The European Sero-Epidemiology Network 2: standardization of assay results for hepatitis B virus

The aim of the European Sero-Epidemiology Network 2 was to coordinate and standardize the serological surveillance of vaccine-preventable diseases in Europe. In this study, the standardization of hepatitis B virus (HBV) results is described. The 15 participating national laboratories tested a unique panel of 172 sera established by the Greek reference centre for HBV surface antigen (HBsAg), antibodies to HBsAg (anti-HBs) and/or to the HBV core antigen (anti-HBc) by assay methods of their choice. Country-specific quantitative measurements for anti-HBs and anti-HBc were transformed into common units using standardization equations derived by regressing each country's panel results against the reference centre's results, thus adjusting for interassay and interlaboratory variability. For HBsAg, a qualitative analysis (positive/negative) showed at least 99% agreement with the reference laboratory for all countries. By combining these standardized and qualitative results for the markers mentioned earlier, it was possible to achieve comparable estimates of the proportion of the population susceptible to HBV, vaccinated against HBV, with a past HBV infection, and with a current infection or chronic carrier state. Standardization is a very important tool that allows for international serological comparisons to assess the current vaccination policies and the progress of HBV control in Europe.     

ESEN: a comparison of vaccination programmes - Part three : measles mumps and rubella

Cet article est le dernier d une serie de trois articles portant sur la comparaison, dans huit pays (Danemark, Angleterre et Pays de Galles, Finlande, France, Allemagne, Italie, Suede et Pays-Bas), des programmes vaccinaux et de l impact epidemiologique d     

Evaluation of the rubella surveillance system in Quebec

OBJECTIVE: To evaluate the validity of information in the rubella surveillance system in Quebec. DATA AND METHODS: Cases of rubella in the provincial registry of notifiable diseases, "Maladies à declaration obligatoire" (MADO), from 1994 to 1996 were matched with laboratory-identified cases and with cases in a reference file created from all case investigation records of regional departments of public health for the same period. Sensitivity and the proportion of cases in agreement were calculated. RESULTS: Compared with laboratories, the sensitivity of the provincial registry was 56%. Compared with the reference file, global sensitivity (confirmed cases plus clinical cases) was 58% and the positive predictive value was 50%. Of the 356 cases reported to regional public health departments, 65% were classified in the same diagnostic category (confirmed case, clinical case, excluded case) by public health professionals and a group of experts (weighted kappa=0.32). Information on rubella vaccination status was missing in 25% of cases in the MADO file for rubella. CONCLUSIONS: Notification of positive results for immunoglobulin M antibodies and viral cultures should be required of all laboratories. Uniform procedures should be adopted and applied for the validation of cases that are reported to regional departments of public health. In the context of the rarefaction of rubella, any immunoglobulin M-positive result should be interpreted using all available epidemiological information.     

Integrating measles and rubella surveillance: the experience in the Caribbean

In 1988, the Ministers of Health in the Caribbean Community resolved to eliminate cases of indigenous measles. Specific performance indicators were developed to regularly monitor the program. In 1998, selected countries in the Caribbean elected to accelerate rubella control. As a first step, surveillance for both measles and rubella was integrated, using the measles eradication system as a template. Between 1995 and 2000, 98%-99% of the surveillance sites reported weekly. During that time, the number of suspected measles and rubella cases that were disqualified by laboratory testing remained relatively constant at 94%-99%; however, the indicator for suspected cases investigated within 48 h improved from 89% in 1996 to 95% in 2000. This integrated surveillance system has thus proven to be as effective and efficient as the measles surveillance system alone. Limited changes were made to the initial measles system, and the transition was relatively smooth. The integrated system has been crucial to the control of rubella and for the maintenance of measles elimination in the Caribbean.     

Enhanced laboratory surveillance for the elimination of rubella and congenital rubella syndrome in the Americas

One of the reasons the 1997 Technical Advisory Group on Vaccine-Preventable Diseases recommended acceleration of rubella and congenital rubella syndrome (CRS) prevention efforts was the fact that the enhanced measles surveillance system in the Americas found that 25% of reported measles cases were laboratory-confirmed rubella cases. Until 1997, the laboratory network primarily focused on measles diagnosis. Since 1999, due to the accelerated rubella control and CRS prevention strategy, laboratories have supported the regional measles, rubella, and CRS elimination goals. The measles-rubella laboratory network established in the Americas provides timely confirmation or rejection of suspected measles and rubella cases, and determination of the genotypic characteristics of circulating virus strains, critical information for the programs. A quality assurance process has ensured high-quality performance of procedures in the network. Challenges are occurring, but the measles-rubella laboratory network continues to adapt as the requirements of the program change, demonstrating the high quality of the laboratories in support of public health activities and elimination goals.     

Preventing congenital rubella infection in the European Region of WHO: 2010 target

The World Health Organisation (WHO) Regional Office for Europe has recently published a strategic plan and surveillance guidelines for measles and congenital rubella infection. The strategy prioritizes measles control activities but encourages the introduction of rubella vaccine when measles vaccine coverage has reached >90 %; although, many western European countries with suboptimal measles vaccine coverage are already using the combined measles, mumps and rubella (MMR) vaccine. Women in these countries may have an especially high risk of having an infant with congenital rubella syndrome. WHO is seeking to improve the surveillance for rubella and congenital rubella syndrome as a means to obtain better information on the burden of these diseases and engage policy decision makers in the need to support the WHO European Region's strategies for rubella.     

