Costing infectious disease outbreaks for economic evaluation: a review for hepatitis A.

With the aim to understand and estimate the economic impact of outbreaks of community-acquired infections, we performed a review focusing on hepatitis A outbreaks, and retained 13 papers that had collected relevant cost information during such outbreaks. All costs in this article are expressed in USD, year 2007 values. The costs of hepatitis A outbreaks ranged from USD140 000 to US36 million, and the costs per case in an outbreak situation ranged from USD3824 to USD200 480.

WHO Guide for standardisation of economic evaluations of immunization programmes.

Traditional EPI vaccines are considered to be among the most efficient uses of scarce health care resources. Today, there are many under-used and new vaccines available. In the short- to medium-term, these vaccines will not cost the few cents per dose the traditional vaccines do, but will be 'multi-dollar' vaccines.

Estimating the incidence of symptomatic rotavirus infections: a systematic review and meta-analysis.

Background: We conducted for the first time a systematic review, including a meta-analysis, of the incidence of symptomatic rotavirus (RV) infections, because (1) it was shown to be an influential factor in estimating the cost-effectiveness of RV vaccination, (2) multiple community-based studies assessed it prospectively, (3) previous studies indicated, inconclusively, it might be similar around the world.

Methodology: Pubmed (which includes Medline) was searched for surveys assessing prospectively symptomatic (diarrheal) episodes in a general population and situation, which also reported on the number of the episodes being tested RV+ and on the persons and the time period observed. A bias assessment tool was developed and used according to Cochrane guidelines by 4 researchers with different backgrounds.

The economic impact of SARS in Beijing, China.

Objective: To document the impact of the severe acute respiratory syndrome (SARS) outbreak in Beijing on indicators of social and economic activity.

Methods: Associations between time series of daily and monthly SARS cases and deaths and volume of public train, airplane and cargo transport, tourism, household consumption patterns and gross domestic product growth in Beijing were investigated using the cross-correlation function.

Results: Significant correlation coefficients were found for all indicators except wholesale accounts and expenditures on necessities, with the most significant correlations occurring with a delay of 1 day to 1 month.

Reviewing the cost effectiveness of rotavirus vaccination: the importance of uncertainty in the choice of data sources.

Published health economic evaluations of rotavirus vaccination up until July 2008 were reviewed. We assess whether differences in the results and conclusions of the various studies are due to differences in methodological and modelling choices, and/or the way parameter uncertainty was taken into account, or whether these are merely the result of genuine country/region-specific differences. No unambiguous single answer emerged as to whether universal rotavirus vaccination is or is not cost effective.

Common attitudes about concomitant vaccine injections for infants and adolescents in Flanders, Belgium.

Quantitative information on parents' preferences regarding multiple vaccine injections and on work-loss due to vaccination is important to guide decision making on the use of combination vaccines for universal vaccination. Our survey in families of 1347 toddlers (18 -- 24 months) and 1315 adolescents residing in Flanders, Belgium, revealed common attitudes in both age groups. The majority of parents would allow maximum two injections in one visit.

Using empirical social contact data to model person to person infectious disease transmission: an illustration for varicella.

With the aim to improve dynamic models for infections transmitted predominantly through non-sexual social contacts, we compared three popular model estimation methods in how well they fitted seroprevalence data and produced estimates for the basic reproduction number R(0) and the effective vaccination level required for elimination of varicella. For two of these methods, interactions between age groups were parameterized using empirical social contact data whereas for the third method we used the current standard approach of imposing a simplifying structure on the 'Who Acquires Infection From Whom' (WAIFW) matrix. The first method was based on solving a set of differential equations to obtain an equilibrium value of the proportion of susceptibles.

Mining social mixing patterns for infectious disease models based on a two-day population survey in Belgium.

Background: Until recently, mathematical models of person to person infectious diseases transmission had to make assumptions on transmissions enabled by personal contacts by estimating the so-called WAIFW-matrix. In order to better inform such estimates, a population based contact survey has been carried out in Belgium over the period March-May 2006. In contrast to other European surveys conducted simultaneously, each respondent recorded contacts over two days.

Prevaccination distribution of human papillomavirus types in women attending at cervical cancer screening in Belgium.

Introduction: Before the introduction of vaccination against human papillomaviruses (HPV) as a new strategy of combating cervical cancer, it is required to describe the baseline prevalence of HPV infection as well as the distribution of the different HPV types in the population and among women with cervical lesions.

Materials And Methods: Approximately 10,000 liquid cervical cell samples from women, resident of Flanders (North Belgium) and participating in cervical cancer screening, were assessed cytologically and virologically with a multiplex real-time PCR using primers targeting the E6/E7 genes of 16 HPV types. Correlations of HPV infection with age, geographic area, and occurrence of cytologic lesions were assessed.

Caregivers' willingness to pay to reduce the number of vaccine injections in infants.

As part of a larger face-to-face immunization coverage survey, 1347 families of infants (18-24 months) were questioned on their willingness to pay for a reduction in the number of concomitant vaccine injections. The median willingness to pay for a reduction by 1 injection was 5 EUR. The responses fell into 3 broad categories (willing to pay nothing at all, or anything, or a finite amount) and were hardly influenced by socioeconomic determinants.

Funding of drugs: do vaccines warrant a different approach?

Vaccines have features that require special consideration when assessing their cost-effectiveness. These features are related to herd immunity, quality-of-life losses in young children, parental care and work loss, time preference, uncertainty, eradication, macroeconomics, and tiered pricing. Advisory committees on public funding for vaccines, or for pharmaceuticals in general, should be knowledgable about these special features.

Cost-effectiveness of rotavirus vaccination: exploring caregiver(s) and "no medical care'' disease impact in Belgium.

