Frequency and cost of live vaccines administered too soon after prior live vaccine in children aged 12 months through 6 years, 2014-2017.

OBJECTIVE: To identify number of children who received live vaccines outside recommended intervals between doses and calculate corrective revaccination costs. METHODS: We analyzed >1.6 million vaccination records for children aged 12 months through 6 years from six immunization information system (IIS) Sentinel Sites from 2014-15 when live attenuated influenza vaccine (LAIV, FluMist® Quadrivalent) was recommended for use, and from 2016-17, when not recommended for use. Depending on the vaccine, insufficient intervals between live vaccine doses are less than 24 or 28 days from a preceding live vaccine dose. Private and public purchase costs of vaccines were used to determine revaccination costs of live vaccine doses administered during the live vaccine conflict interval. Measles, mumps, rubella (MMR), varicella, combined MMRV, and LAIV were live vaccines evaluated in this study. RESULTS: Among 946,659 children who received at least one live vaccine dose from 2014-15, 4,873 (0.5%) received at least one dose too soon after a prior live vaccine (revaccination cost, $786,413) with a median conflict interval of 16 days. Among 704,591 children who received at least one live vaccine dose from 2016-17, 1,001 (0.1%) received at least one dose too soon after a prior live vaccine (revaccination cost, $181,565) with a median conflict interval of 14 days. The live vaccine most frequently administered outside of the recommended intervals was LAIV from 2014-15, and varicella from 2016-17. CONCLUSIONS: Live vaccine interval errors were rare (0.5%), indicating an adherence to recommendations. If all invalid doses were corrected by revaccination over the two time periods, the cost within the IIS Sentinel Sites would be nearly one million dollars. Provider awareness about live vaccine conflicts, especially with LAIV, could prevent errors, and utilization of clinical decision support functionality within IISs and Electronic Health Record Systems can facilitate better vaccination practices.

Budget Impact Analysis of Rotavirus Vaccine Adoption in the Childhood Immunization Schedule of Iran.

OBJECTIVES: To examine the budget impact of introducing the RotaTeq® vaccine (Merck and Co Inc, West Point, PA) to the national immunization program in Iran. METHODS: The pre- and postvaccine introduction costs were compared. The total annual costs included the vaccination and diarrhea treatment costs. The health outcome was the estimated annual cases of the disease. To evaluate the net budget impact, the annual prevaccine introduction cost was reduced from the postvaccine introduction cost. The sensitivity analysis was done to reduce the uncertainties. RESULTS: The total cost of vaccination for 5 years would be more than $184 million. Nevertheless, the financial savings would be about $45 million and $7.5 million because of the reduction in the number of patients after vaccination in inpatient and outpatient sectors, respectively. So the incremental cost would be $131 450 210 during 5 years of immunization. CONCLUSIONS: The results show that the inclusion of rotavirus vaccine in the national vaccination program would have a significant effect on health budgets and would raise government expenditure.

Cost-effectiveness of vaccination of immunocompetent older adults against herpes zoster in the Netherlands: a comparison between the adjuvanted subunit and live-attenuated vaccines.

BACKGROUND: The newly registered adjuvanted herpes zoster subunit vaccine (HZ/su) has a higher efficacy than the available live-attenuated vaccine (ZVL). National decision-makers soon need to decide whether to introduce HZ/su or to prefer HZ/su above ZVL. METHODS: Using a Markov model with a decision tree, we conducted a cost-effectiveness analysis of vaccination with HZ/su (two doses within 2 months) or zoster vaccine live (ZVL) (single dose, or single dose with a booster after 10 years) for cohorts of 50-, 60-, 70- or 80-year-olds in the Netherlands. The model was parameterized using vaccine efficacy data from randomized clinical trials and up-to-date incidence, costs and health-related quality of life data from national datasets. We used a time horizon of 15 years, and the analysis was conducted from the societal perspective. RESULTS: At a coverage of 50%, vaccination with two doses of HZ/su was estimated to prevent 4335 to 10,896 HZ cases, depending on the cohort age. In comparison, this reduction was estimated at 400-4877 for ZVL and 427-6466 for ZVL with a booster. The maximum vaccine cost per series of HZ/su to remain cost-effective to a willingness-to-pay threshold of €20,000 per quality-adjusted life year (QALY) gained ranged from €109.09 for 70-year-olds to €63.68 for 50-year-olds. The cost-effectiveness of ZVL changed considerably by age, with corresponding maximum vaccine cost per dose ranging from €51.37 for 60-year-olds to €0.73 for 80-year-olds. Adding a ZVL booster after 10 years would require a substantial reduction of the maximum cost per dose to remain cost-effective as compared to ZVL single dose. Sensitivity analyses on the vaccine cost demonstrated that there were scenarios in which vaccination with either HZ/su (two doses), ZVL single dose or ZVL + booster could be the most cost-effective strategy. CONCLUSIONS: A strategy with two doses of HZ/su was superior in reducing the burden of HZ as compared to a single dose or single dose + booster of ZVL. Both vaccines could potentially be cost-effective to a conventional Dutch willingness-to-pay threshold for preventive interventions. However, whether HZ/su or ZVL would be the most cost-effective alternative depends largely on the vaccine cost.

