAs, 11 also failed to reach 70% coverage, of which four also failed to reach 50%. The average time taken to complete a lot was 10 h. By stopping sampling when a decision was reached, we could have classified lots in 5.3, 7.7 and 7.3 h on average at the 90%, 70% and 50% coverage targets, respectively. CONCLUSIONS: Clustered lot quality assurance sampling was feasible and useful to estimate OPV coverage in Northern Nigeria. The multi-threshold approach provided useful information on the variation of IPD vaccination coverage. CLQAS is a very timely tool, allowing corrective actions to be directly taken in insufficiently covered areas.

The immunization data quality audit: verifying the quality and consistency of immunization monitoring systems.

OBJECTIVE: To evaluate the consistency and quality of immunization monitoring systems in 27 countries during 2002-03 using standardized data quality audits (DQAs) that had been launched within the framework of the Global Alliance for Vaccines and Immunization. METHODS: The consistency of reporting systems was estimated by determining the proportion of third doses of diphtheria-tetanuspertussis (DTP-3) vaccine reported as being administered that could be verified by written documentation at health facilities and districts. The quality of monitoring systems was measured using quality indices for different components of the monitoring systems. These indices were applied to each level of the health service (health unit, district and national). FINDINGS: The proportion of verified DTP-3 doses was lower than 85% in 16 countries. Difficulties in verifying the doses administered often arose at the peripheral level of the health service, usually as the result of discrepancies in information between health units and their corresponding districts or because completed recording forms were not available from health units. All countries had weaknesses in their monitoring systems; these included the inconsistent use of monitoring charts; inadequate monitoring of vaccine stocks, injection supplies and adverse events; unsafe computer practices; and poor monitoring of completeness and timeliness of reporting. CONCLUSION: Inconsistencies in immunization data occur in many countries, hampering their ability to manage their immunization programmes. Countries should use these findings to strengthen monitoring systems so that data can reliably guide programme activities. The DQA is an innovative tool that provides a way to independently assess the quality of immunization monitoring systems at all levels of a health service and serves as a point of entry to make improvements. It provides a useful example for other global health initiatives.

An outbreak of Legionnaire's disease among visitors to a fair in Belgium in 1999.

This paper describes an outbreak of Legionnaire's disease at Kapellen in Belgium among visitors of the annual fair. The investigation started on 13th November 1999 after a respiratory physician notified the health authorities of the province of Antwerp of presumptive cases of legionellosis. The annual commercial fair at Kapellen, a small town in northern Belgium, was held 10 days previously and attracted 50,000 visitors. Stand employees (professionals or volunteers), technical staff of the hall and visitors at the fair were affected cases. An exploratory case-control study was conducted to trace the source of the epidemic. To complete the inventory study and to evaluate other risk factors, a cohort study of exhibitors and staff was conducted. Ninety-three people met the case definition, 41 of whom were considered as confirmed, 14 as presumptive cases and 38 as possible/clinical cases. Five people died. Further testing at the reference laboratory confirmed all strains to be Legionella pneumophila serogroup 1. The sensitivity for culture was low (29.2%), and sensitivity for seroconversion was high (90.9%). For urinary antigen test, a sensitivity with Biotest EIA of 65.6% was found, and the sensitivity of polymerase chain reaction (PCR) was 85.7%. In all cases, the individual had visited the fair. Those individuals working in the central areas of the tent, near the aerosol-producing devices, were at higher risk of disease. Legionella was detected by PCR on swabs of the surfaces of the whirlpool. Although not fully proven, an aerosol-producing device was the most probable source of the outbreak.

National epidemiologic surveys of Enterobacter aerogenes in Belgian hospitals from 1996 to 1998.

Two national surveys were conducted to describe the incidence and prevalence of Enterobacter aerogenes in 21 Belgian hospitals in 1996 and 1997 and to characterize the genotypic diversity and the antimicrobial resistance profiles of clinical strains of E. aerogenes isolated from hospitalized patients in Belgium in 1997 and 1998. Twenty-nine hospitals collected 10 isolates of E. aerogenes, which were typed by arbitrarily primed PCR (AP-PCR) using two primers and pulsed-field gel electrophoresis. MICs of 10 antimicrobial agents were determined by the agar dilution method. Beta-lactamases were detected by the double-disk diffusion test and characterized by isoelectric point. The median incidence of E. aerogenes colonization or infection increased from 3.3 per 1,000 admissions in 1996 to 4.2 per 1000 admissions in the first half of 1997 (P < 0.01). E. aerogenes strains (n = 260) clustered in 25 AP-PCR types. Two major types, BE1 and BE2, included 36 and 38% of strains and were found in 21 and 25 hospitals, respectively. The BE1 type was indistinguishable from a previously described epidemic strain in France. Half of the strains produced an extended-spectrum beta-lactamase, either TEM-24 (in 86% of the strains) or TEM-3 (in 14% of the strains). Over 75% of the isolates were resistant to ceftazidime, piperacillin-tazobactam, and ciprofloxacin. Over 90% of the strains were susceptible to cefepime, carbapenems, and aminoglycosides. In conclusion, these data suggest a nationwide dissemination of two epidemic multiresistant E. aerogenes strains in Belgian hospitals. TEM-24 beta-lactamase was frequently harbored by one of these epidemic strains, which appeared to be genotypically related to a TEM-24-producing epidemic strain from France, suggesting international dissemination.