Aim: To estimate the cost-effectiveness of universal childhood rotavirus vaccination in Belgium, taking into account the impact of caregiver burden and the burden of sick children for whom no medical care is sought ("no medical care'' ).

Methods: A cohort of newborns is modeled in relation to costs and health outcomes for rotavirus disease, distinguishing episodes leading to consultations, hospitalizations, and deaths from no medical care episodes. Fully funded universal vaccination is compared with no vaccination as well as with the current situation in Belgium, whereby the 2-dose Rotarix or the 3-dose RotaTeq vaccine can be bought at market prices, which are partially reimbursed.

Contact patterns and their implied basic reproductive numbers: an illustration for varicella-zoster virus.

The WAIFW matrix (Who Acquires Infection From Whom) is a central parameter in modelling the spread of infectious diseases. The calculation of the basic reproductive number (R0) depends on the assumptions made about the transmission within and between age groups through the structure of the WAIFW matrix and different structures might lead to different estimates for R0 and hence different estimates for the minimal immunization coverage needed for the elimination of the infection in the population. In this paper, we estimate R0 for varicella in Belgium.

Social contacts and mixing patterns relevant to the spread of infectious diseases.

Background: Mathematical modelling of infectious diseases transmitted by the respiratory or close-contact route (e.g., pandemic influenza) is increasingly being used to determine the impact of possible interventions.

The health and economic burden of rotavirus disease in Belgium.

For health economic evaluations of rotavirus vaccination, estimates of the health and cost burden of rotavirus are required. Due to differences in health care systems and surveillance organisations, this is difficult to achieve by imputing estimates from one country to others. This study aimed to estimate the burden of rotavirus disease in Belgium.

Precautionary behavior in response to perceived threat of pandemic influenza.

Faced with an epidemic of an infectious disease, persons may take precautionary actions to try to reduce their risk. Such actions include avoiding situations that persons perceive to be risky, which can have negative health and economic effects. Therefore, we conducted a population-based survey of persons' precautionary actions in response to a hypothetical influenza pandemic.

Partially wrong? Partial equilibrium and the economic analysis of public health emergencies of international concern.

We argue that traditional health economic analysis is ill-equipped to estimate the cost effectiveness and cost benefit of interventions that aim at controlling and/or preventing public health emergencies of international concern (such as pandemic influenza or severe acute respiratory syndrome). The implicit assumption of partial equilibrium within both the health sector itself and--if a wider perspective is adopted--the economy as a whole would be violated by such emergencies. We propose an alternative, with the specific aim of accounting for the behavioural changes and capacity problems that are expected to occur when such an outbreak strikes.

The cost-effectiveness of rotavirus vaccination in Australia.

Rotavirus is a common cause of acute gastroenteritis in young children. Two rotavirus vaccines with demonstrated safety and efficacy in large scale clinical trials have recently received universal funding in Australia. We modelled specific outcomes of disease (hospitalisations, emergency department visits, general practitioner visits, and deaths) and examined the effectiveness and cost-effectiveness of both vaccines in the Australian context.

Modelling multisera data: the estimation of new joint and conditional epidemiological parameters.

Testing humans for infectious diseases is often done by assessing the presence or absence of disease-specific antibodies in serum samples. For feasibility and economical reasons, these sera are often tested for more than one antigen. Studying diseases with similar transmission routes can govern new insights for disease dynamics.

Parvovirus B19 infection in five European countries: seroepidemiology, force of infection and maternal risk of infection.

We conducted a seroprevalence survey in Belgium, Finland, England & Wales, Italy and Poland on 13 449 serum samples broadly representative in terms of geography and age. Samples were tested for the presence of immunoglobulin G antibody using an enzyme immunoassay. The age-specific risk of infection was estimated using parametric and non-parametric statistical modelling.

Estimating the impact of vaccination using age-time-dependent incidence rates of hepatitis B.

The objective of this study was to model the age-time-dependent incidence of hepatitis B while estimating the impact of vaccination. While stochastic models/time-series have been used before to model hepatitis B cases in the absence of knowledge on the number of susceptibles, this paper proposed using a method that fits into the generalized additive model framework. Generalized additive models with penalized regression splines are used to exploit the underlying continuity of both age and time in a flexible non-parametric way.

Cost-effectiveness analyses of human papillomavirus vaccination.

With a human papillomavirus (HPV) vaccine soon to become available for widespread use, several studies have modelled the cost-effectiveness of vaccination. These pioneer studies are likely to be influential on the design of further analyses, and we have therefore summarised and critically reviewed the strengths and limitations of their methods and assumptions. Despite a lack of transparency in some key elements, the most influential assumptions were identified as relating to vaccine effectiveness, cervical screening, and model design.

Immunogenicity, efficacy, safety and effectiveness of pneumococcal conjugate vaccines (1998-2006).

In this paper we present an overview of the literature on efficacy and safety trials of the various pneumococcal conjugate vaccines on the market (PCV7) and in development (PCV9, PCV11 and allegedly PCV10 and PCV13), as well as of observations from post-licensure studies. Seven- (PCV7) and nine-valent PCV (PCV9) are reported to be sufficiently immunogenic after administration of a 3+1 schedule in infants in various RCTs. PncOMPC (PCV7 with a protein of N.

Convincing or confusing? Economic evaluations of childhood pneumococcal conjugate vaccination--a review (2002-2006).

We review 15 economic analyses of pneumococcal conjugate vaccines, published between 2002 and 2006, in terms of methodology, assumptions, results and conclusions. We found a great diversity in assumptions (eg, vaccine efficacy parameters, incidence rates for both invasive and non-invasive disease) mainly due to local variation in data and opinions. Accordingly, the results varied greatly, from total net savings to over euro 100,000 per discounted QALY gained.