Benefit Versus Risk Assessment of Rotavirus Vaccination in France: A Simulation and Modeling Analysis.

INTRODUCTION: Two vaccines against rotavirus gastroenteritis (RVGE) in young children, Rotarix and RotaTeq, have been available in Europe since 2006. Vaccination against rotaviruses significantly reduces the burden of RVGE, but it is also associated with a very small increased risk of intussusception. In a benefit-risk analysis, the prevented RVGE burden is weighed against the possible excess of intussusception. PURPOSE: The aim was to compare the estimated benefits and risks of Rotarix vaccination in France. METHODS: We estimated the benefits (vaccine-preventable RVGE hospitalizations and deaths) and risks (vaccine-caused intussusception hospitalizations and deaths) following two doses of Rotarix in a birth cohort of 791,183 followed for 3-5 years in France. We used data from peer-reviewed clinical and epidemiological studies or publications, and government statistics. RESULTS: Within the total number of French children below 5 years of age, we estimate vaccination could prevent a median 11,132 [95% credible interval (CI) 7842-14,408] RVGE hospitalizations and 7.43 (95% CI 3.27-14.68) RVGE deaths. At the same time, vaccination could cause an average of 6.86 (95% CI 2.25-38.37) intussusception hospitalizations and 0.0099 (95% CI 0.0024-0.060) intussusception deaths in the entire French birth cohort of infants below 1 year of age. Therefore, for every intussusception hospitalization and every intussusception death caused by vaccination, 1624 (95% CI 240-5243) RVGE hospitalizations and 743 (95% CI 93-3723) RVGE deaths are prevented, respectively, by vaccination. CONCLUSIONS: The vaccine-prevented RVGE hospitalizations and deaths (benefit) greatly outweigh the excess potentially vaccination-related cases of intussusception (risk), indicating a favorable benefit-risk balance for Rotarix in France.

Vaccines for preventing influenza in healthy children.

