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Background: The long average incubation time from HIV infection to AIDS makes it difficult to estimate recent HIV transmission from AIDS incidence data. Age-period-cohort (APC) analysis can separate out the effects of age, calendar time and birth cohort to provide a clearer picture of transmission trends.Methods: AIDS incidence data from 1981 to 1994 among intravenous drug users (IDU) for 12 Western European countries were used. Yearly incidences per 100,000 population or 100,000 person-years were calculated by age at diagnosis and 5-year birth cohort (1950-1954, 1955-1959, 1960-1964, 1965-1969 and 1970-1974), and corrected for reporting delay. Incidence patterns were compared between birth cohorts and countries.Results: For most countries the impact was greatest on the cohort born 1960-1964. Comparing incidence patterns in the 1965-1969 to 1960-1964 cohorts suggest the epidemic has plateaued at low to intermediate levels in Austria, Greece and the North-Western European countries, and at high levels in France, Italy and Switzerland. For most countries transmission amongst the 1970-1974 as compared to the 1965-1969 cohorts could not be assessed due to small numbers and short follow-up time. In Spain the epidemic was uncontrolled with a high incidence among recent birth cohorts. In Portugal the epidemic was still at an early and expanding phase.Conclusions: The APC analysis revealed large country differences in the dynamics of the HIV/AIDS epidemic among IDU. Full interpretation of these differences is dependent on information from other sources about the local public health response and trends in drug injecting behaviours. Earlier introduction of the virus and higher prevalence of injecting drug use may explain some of the generally higher incidence in Southern European countries, but the larger part of it is most likely explained by local characteristics of drug users, such as younger age and more frequent sharing of needles and syringes, and a less effective public health response. [ABSTRACT FROM AUTHOR]

Background: The effects of the implementation of a new Dutch hepatitis B virus (HBV) vaccination strategy (1991) for expatriates on HBV vaccination status and HBV infection prevalence were evaluated in a group of 864 expatriates returning from HBV-endemic areas.Methods: During a routine medical examination at the participating medical centres Dutch expatriates were asked to complete a questionnaire and to donate a serum sample for HBV testing. Blood was tested for antibodies against the hepatitis B core (anti-HBc) and surface antigens (anti-HBs). The serological data were related to information gathered on aspects of residence, sexual risk behaviour and occupational risks.Results: A significantly higher percentage of expatriates (37%) were vaccinated compared to a previous study in 1987-1989 (14%). However, the percentage of expatriates with HBV infection markers (5%) had not decreased significantly. Moreover, the risk for HBV infection, as determined with a questionnaire, was still affected by well-known risk factors such as homosexual contacts (odds ratio [OR] = 6.6, 95% CI: 1.7-26), more than five casual local partners (OR = 3.6, 95% CI: 1.2-11) and more than five occupational accidents in the last 3 years (OR = 20, 95% CI: 2-187). Detailed analysis of the vaccination status indicated that especially young female expatriates with low risk behaviour (65%) were protected, while older male expatriates with high risk behaviour were less protected (20%).Conclusion: We conclude that the new vaccination strategy has resulted in a higher percentage of expatriates protected. However, only a small proportion was reached of those at highest risk for HBV infection. [ABSTRACT FROM AUTHOR]

