Cost-Effectiveness of Routine Childhood Vaccination Against Seasonal Influenza in Germany.

OBJECTIVES: In Germany, routine influenza vaccination with quadrivalent influenza vaccines (QIV) is recommended and reimbursed for individuals ≥60 years of age and individuals with underlying chronic conditions. The present study examines the cost-effectiveness of a possible extension of the recommendation to include strategies of childhood vaccination against seasonal influenza using QIV. METHODS: A dynamic transmission model was used to examine the epidemiological impact of different childhood vaccination strategies. The outputs were used in a health economic decision tree to calculate the costs per quality-adjusted life year (QALY) gained from a societal and a third-party payer (TPP) perspective. Strain-specific epidemiology, vaccine uptake, and vaccine efficacy data from the 10 non-pandemic seasons from 2003/2004 to 2013/2014 were used, and cost data were drawn mainly from a health insurance claims data analysis and supplemented by estimates from literature. Uncertainty is explored via scenario, deterministic, and probabilistic sensitivity analyses. RESULTS: Vaccinating 2- to 9-year-olds with QIV assuming a vaccine uptake of 40% is cost-saving with a benefit-cost ratio of 1.66 from a societal perspective and an incremental cost-effectiveness ratio of €998/QALY from a TPP perspective. Lower and higher vaccine uptakes show marginal effects, while extending the target group to 2- to 17-year-olds further increases the health benefits while still being below the willingness-to-pay (WTP) threshold. Assuming no vaccine-induced herd protection has a negative effect on the cost-effectiveness ratio, but childhood vaccination remains cost-effective. CONCLUSION: Routine childhood vaccination against seasonal influenza in Germany is most likely to be cost-saving from a societal perspective and highly cost-effective from a TPP perspective.

Hyperlipidemias in elderly patients: results from the Berlin Aging Study II (BASEII), a cross-sectional study.

BACKGROUND: Hyperlipidemias are common and the last decades have seen substantially growing evidence of their causative role in the development of atherosclerosis and subsequent cardiovascular diseases. Since hyperlipidemias usually do not cause direct clinical symptoms, they often remain undiagnosed until a serious cardiovascular event occurs. Especially for LDL-hypercholesteremia, there are well-established treatment options available to prevent the occurrence of atherosclerosis. However, there is a lack of knowledge regarding the proper treatment of elderly patients. The goal of this study was to assess the prevalence of hyperlipidemia in a group of young and a group of elderly community-dwelling participants and to determine to what extent treatment of hyperlipidemia should be initiated or required. METHODS: Crossectional data from a total of 2151 subjects (1657 in the elderly group, mean age 69, and 494 in the young group (control group), mean age 29) of the Berlin Aging Study II (BASE-II) were available. Medical history was assessed and recorded by trained physicians and prevalence of lipid disorders was determined with laboratory tests, including a lipid-profile. RESULTS: A large proportion of subjects (39%) were unaware of an existing lipid disorder. The prevalence of hyperlipidemia was more frequent in the elderly group (76%) compared to the young group (41%). Hypercholesterolemia was the most common diagnosed disorder (64%), followed by hyperlipoproteinemia(a) (18%), hypertriglyceridemia (7%) and combined hyperlipoproteinaemia (5%). Only a minority of this cohort was treated with lipid-lowering medication (17%) and of those treatment targets according to ESC guidelines were reached only in 16.5 %. CONCLUSIONS: Hyperlipidemias appear underdiagnosed and undertreated. As the prevalence of these disorders increases with age and with regard to their role as a major modifiable risk factor for cardiovascular disease it seems to be advisable to aim for more consistent and sustainable screening and treatment of these common disorders. TRIAL REGISTRATION: BASE-II registered with the clinical trial registry Deutsches Register Klinischer Studien (DRKS00009277).

Group B Streptococci: Declining Incidence in Infants in Germany.