BACKGROUND: The consequences of influenza in children and adults are mainly absenteeism from school and work. However, the risk of complications is greatest in children and people over 65 years of age. This is an update of a review published in 2011. Future updates of this review will be made only when new trials or vaccines become available. Observational data included in previous versions of the review have been retained for historical reasons but have not been updated because of their lack of influence on the review conclusions. OBJECTIVES: To assess the effects (efficacy, effectiveness, and harm) of vaccines against influenza in healthy children. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library 2016, Issue 12), which includes the Cochrane Acute Respiratory Infections Group Specialised Register, MEDLINE (1966 to 31 December 2016), Embase (1974 to 31 December 2016), WHO International Clinical Trials Registry Platform (ICTRP; 1 July 2017), and ClinicalTrials.gov (1 July 2017). SELECTION CRITERIA: Randomised controlled trials comparing influenza vaccines with placebo or no intervention in naturally occurring influenza in healthy children under 16 years. Previous versions of this review included 19 cohort and 11 case-control studies. We are no longer updating the searches for these study designs but have retained the observational studies for historical purposes. DATA COLLECTION AND ANALYSIS: Review authors independently assessed risk of bias and extracted data. We used GRADE to rate the certainty of evidence for the key outcomes of influenza, influenza-like illness (ILI), complications (hospitalisation, ear infection), and adverse events. Due to variation in control group risks for influenza and ILI, absolute effects are reported as the median control group risk, and numbers needed to vaccinate (NNVs) are reported accordingly. For other outcomes aggregate control group risks are used. MAIN RESULTS: We included 41 clinical trials (> 200,000 children). Most of the studies were conducted in children over the age of two and compared live attenuated or inactivated vaccines with placebo or no vaccine. Studies were conducted over single influenza seasons in the USA, Western Europe, Russia, and Bangladesh between 1984 and 2013. Restricting analyses to studies at low risk of bias showed that influenza and otitis media were the only outcomes where the impact of bias was negligible. Variability in study design and reporting impeded meta-analysis of harms outcomes.Live attenuated vaccinesCompared with placebo or do nothing, live attenuated influenza vaccines probably reduce the risk of influenza infection in children aged 3 to 16 years from 18% to 4% (risk ratio (RR) 0.22, 95% confidence interval (CI) 0.11 to 0.41; 7718 children; moderate-certainty evidence), and they may reduce ILI by a smaller degree, from 17% to 12% (RR 0.69, 95% CI 0.60 to 0.80; 124,606 children; low-certainty evidence). Seven children would need to be vaccinated to prevent one case of influenza, and 20 children would need to be vaccinated to prevent one child experiencing an ILI. Acute otitis media is probably similar following vaccine or placebo during seasonal influenza, but this result comes from a single study with particularly high rates of acute otitis media (RR 0.98, 95% CI 0.95 to 1.01; moderate-certainty evidence). There was insufficient information available to determine the effect of vaccines on school absenteeism due to very low-certainty evidence from one study. Vaccinating children may lead to fewer parents taking time off work, although the CI includes no effect (RR 0.69, 95% CI 0.46 to 1.03; low-certainty evidence). Data on the most serious consequences of influenza complications leading to hospitalisation were not available. Data from four studies measuring fever following vaccination varied considerably, from 0.16% to 15% in children who had live vaccines, while in the placebo groups the proportions ranged from 0.71% to 22% (very low-certainty evidence). Data on nausea were not reported.Inactivated vaccinesCompared with placebo or no vaccination, inactivated vaccines reduce the risk of influenza in children aged 2 to 16 years from 30% to 11% (RR 0.36, 95% CI 0.28 to 0.48; 1628 children; high-certainty evidence), and they probably reduce ILI from 28% to 20% (RR 0.72, 95% CI 0.65 to 0.79; 19,044 children; moderate-certainty evidence). Five children would need to be vaccinated to prevent one case of influenza, and 12 children would need to be vaccinated to avoid one case of ILI. The risk of otitis media is probably similar between vaccinated children and unvaccinated children (31% versus 27%), although the CI does not exclude a meaningful increase in otitis media following vaccination (RR 1.15, 95% CI 0.95 to 1.40; 884 participants; moderate-certainty evidence). There was insufficient information available to determine the effect of vaccines on school absenteeism due to very low-certainty evidence from one study. We identified no data on parental working time lost, hospitalisation, fever, or nausea.We found limited evidence on secondary cases, requirement for treatment of lower respiratory tract disease, and drug prescriptions. One brand of monovalent pandemic vaccine was associated with a sudden loss of muscle tone triggered by the experience of an intense emotion (cataplexy) and a sleep disorder (narcolepsy) in children. Evidence of serious harms (such as febrile fits) was sparse. AUTHORS' CONCLUSIONS: In children aged between 3 and 16 years, live influenza vaccines probably reduce influenza (moderate-certainty evidence) and may reduce ILI (low-certainty evidence) over a single influenza season. In this population inactivated vaccines also reduce influenza (high-certainty evidence) and may reduce ILI (low-certainty evidence). For both vaccine types, the absolute reduction in influenza and ILI varied considerably across the study populations, making it difficult to predict how these findings translate to different settings. We found very few randomised controlled trials in children under two years of age. Adverse event data were not well described in the available studies. Standardised approaches to the definition, ascertainment, and reporting of adverse events are needed. Identification of all global cases of potential harms is beyond the scope of this review.

Public health impact of Rotarix vaccination among commercially insured children in the United States.

