Irene K. Veldhuijzen

The Relationship between Antimicrobial Use and Antimicrobial Resistance in Europe

In Europe, antimicrobial resistance has been monitored since 1998 by the European Antimicrobial Resistance Surveillance System (EARSS). We examined the relationship between penicillin nonsusceptibility of invasive isolates of Streptococcus pneumoniae (an indicator organism) and antibiotic sales. Information was collected on 1998-99 resistance data for invasive isolates of S. pneumoniae to penicillin, based on surveillance data from EARSS and on outpatient sales during 1997 for beta-lactam antibiotics and macrolides. Our results show that in Europe antimicrobial resistance is correlated with use of beta-lactam antibiotics and macrolides.

Infection with hepatitis B and C virus in Europe: a systematic review of prevalence and cost-effectiveness of screening

BackgroundTreatment for chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infection is improving but not benefiting individuals unaware to be infected. To inform screening policies we assessed (1) the hepatitis B surface antigen (HBsAg) and anti-hepatitis C virus antibody (anti-HCV-Ab) prevalence for 34 European countries; and (2) the cost-effectiveness of screening for chronic HBV and HCV infection.MethodsWe searched peer-reviewed literature for data on HBsAg and anti-HCV-Ab prevalence and cost-effectiveness of screening of the general population and five subgroups, and used data for people who inject drugs (PWID) and blood donors from two European organizations. Of 1759 and 468 papers found in the prevalence and cost-effectiveness searches respectively, we included 124 and 29 papers after assessing their quality. We used decision rules to calculate weighted prevalence estimates by country.ResultsThe HBsAg and anti-HCV-Ab prevalence in the general population ranged from 0.1%-5.6% and 0.4%-5.2% respectively, by country. For PWID, men who have sex with men and migrants, the prevalence of HBsAg and anti-HCV-Ab was higher than the prevalence in the general population in all but 3 countries. There is evidence that HCV screening of PWID and HBsAg screening of pregnant women and migrants is cost-effective.ConclusionThe prevalence of chronic HBV and HCV infection varies widely between European countries. Anti-HCV-Ab screening of PWID and HBsAg screening of pregnant women and migrants have European public health priority. Cost-effectiveness analyses may need to take effect of antiviral treatment on preventing HBV and HCV transmission into account.

Screening and early treatment of migrants for chronic hepatitis B virus infection is cost-effective.

BACKGROUND & AIMS Persons with chronic hepatitis B virus (HBV) infection are at risk of developing cirrhosis and hepatocellular carcinoma. Early detection of chronic HBV infection through screening and treatment of eligible patients has the potential to prevent these sequelae. We assessed the cost-effectiveness in The Netherlands of systematically screening migrants from countries that have high and intermediate HBV infection levels. METHODS Epidemiologic data of the expected numbers of patients with active chronic HBV infection in the target population and information about the costs of a screening program were used in a Markov model and used to determine costs and quality-adjusted life years (QALY) for patients who were and were not treated. RESULTS Compared with the status quo, a 1-time screen for HBV infection can reduce mortality of liver-related diseases by 10%. Using base case estimates, the incremental cost-effectiveness ratio (ICER) of screening, compared with not screening, is euros (euro) 8966 per QALY gained. The ICER ranged from euro7936 to euro11,705 based on univariate sensitivity analysis, varying parameter values of HBV prevalence, participation rate, success in referral, and treatment compliance. Using multivariate sensitivity analysis for treatment effectiveness, the ICER ranged from euro7222 to euro15,694; for disease progression, it ranged from euro5568 to euro60,418. CONCLUSIONS Early detection and treatment of people with HBV infection can have a large impact on liver-related health outcomes. Systematic screening for chronic HBV infection among migrants is likely to be cost-effective, even using low estimates for HBV prevalence, participation, referral, and treatment compliance.

Avian influenza risk perception, Europe and Asia.

During autumn 2005, we conducted 3,436 interviews in European and Asian countries. We found risk perceptions of avian influenza to be at an intermediate level and beliefs of efficacy to be slightly lower. Risk perceptions were higher in Asia than Europe; efficacy beliefs were lower in Europe than Asia.

Perceived threat, risk perception, and efficacy beliefs related to SARS and other (emerging) infectious diseases: Results of an international survey

PurposeTo study the levels of perceived threat, perceived severity, perceived vulnerability, response efficacy, and self-efficacy for severe acute respiratory syndrome (SARS) and eight other diseases in five European and three Asian countries.MethodA computer-assisted phone survey was conducted among 3,436 respondents. The questionnaire focused on perceived threat, vulnerability, severity, response efficacy, and self-efficacy related to SARS and eight other diseases.ResultsPerceived threat of SARS in case of an outbreak in the country was higher than that of other diseases. Perceived vulnerability of SARS was at an intermediate level and perceived severity was high compared to other diseases. Perceived threat for SARS varied between countries in Europe and Asia with a higher perceived severity of SARS in Europe and a higher perceived vulnerability in Asia. Response efficacy and self-efficacy for SARS were higher in Asia compared to Europe. In multiple linear regression analyses, country was strongly associated with perceived threat.ConclusionsThe relatively high perceived threat for SARS indicates that it is seen as a public health risk and offers a basis for communication in case of an outbreak. The strong association between perceived threat and country and different regional patterns require further research.