In this study on occupational risks of HIV infection among 99 Dutch medics working in AIDS endemic areas, 61% reported percutaneous exposures during an average stay of 21 months. The mean number of injuries was lower among physicians (2.0 versus 3.9 per year) and higher among nurses (1.9 versus 1.2) than in previous research conducted in 1987-1990 among Dutch medics returning from Africa. But the reduction of exposures among physicians might be explained by the fact that the number of procedures they carried out was less in the later study. Also among nurses a shift of tasks was seen. On the basis of an estimated HIV prevalence in the patient population of 19%, a chance of transmission per accident of 0.3%, and 1.9 percutaneous exposures per year, the mean occupational risk of HIV infection per year can be estimated at 0.11% per person. Besides length of stay and number of activities, characteristics of the work setting were associated with the frequency of different kinds of injuries. From the analysis of 109 extensive descriptions of recent accidents, it appeared that the majority of the injuries occurred during routine activities and were self-inflicted. Injuries with hollow needles usually occurred after the actual medical act (e.g. during recapping). Carelessness (e.g. due to fatigue) or being in a hurry (e.g. because of an emergency) were also often the cause of percutaneous injuries, as were the poor quality of the equipment, lack of professional skills, or a combination of these factors. Prevention activities are still important to reduce the frequency of occupational exposures. But they will not eliminate them totally; from the descriptions of recent exposures it was clear that some of the injuries occurred in spite of precautions. [ABSTRACT FROM AUTHOR]

Among people who work abroad, sexual activity and therefore the risk of HIV infection appear to be relatively high. Little is known about the factors that influence sexual conduct when staying abroad, separated from their usual social environment. This is why 55 expatriates who had been sexually active in AIDS endemic areas were selected for an in-depth interview from the original sample of 864 Dutch expatriates participating in a study on sexual behaviour and HIV infection. The social and cultural context in which the sexual contacts took place was addressed in these interviews. Qualitative analysis of the data led to the identification of four styles with regard to the meaning of and motivations for having sex abroad: 'the unprepared', 'the fanatical', 'the unaffected' and 'the slightly accessible'. These styles are described separately and attention is paid to the association of these styles with protection behaviour. [ABSTRACT FROM AUTHOR]

Discusses the clinical epidemiological and resource utilization issues arising from HIV/AIDS disease-associated mental disorder dementia in Europe. Prevalence of dementia in persons with HIV infection; Impact of HIV-related dementia on both the individuals and the health care system; Evaluation of hospital resource utilization.

In this study it was assessed whether homosexual men who practiced unprotected anogenital intercourse with steady and non-steady partners subjectively perceived their behaviors to be risky. Data were collected from 165 homosexual participants in an ongoing cohort study who reported unprotected anal sex. A variety of psychological factors which could possibly explain why some men were at risk but did not perceive their behavior as such, were investigated. This study showed that the majority of men who engaged in sexual risk behaviors within their primary relationship did not subjectively appraise their behavior as risky. The factors found to explain this discrepancy were not having had sex with a partner known to be HIV infected or to have AIDS (for couples of unknown serostatus) and not having had friends or relatives who were ill or had died (for seronegative couples). Homosexual men who had unprotected anal sex with casual partners generally were aware of the risk involved in their behavior. [ABSTRACT FROM AUTHOR]

National Immunization Technical Advisory Groups (NITAGs) are facing increasingly complex vaccination issues together with a lack of human resources for evidence assessment and data analysis. One way to reduce these burdens could be to share some of the preparatory work across NITAGs. We conducted an inventory of all the advisory reports issued by five well-established European NITAGs from 2011 to 2014 to assess overlaps in issues and activities. A total of 104 advisory reports were retrieved. Advisory reports on the same issues were compared to identify overlapping activities and processes. Advisory reports issued by the five NITAGs showed little overlap in issues and processes. A first step towards efficient collaboration would be to establish an independent platform to provide insight into each NITAG's work and to facilitate the exchange of agendas, assessment frameworks and evidence., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Many experts on vaccination are convinced that efforts should be made to encourage increased collaboration between National Immunization Technical Advisory Groups on immunization (NITAGs) worldwide. International meetings were held in Berlin, Germany, in 2010 and 2011, to discuss improvement of the methodologies for the development of evidence-based vaccination recommendations, recognizing the need for collaboration and/or sharing of resources in this effort. A third meeting was held in Paris, France, in December 2014, to consider the design of specific practical activities and an organizational structure to enable effective and sustained collaboration. The following conclusions were reached: (i) The proposed collaboration needs a core functional structure and the establishment or strengthening of an international network of NITAGs. (ii) Priority subjects for collaborative work are background information for recommendations, systematic reviews, mathematical models, health economic evaluations and establishment of common frameworks and methodologies for reviewing and grading the evidence. (iii) The programme of collaborative work should begin with participation of a limited number of NITAGs which already have a high level of expertise. The amount of joint work could be increased progressively through practical activities and pragmatic examples. Due to similar priorities and already existing structures, this should be organized at regional or subregional level. For example, in the European Union a project is funded by the European Centre for Disease Prevention and Control (ECDC) with the aim to set up a network for improving data, methodology and resource sharing and thereby supporting NITAGs. Such regional networking activities should be carried out in collaboration with the World Health Organization (WHO). (iv) A global steering committee should be set up to promote international exchange between regional networks and to increase the involvement of less experienced NITAGs. NITAGs already collaborate at the global level via the NITAG Resource Centre, a web-based platform developed by the Health Policy and Institutional Development Unit (WHO Collaborating Centre) of the Agence de Médecine Préventive (AMP-HPID). It would be appropriate to continue facilitating the coordination of this global network through the AMP-HPID NITAG Resource Centre. (v) While sharing work products and experiences, each NITAG would retain responsibility for its own decision-making and country-specific recommendations., (Copyright © 2016. Published by Elsevier Ltd.. All rights reserved.)