BACKGROUND: This study (NCT01915888) assessed public health impact of Rotarix, GSK [RV1] vaccination. METHODS: Children born between 2007-2011 were identified from Truven Commercial Claims and Encounters Databases and observed until earlier of plan disenrollment or five years old. Children receiving one or two doses of RV1 during the vaccination window were assigned to incomplete and complete vaccination cohorts, respectively. Children without rotavirus (RV) vaccination (RV1 OR RotaTeq, Merck & Co., Inc. [RV5]) were assigned to the unvaccinated cohort. Claims with International Classification of Disease 9th edition (ICD-9) codes for diarrhea and RV infections were identified. First RV episode incidence, RV-related and diarrhea-related healthcare resource utilization were compared. Multivariate Poisson regression with generalized estimating equations was used to generate 95% confidence intervals (CIs) around incidence rate ratios (IRR) between cohorts while adjusting for gender, age and calendar year. Mean costs for first RV and diarrhea episodes were calculated with adjustment for gender and birth year; bootstrapping was used to determine statistically significant differences between cohorts. RESULTS: Incidence of first RV episodes was significantly reduced in complete and incomplete vaccination cohorts compared to the unvaccinated cohort (IRR=0.17 [95%CI: 0.09-0.30] and IRR=0.19 [95%CI: 0.06-0.58], respectively). RV-related inpatient, outpatient and emergency room (ER) visits were significantly lower for complete vaccination versus unvaccinated cohort. Diarrhea-related inpatient and ER visit rates were significantly lower for complete vaccination versus unvaccinated cohorts; outpatient rates were similar. RV-related and diarrhea-related resource utilization rates were significantly lower or no different for incomplete vaccination versus unvaccinated cohort. Compared with unvaccinated children, adjusted mean cost for first RV episode and first diarrhea episode per 1000 persons was $11,511 (95%CI: $9855-$12,024) and $46,772 (95%CI: $26,268-$66,604) lower, respectively, for completely vaccinated children. CONCLUSIONS: RV1 vaccination confers benefits in reduction of RV incidence, RV- and diarrhea-related healthcare resource utilization, and RV- and diarrhea-related healthcare costs.

Assessment of Public Health and Economic Impact of Intranasal Live-Attenuated Influenza Vaccination of Children in France Using a Dynamic Transmission Model.

OBJECTIVES: We estimated the epidemiological and economic impact of extending the French influenza vaccination programme from at-risk/elderly (≥65 years) only to healthy children (2-17 years). METHODS: A deterministic, age-structured, dynamic transmission model was used to simulate the transmission of influenza in the French population, using the current vaccination coverage with trivalent inactivated vaccine (TIV) in at-risk/elderly individuals (current strategy) or gradually extending the vaccination to healthy children (aged 2-17 years) with intranasal, quadrivalent live-attenuated influenza vaccine (QLAIV) from current uptake up to 50% (evaluated strategy). Epidemiological, medical resource use and cost data were taken from international literature and country-specific information. The model was calibrated to the observed numbers of influenza-like illness visits/year. The 10-year number of symptomatic cases of confirmed influenza and direct medical costs ('all-payer') were calculated for the 0-17- (direct and indirect effects) and ≥18-year-old (indirect effect). The incremental cost-effectiveness ratio (ICER) was calculated for the total population, using a 4% discount rate/year. RESULTS: Assuming 2.3 million visits/year and 1960 deaths/year, the model calibration yielded an all-year average basic reproduction number (R 0) of 1.27. In the population aged 0-17 years, QLAIV prevented 865,000 influenza cases/year (58.4%), preventing 10-year direct medical expenses of €374 million. In those aged ≥18 years with unchanged TIV coverage, 1.2 million cases/year were averted (27.6%) via indirect effects (additionally prevented expenses, €457 million). On average, 613 influenza-related deaths were averted annually overall. The ICER was €18,001/life-year gained. The evaluated strategy had a 98% probability of being cost-effective at a €31,000/life-year gained threshold. CONCLUSIONS: The model demonstrated strong direct and indirect benefits of protecting healthy children against influenza with QLAIV on public health and economic outcomes in France.

Coverage, efficacy or dosing interval: which factor predominantly influences the impact of routine childhood vaccination for the prevention of varicella? A model-based study for Italy.