Group B streptococcus (GBS) is a leading cause of morbidity and mortality in newborns worldwide. From 2000 to 2008, national guidelines in Germany recommended intrapartum antibiotic prophylaxis for pregnant women displaying risk factors (eg, perinatal anogenital GBS colonization, rupture of the membranes ≥18 hours before birth) for the vertical transmission of GBS to their children. In 2008, these guidelines were revised to advocate universal, culture-based screening for GBS colonization among all pregnant women between 35 and 37 weeks of gestation. For the period 2009-2010, our prospective active surveillance study assessed the incidence of invasive GBS infections in infants 0-90 days of age in Germany. We did this by means of a capture-recapture analysis of 2 separate, independent systems (pediatric reporting versus laboratory reporting). We compared our results with those from a previous study by employing an equivalent design (2001-2003). We detected a 32% reduction in GBS incidence, from 0.47 per 1000 live births (n = 679) in 2001-2003 to 0.34 per 1000 live births (n = 450) in 2009-2010. This decline primarily is tied to a reduced number of GBS cases in children under 1 week of age. In 2009-2010, the ratio of early-onset disease to late-onset disease reversed from 1.52 (206:136), as determined in 2001-2003, to 0.75 (92:122). This study is the first to assess changes in the incidence of invasive GBS in Germany after the implementation of the guidelines for intrapartum prophylaxis for pregnant women colonized with GBS.

Influence of demographic changes on the impact of vaccination against varicella and herpes zoster in Germany - a mathematical modelling study.

BACKGROUND: Epidemiological studies suggest that reduced exposure to varicella might lead to an increased risk for herpes zoster (HZ). Reduction of exposure to varicella is a consequence of varicella vaccination but also of demographic changes. We analyzed how the combination of vaccination programs and demographic dynamics will affect the epidemiology of varicella and HZ in Germany over the next 50 years. METHODS: We used a deterministic dynamic compartmental model to assess the impact of different varicella and HZ vaccination strategies on varicella and HZ epidemiology in three demographic scenarios, namely the projected population for Germany, the projected population additionally accounting for increased immigration as observed in 2015/2016, and a stationary population. RESULTS: Projected demographic changes alone result in an increase of annual HZ cases by 18.3% and a decrease of varicella cases by 45.7% between 1990 and 2060. Independently of the demographic scenario, varicella vaccination reduces the cumulative number of varicella cases until 2060 by approximately 70%, but also increases HZ cases by 10%. Unlike the currently licensed live attenuated HZ vaccine, the new subunit vaccine candidate might completely counteract this effect. Relative vaccine effects were consistent across all demographic scenarios. CONCLUSION: Demographic dynamics will be a major determinant of HZ epidemiology in the next 50 years. While stationary population models are appropriate for assessing vaccination impact, models incorporating realistic population structures allow a direct comparison to surveillance data and can thus provide additional input for immunization decision-making and resource planning.

Analysing published global Ebola Virus Disease research using social network analysis.

INTRODUCTION: The 2014/2015 West African Ebola Virus Disease (EVD) outbreak attracted global attention. Numerous opinions claimed that the global response was impaired, in part because, the EVD research was neglected, although quantitative or qualitative studies did not exist. Our objective was to analyse how the EVD research landscape evolved by exploring the existing research network and its communities before and during the outbreak in West Africa. METHODS/ PRINCIPAL FINDINGS: Social network analysis (SNA) was used to analyse collaborations between institutions named by co-authors as affiliations in publications on EVD. Bibliometric data of publications on EVD between 1976 and 2015 was collected from Thomson Reuters' Web of Science Core Collection (WoS). Freely available software was used for network analysis at a global-level and for 10-year periods. The networks are presented as undirected-weighted graphs. Rankings by degree and betweenness were calculated to identify central and powerful network positions; modularity function was used to identify research communities. Overall 4,587 publications were identified, of which 2,528 were original research articles. Those yielded 1,644 authors' affiliated institutions and 9,907 connections for co-authorship network construction. The majority of institutions were from the USA, Canada and Europe. Collaborations with research partners on the African continent did exist, but less frequently. Around six highly connected organisations in the network were identified with powerful and broker positions. Network characteristics varied widely among the 10-year periods and evolved from 30 to 1,489 institutions and 60 to 9,176 connections respectively. Most influential actors are from public or governmental institutions whereas private sector actors, in particular the pharmaceutical industry, are largely absent. CONCLUSION/ SIGNIFICANCE: Research output on EVD has increased over time and surged during the 2014/2015 outbreak. The overall EVD research network is organised around a few key actors, signalling a concentration of expertise but leaving room for increased cooperation with other institutions especially from affected countries. Finding innovative ways to maintain support for these pivotal actors while steering the global EVD research network towards an agenda driven by agreed, prioritized needs and finding ways to better integrate currently peripheral and newer expertise may accelerate the translation of research into the development of necessary live saving products for EVD ahead of the next outbreak.