Given the ethical aspects of vaccination policies and current threats to public trust in vaccination, it is important that governments follow clear criteria for including new vaccines in a national programme. The Health Council of the Netherlands developed such a framework of criteria in 2007, and has been using this as basis for advisory reports about several vaccinations. However, general criteria alone offer insufficient ground and direction for thinking about what the state ought to do. In this paper, we present and defend two basic ethical principles that explain why certain vaccinations are the state's moral-political responsibility, and that may further guide decision-making about the content and character of immunisation programmes. First and foremost, the state is responsible for protecting the basic conditions for public health and societal life. Secondly, states are responsible for promoting and securing equal access to basic health care, which may also include certain vaccinations. We argue how these principles can find reasonable support from a broad variety of ethical and political views, and discuss several implications for vaccination policies., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

WHO have long called for universal vaccination against hepatitis B worldwide. However, in north-western Europe low incidence of the disease has fueled debate whether targeted or universal vaccination strategies are the way to go for. Careful assessment has made it clear that the extensive targeted hepatitis B vaccination programmes in the Netherlands nevertheless fail to reach a significant part of the risk groups and have not succeeded in eliminating the disease. Modelling suggests that the public health benefits obtained through targeted programmes could be augmented considerably by universal vaccination. Therefore, the Minister of Health of the Netherlands has decided to implement universal vaccination by October 2011. We illustrate the case of the Netherlands and explore lessons, which can be learnt from the vaccination programmes against HPV and influenza A/H1N1 and how to prepare for a potential public debate that might arise when implementing universal vaccination against hepatitis B., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

To date, the policy to control hepatitis B in the Netherlands is to vaccinate specific risk groups, rather than all children. Low incidence of the disease has fueled debate whether such a targeted vaccination strategy or rather a universal strategy, as recommended by the World Health Organization, is appropriate. The standard framework for assessing whether a particular vaccination should be included in a public programme, as recently proposed by the Health Council of the Netherlands (HCN), was applied to the various options for hepatitis B vaccination. This framework includes seven selection criteria, grouped under five thematic headings: seriousness and extent of the disease burden, effectiveness and safety of the vaccination, acceptability of the vaccination, efficiency of the vaccination, and priority of the vaccination. From about 1990 the disease burden has stayed more or less the same over time and careful assessment has made it clear that the targeted approach has failed to reach a significant part of the risk groups. Models suggest that the public health benefits obtained through targeted programmes could be augmented considerably by universal vaccination. Based on the assessment that universal vaccination means better protection for high-risk groups as well as the whole population, the HCN calls for universal immunisation, even though hepatitis B to a large extent is limited to specific high-risk groups. Should the Netherlands adopt universal vaccination, several immunisation programmes targeted to high-risk groups will, however, remain of crucial importance for years to come., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

As more and more new vaccines are developed and brought to the market, governments have to make decisions about which vaccinations to include in public programmes. This paper describes the experience in the Netherlands in developing a framework for assessing whether a vaccination should be included in the National Immunization Programme (NIP). Bearing in mind the public nature, the factors that determine a vaccine's suitability for inclusion in a communal vaccination programme have been translated into seven selection criteria, grouped under five thematic headings: seriousness and extent of the disease burden, effectiveness and safety of the vaccination, acceptability of the vaccination, efficiency of the vaccination, and priority of the vaccination. The seven criteria and the explanation of them provide a framework for the systematic examination of arguments for and against the inclusion and prioritisation of particular vaccinations. As an illustration, the vaccinations currently provided in the Netherlands through public programmes as well as 23 'candidate' vaccinations are assessed against the seven criteria. The proposed assessment framework including the selection criteria can take full account of the values and specificities as they may differ between situations and countries; the transparency of the approach may help to clarify which elements of the assessment are pivotal in specific situations. Using the criteria furthers a trustworthy, transparent and accountable process of decision-making about inclusion of new vaccinations in public vaccination programmes and may help to retain public confidence., (Copyright 2010 Elsevier Ltd. All rights reserved.)

Objectives: To adapt and improve methodology for back-calculation of AIDS in Europe and to examine the feasibility of estimating past HIV incidence by birth cohort., Methods: Empirical Bayesian back-calculation (EBBC) used Markov disease progression models, modified to allow for three diseases added to the AIDS case definition in 1993 and for pre-AIDS mortality, and estimation by penalized maximum likelihood with a neighbour prior. EBBC by 5-year birth cohort assumed a minimum age at infection and age-dependent progression rates; three versions, with varying age effects, were investigated using AIDS cases diagnosed prior to the introduction of highly active antiretroviral therapies (HAART)., Results: Compared with the no age-effect version, EBBC by birth cohort tended to produce flattened HIV incidence curves in country-exposure groups with < 1000 AIDS cases, reflecting effects of the neighbour prior when data become sparse. Otherwise, birth cohort analysis, with moderate effects of age on progression, gave initially increasing incidence curves and consistent patterns across countries, with the 1960-1964 cohort most affected. In the European Union, incidence is estimated to have peaked in 1983 among homosexual men and in 1988 among injecting drug users; 460000 persons were estimated to be living with HIV/AIDS at the end of 1995., Conclusions: Our improved methodology deals effectively with the change in AIDS case definition and has allowed quantitative assessments of the HIV epidemic by birth cohort using all AIDS cases diagnosed before 1996, thus providing a sound basis for public health policy at a time when estimation of more recent prevalence is compromised by the effects of HAART.

Objective: To estimate the cost effectiveness of universal, voluntary HIV screening of pregnant women in England., Design: Cost effectiveness analysis. Cost estimates of caring for HIV positive children were based on the stage of HIV infection and calculated using data obtained from a London hospital between 1986 and 1996. These were combined with estimates of the health benefits and costs of antenatal screening so that the cost effectiveness of universal, voluntary antenatal screening for HIV infection in England could be estimated., Main Outcome Measures: Lifetime, direct costs of medical care of childhood HIV infection; life years gained as a result of the screening programme; net cost per life year gained for different pretest counselling costs; and different prevalence rates of pregnant women who were unaware that they were HIV positive., Results: Estimated direct lifetime medical and social care costs of childhood HIV infection were pound178 300 using a 5% discount rate for time preference (1995-6 prices). In high prevalence areas screening pregnant women for HIV is estimated to be a cost effective intervention with a net cost of less than pound4000 for each life year gained. For areas with comparatively low prevalence rates, cost effectiveness could be less than pound20 000 per life year gained, depending on the number of pregnant women who are unaware that they are infected and local screening costs., Conclusions: Our results confirm recent recommendations that universal, voluntary antenatal HIV screening should be implemented in the London area. Serious consideration of the policy should be given for other areas in England depending on local prevalence and screening costs.

