Article

Influence of timing of seasonal influenza vaccination on effectiveness and cost-effectiveness in pregnancy

Division of Clinical and Epidemiological Research, Department of Obstetrics & Gynecology, Duke University Medical Center, Durham, NC, USA.
American journal of obstetrics and gynecology (Impact Factor: 3.97). 06/2011; 204(6 Suppl 1):S128-40. DOI: 10.1016/j.ajog.2011.04.009
Source: PubMed

ABSTRACT The purpose of this review was to estimate the impact of timing of seasonal influenza vaccination during pregnancy on health and economic outcomes. Cost-effectiveness analysis with a dynamic model of the US population of pregnant women and infants who were <6 months incorporated seasonal variation in influenza incidence. Compared with no vaccination, seasonal influenza vaccination in pregnancy costs $70,089 per quality-adjusted life year. Most of the benefit for infants was limited to those whose mothers were vaccinated within the first 4 weeks of vaccine availability. Once all women who were pregnant at the time of vaccine availability were vaccinated, vaccination of newly pregnant women had benefits for mothers but not infants. Delay of vaccination beyond November reduced both effectiveness and cost-effectiveness. The greatest population benefit from seasonal influenza vaccination in pregnancy was realized if pregnant women were vaccinated as soon as possible after trivalent inactivated influenza vaccine became available. Efforts to increase vaccine rates should be concentrated early in the influenza season.

0 Followers
 · 
81 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: Risk groups with increased vulnerability for influenza complications such as pregnant women, persons with underlying illnesses as well as persons who come into contact with them, such as health care workers, are currently given priority (along with other classic target groups) to receive seasonal influenza vaccination in Belgium. We aimed to evaluate this policy from a health care payer perspective by cost-effectiveness analysis in the three specific target groups above, while accounting for effects beyond the target group. Increasing the coverage of influenza vaccination is likely to be cost-effective for pregnant women (median €6589 per quality-adjusted life-year (QALY) gained [€4073-€10,249]) and health care workers (median €24,096/QALY gained [€16,442-€36,342]), if this can be achieved without incurring additional administration costs. Assuming an additional physician's consult is charged to administer each additional vaccine dose, the cost-effectiveness of vaccinating pregnant women depends strongly on the extent of its impact on the neonate's health. For health care workers, the assumed number of preventable secondary infections has a strong influence on the cost-effectiveness. Vaccinating people with underlying illnesses is likely highly cost-effective above 50 years of age and borderline cost-effective for younger persons, depending on relative life expectancy and vaccine efficacy in this risk group compared to the general population. The case-fatality ratios of the target group, of the secondary affected groups and vaccine efficacy are key sources of uncertainty.
    Vaccine 09/2014; 32(46). DOI:10.1016/j.vaccine.2014.08.085 · 3.49 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Objectives. We evaluated the impact of influenza vaccine text message reminders in a low-income obstetric population. Methods. We conducted a randomized controlled trial that enrolled 1187 obstetric patients from 5 community-based clinics in New York City. The intervention group received 5 weekly text messages regarding influenza vaccination starting mid-September 2011 and 2 text message appointment reminders. Both groups received standard automated telephone appointment reminders. The prespecified endpoints were receipt of either pre- or postpartum influenza vaccination calculated cumulatively at the end of each month (September-December 2011). Results. After adjusting for gestational age and number of clinic visits, women who received the intervention were 30% more likely to be vaccinated as of December 2011 (adjusted odds ratio [AOR] = 1.30; 95% confidence interval [CI] = 1.003, 1.69 end of September: AOR = 1.34; 95% CI = 0.98, 1.85; October: AOR = 1.35; 95% CI = 1.05, 1.75; November: AOR = 1.27; 95% CI = 0.98, 1.65). The subgroup of women early in the third trimester at randomization showed the greatest intervention effect (December 31: 61.9% intervention vs 49.0% control; AOR = 1.88; 95% CI = 1.12, 3.15). Conclusions. In this low-income obstetric population, text messaging was associated with increased influenza vaccination, especially in those who received messages early in their third trimester. (Am J Public Health. Published online ahead of print December 19, 2013: e1-e6. doi:10.2105/AJPH.2013.301620).
    American Journal of Public Health 12/2013; DOI:10.2105/AJPH.2013.301620 · 4.23 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Seasonal influenza vaccination offers one of the best population-level protections against influenza-like illness (ILI). For most people, a single dose prior to the flu season offers adequate immunogenicity. HIV+ patients, however, tend to exhibit a shorter period of clinical protection, and therefore may not retain immunogenicity for the entire season. Building on the work of Nosyk et al. (2011) that determined a single dose is the optimal dosing strategy for HIV+ patients, we investigate the optimal time to administer this vaccination. Using data from the "single dose" treatment arm of an RCT conducted at 12 CIHR Canadian HIV Trials Network sites we estimated semimonthly clinical seroprotection levels for a cohort (N=93) based on HAI titer levels. These estimates were combined with CDC attack rate data for the three main strains of seasonal influenza to estimate instances of ILI over different vaccination timing strategies. Using bootstrap resampling of the cohort, nine years of CDC data, and parameter distributions, we developed a Markov cohort model that included probabilistic sensitivity analysis. Cost, quality adjusted life-years (QALYs), and net monetary benefits are presented for each timing strategy. The beginning of December is the optimal time for HIV+ patients to receive the seasonal influenza vaccine. Assuming a willingness-to-pay threshold of $50,000, the net monetary benefit associated with a Dec 1 vaccination date is $19,501.49 and the annual QALY was 0.833744. Our results support a policy of administering the seasonal influenza vaccination for this population in the middle of November or beginning of December, assuming nothing is know about the upcoming flu season. But because the difference in between this strategy and the CDC guideline is small-12 deaths averted per year and a savings of $60 million across the HIV+ population in the US-more research is needed concerning strategies for subpopulations.
    Vaccine 12/2013; 32(6). DOI:10.1016/j.vaccine.2013.11.103 · 3.49 Impact Factor