Lessons learned from integrated surveillance of measles and rubella in the Caribbean

The Caribbean subregion was one of the first areas to successfully integrate measles and rubella surveillance, and it can serve as an example to other subregions on how to achieve similar success. The integrated surveillance system, established through strong political commitment by Caribbean countries, is coordinated by the Caribbean Epidemiology Centre (CAREC). The system, which became operational in January 2000, is designed to detect and investigate patients with fever and rash illness, and also test a blood specimen from each case investigated. During over 9 years of operation, 3733 cases were reported and investigated. Laboratory tests identified 2 imported cases of measles, 27 cases of rubella, 309 cases of dengue, and 260 cases of human herpesvirus 6 (HHV-6) infection. The lessons learned from the success of this integrated system indicate that the following factors are critical: strong political commitment, strong technical oversight from all levels within the health-care system, the use of proven tools or systems and technology for data collection and analysis, integration with other surveillance activities, continuing training, and continuing review and evaluation.     

上海市猪感染流行性乙型脑炎病毒的血清学监测

流行性乙型脑炎 (以下简称乙脑 )是一种人兽共患的急性病毒性传染病 ,猪是乙脑最重要的传染源和乙脑病毒传播的主要宿主 ,在乙脑的流行环节上起重要作用〔1〕。因此 ,对猪感染乙脑病毒时间的血清学监测可反映乙脑病毒在自然界的循环情况 ,预测人群乙脑的流行趋势。猪感染乙脑病毒的情况可通过乙脑抗体阳转时间和乙脑抗体阳转率来反映。上海市分别在 1975年 4～ 10月、1985年 6月～ 1986年 8月和 1987年 6～ 12月对猪感染乙脑作了血清学监测。间断十几年后 ,我们于 1999年 4～11月对上海市猪感染乙脑的情况进行血清学监测 ,以了解目前乙脑病…     

Trends in Barrett's esophagus diagnosis in Southern Europe: implications for surveillance

The incidence of Barrett's esophagus (BE) and esophageal adenocarcinoma has increased in Western countries in recent decades. The aim of this study is to describe the changes in incidence and prevalence of BE diagnosis, dysplasia, and adenocarcinoma development in BE patients in a South‐European Mediterranean area. Retrospective population‐based analyses of endoscopy and pathology reports from 1976 to 2001 was performed. Data from patients with diagnosis of BE and/or esophageal carcinoma were collected. The study period was divided in four quartiles for statistical calculations; parametric and nonparametric tests were used. A 6.9‐fold increase was found in the diagnosis of long‐segment BE from the first to the fourth quartile, and a 9.3‐fold increase in short‐segment BE from 1995 to 2000, in contrast to a much smaller increase of 1.9‐fold increase in the number of upper gastrointestinal endoscopies. The adjusted incidence of BE diagnosis increased from 0.73 to 9.73 cases/100 000 (first to fourth quartile, respectively) and the adjusted prevalence from 6.51 to 76.04 cases/100 000 (1985–2001). The incidence of dysplasia was 2.13% per year (95% confidence interval: 0.05–11.3%) ? 1.78% for low‐grade dysplasia and 0.36% for high‐grade dysplasia – giving a total incidence of 1 per 47 patient‐years. The incidence of adenocarcinoma during follow‐up was 0.48% per year (95% confidence interval: 0.006–2.62%), for an incidence of 1 per 210 patient‐years. Nineteen patients with BE (14 long‐segment BE, 5 short‐segment BE) were diagnosed with esophageal adenocarcinoma, with eight being diagnosed during endoscopic surveillance. Only 14 (8%) adenocarcinoma patients diagnosed during the study period had a history of BE. BE diagnosis has dramatically increased over recent decades in our population, unrelated to an increase in endoscopies. Progression to low‐grade dysplasia and adenocarcinoma is rare. Surveillance may have a low impact on the survival of adenocarcinoma patients in Southern Europe.     

Sentinel surveillance of influenza in Europe 1997-1998

The circulation of influenza virus is associated with increased consultation rates with general practitioners (GPs), increased hospital admissions, and excess deaths and has to be considered in health care planning. In western Europe, influenza viruses no     

Banking of cryopreserved heart valves in Europe: assessment of a 10-year operation in the European Homograft Bank (EHB)

