Despite increase, full influenza vaccination coverage remained below 50%
From 2000 to 2001 through 2010 to 2011, influenza vaccination increased among children living in Tennessee, but the proportion of fully vaccinated children remained less than 50%, according to study findings.
Astride Jules, MD, MPH, a clinical instructor at Vanderbilt University School of Medicine, and colleagues assessed influenza-related hospitalization, ED visits and vaccination rates for children hospitalized with acute respiratory illness or fever in Davidson County, Tenn. Study participants were aged 6 to 59 months.
ED visits for acute respiratory illness or fever ranged from 106 to 206 during the study period, which included 10 influenza seasons. Hospitalizations for acute respiratory illness or fever ranged from 3,100 to 5,619.
Influenza was detected in 5% to 50% of hospitalizations and in 10% to 48% of ED visits for either condition. Annually, the number of influenza-related hospitalizations ranged from 1.9 per 10,000 children to 16 per 10,000 children.
During nonpandemic seasons, there was a median of 4.5 hospitalizations per 10,000 children (95% CI, 1.9-11.1) vs. a median of 5.2 hospitalizations per 10,000 children (95% CI, 2.3-12.6) during the pandemic season of 2009 to 2010.
Researchers determined a median of 143 ED visits per 10,000 children during nonpandemic seasons (95% CI, 58-320), compared with a median of 290 ED visits per 10,000 children (95% CI, 137-540) during 2009 to 2010.
Influenza-related hospitalizations decreased over time, according to analyses that included and excluded the pandemic year (P<.05). Conversely, analyses that included and excluded the pandemic year indicated that influenza-related ED visits increased (P<.05).
From 2000 to 2004, before influenza was routinely recommended for all children, the proportion of fully vaccinated children remained below 6%. Vaccine uptake increased progressively, however, peaking in 2010 to 2011 when 38% of children were fully vaccinated, the researchers wrote.
“Influenza vaccination of children increased over time, particularly since 2004 to 2005 when influenza vaccination was recommended for children aged 6 to 23 months; however, vaccination remained below 50%,” Jules and colleagues wrote. “Influenza still causes substantial burden in young children. Optimal vaccine uptake has the potential for reducing disease burden in young children.”
Disclosure: The researchers report financial ties with AstraZeneca, MedImmune, Merck, Novartis, Quidel, Sanofi Pasteur and Teva. The study was supported by the CDC.