BACKGROUND: Varicella is a highly infectious disease with a significant public health and economic burden, which can be prevented with childhood routine varicella vaccination. Vaccination strategies differ by country. Some factors are known to play an important role (number of doses, coverage, dosing interval, efficacy and catch-up programmes), however, their relative impact on the reduction of varicella in the population remains unclear. This paper aims to help policy makers prioritise the critical factors to achieve the most successful vaccination programme with the available budget. METHODS: Scenarios assessed the impact of different vaccination strategies on reduction of varicella disease in the population. A dynamic transmission model was used and adapted to fit Italian demographics and population mixing patterns. Inputs included coverage, number of doses, dosing intervals, first-dose efficacy and availability of catch-up programmes, based on strategies currently used or likely to be used in different countries. The time horizon was 30 years. RESULTS: Both one- and two-dose routine varicella vaccination strategies prevented a comparable number of varicella cases with complications, but two-doses provided broader protection due to prevention of a higher number of milder varicella cases. A catch-up programme in susceptible adolescents aged 10-14 years old reduced varicella cases by 27-43 % in older children, which are often more severe than in younger children. Coverage, for all strategies, sustained at high levels achieved the largest reduction in varicella. In general, a 20 % increase in coverage resulted in a further 27-31 % reduction in varicella cases. When high coverage is reached, the impact of dosing interval and first-dose vaccine efficacy had a relatively lower impact on disease prevention in the population. Compared to the long (11 years) dosing interval, the short (5 months) and medium (5 years) interval schedules reduced varicella cases by a further 5-13 % and 2-5 %, respectively. Similarly, a 10 % increase in first-dose efficacy (from 65 to 75 % efficacy) prevented 2-5 % more varicella cases, suggesting it is the least influential factor when considering routine varicella vaccination. CONCLUSIONS: Vaccination strategies can be implemented differently in each country depending on their needs, infrastructure and healthcare budget. However, ensuring high coverage remains the critical success factor for significant prevention of varicella when introducing varicella vaccination in the national immunisation programme.

A population based study comparing changes in rotavirus burden on the Island of Ireland between a highly vaccinated population and an unvaccinated population.

BACKGROUND: Rotavirus infection is a leading cause of gastroenteritis in infants and children globally. Reductions in rotavirus activity have been observed following introduction of rotavirus vaccination programmes, however a reductions have also been reported in some unvaccinated countries. The Island of Ireland incorporates the two jurisdictions Northern Ireland (NI) and the Republic of Ireland (IE). Both have similarities in climate, demography, morbidity and mortality but distinct health administrations and vaccination policies. Rotarix was added to the childhood immunisation programme in NI on the 1 July 2013. IE have not introduced routine rotavirus vaccination to date. The aim of this population based ecological study was to evaluate the impact of the rotavirus vaccine on burden of rotavirus disease in NI, and to compare with IE as an unvaccinated control population. This will help determine if the changes seen were due to the rotavirus vaccine, or due to confounding factors. METHODS: A number of population based measures of disease burden were compared in both jurisdictions pre-vaccine (six years; 2007/08-2012/13) and post-vaccine (two years; 2013/14-2014/15). The data sources included national rotavirus surveillance data based on laboratory reports/notifications; hospital admission data; and notifications of gastroenteritis in under 2year olds. RESULTS: In the post-vaccination period, rotavirus incidence in NI dropped by 54% while in IE it increased by 19% compared to the pre-vaccine period. Notifications of gastroenteritis in under 2s in NI declined by 53% and hospital admissions in under 5year olds in NI declined by 40% in the post vaccine period. CONCLUSIONS: This natural experiment demonstrated a significant reduction in rotavirus disease activity post-vaccine introduction in NI with associated reductions in healthcare utilisation, with a concurrent increase in rotavirus disease activity in the non-vaccinated population in IE. These findings support rotavirus vaccination as an effective measure to reduce childhood morbidity.

Assessment of safety and reproductive performance after vaccination with a modified live-virus PRRS genotype 1 vaccine in pregnant sows at various stages of gestation.

