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P Beutels

Publications and source records attributed to P Beutels.

At least 19 recordsLinked to original sources

Social mixing patterns for transmission models of close contact infections: exploring self-evaluation and diary-based data collection through a web-based interface.

Although mixing patterns are crucial in dynamic transmission models of close contact infections, they are largely estimated by intuition. Using a convenience sample (n=73), we tested self-evaluation and prospective diary surveys with a web-based interface, in order to obtain social contact data. The number of recorded contacts was significantly (P<0.01) greater on workdays (18.1) vs. weekend days (12.3) for conversations, and vice versa for touching (5.4 and 7.2 respectively). Mixing was highly assortative with age for both (adults contacting other adults vs. 0- to 5-year-olds, odds ratio 8.9-10.8). Respondents shared a closed environment significantly more often with >20 other adults than with >20 children. The difference in number of contacts per day was non-significant between self-evaluation and diary (P=0.619 for conversations, P=0.125 for touching). We conclude that self-evaluation could yield similar results to diary surveys for general or very recent mixing information. More detailed data could be collected by diary, at little effort to respondents.

Adult↗

[Varicella-zoster virus seroprevalence in nursery and day-care workers in Lyon (France)].

OBJECTIVE: Varicella is a potential occupational hazard for susceptible individuals working in pediatric institutions because infected adults run a greater risk of severe or even fatal varicella and because the disease is so common in children and so contagious. The seroprevalence of varicella-zoster virus (VZV) was examined in a sample of day-care workers in Lyon (France) to determine whether a targeted vaccination policy was needed. METHODS: Two hundred forty-one sera were sampled and analysed with an Elisa test between March and May 2001. Histories of past VZV infection were collected via questionnaires documented either before or after consultation of medical records or other sources of information. RESULTS: The overall VZV seroprevalence was 99.6%. The positive predictive values of past varicella histories (documented or not) were>99% showing that a history of previous varicella in day-care workers was reliable. However, only 68 to 71% of these with serologically confirmed varicella reported a prior history of varicella. All subjects reporting a non-positive history of varicella were seropositive. CONCLUSIONS: Virtually all day-care workers enrolled in this study presented serological evidence of VZV so that sub-populations at risk for varicella infection for which VZV vaccination may be effective could not be identified. However, the VZV seroprevalence of the workers in pediatric institutions being presumably higher than that of the general adult population (94-96.3%), vaccination of susceptible young recruits before any exposure to the VZV, or even vaccination of students willing to work in a pediatric institution, may be positive.

Adult↗

Varicella vaccination in Australia.

Varicella zoster virus (VZV) causes both chickenpox and herpes zoster and is responsible for a significant disease burden, including hospitalizations and deaths, in Australian children and adults. Varicella vaccine has been available in Australia for 5 years; however, from November 2005, it will be funded for use in all susceptible children at 18 months and 10-13 years of age under the National Immunisation Program. Experience with universal varicella vaccination of children in the USA over the last 10 years has shown that the vaccine is safe and highly effective in reducing varicella-related disease. This review summarizes the epidemiology of VZV-related disease in Australia, the use of varicella vaccine and the international experience with vaccine efficacy and safety. The potential impact of varicella vaccination on the incidence of herpes zoster is also discussed.

Adolescent↗

The cost of measles in industrialised countries.

The aim of this study is to estimate the costs of measles and measles control in 11 industrialised countries with varying levels of measles vaccine coverage. Country-specific annual incidence of measles, measles immunization policy, coverage and costs data were collected. The average societal costs of measles cases and immunisation programme per capita were calculated. These 11 countries spend together over US$ 151 million every year to treat and control measles. Per capita costs of measles control tend to be higher in countries with poorer measles control programmes (for instance, Italy has the highest incidence and highest overall costs), though many other factors, such as the number of antigens given per clinic visit and the local price of MMR also affect the efficiency of the programme. The costs estimates presented here can be used to estimate potential savings that might accrue from changes to measles control programmes.

Costs and Cost Analysis↗

Economic evaluations of hepatitis B immunization: a global review of recent studies (1994-2000).

