School-Based Influenza Vaccination: Health and Economic Impact of Maine's 2009 Influenza Vaccination Program.

OBJECTIVE: To estimate the societal economic and health impacts of Maine's school-based influenza vaccination (SIV) program during the 2009 A(H1N1) influenza pandemic. DATA SOURCES: Primary and secondary data covering the 2008-09 and 2009-10 influenza seasons. STUDY DESIGN: We estimated weekly monovalent influenza vaccine uptake in Maine and 15 other states, using difference-in-difference-in-differences analysis to assess the program's impact on immunization among six age groups. We also developed a health and economic Markov microsimulation model and conducted Monte Carlo sensitivity analysis. DATA COLLECTION: We used national survey data to estimate the impact of the SIV program on vaccine coverage. We used primary data and published studies to develop the microsimulation model. PRINCIPAL FINDINGS: The program was associated with higher immunization among children and lower immunization among adults aged 18-49 years and 65 and older. The program prevented 4,600 influenza infections and generated $4.9 million in net economic benefits. Cost savings from lower adult vaccination accounted for 54 percent of the economic gain. Economic benefits were positive in 98 percent of Monte Carlo simulations. CONCLUSIONS: SIV may be a cost-beneficial approach to increase immunization during pandemics, but programs should be designed to prevent lower immunization among nontargeted groups.

Factors associated with uptake of the Influenza A(H1N1)pdm09 monovalent pandemic vaccine in K-12 Public Schools, Maine 2009-2010.

CONTEXT AND OBJECTIVE: Maine implemented a statewide pre-K through 12-school vaccination program during the 2009-2010 H1N1 influenza pandemic. The main objective of this study was to determine which school, nurse, consent form, and clinic factors were associated with school-level vaccination rates for the first dose of the 2009 H1N1 pandemic vaccine. METHODS: In April 2010, school nurses or contacts were e-mailed electronic surveys. Generalized linear mixed regression was used to predict adjusted vaccination rates using random effects to account for correlations within school districts. Elementary and secondary (middle and high) schools were analyzed separately. RESULTS: Of 645 schools invited to participate, 82% (n = 531) completed the survey. After excluding schools that were ineligible or could not provide outcome data, data for 256 elementary and 124 secondary public schools were analyzed and included in the multivariable analyses. The overall, unadjusted, vaccination rate was 51% for elementary schools and 45% for secondary schools. Elementary schools that had 50 or fewer students per grade, had availability of additional nursing staff, which did not require parental presence at the H1N1 clinic or disseminated consent forms by mail and backpack (compared with backpack only) had statistically significant (P < .05) higher (adjusted) vaccination rates. For secondary schools, the vaccination rate for schools with the lowest proportion of students receiving subsidized lunch (ie, highest socioeconomic status) was 58% compared with 37% (P < .001) for schools with the highest proportion receiving subsidized lunch. CONCLUSIONS: Several factors were independently associated with vaccination rates. For elementary schools, planners should consider strategies such as providing additional nursing staff and disseminating consent forms via multiple methods. The impact of additional factors, including communication approaches and parent and student attitudes, needs to be investigated, especially for secondary schools.

Effectiveness of 1 dose of influenza A (H1N1) 2009 monovalent vaccines in preventing reverse-transcription polymerase chain reaction-confirmed H1N1 infection among school-aged children in maine.

BACKGROUND: In late October 2009, school-located pandemic vaccination was initiated in Maine before or concurrent with 2009 pandemic influenza A (H1N1) virus (pH1N1) peak activity. METHODS: A case-control evaluation of 2009 H1N1 vaccine effectiveness was conducted in schools in Cumberland County, Maine. A case was a child who had an acute respiratory illness during 2 November-18 December 2009, and who tested positive for pH1N1 by real-time reverse-transcription polymerase chain reaction (rRT-PCR). For each case, ≥ 4 event time-matched controls were sampled among classmates present in school during the study period who did not have an influenza-like illness. Vaccine effectiveness was calculated as (1 - adjusted odds ratio [aOR])100%; aOR was estimated by using weighted logistic regression. RESULTS: After adjusting for a diagnosis of asthma, 1 dose of 2009 H1N1 vaccine provided 69% protection (95% confidence interval (CI), 13-89) against rRT-PCR-confirmed H1N1 infection. Vaccine effectiveness estimates for live attenuated and inactivated vaccine were 81% (95% CI, -37 to 97), and 58% (95% CI: -39 to 87), respectively. CONCLUSIONS: One dose of monovalent pandemic vaccine provided substantial protection against pH1N1 infection among school-aged children.

Costs of school-located influenza vaccination clinics in Maine during the 2009-2010 H1N1 pandemic.

This study retrospectively estimated costs for a convenience sample of school-located vaccination (SLV) clinics conducted in Maine during the 2009-2010 influenza season. Surveys were developed to capture the cost of labor including unpaid volunteers as well as supplies and materials used in SLV clinics. Six nurses from different school districts completed a clinic day survey on staff time; four of the six also provided data for materials and supplies. For all clinics, average per-dose labor cost was estimated at $5.95. Average per-dose material cost, excluding vaccine, was $5.76. From the four complete clinic survey responses, total per-dose cost was estimated to be an average of $13.51 (range = $4.91-$32.39). Use of donated materials and uncompensated volunteer staff could substantially reduce per-dose cost. Average per-dose cost could also be lowered by increasing the number of doses administered in a clinic.

Coordination costs for school-located influenza vaccination clinics, Maine, 2009 H1N1 pandemic.

School nurses played a key role in Maine's school-located influenza vaccination (SLV) clinics during the 2009-2010 pandemic season. The objective of this study was to determine, from the school district perspective, the labor hours and costs associated with outside-clinic coordination activities (OCA). The authors defined OCA as labor hours spent by staff outside of clinic operations. The authors surveyed a convenience sample of 10 school nurses from nine school districts. Eight nurses responded to the survey, representing seven districts, 45 schools and 84 SLV clinics that provided a total of 22,596 vaccine doses (H1N1 and seasonal combined) to children and adolescents. The mean total OCA time per clinic was 69 hours: out of total hours, 22 (36%) were spent outside regular clinic operation time. The authors estimated the mean cost of OCA to be $15.36 per dose. Survey respondents reported that costs would be lower during non-pandemic seasons and as schools become more proficient at planning clinics.

Effects of immunizing school children with 2009 influenza A (H1N1) monovalent vaccine on absenteeism among students and teachers in Maine.

The overall and indirect effects of immunizing school children with influenza A (H1N1) 2009 pandemic virus vaccine prior to and during the peak of virus circulation were evaluated on student and teacher school absenteeism. We used records collected from late 2009 through early 2010 from schools in four Maine counties. Mixed logistic regression models were used to estimate the daily association between school-level immunization coverage and absenteeism by level of influenza activity, after adjusting for the proportion of students receiving reduced-cost lunches, student minority status, absences adjacent to weekends and Thanksgiving, rural school location, and the circulation of other respiratory viruses. Increasing student immunization coverage was associated with reduced absenteeism during periods of high influenza activity. For example, as immunization coverage during the peak week of pandemic virus circulation increased from 38% to 69% (the 10th and 90th percentiles of observed coverage, respectively), relative reductions in daily absenteeism among all students, unimmunized students, and teachers were 8.2% (95% confidence interval [CI]: 6.5, 9.9), 5.7% (95% CI: 4.2, 7.3), and 8.7% (95% CI: 1.3, 16), respectively. Increased vaccination coverage among school-aged Maine children had modest overall and indirect effects on student and teacher absenteeism, despite vaccination occurring just prior and during peak pandemic virus circulation.