HIV surveillance in homosexual men is poor in most countries, as this risk group is difficult to sample. The aim of this study is to test the feasibility of reaching homosexual men for national HIV surveillance using gay community media. In 1989, a questionnaire on general gay issues, with a section on AIDS, was included in a widely sold gay magazine in the Netherlands. Among 17,700 sold copies, 1134 responses were obtained from males (6%). Of these, 669 men (59%) gave their address, of which in turn 84% responded to a questionnaire on risk behaviour in 1990. In 1991/1992, the 669 men were asked to participate in an HIV serosurvey, in which eventually 308 participated with a blood test (46%) and 147 without (total 68%). Participation in the serosurvey with blood test was associated with reporting multiple partners in 1989. Twenty participants were infected (6.5%). In logistic regression analysis, risk factors for infection were recent unprotected receptive anal intercourse with multiple partners (odds ratio (OR): 10.7; 95% confidence interval (CI): (2.18-52.2); one partner 1.17 (0.31-4.48); none 1) and living in Amsterdam (OR: 3.92; 95% CI: (0.99-15.5); urbanised western Netherlands 2.15 (0.57-8.03); elsewhere 1), while a high educational level was protective (OR: 0.29 (0.08-0.96); middle 0.41 (0.11-1.54); low 1). Among those who participated in 1991/1992, risk behaviour increased between 1989 and 1991/1992 (reporting multiple casual partners rose from 55% to 64%; reporting inconsistent condom use with receptive anal sex from 58% to 71%). Using a predictive model which included self-reported serostatus in 1989, the HIV prevalence rate in 1991/1992 among all male responders to the 1989 questionnaire was estimated to be 5.3% (95% CI: 3.1 7.7%). In conclusion, unless initial response is improved, recruitment through a gay magazine may not allow reliable estimates of HIV prevalence in homosexual men. However, it can be useful at the national level for monitoring changes in prevalence and risk behaviour over time, geographical differences and risk factors for infection.

Among people who work abroad, sexual activity and therefore the risk of HIV infection appear to be relatively high. Little is known about the factors that influence sexual conduct when staying abroad, separated from their usual social environment. This is why 55 expatriates who had been sexually active in AIDS endemic areas were selected for an in-depth interview from the original sample of 864 Dutch expatriates participating in a study on sexual behaviour and HIV infection. The social and cultural context in which the sexual contacts took place was addressed in these interviews. Qualitative analysis of the data led to the identification of four styles with regard to the meaning of and motivations for having sex abroad: 'the unprepared', 'the fanatical', 'the unaffected' and 'the slightly accessible'. These styles are described separately and attention is paid to the association of these styles with protection behavior.

Objectives: To compare HIV prevalence estimates (total number infected) by using extrapolation from surveys on infection rate and risk behaviour (EIR) in specific segments of the population and back-calculation (BC) on reported AIDS cases. To discuss potential sources of bias and error, and to identify areas for improvement of the methodology., Design: Systematic comparison and epidemiological assessment of data input, underlying assumptions, and output., Methods: Low, possibly unbiased and high estimates of HIV prevalence as of January 1996 for homo/bisexual men, injecting drug users. heterosexual men and women with multiple partners, and blood transfusion recipients and haemophiliacs were derived from surveys and continuous data collections on HIV infection rate and risk behaviour in the Netherlands between 1992 and 1996. These were compared with estimates (point and 95 % CI) by empirical Bayesian BC on AIDS cases 1982-1995., Results and Conclusions: The estimate of HIV prevalence by EIR was 13,806 with low and high estimates of 9619 and 17,700, respectively. The HIV prevalence estimate by BC was 8812 (95% CI: 7759-9867). The available data from EIR are too limited for accurate estimates of HIV prevalence. EIR estimates could be improved considerably with more precise data on prevalence of risk behaviours and HIV prevalence rate for homosexual men. More confidence can be put in the BC estimates, but these could be underestimates because of the age effect on incubation time, pre-AIDS treatment and relapse of risk behaviour. BC estimates could be improved by a better representation of the incubation time distribution (including the effect of age there-upon), better data on the effectiveness and uptake of pre-AIDS antiretroviral treatment and prophylaxis of opportunistic infections, and on the level of underreporting.