A search was carried out for economic evaluations of hepatitis B (HBV) vaccination, published between 1994 and 2000. The results of these studies are discussed according to the level of HBV endemicity. The great majority of these evaluations were carried out for industrialized countries, for the most part situated in areas of low to very low HBV endemicity. In countries of very low endemicity economic evaluations have yielded contradictory results, depending on the type of epidemiological model they used. The cost-effectiveness of adding universal to selective vaccination strategies in these countries depends on the selective strategies' ability to sufficiently identify, reach and fully vaccinate persons in various risk groups. In areas of low, intermediate and high endemicity, universal vaccination seems justifiable on the basis of economic evaluation. In general, the accuracy of the models has improved over the years, but still the transparency, completeness and comparability of analyses could improve considerably. By noting this, the suitability of different methodologies for different areas of endemicity and vaccination strategies is discussed. It is recommended that specific guidelines for economic evaluation of the prevention of infectious diseases be developed to guarantee the relevance of and to improve the comparability between studies.

Cost-Benefit Analysis↗

Additional hospital stay and charges due to hospital-acquired infections in a neonatal intensive care unit.

A comparative retrospective cohort study was performed to evaluate the influence of hospital-acquired infection (HAI) in neonates on additional charges and hospital stay. Neonates admitted between October 1993 and discharged alive before December 1995 at the neonatal intensive care unit of a university hospital were studied. Of 515 neonates, 69 (13%) had one or more HAI; 45 (20 with proven HAI, 25 with suspected HAI) were matched to 45 controls. After matching for gestational age, surgery, artificial ventilation and patent ductus arteriosus, central vascular catheter utilization was the only factor significantly associated with HAI. Charges were obtained from hospital discharge abstracts and the duration of hospitalization from patients' files. The mean additional length of hospital stay in neonates with HAI was 24 days (54 days vs. 30 days, P= 0.002) but did not differ significantly in patients with proven or suspected HAI (67 days vs. 51 days, P> 0.05). The mean extra charges for patients with a HAI were 11 750 EURO (9635 pounds). Accommodation accounted for 72%, fees for 22%, pharmaceuticals for 5% and ancillary items for 1% of these extra charges. The mean charges per day were similar for controls [443 EURO (363 pounds)] and HAI patients [453 EURO (372 pounds)]. Overall charges and charges per day were similar for neonates with proven and suspected HAI.

Bacterial Infections↗

The disease burden of hepatitis B in Uzbekistan.

OBJECTIVE: To describe the burden of hepatitis B illness in Uzbekistan by means of model-based estimates. METHODS: A mathematical simulation model was developed to mimic the disease evolution of hepatitis B and calculate the size and age of specific HBV patient groups, defined according to the severity of their illness. RESULTS: The calculations indicate that of 678000 neonates in Uzbekistan, 159185 (235 per 1000) would incur an HBV infection at some time during their lives. About 55095 persons (81 per 1000) would become chronic carriers of hepatitis B and 6307 persons (9.3 per 1000) are expected to die due to hepatitis B before they would die from another cause. In the overall population, we calculated that about 3074 Uzbeki die each year from the consequences of hepatitis B. Only 3.2% of these premature HBV-deaths are due to acute hepatitis B, whereas 96.8% are due to chronic hepatitis B. It was calculated that 2.1% of all deaths (or 1 in 47 deaths), and nearly 25% of deaths (or one in four deaths) between 30 and 40 years of age in Uzbekistan are due to hepatitis B. Vaccination seems easily defensible on the basis of rudimentary but very conservative cost-effectiveness calculations ($84 per carrier prevented; $735 per death prevented and $22 per life-year gained). CONCLUSION: Hepatitis B represents a huge health problem in Uzbekistan, especially in young adults. The potential for prevention by vaccination seems very high, but demands a long-term vision if chronic hepatitis, in particular, is to be reduced. Routine hepatitis B vaccination was found to be a relatively cost-effective intervention in Uzbekistan.

Adolescent↗

Mathematical models for assessment of long-term persistence of antibodies after vaccination with two inactivated hepatitis A vaccines.