Is the impact of childhood influenza vaccination less than expected: a transmission modelling study.

BACKGROUND: To reduce the burden of severe influenza, most industrialized countries target specific risk-groups with influenza vaccines, e.g. the elderly or individuals with comorbidities. Since children are the main spreaders, some countries have recently implemented childhood vaccination programs to reduce overall virus transmission and thereby influenza disease in the whole population. The introduction of childhood vaccination programs was often supported by modelling studies that predicted substantial incidence reductions. We developed a mathematical transmission model to examine the potential impact of childhood influenza vaccination in Germany, while also challenging established modelling assumptions. METHODS: We developed an age-stratified SEIR-type transmission model to reproduce the epidemic influenza seasons between 2003/04 and 2013/14. The model was built upon German population counts, contact patterns, and vaccination history and was fitted to seasonal data on influenza-attributable medically attended acute respiratory infections (I-MAARI) and strain distribution using Bayesian methods. As novelties we (i) implemented a stratified model structure enabling seasonal variability and (ii) deviated from the commonly assumed mass-action-principle by employing a phenomenological transmission rate. RESULTS: According to the model, by vaccinating primarily the elderly over ten seasons 4 million (95% prediction interval: 3.84 - 4.19) I-MAARI were prevented which corresponds to an 8.6% (8.3% - 8.9%) reduction compared to a no-vaccination scenario and a number-needed-to-vaccinate (NNV) to prevent one I-MAARI of 37.1 (35.5 - 38.7). Additional vaccination of 2-10 year-old children at 40% coverage would have led to an overall I-MAARI reduction of 17.8% (17.1 - 18.7%) mostly due to indirect effects with a NNV of 20.7 (19.6 - 21.6). When employing the traditional mass-action-principle, the model predicted a more than 3-fold higher I-MAARI reduction (55.6%) due to childhood vaccination. CONCLUSION: In Germany, the introduction of routine childhood influenza vaccination could considerably reduce I-MAARI among all age-groups and improve the NNV. However, the predicted impact is much lower compared to previous studies, which is primarily caused by our phenomenological approach to modelling influenza virus transmission.

Epidemiological impact and cost-effectiveness of universal vaccination with Bexsero(®) to reduce meningococcal group B disease in Germany.

Bexsero, a new vaccine against serogroup B meningococcal disease (MenB), was licensed in Europe in January 2013. In Germany, Bexsero is recommended for persons at increased risk of invasive meningococcal disease, but not for universal childhood vaccination. To support decision making we adapted the independently developed model for England to the German setting to predict the potential health impact and cost-effectiveness of universal vaccination with Bexsero(®) against MenB disease. We used both cohort and transmission dynamic mathematical models, the latter allowing for herd effects, to consider the impact of vaccination on individuals aged 0-99 years. Vaccination strategies included infant and adolescent vaccination, alone or in combination, and with one-off catch-up programmes. German specific data were used where possible from routine surveillance data and the literature. We assessed the impact of vaccination through cases averted and quality adjusted life years (QALY) gained and calculated costs per QALY gained. Assuming 65% vaccine uptake and 82% strain coverage, infant vaccination was estimated to prevent 15% (34) of MenB cases over the lifetime of one birth cohort. Including herd effects from vaccination increased the cases averted by infant vaccination to 22%, with an estimated 8461 infants requiring vaccination to prevent one case. In the short term the greatest health benefit is achieved through routine infant vaccination with large-scale catch-up, which could reduce cases by 24.9% after 5 years and 27.9% after 10 years. In the long term (20+ years) policies including routine adolescent vaccination are most favourable if herd effects are assumed. Under base case assumptions with a vaccine list price of €96.96 the incremental cost-effectiveness ratio (ICER) was >€500,000 per QALY for all considered strategies. Given the current very low incidence of MenB disease in Germany, universal vaccination with Bexsero(®) would prevent only a small absolute number of cases, at a high overall cost.

Current and future effects of varicella and herpes zoster vaccination in Germany - Insights from a mathematical model in a country with universal varicella vaccination.