Potential susceptible individuals to poliomyelitis in Austria.

This report presents the results of a vaccine coverage survey that was performed in the Tyrol (Austria) in 1997. The major finding is that pockets of children susceptible to poliomyelitis currently exist in the area, because of delayed immunisation. The cause for the delay is the practice of interrupting oral poliomyelitis vaccine (OPV) administration during summer months.

Evaluation of a transit first-aid station providing emergency care to former Yugoslavian war victims evacuated in Ancona, Italy.

BACKGROUND: A first-aid station was implemented in Falconara Marittima airport (Ancona, Italy). It provided medical emergency care to war victims evacuated from former Yugoslavia in transit for further treatment. MATERIALS AND METHODS: A descriptive analysis of the displaced population arriving at the first-aid station was performed using three independent datasets for administrative information, of which one included medical information. The implemented resources were also evaluated. RESULTS: From August 1993 to March 1995, 2272 displaced persons were registered at the first-aid station, out of which 54.2% were accompanying family members. Among those needing medical intervention (45.8% of total), most frequent diagnoses were traumatisms and burns (59.8%), neoplasms (15.6%), and congenital malformations (13.2%). The medical care provided at the first-aid station was most often basic: a medical examination alone was performed on 77.0% of the patients, and a minor dressing on 17.3%. Median length of stay was 1 day. Patients were sent to 30 different countries and 8% were forwarded to the local regional hospital. Deployed logistical resources exceeded by far actual needs but a lack of psychological assistance was observed, mainly for children. The agencies involved did not coordinate data sharing and follow-up information. CONCLUSIONS: The medical assistance to the war victims was efficient regarding provided care and timeliness. Effectiveness of such a programme could be improved by a better coordination between partners, allowing more adequate logistics according to appropriate epidemiological information.

An outbreak of Norwalk like virus gastroenteritis in a nursing home in Rotterdam.

Sixty-two per cent of elderly and disabled residents of a Dutch nursing home (74/120) and 32% of staff (33/102) became ill in an outbreak of Norwalk-like viral gastroenteritis. The outbreak spread from person to person was supported by temporal clustering

An outbreak of legionnaire s disease among visitors to a fair in Belgium, 1999.

Ninety-three cases of legionnaires disease (43 confirmed, 12 presumptive, and 38 possible/ clinical) were identified in an outbreak associated with a trade fair in Kapellen, Belgium in November 1999. Five cases died. Epidemiological investigation showed

A Campylobacter coli foodborne outbreak in Belgium.

In May 1995, the Scientific Institute of Public Health was informed of an outbreak of gastrointestinal illness in a congregational school in the Brussels area. The field investigation identified 24 cases with mild to severe gastrointestinal and general symptoms of acute bacterial enterocolitis. Campylobacter coli was detected in the stools of 5 patients. A retrospective cohort study suggested that a mixed salad (containing ham and feta cheese) was the probable source of infection, but the route of contamination remained unknown. The rapid investigation of such episodes of collective foodborne infections is essential for the implementation of adequate control measures.

Methicillin-resistant Staphylococcus aureus and antimicrobial use in Belgian hospitals.

OBJECTIVE: To investigate relationships between the incidence of methicillin-resistant Staphylococcus aureus (MRSA) and the use of different classes of antimicrobials in Belgian hospitals. DESIGN: Using Pearson correlation coefficients, the number of new nosocomial MRSA-colonized or -infected patients in the second half of 1994 and the first half of 1995 reported by the national MRSA surveillance program was compared with use of various antimicrobial classes as reported by the National Institute for Sickness and Disability Insurance. Relationships between different classes of antimicrobials were evaluated in a correlation matrix. MRSA incidence, antimicrobial use, and potential confounding factors were included in a multiple linear regression analysis. SETTING: 50 hospitals in Belgium. RESULTS: The use of a number of different classes of antimicrobials was interrelated. In the multivariate analysis, the incidence of nosocomial MRSA increased with increasing use of ceftazidime and cefsulodin (P=.0003), amoxicillin with clavulanic acid (P=.02), and quinolones (P=.005). No association was found between MRSA incidence and total antimicrobial use. CONCLUSIONS: The relationships between antimicrobial use and MRSA are complex. Interventions aimed at promoting more rational prescribing patterns should be supported by adequate experimental and epidemiological evidence. Advice for preventing and controlling MRSA has focused mainly on hygienic measures and precautions to avoid cross-transmission; the role of relieving antimicrobial pressure needs to be clarified.

Emergence of Enterobacter aerogenes as a major antibiotic-resistant nosocomial pathogen in Belgian hospitals.