Very few studies with inactivated hepatitis A vaccines were designed for long-term follow-up of antibody persistence. Based on the serological data from these vaccine trials, mathematical models were developed to predict the decrease of anti-hepatitis A virus (anti-HAV) antibodies after vaccination. This study was designed to compare Avaxim (0-6 months) to Havrix 720 (0-1-6 months). In this paper, both groups of vaccinees are described considering the age, gender, and weight of the subjects at enrollment. For mathematical modelling, two different approaches were used: one starting the calculations from the geometric mean titres (GMTs) at each point in time, the other basing the calculations on individual anti-HAV titres. Both vaccines are very immunogenic, although Avaxim shows a higher GMT at each point in time. When these data are used in mathematical models to predict the persistence of anti-HAV antibodies, both vaccines (Avaxim and Havrix 720) show similar long-term antibody kinetics. Antibody levels > or = 20 mIU/ml are estimated to last on average for at least 10 years after completion of the full vaccination course. Ten years after the full course, approximately 53% of subjects are estimated to have antibody levels > or = 20 mIU/ml. At 15 years, these levels will be maintained by about 34% of vaccinees. Avaxim and Havrix 720 show a similar long-term profile of persistence of anti-HAV. A mathematical model based on GMTs appeared to give equivalent results to a model based on individual serological data. The GMT method is easier to apply than the individual based method. However, the advantage of the latter method is the possibility of calculating confidence limits for the predicted values and making estimates of the percentage of subjects having a certain level of antibody titres at a certain time.

Adolescent↗

An economic evaluation of universal pertussis vaccination in Italy.

An economic evaluation was performed of universal acellular pertussis vaccination in Italy, where until recently the overall coverage of pertussis vaccination was estimated at 50%. Over the last two years coverage seems to have increased rapidly. By means of a mathematical simulation model, the consequences of pertussis vaccination in terms of both health effects and economic costs were calculated for a single birth cohort followed for 6 years. Incremental analyses were performed for each additional 10% increase in coverage from 50-90%. The results indicate that a 50% coverage rate of pertussis vaccination in Italy was not optimal on the basis of cost-effectiveness and cost-benefit considerations. Additional increases in coverage were found to yield extra health gains at modest net costs or even potential net savings to the health care sector. For example, an increase in coverage to 90% would yield direct net savings of US$42 per extra vaccinee in comparison to a situation of 50% coverage. The total net savings for this strategy would be well over US$100 per additional vaccinee. In the sensitivity analysis, the positive relationship between incremental coverage and incremental efficiency remained unchanged.

Cost-Benefit Analysis↗

Economic evaluations applied to HB vaccination: general observations.

Since HB vaccines became available, there have been many economic evaluations on HB vaccination programs. The majority of them were for countries of low endemicity. Economic evaluations for countries of very low endemicity with a good surveillance system in place and high attendance of Sexually Transmitted Disease- and Intra VenousDrug Users-clinics indicate that risk group vaccination is the most cost-effective strategy to control HB. In analyses for low endemic countries, recommendations have shifted from risk group vaccination in the eighties to universal vaccination of either infants or adolescents in the nineties. For the health care payer, the resulting cost-effectiveness ratios of universal vaccination were favourable in comparison to those of other preventive interventions. From a societal point of view, universal HB vaccination was found to be cost-saving in these countries. Few published studies were set in countries of intermediate to high endemicity. They indicate that for the health care payer universal HB vaccination of neonates or infants is cost-effective compared to other interventions, or even cost-saving. Further studies are needed to support decision making in high endemic countries, where both the need for HB vaccination and the pressure on resources are highest.

Hepatitis B↗

An economic evaluation of hepatitis A vaccination in Dutch military personnel.

We analyzed the cost-effectiveness of hepatitis A vaccination regimens using a mathematical simulation model. Passive immunization and two active vaccination strategies (with and without prior screening) were compared with "doing nothing." Hepatitis A antibodies were determined in 2,325 Dutch marines; other input data were retrieved from published and unpublished sources. The prevalence of hepatitis A antibody was 14%. Screening before vaccination was identified as appropriate at a prevalence > 20%. Passive immunization was the cheapest prevention for a single 6-month deployment per 10 years. The inactivated vaccine containing 1,440 enzyme-linked immunosorbent assay units without prior screening was identified as the best option for more frequent deployments. It was cost-saving with two or more missions per 10 years. A 5.3% hepatitis A attack rate validated the investment for this policy. Overall, immunization with inactivated hepatitis A vaccine without prior screening proved to be the optimum strategy for troops at regular risk.

Adolescent↗

Costs and benefits of routine varicella vaccination in German children.