Varicella zoster virus (VZV) is primarily known for causing varicella in childhood, but can reactivate again as herpes zoster (HZ) after a period of latency, mainly in persons older than 50 years. Universal varicella vaccination was introduced in Germany in 2004, while HZ vaccination has not been recommended yet. We aimed to quantify the potential long-term effects of universal childhood varicella vaccination and HZ vaccination of the elderly on varicella and HZ incidence in Germany over a time horizon of 100 years, using a transmission model calibrated to pre-vaccination data and validated against early post-vaccination data. Using current vaccination coverage rates of 87% (64%) with one (two) varicella vaccine dose(s), the model predicts a decrease in varicella cases by 89% for the year 2015. In the long run, the incidence reduction will stabilize at about 70%. Under the assumption of the boosting hypothesis of improved HZ protection caused by exposure to VZV, the model predicts a temporary increase in HZ incidence of up to 20% for around 50 years. HZ vaccination of the elderly with an assumed coverage of 20% has only limited effects in counteracting this temporary increase in HZ incidence. However, HZ incidence is shown to decrease in the long-term by 58% as vaccinated individuals get older and finally reach age-classes with originally high HZ incidence. Despite substantial uncertainties around several key variables, the model's results provide valuable insights that support decision-making regarding national VZV vaccination strategies.

Modelling the epidemiological impact of rotavirus vaccination in Germany--a Bayesian approach.

BACKGROUND: Rotavirus (RV) infection is the primary cause of severe gastroenteritis in children aged <5 years in Germany and worldwide. In 2013 the German Standing Committee on Vaccination (STIKO) developed a national recommendation for routine RV-immunization of infants. To support informed decision-making we predicted the epidemiological impact of routine RV-vaccination in Germany using statistical modelling. METHODS: We developed a population-based model for the dynamic transmission of RV-infection in a vaccination setting. Using data from the communicable disease reporting system and survey records on the vaccination coverage from the eastern federal states, where the vaccine was widely used before recommended at national level, we first estimated RV vaccine effectiveness (VE) within a Bayesian framework utilizing adaptive Markov Chain Monte Carlo inference. The calibrated model was then used to compute the predictive distribution of RV-incidence after achieving high vaccination coverage with the introduction of routine vaccination. RESULTS: Our model estimated that RV-vaccination provides high protection against symptomatic RV-infection (VE=96%; 95% credibility interval (CI): 91-99%) that remains at its maximum level for three years (95% CI: 1.43-5.80 years) and is fully waned after twelve years. At population level, routine vaccination at 90% coverage is predicted to reduce symptomatic RV-incidence among children aged <5 years by 84% (95% prediction interval (PI): 71-90%) including a 2.5% decrease due to herd protection. Ten years after vaccine introduction an increase in RV incidences of 12% (95% PI: -16 to 85%) among persons aged 5-59 years and 14% (95% PI: -6 to 109%) within the age-group >60 years was predicted. CONCLUSION: Routine infant RV-vaccination is predicted to considerably reduce RV-incidence in Germany among children <5 years. Our work generated estimates of RV VE in the field and predicted the population-level impact, while adequately addressing the role of model and prediction uncertainty when making statements about the future.

Bayesian parameter inference for dynamic infectious disease modelling: rotavirus in Germany.

Understanding infectious disease dynamics using epidemic models based on ordinary differential equations requires the calibration of model parameters from data. A commonly used approach in practice to simplify this task is to fix many parameters on the basis of expert or literature information. However, this not only leaves the corresponding uncertainty unexamined but often also leads to biased inference for the remaining parameters because of dependence structures inherent in any given model. In the present work, we develop a Bayesian inference framework that lessens the reliance on such external parameter quantifications by pursuing a more data-driven calibration approach. This includes a novel focus on residual autocorrelation combined with model averaging techniques in order to reduce these estimates' dependence on the underlying model structure. We applied our methods to the modelling of age-stratified weekly rotavirus incidence data in Germany from 2001 to 2008 using a complex susceptible-infectious-susceptible-type model complemented by the stochastic reporting of new cases. As a result, we found the detection rate in the eastern federal states to be more than four times higher compared with that of the western federal states (19.0% vs 4.3%), and also the infectiousness of symptomatically infected individuals was estimated to be more than 10 times higher than that of asymptomatically infected individuals (95% credibility interval: 8.1­19.6). Not only do these findings give valuable epidemiological insight into the transmission processes, we were also able to examine the considerable impact on the model-predicted transmission dynamics when fixing parameters beforehand.

Cost-effectiveness of childhood rotavirus vaccination in Germany.