The objective of the present study was to assess safety and efficacy of a new modified live-virus porcine reproductive and respiratory syndrome (PRRS) genotype 1 vaccine in pregnant sows at various stages of gestation under field conditions. A total of 505 sows and gilts were allocated to two treatment groups and maintained in separate facilities. Animals of group 1 were vaccinated with a commercial modified live genotype 1 PRRSV vaccine (control product, CP), while animals of group 2 were immunized with a new modified live genotype 1 PRRSV vaccine (investigational veterinary product, IVP) (ReproCyc® PRRS EU, Boehringer Ingelheim Vetmedica GmbH). Injection site reactions were noted to be significantly less frequent in the IVP group compared to the CP group for pain (p=0.039), redness (p=0.030), heat (p=0.016) and swelling (p=0.002). The mean total number of piglets alive at weaning did not differ significantly between both study groups (10.6 vs. 11.0, p=0.375). However, pre-weaning mortality was significantly higher (p=0.005) in piglets from the CP group (14.1% vs. 10.9%). Analyses of reproductive performance data for both groups did not result in statistically significant differences between CP group and IVP group for number of piglets alive (12.7 and 12.6, respectively), healthy live (11.9 and 11.8), weak (0.7 and 0.5), stillborn (1.0 and 0.8) and mummified piglets (0.3 and 0.2) per litter. No differences were detected between both groups for piglet birth weights, while body weights at weaning (7.2kg vs. 6.6kg, p=0.026) and average daily gain (0.2445kg vs. 0.2211kg, p=0.037) were significantly higher in piglets from the IVP group. In conclusion, the administration of a single dose of ReproCyc® PRRS EU to sows and gilts at various stages of gestation confirmed non-inferiority to a commercial PRRS vaccine regarding safety and efficacy parameters under field conditions.

Assessment of the pathogenicity of cell-culture-adapted Newcastle disease virus strain Komarov.

Newcastle disease vaccines hitherto in vogue are produced from embryonated chicken eggs. Egg-adapted mesogenic vaccines possess several drawbacks such as paralysis and mortality in 2-week-old chicks and reduced egg production in the egg-laying flock. Owing to these possible drawbacks, we attempted to reduce the vaccine virulence for safe vaccination by adapting the virus in a chicken embryo fibroblast cell culture (CEFCC) system. Eighteen passages were carried out by CEFCC, and the pathogenicity was assessed on the basis of the mean death time, intracerebral pathogenicity index, and intravenous pathogenicity index, at equal passage intervals. Although the reduction in virulence demonstrated with increasing passage levels in CEFCC was encouraging, 20% of the 2-week-old birds showed paralytic symptoms with the virus vaccine from the 18(th)(final) passage. Thus, a tissue-culture-adapted vaccine would demand a few more passages by CEFCC in order to achieve a complete reduction in virulence for use as a safe and effective vaccine, especially among younger chicks. Moreover, it can be safely administered even to unprimed 8-week-old birds.

Assessment of the pathogenicity of cell-culture-adapted Newcastle disease virus strain Komarov

Newcastle disease vaccines hitherto in vogue are produced from embryonated chicken eggs. Egg-adapted mesogenic vaccines possess several drawbacks such as paralysis and mortality in 2-week-old chicks and reduced egg production in the egg-laying flock. Owing to these possible drawbacks, we attempted to reduce the vaccine virulence for safe vaccination by adapting the virus in a chicken embryo fibroblast cell culture (CEFCC) system. Eighteen passages were carried out by CEFCC, and the pathogenicity was assessed on the basis of the mean death time, intracerebral pathogenicity index, and intravenous pathogenicity index, at equal passage intervals. Although the reduction in virulence demonstrated with increasing passage levels in CEFCC was encouraging, 20% of the 2-week-old birds showed paralytic symptoms with the virus vaccine from the 18^th(final) passage. Thus, a tissue-culture-adapted vaccine would demand a few more passages by CEFCC in order to achieve a complete reduction in virulence for use as a safe and effective vaccine, especially among younger chicks. Moreover, it can be safely administered even to unprimed 8-week-old birds.

Cost effectiveness evaluation of a rotavirus vaccination program in Argentina.