OBJECTIVE: To study the epidemiology of Enterobacter aerogenes infections in Belgian hospitals and determine whether recent trends show an increase in incidence of E. aerogenes infections and antimicrobial resistance. METHODS: Data from the bloodstream infection component of the National Surveillance of Hospital Infections (October 1992 to September 1996 data in 45 hospitals) and from a retrospective study on E. aerogenes clinical isolates (1994 and 1995 data in 41 hospitals) were analyzed. RESULTS: E. aerogenes was recovered from clinical specimens with a mean incidence of 4.6 isolates per 10 000 patient-days and caused 0.20 bloodstream infections per 10 000 patient-days during the surveyed periods, respectively. Both rates increased significantly throughout the years. The proportion of E aerogenes within the Enterobacter genus was 35.4% in clinical isolates and 41.2% in bloodstream infections. Both proportions significantly increased over time. Incidence was not statistically different by hospital size but showed major differences between geographic regions. Resistance rates to third-generation cephalosporins and fluoroquinolones increased, and imipenem resistance emerged in several hospitals. CONCLUSIONS: This report provides evidence of an increase in E. aerogenes infections in Belgian hospitals and documents an increase in antimicrobial resistance of E. aerogenes strains. These figures provide a baseline for further surveillance data.

Epidemiology of nosocomial bloodstream infections in Belgium, 1992-1996.

The main results of the bloodstream infection (BSI) component of the Belgian National Programme for the Surveillance of Hospital Infections (NSIH project) are reported. From October 1992 to September 1996, 117 hospitals (59.1% of Belgian acute-care institutions) reported 13678 nosocomial BSIs. The incidence was 7.05 BSI episodes per 10000 patient-days. The incidence of BSI increased with hospital size and over time. Bloodstream infections were secondary to an infectious body site in 40.3% of the episodes, catheter-related in 23.5%, and of unknown origin in 36.2%. The associated in-hospital mortality was 31.4% and was highest in BSIs secondary to a respiratory tract infection (49.3%). In intensive care units, the incidence of BSI was 38.5 per 10000 patient-days. Coagulase-negative staphylococci were the most prevalent microorganisms (22%), followed by Staphylococcus aureus (14.1%) and Escherichia coli (13.5%). In catheter-related BSIs, these proportions were 41.9%, 18.8%, and 2.3%, respectively. The proportion of polymicrobial episodes was 9.9%. Methicillin resistance in Staphylococcus aureus was 22.3%. With its high participation rate, the NSIH project has characterized the epidemiology of nosocomial BSIs in Belgium during the period studied.

Surgical prophylaxis in Belgian hospitals: estimate of costs and potential savings.

Between 1991 and 1995 the Belgian National Program for Surveillance of Hospital Infections (NSIH) collected data on perioperative antibiotic prophylaxis in 72 acute care hospitals. From the costs of prophylactic antibiotics for six categories of surgical procedure and from discharge summaries for hospitalization episodes nationwide, annual drug costs were estimated for 73% of Belgian surgical activity. Costs of antibiotics used in these surgical activities were estimated at 386-410 million Belgian francs (Bf) per year (US$12.1-12.9 million). After agreeing recommendations for best practice, the hypothetical costs of 'optimal' antimicrobial prophylaxis were calculated for the same selection of surgical procedures. It was calculated that savings of at least 194 million Bf (US$6.1 million) could be made if recommendations were followed closely. Only the costs borne by the National Health Insurance Institute for reimbursement of the dispensed drugs were considered in this study. Other direct costs, such as those related to drug storage, dispensing and administration, were not included.

Descriptive epidemiology of exanthems in the Rotterdam region January 1997 to June 1998.

The European Advisory Group on Immunisation has recommended that measles should be eliminated from Europe by the year 2007, a target accepted by National Immunisation Programme Managers for the World Health Organization (WHO) European Region countries. I

Prevention of transmission of tuberculosis in hospitals; a survey of practices in Belgium, 1995.

In July 1995, a questionnaire survey was made of nosocomial tuberculosis (TB) prevention practices in Belgian hospitals. Of 122 respondents (response rate: 64%), 93% had hospitalized at least one TB patient, and 11% at least one multi-resistant TB case, during 1994. Effective prevention measures were not uniformly applied: only 96% isolated contagious TB patients, and only 84% isolated patients suspected of contagious T.B. In six hospitals, TB patients and those with human immunodeficiency virus (HIV) were mixed. Wearing of masks by personnel entering a TB patient's room was routine in 96%, but in only 24% of these was the mask adequate for filtering 1 micron particles. Moreover, some centres made use of seemingly unnecessary measures, for example routine use of disposable crockery (50%) and enhanced room cleaning (66%). Expensive prevention measures were rarely applied: UV lamps in 12%; HEPA filters in air conditioning in 2%. Tuberculin skin testing at some stage of employment, was routinely performed by 82% of respondents, but varied according to the type of personnel: doctors and temporary staff were significantly under-assessed. Lowest conversion rates among staff were observed in hospital with the least TB admissions but high rates were observed in hospitals of all sizes. The risk of acquiring TB in Belgian hospitals exists and precautions taken to prevent transmission are not sufficient. The situation could be improved by following national guidelines and a general adoption of proven effective practices, and by abandoning expensive and ineffective measures.