Objectives: To study trends in AIDS incidence in Europe by age and year of birth., Design: Age-period-cohort analyses were adopted to distinguish the different time factors of calendar year, age and year of birth., Methods: Non-aggregate AIDS incidence data from 12 European countries (1978-1994) were adjusted for reporting delay and expressed per unit of population (per 100000 persons or 100000 person-years). Age-specific incidence patterns (absolute level and rate of increase) were compared between 5-year birth cohorts for homo-/bisexual men, injecting drug users (IDU) and heterosexual contact cases., Results: Mean age at diagnosis increased strongly amongst IDU, but less so among homo-/bisexual men and heterosexual contact cases. Of a total 110646 reported cases (116311 after adjustment for reporting delay), 87167 (78.8%) were among people born in 1950-1974 [91951 (79.1%) after adjustment for reporting delay]. The relative impact on specific birth cohorts differed strongly by exposure group. Incidences at age ranges of 20-24 and 25-29 years among cohorts born in 1965 and after were about the same level (homo-/bisexual men, IDU) or higher (heterosexual contact cases) than older birth cohorts when these were in the same age range; rates of increase were less among homo-/bisexual men and IDU, but higher among heterosexuals. There were large differences between counties., Conclusions: Overall, AIDS incidence among cohorts born in 1965 and after is about the same level (homo-/bisexual men, IDU) or higher (heterosexual contact cases) than older cohorts when these were in the same age range. Rates of increase of AIDS incidence curves suggest reduced HIV transmission amongst the most recent cohorts of homo-/bisexual men and IDU, but among young heterosexuals the epidemic is still expanding.

Objective: To assess the prevalence of HIV infection and related risk factors among Dutch expatriates returning from assignment in sub-Saharan Africa, Latin America, and South and South-east Asia., Methods: From July 1994 to January 1996, a questionnaire on the risks of sexual exposure was completed by 864 respondents, and blood samples were taken., Results: Of the 634 men, 41% reported having sex with casual or steady local partners and 11% with casual or steady expatriate partners, during an average stay of 26 months in the previous 3 years. Of the 230 women, these figures were 31 and 24%, respectively. Of the men with local casual partners (29%), 59% paid for sex at least once. For men as well as women, having sexual contacts abroad was associated with younger age, positive intention prior to departure to have sex abroad, being single at departure, and, only for the men, working for a commercial organization, and feelings of loneliness and boredom. Among men, consistent condom use with casual local partners was 69%, and with casual expatriate partners 63%. Among women, these figures were 64 and 48%, respectively. Consistent condom use with steady local or expatriate partners was much lower. Among men, non-consistent condom use with casual partners was more prevalent if they had been abroad for a longer time, condoms were not taken along from The Netherlands, the country where they were posted was Asian, and the estimated HIV prevalence among the local population was lower. Among the women, non-consistent condom use was more prevalent if condoms were not taken along, and if they did not have the intention before departure to have sex abroad. Of the persons from whom blood could be obtained, one man was HIV-positive. Another man who refused to participate in the study indicated that he was HIV-positive., Conclusions: Although 23% of the expatriates had unprotected sex with partners from endemic areas, very few HIV infections were found. In comparison with a previous study among this population carried out in 1987-1989, which found five out of 1968 expatriates to be HIV-infected, consistent condom use with casual local partners did increase considerably (from 21 to 67%). However, health education is needed to reduce the risk of HIV infection, which should emphasize the sociocultural differences in sexual practices.