What Else Did We Learn From H1N1 Flu Vaccine? – Comparison of People's Intentions with the Results of Receiving H1N1 Flu Vaccines, Random Digit Dialing (RDD) Telephone Survey 2009-2010, San Diego County

Background: The 2009 influenza A (H1N1) pandemic brought high interest in influenza vaccines from the public.  To estimate the demand of H1N1 and seasonal influenza vaccines, a Countywide survey was initiated before the H1N1 vaccines were distributed.   The post-season survey was conducted to measure the coverage rates of H1N1 and seasonal influenza vaccines.

Objectives:  Compare the needs prior to the availability of H1N1 vaccines with the coverage rates of influenza vaccines.  Measure the knowledge and attitudes regarding to flu vaccines.

Methods:  Two cross-sectional RDD telephone surveys were conducted to the County residents who were aged 18 years and older.   The pre-distribution and the post-season surveys were administered in August, 2009 and March, 2010, respectively.  In addition, respondents who had a child under age 18 years at the time of survey were asked to answer questions of influenza vaccines for his/her child. 

Results:  Total of 618 and 1,014 households participated in the pre-distribution and post-season surveys, respectively.  Thirty-six percent of adults actually received H1N1 vaccines compared to 66.1% of respondents who intended to have the vaccines in the pre-distribution surveys.  A smaller difference was observed for the children (52% vs. 62%).  Overall, the coverage rates of seasonal flu vaccines were increased by 4.5% and 9.3% for adults and children, respectively.  Almost 90% of respondents knew where and when to get the H1N1 vaccines.  However, Hispanic households reported having significantly lower knowledge of the locations where the H1N1 vaccines were distributed.  The common reasons that respondents did not have the flu vaccines were “didn’t want one” or “H1N1 isn’t serious enough.”

Conclusions:  Public intention for influenza vaccine was initially high.  Many immunization clinics were set up at schools and other sites outside of providers’ offices in response to the need.  Perceptions changed as the season progressed.  However, having consumer input early in large-scale planning efforts was useful.