This study assessed the costs and benefits of introducing routine varicella vaccination to healthy children in Germany. Three vaccination strategies were compared with that of no prevention: vaccination of all 15-month-old children: vaccination of susceptible 12-year-olds (adolescent); and a combination of strategies (children including catch-up). From a purely economic viewpoint, the adeolescent strategy was optimal: It was the only one that resulted in net direct cost savings. However, since this strategy may be less acceptable from a medical or organizational point of view and because total net savings were the highest, a second option was to begin immunization starting with the 15-month-old children and to use the catch-up strategy for 11 years (total benefit-to-cost ratio (BCR), 4.72:1; cost-effectiveness ratio (CER), DM 6915 per life-year saved) and from year 12 on to use the first strategy (BCR, 4.60:1; CER, DM 19,735 per life-year saved).

Adolescent↗

Economic evaluation of vaccination.

With increasing expenditures in healthcare, in absolute terms as well as in relative terms, interest in the efficiency of certain interventions in healthcare has also increased. Faced with the limitations of the healthcare budget, budget holders try to find the optimal way of dividing their funds over different healthcare provisions, without discarding human and medical considerations. In economic terms, this process could be called the 'optimal allocation of scarce resources over the inputs of a function of production'. The means of production would then be 'the provision of healthcare', whereas the output would be 'improvement of health'. Clearly choices have to be made with regard to spending the healthcare budget. One of the instruments that can help in making such choices is the economic evaluation. In economic evaluations of vaccinations, different vaccination strategies are defined. The consequences in terms of costs and effects of each strategy are being calculated and compared with a reference strategy, which is often the nonintervention strategy, i.e. 'no vaccination'. According to the way in which the benefit or the output of vaccination-'improvement of health'-is measured, a distinction is made between various methods of economic evaluation: in a cost-effectiveness analysis, health gains are measured in natural units (e.g. prevented infections, prevented illness days, life-years gained, etc.); in a cost-utility analysis, the quality of the health gains is taken into account (e.g. quality-adjusted life-year); and in a cost-benefit analysis, health gains are converted into monetary units. Costs can be divided into direct and indirect costs. Direct costs are directly related to medical treatments (medication, laboratory tests, consultations, etc.) or to vaccination (e.g. purchasing price of the vaccine, costs for administering the vaccine, treatment of side effects, etc.). Costs indirectly related to treatments and vaccination are mainly costs of lost productivity due to disease morbidity or mortality, and opportunity costs. In comparison with other vaccine-preventable infections, influenza vaccination for the elderly seems acceptable from an economic point of view (about $US650 per life-year gained, in 1981). Cost-effectiveness ratios of other vaccinations range from about $US720 per life-year gained for universal hepatitis B vaccination to about $US190,000 per life-year gained for universal Haemophilus influenzae type by vaccination. Because of differences in methods, the representation of results, and country-specific parameters, different economic evaluations of the same vaccination strategy may show divergent results. Therefore, until sufficient standardisation of economic evaluations exists, comparisons of the sort we are making here should be interpreted with prudence.

Cost-Benefit Analysis↗

Hepatitis A infection in aircrews: risk of infection and cost-benefit analysis of hepatitis A vaccination.

BACKGROUND: Since a hepatitis A vaccine (HAV) with long-lasting efficacy has become available, its indication in airline crews needs to be determined. HYPOTHESIS: Destinations in developing countries are a risk factor for hepatitis A infection in airline crews, and vaccination is cost-beneficial. METHODS: Retrospective analysis was performed for all Swissair medical files for the period 1987-91. Denominator and cost data were obtained by the personnel department, and a cross-sectional seroepidemiological survey was performed in 734 Sabena staff. RESULTS: Among 3,322 Swissair crewmembers who spent an average of 45 nights in developing countries, 22 hepatitis A infections occurred. For the non-immune crewmembers, the overall annual incidence rate was 1.53 per 1000, whereas the incidence rate while staying in a high risk country was 12.2 per 1000. Cockpit crews with destinations limited to Europe had a rate of zero. Male flight attendants had a threefold higher rate as compared to female flight attendants or pilots. In Sabena, anti-HAV seroprevalence was 33.3%. Increased rates were observed in male as compared to female flying crews and in employees stationed abroad, whereas flying personnel had no higher rate than ground personnel. Simplified comparison of cost of infection and cost of vaccination indicates that vaccination may be cost-saving to the airline company for both male flight-attendants and pilots. CONCLUSIONS: Hepatitis A vaccination may be recommended to staff stationed in high risk countries and to flying crews with such destinations.

Adult↗