BACKGROUND: Rotavirus diarrhea is one of the most important vaccine-preventable causes of severe diarrhea in children worldwide. There are two live-attenuated virus vaccines licensed, Rotarix (RV1) a monovalent vaccine by GlaxoSmithKline and a pentavalent vaccine, RotaTeq(RV5), by Merck & Co., with similar results. This study aim was to evaluate the cost-effectiveness of the utilization of RV1 compared with RV5 in Argentina. METHODS: A deterministic Markov model based on the lifetime follow up of a static cohort was used. Quality Adjusted Life Years (QALYs) as a measure of results, the perspective of the health care system and a 5% discount rate for health benefits and costs has been used. A review of the literature to obtain epidemiologic and resources utilization of rotavirus diarrhea was performed. The sources used to estimate epidemiologic parameters were the National Health Surveillance System, the national mortality statistics and national database of hospital discharges records. Costs were obtained from different health subsectors and are expressed in local currency. RESULTS: Both vaccination alternatives were less costly and more effective than the strategy without vaccination (total costs $ 69,700,645 and 2575 total QALYs lost). When comparing RV1 vs. RV5, RV1 was less expensive ($ 60,174,508 vs. $ 67,545,991 total costs) and more effective (1105 vs. 1213 total QALYs lost) than RV5, RV1 being therefore a dominating strategy. Probabilistic sensitivity analysis showed results to be robust with a 100% probability of being cost-effective at a WTP threshold of 1 GDP per capita when comparing the RV1 vs. no vaccination. CONCLUSION: Both RV1 and RV5 schedules dominate the no vaccination strategy and RV5 was dominated by RV1. This information is a valuable input regarding the incorporation of this kind of vaccines into the national vaccination programs.

In vivo assessment of equine arteritis virus vaccine improvement by disabling the deubiquitinase activity of papain-like protease 2.

Arteriviruses are a family of positive-stranded RNA viruses that includes the prototypic equine arteritis virus (EAV) and porcine reproductive and respiratory syndrome virus (PRRSV). Although several vaccines against these viruses are commercially available there is room for improvement, especially in the case of PRRSV. The ability of arteriviruses to counteract the immune response is thought to decrease the efficacy of the current modified live virus vaccines. We have recently shown that the deubiquitinase (DUB) activity of EAV papain-like protease 2 (PLP2) is important for the inhibition of innate immune activation during infection. A vaccine virus lacking PLP2 DUB activity may therefore be more immunogenic and provide improved protection against subsequent challenge than its DUB-competent counterpart. To test this hypothesis, twenty Shetland mares were randomly assigned to one of three groups. Two groups were vaccinated, either with DUB-positive (n=9) or DUB-negative (n=9) recombinant EAV. The third group (n=2) was not vaccinated. All horses were subsequently challenged with the virulent KY84 strain of EAV. Both vaccine viruses proved to be replication competent in vivo. In addition, the DUB-negative virus provided a similar degree of protection against clinical disease as its DUB-positive parental counterpart. Owing to the already high level of protection provided by the parental virus, a possible improvement due to inactivation of PLP2 DUB activity could not be detected under these experimental conditions. Taken together, the data obtained in this study warrant further in vivo investigations into the potential of using DUB-mutant viruses for the improvement of arterivirus vaccines.

Effectiveness of rotavirus vaccines, licensed but not funded, against rotavirus hospitalizations in the Valencia Region, Spain.

BACKGROUND: Although rotavirus vaccines have been licensed in Spain for over 8 years, they are not funded by its public health systems. The analysis of their effectiveness in the Valencia Region could better inform decisions about potential inclusion in the official immunization schedule. Our aim was to assess the effectiveness of Rotarix® (RV1) and RotaTeq® (RV5) against rotavirus hospitalizations. METHODS: We conducted a retrospective cohort study using the region's health care databases, among resident children aged <3 years covered by the National Health System, during January 2007-June 2012. We compared two cohorts of vaccinated children: the first included children who received at least one dose of a rotavirus vaccine, and the second included children who were not vaccinated with rotavirus vaccines but received at least one dose of a pneumococcal vaccine, another licensed but non-funded vaccine. The main outcome was rotavirus hospitalization, either laboratory-confirmed (confirmed) or codified as rotavirus (probable). Rotavirus vaccine effectiveness (RVE) by vaccine brand was assessed using Cox proportional hazards models. RESULTS: The study included 78,281 rotavirus and 96,643 pneumococcal vaccinees. Adjusted RVE against probable or confirmed rotavirus hospitalizations was 86% (95% CI: 78-91%) and 88% (95% CI: 81-92%) for a complete series of RV1 and RV5 respectively. CONCLUSIONS: Both rotavirus vaccines were over 85% effective against rotavirus hospitalization among young children. The high effectiveness shown argues in favor of their inclusion in the official schedule. Additional information on rotavirus vaccine safety, duration of protection, and benefit-risk will also be needed to inform such deliberations.

Assessment of bivalent and tetravalent dengue vaccine formulations in flavivirus-naïve adults in Mexico.