Population-based Toxoplasma seroprevalence study in The Netherlands

During 1995--1996 a population-based seroprevalence study was conducted in The Netherlands. Risk factors were established for postnatally acquired toxoplasmosis. The results were compared with a study conducted during 1987-1988 in pregnant women in the Southwest of The Netherlands in order to estimate the change in seroprevalence. In total, 7521 sera were tested and the national seroprevalence was 40.5 % (95 % CI 37.5-43.4). Living in the Northwest, having professional contact with animals, living in a moderately urbanized area, being divorced or widowed, being born outside The Netherlands, frequent gardening and owning a cat were independently associated with Toxoplasma seropositivity. Risk factors like eating undercooked meat could not be studied. The seroprevalence among women aged 15-49 years was 10 % lower (35.2 %, 95 % CI 32.9-38.6) in the study of 1995-1996, compared to the Toxoplasma study of 1987--1988 (45.8 %, 95 % CI 45.2-46.3). The steepest rise in seroprevalence still occurred among the subjects aged 25-44 years.

Hepatitis B vaccination targeted at behavioural risk groups in the Netherlands: does it work?

In November 2002, the Netherlands adopted a vaccination program targeted at behavioural risk groups. Between January 2003 and December 2007, 1386 patients acutely infected with HBV were reported. Reported cases declined from 326 in 2003 to 220 in 2007. Sexual intercourse was the most frequently reported mode of transmission (65%), especially among men having sex with men. Genotypes A and D remained predominant. In total, 40,600 participants were fully vaccinated, the overall compliance was 62%, and the estimated overall program coverage was 12% of the at-risk population. With more effort, more susceptibles may be reached, but the program will not be sufficient to substantially reduce HBV in the Netherlands. Therefore, universal vaccination should be considered.

Sources of information and health beliefs related to SARS and avian influenza among Chinese Communities in the United Kingdom and the Netherlands, compared to the general population in these countries

BackgroundEthnic minorities in Europe such as the Chinese may need a special strategy with regard to risk communication about emerging infectious diseases. To engage them in precautionary actions, it is important to know their information sources, knowledge, and health beliefs.PurposeThis study’s purpose is to study the use of information sources, knowledge, and health beliefs related to SARS and avian flu of Chinese people in the UK and The Netherlands, and to make comparisons with the general population in these countries.MethodResults of a self-administered questionnaire among 300 British/Dutch Chinese were compared to data obtained from a computer-assisted phone survey among the general population (n = 800).ResultsBritish/Dutch Chinese got most information about emerging diseases from family and friends, followed by Chinese media and British/Dutch TV. They had less confidence than general groups in their doctor, government agencies, and consumer/patient interest groups. Their knowledge of SARS was high. They had a lower perceived threat than general populations with regard to SARS and avian flu due to a lower perceived severity. They had higher self-efficacy beliefs regarding SARS and avian flu.ConclusionIn case of new outbreaks of SARS/avian flu in China, local authorities in the UK and The Netherlands can best reach Chinese people through informal networks and British/Dutch TV, while trying to improve confidence in information from the government. In communications, the severity of the disease rather than the susceptibility appears to need most attention.

The importance of imported infections in maintaining hepatitis B in The Netherlands.

In The Netherlands, in May 1999 an enhanced surveillance of hepatitis B was begun to collect detailed information of patients with acute hepatitis B virus (HBV) infection. The objective was to gain insight in transmission routes and source of infection of new HBV cases. Through public health services, patients were interviewed on risk factors. It appeared that the majority (59%) acquired the infection through sexual contact; 52% of these by homosexual and 48% by heterosexual contact. In 60% of the heterosexual cases, the source of infection was a partner originating from a hepatitis B-endemic region. Sexual transmission is the most common route of transmission of acute hepatitis B in The Netherlands and introduction of infections from abroad plays a key role in the current epidemiology of HBV. As well as prevention programmes targeted at sexual high-risk groups, prevention efforts should focus more on the heterosexual transmission from HBV carriers.

Viral hepatitis in a multi-ethnic neighborhood in the Netherlands: results of a community-based study in a low prevalence country

OBJECTIVES The prevalence of viral hepatitis varies worldwide. Although the prevalence of hepatitis A virus (HAV) and hepatitis B virus (HBV) infection is generally low in Western countries, pockets of higher prevalence may exist in areas with large immigrant populations. The aim of this study was to obtain further information on the prevalence of viral hepatitis in a multi-ethnic area in the Netherlands. METHODS We conducted a community-based study in a multi-ethnic neighborhood in the city of Rotterdam, the Netherlands, including both native Dutch and migrant participants, who were tested for serological markers of hepatitis A, hepatitis B, and hepatitis C infection. RESULTS Markers for hepatitis A infection were present in 68% of participants. The prevalence of hepatitis B core antibodies (anti-HBc), a marker for previous or current infection, was 20% (58/284). Prevalence of hepatitis A and B varied by age group and ethnicity. Two respondents (0.7%) had chronic HBV infection. The prevalence of hepatitis C was 1.1% (3/271). High levels of isolated anti-HBc were found. CONCLUSIONS We found a high prevalence of (previous) viral hepatitis infections. This confirms previous observations in ethnic subgroups from a national general population study and illustrates the high burden of viral hepatitis in areas with large immigrant populations.