BACKGROUND AND AIM OF THE STUDY: The preparation, banking and distribution of cryopreserved heart valves has been carried out at the European Homograft Bank (EHB) in Brussels without interruption since January 1989. We present an assessment of the Bank's activities during this 10-year period. METHODS: Heart valve donors aged <62 years form three categories: multiorgan donors with non-transplantable hearts; recipients of cardiac transplantation; and non-beating heart cadavers with a warm ischemia time of less than 6 h. Past history and biology are checked for transmissible diseases. Dissection, incubation in antibiotics and cryopreservation in 10% dimethylsulfoxide with storage in liquid nitrogen vapors (about -150 degrees C), and quality control are according to the standards of the Belgian Ministry of Health. Cryopreserved valves are shipped to the implantation centers in a dry shipper at about -150 degrees C. RESULTS: Between January 30th 1989 and December 31st 1998, 1,817 non-transplantable hearts and 12 excised semilunar valves were obtained. In total, 2,077 valves (1,032 pulmonary, 931 aortic and 13 mitral) were decontaminated, cryopreserved and stored in liquid nitrogen vapor (six more valves were refrigerated). In total, 1,515 valves were discarded at different stages of the protocol, the main causes of rejection being significant macroscopic lesions (68.2% aortic and 26.67% pulmonary). Inadequate excision at procurement (10.37% pulmonary), persistent contamination after antibiotics (5.6%) and positive serology for hepatitis B and C and Q fever (5.4%) were other frequent causes for rejection. Among the 2,117 accepted valves, 1,398 were graded first and 719 second choice, mainly on the basis of morphology. In total, 2,090 cryopreserved valves and one refrigerated valve were implanted in 39 institutions between May 1989 and December 1998. Of requests, 10.02% could not be satisfied. In total, 967 pulmonary valves were implanted in the right ventricular outflow tract (RVOT); 424 during a Ross procedure, and 76 in the left ventricular outflow tract (LVOT). Of the aortic valves, 732 were implanted in the LVOT and 266 in the RVOT. Mitral homografts were used for tricuspid valve replacement in two cases, and in the mitral position in seven. Complications at distribution and thawing included 10 bag ruptures and 16 transversal conduit wall fractures. Of the valves shipped, 317 (13.16%) were not used and were returned safely in the dry shipper. Comparison of distribution rates in the first 5.5 and last 4.5 years of EHB activity shows: (i) a significant increase in pulmonary valve implantations in the RVOT (from 71.95% to 81.95%); and (ii) a marked increase (265%) in pulmonary homograft implantations as part of a Ross operation, and a significant decrease (28%) in aortic homograft implantation in the LVOT. CONCLUSION: While macroscopic lesions of procured aortic valves remain the most frequent and unavoidable cause of homograft rejection during quality control, the high percentage of inadequate surgical heart valve excision should be corrected. The rates of bacterial contamination and positive serology seem acceptable. Storage and shipping of cryopreserved homografts in liquid nitrogen vapor permits them to be spared very efficiently. The increasing use of pulmonary valves for RVOT reconstruction either in congenital heart disease or as part of the Ross procedure compensates for the limited availability of good quality aortic valves.     

Feasibility of surveillance resistance to antituberculosis drugs :Europe, 1997

Between 28% and 100% of isolates from ten countries from the EuroTB network in 1997 were reported with data on antituberculosis drug susceptibility. Drug resistance was commoner among foreign-born patients and in general among patients who had been treate     

National nosocomial infections surveillance system (NNIS): description of surveillance methods.

The National Nosocomial Infections Surveillance System (NNIS) is an ongoing collaborative surveillance system sponsored by the Centers for Disease Control (CDC) to obtain national data on nosocomial infections. The CDC uses the data that are reported voluntarily by participating hospitals to estimate the magnitude of the nosocomial infection problem in the United States and to monitor trends in infections and risk factors. Hospitals collect data by prospectively monitoring specific groups of patients for infections with the use of protocols called surveillance components. The surveillance components used by the NNIS are hospitalwide, intensive care unit, high-risk nursery, and surgical patient. Detailed information including demographic characteristics, infections and related risk factors, pathogens and their antimicrobial susceptibilities, and outcome, is collected on each infected patient. Data on risk factors in the population of patients being monitored are also collected; these permit the calculation of risk-specific rates. An infection risk index, which includes the traditional wound class, is being evaluated as a predictor of the likelihood that an infection will develop after an operation. A major goal of the NNIS is to use surveillance data to develop and evaluate strategies to prevent and control nosocomial infections. The data collected with the use of the surveillance components permit the calculation of risk-specific infection rates, which can be used by individual hospitals as well as national health-care planners to set priorities for their infection control programs and to evaluate the effectiveness of their efforts. The NNIS will continue to evolve in finding more effective and efficient ways to assess the influence of patient risk and changes in the financing of health care on the infection rate.     

Measles and rubella in the World Health Organization European region: diversity creates challenges

Since 1984, the World Health Organization (WHO) European Region has had targets for reducing the burden of a number of communicable diseases. While some countries have already met the targets for interrupting indigenous measles transmission and for reducing the incidence of congenital rubella syndrome to <1 case per 100,000 births, most have not. The cultural and economic diversity of the region present a number of challenges that must be overcome before the regional targets are met. These include social factors, political will, economic costs associated with supplementary campaigns, and more effective communication with health professionals and the public on the benefits and risks associated with immunization. Most WHO European Region member states are expected to use combined measles-mumps-rubella vaccine within the next 5 years. Consultation within the region is occurring on a strategic plan to meet the targets by 2010.