BACKGROUND: Rotavirus (RV) causes a highly contagious gastroenteritis especially in children under five years of age. Since 2006 two RV-vaccines are available in Europe (Rotarix(®) and RotaTeq(®)). To support informed decision-making within the German Standing Committee on Vaccination (STIKO) the cost-effectiveness of these two vaccines was evaluated for the German healthcare setting. METHODS: A Markov model was developed to evaluate the cost-effectiveness from the statutory health insurance (SHI) and from the societal perspective. RV-cases prevented, RV-associated hospitalizations avoided, and quality-adjusted life years (QALY) gained were considered as health outcomes. RV-incidences were calculated based on data from the national mandatory disease reporting system. RV-vaccine efficacy was determined as pooled estimates based on data from randomized controlled trials. Vaccine list prices and price catalogues were used for cost-assessment. Effects and costs were discounted with an annual discount rate of 3%. RESULTS: The base-case analysis (SHI-perspective) resulted in an incremental cost-effectiveness and cost-utility ratio for Rotarix(®) of € 184 per RV-case prevented, € 2457 per RV-associated hospitalization avoided, and € 116,973 per QALY gained. For RotaTeq(®), the results were € 234 per RV-case prevented, € 2622 per RV-associated hospitalization avoided, and € 142,732 per QALY gained. Variation of various parameters in sensitivity analyses showed effects on the ICERs without changing the overall trend of base-case results. When applying base-case results to the 2012 birthcohort in Germany with 80% vaccination coverage, an estimated 206,000-242,000 RV-cases and 18,000 RV-associated hospitalizations can be prevented in this birthcohort over five years for an incremental cost of 44.5-48.2 million €. CONCLUSION: Our analyses demonstrate that routine RV-vaccination could prevent a substantial number of RV-cases and hospitalizations in the German healthcare system, but the saved treatment costs are counteracted by costs for vaccination. However, with vaccine prices reduced by ∼62-66%, RV-vaccination could even become a cost-saving preventive measure.

Health economic evaluation of vaccination strategies for the prevention of herpes zoster and postherpetic neuralgia in Germany.

BACKGROUND: Herpes zoster (HZ) is a self-limiting painful skin rash affecting mostly individuals from 50 years of age. The main complication is postherpetic neuralgia (PHN), a long-lasting pain after rash has resolved. A HZ-vaccine has recently been licensed in Europe for individuals older than 50 years. To support an informed decision-making for a potential vaccination recommendation, we conducted a health economic evaluation to identify the most cost-effective vaccination strategy. METHODS: We developed a static Markov-cohort model, which compared a vaccine-scenario with no vaccination. The cohort entering the model was 50 years of age, vaccinated at age 60, and stayed over life-time in the model. Transition probabilities were based on HZ/PHN-epidemiology and demographic data from Germany, as well as vaccine efficacy (VE) data from clinical trials. Costs for vaccination and HZ/PHN-treatment (in Euros; 2010), as well as outcomes were discounted equally with 3% p.a. We accounted results from both, payer and societal perspective. We calculated benefit-cost-ratio (BCR), number-needed-to-vaccinate (NNV), and incremental cost-effectiveness ratios (ICERs) for costs per HZ-case avoided, per PHN-case avoided, and per quality-adjusted life-year (QALY) gained. Different target age-groups were compared to identify the most cost-effective vaccination strategy. Base-case-analysis as well as structural, descriptive-, and probabilistic-sensitivity-analyses (DSA, PSA) were performed. RESULTS: When vaccinating 20% of a cohort of 1 million 50 year old individuals at the age of 60 years, approximately 20,000 HZ-cases will be avoided over life-time. The NNV to avoid one HZ (PHN)-case was 10 (144). However, with a BCR of 0.34 this vaccination-strategy did not save costs. The base-case-analysis yielded an ICER of 1,419 (20,809) Euros per avoided HZ (PHN)-case and 28,146 Euros per QALY gained. Vaccination at the age of 60 was identified in most (sensitivity) analyses to be the most cost-effective vaccination strategy. In DSA, vaccine price and VE were shown to be the most critical input-data. CONCLUSIONS: According to our evaluation, HZ-vaccination is expected to avoid HZ/PHN-cases and gain QALYs to higher costs. However, the vaccine price had the highest impact on the ICERs. Among different scenarios, targeting individuals aged 60 years seems to represent the most cost-effective vaccination-strategy.