UNLABELLED: Several ChimeriVax-Dengue (CYD)-based vaccination strategies were investigated as potential alternatives to vaccination with tetravalent CYD vaccine (CYD-TDV) in this phase IIa trial conducted in 2008-9 in 150 healthy adults. Participants were randomized and vaccinated on D0 and D105 (± 15 days). One group received bivalent CYD vaccine against serotypes 1 and 3 (CYD-1;3) on day 0 and CYD-2;4 on day 105 (± 15 days). Two groups received an injection at each timepoint of a tetravalent blend of CYD-1;3;4 and a VERO cell derived, live attenuated vaccine against serotype 2 (VDV-2), or the reference CYD-TDV. A fourth group received Japanese encephalitis (JE) vaccine on days -14, -7 and 0, followed by CYD-TDV on day 105. Viraemia was infrequent in all groups. CYD-4 viraemia was most frequent after tetravalent vaccination, while CYD-3 viraemia was most frequent after the first bivalent vaccination. Immunogenicity as assessed by 50% plaque reduction neutralisation test on D28 was comparable after the first injection of either tetravalent vaccine, and increased after the second injection, particularly with the blended CYD-1;3;4/ VDV-2 vaccine. In the bivalent vaccine group, immune response against serotype 3 was highest and the second injection elicited a low immune response against CYD 2 and 4. Immune responses after the first injection of CYD-TDV in the JE-primed group were in general higher than after the first injection in the other groups. All tested regimens were well tolerated without marked differences between groups. Bivalent vaccination showed no advantage in terms of immunogenicity. CLINICAL TRIAL REGISTRATION NUMBER: NCT00740155.

Parents' preferences for seasonal influenza vaccine for their children in Japan.

In Japan, trivalent inactivated influenza vaccine is the only approved influenza vaccine. It is typically administrated by hypodermic injection, and children under 13 years of age are recommended to be vaccinated two times during each winter season. Live-attenuated influenza vaccine (LAIV) is administered by a thimerosal-free nasal spray. If LAIV is approved in the future in Japan, parents will have an alternative type of influenza vaccine for their children. This study investigated parents' preference for the type of seasonal influenza vaccine for their children if alternatives are available. The marginal willingness to pay for vaccine benefits was also evaluated. We conducted a discrete choice experiment, a quantitative approach that is often used in healthcare studies, in January 2013. Respondents were recruited from a registered online survey panel, and parents with at least one child under 13 years of age were offered questionnaires. This study showed that for seasonal influenza vaccines for their children, parents are more likely to value safety, including thimerosal-free vaccines and those with a lower risk of adverse events, instead of avoiding the momentary pain from an injection. If LAIV is released in Japan, the fact that it is thimerosal-free could be an advantage. However, for parents to choose LAIV, they would need to accept the slightly higher risk of minor adverse events from LAIV.

Evaluating the potential risks and benefits of infant rotavirus vaccination in England.

Rotarix(®), a vaccine for the prevention of gastroenteritis in young children, was introduced in England in July 2013. At around this time, an elevated risk of intussusception (a cause of bowel obstruction) was reported among infants vaccinated in Australia and the USA. A risk-benefit analysis compared potential vaccine-related risks (additional intussusception admissions and deaths) with estimated vaccine benefits (prevented rotavirus general practitioner visits, emergency visits, admissions and deaths) in the 2012 birth cohort. Detailed data from England included the incidence of intussusception events aged <2 years by week of age, the coverage of vaccination aged <2 years by week of age, and the incidence of rotavirus gastroenteritis (RVGE) events aged <5 years by week of age. Recent estimates of vaccine-related risk from Australia were applied during the 1-21 day period after the first and second dose of vaccination. Rotarix(®) is estimated to cause one additional intussusception admission in every 18,551 vaccinated English infants (5th and 95th percentiles, 6728-93,952), equivalent to 35 (7-98) additional intussusception admissions each year. The vaccine is estimated to prevent three rotavirus deaths, 13,000 rotavirus admissions, 27,000 rotavirus emergency visits and 74,000 rotavirus GP consultations in children aged <5 years, and lead to annual savings of over £11 million, each year. We estimate 375 (136-1900) fewer RVGE admissions for every additional intussusception admission, and 88 (18-852) fewer RVGE deaths for every additional intussusception death. The estimated benefits of Rotarix(®) vaccination would greatly exceed the potential risk in England.

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.