Reducing Absenteeism In a County School System Through School-Based Influenza Vaccination Clinics

Background: During the 2009 H1N1 pandemic, the Kanawha-Charleston Health Department partnered with the county school system and used grant funding from the CDC to implement school-located vaccination (SLV) clinics as a delivery system for the H1N1 vaccination to ensure children were vaccinated.  KCHD vaccinated nearly 15,000 children, nearly 50% of all Kanawha County students.   In 2010, KCHD decided to continue the SLVs, offering seasonal influenza immunization to every primary and secondary student in the county free of charge.  Parents were requested to provide insurance information if available which allowed KCHD to bill insurers and recoup all costs of the SLVs.  

Objectives: With a sustainable influenza immunization program in place, KCHD’s next step was to demonstrate that the program was effective in decreasing illness.

Methods: Detailed information was collected from each SLV in 2009 and 2010 and aggregated to determine uptake rates by school and grade level.  Absence data was aggregated by individual school, school level, CDC ILI week, and year.  These data were then analyzed together to determine if immunization rates had any measurable effect on absence.

Results: Results of this analysis vary widely depending on school and grade level.  Elementary schools, with the highest uptake rates and the steadiest absence rates, demonstrated a significant (a=.05) reduction in expected absence during peak influenza season.  Baseline data suggested an average increase of absenteeism during peak influenza season of 14.2 percent in elementary schools.  During the two intervention years, the absence rate increased only 5.8 percent at this time, a reduction in expected absenteeism of nearly 60 percent. 

Conclusions: While continued data collection and analysis is warranted, the results of this study suggest that SLVs can decrease influenza illness in schools.  Importantly, the Kanawha-Charleston Health Department has successfully demonstrated that it is possible to create a self-sustaining, school-based influenza immunization program without external funding.