Effectiveness of Non-Adjuvanted Pandemic Influenza A Vaccines for Preventing Pandemic Influenza Acute Respiratory Illness Visits in 4 U.S. Communities
Published Date:Aug 12 2011
Source:PLoS One. 2011; 6(8).
Corporate Authors:for the U.S. Flu-VE Network
Influenza A Virus, H1N1 Subtype
Reverse Transcriptase Polymerase Chain Reaction
Pubmed Central ID:PMC3155536
Funding:1K23AI074863-01/AI/NIAID NIH HHS/United States
U01 IP000170/IP/NCIRD CDC HHS/United States
U01 IP000172/IP/NCIRD CDC HHS/United States
U01 IP000183/IP/NCIRD CDC HHS/United States
U01 IP000184/IP/NCIRD CDC HHS/United States
Description:We estimated the effectiveness of four monovalent pandemic influenza A (H1N1) vaccines (three unadjuvanted inactivated, one live attenuated) available in the U.S. during the pandemic. Patients with acute respiratory illness presenting to inpatient and outpatient facilities affiliated with four collaborating institutions were prospectively recruited, consented, and tested for influenza. Analyses were restricted to October 2009 through April 2010, when pandemic vaccine was available. Patients testing positive for pandemic influenza by real-time RT-PCR were cases; those testing negative were controls. Vaccine effectiveness was estimated in logistic regression models adjusted for study community, patient age, timing of illness, insurance status, enrollment site, and presence of high-risk medical conditions. Pandemic virus was detected in 1,011 (15%) of 6,757 enrolled patients. Fifteen (1%) of 1,011 influenza positive cases and 1,042 (18%) of 5,746 test-negative controls had record-verified pandemic vaccination >14 days prior to illness onset. Adjusted effectiveness (95% confidence interval) for pandemic vaccines combined was 56% (23%, 75%). Adjusted effectiveness for inactivated vaccines alone (79% of total) was 62% (25%, 81%) overall and 32% (-92%, 76%), 89% (15%, 99%), and -6% (-231%, 66%) in those aged 0.5 to 9, 10 to 49, and 50+ years, respectively. Effectiveness for the live attenuated vaccine in those aged 2 to 49 years was only demonstrated if vaccination >7 rather than >14 days prior to illness onset was considered (61%∶ 12%, 82%). Inactivated non-adjuvanted pandemic vaccines offered significant protection against confirmed pandemic influenza-associated medical care visits in young adults.
text/plain image/gif image/jpeg text/plain application/msword image/gif image/jpeg image/gif image/jpeg image/gif image/jpeg image/gif image/jpeg
You May Also Like: