tetano
Editor, Senior Moderator
Pediatr Infect Dis J. 2015 Dec 9. [Epub ahead of print]
[h=1]Influenza Vaccine Effectiveness for Fully and Partially Vaccinated Children 6 months to 8 Years Old during 2011-2012 and 2012-2013: The Importance of Two Priming Doses.[/h] Thompson MG[SUP]1[/SUP], Clippard J, Petrie JG, Jackson ML, McLean HQ, Gaglani M, Reis EC, Flannery B, Monto AS, Jackson L, Belongia EA, Murthy K, Zimmerman RK, Thaker S, Fry AM.
[h=3]Author information[/h]
[h=3]Abstract[/h] [h=4]BACKGROUND:[/h] Few studies have examined the effectiveness of full vs. partial vaccination with inactivated trivalent influenza vaccines (IIV3) as defined by the U.S. CDC Advisory Committee on Immunization Practices (ACIP).
[h=4]METHODS:[/h] Respiratory swabs were collected from outpatients aged 6 months to 8 years with acute cough for ≤7 days in clinics in 5 states during the 2011-2012 and 2012-2013 influenza seasons. Influenza was confirmed by real-time reverse transcription polymerase chain reaction assay. Receipt of current season IIV3 and up to 4 prior vaccinations was documented from medical records and immunization registries. Using a test-negative design, vaccine effectiveness (VE) was estimated adjusting for age, race/ethnicity, medical conditions, study site, and month of enrollment.
[h=4]RESULTS:[/h] We did not observe higher VE for children fully vs. partially vaccinated with IIV3, as defined by U.S. ACIP, though our sample of partially vaccinated children was relatively small. However, among children aged 2-8 years in both seasons and against A(H3N2) and B influenza illness separately, VE point estimates were consistently higher for children who had received 2 doses in the same prior season compared to those without (VE range of 58-80% vs. 33-44%, respectively). Across seasons, the odds of A(H3N2) illness despite IIV3 vaccination were 2.4-fold (95% CI = 1.4-4.3) higher among children who had not received 2 doses in the same prior season. We also noted residual protection among unvaccinated children who were vaccinated the previous season (VE range = 36-40% across outcomes).
[h=4]CONCLUSION:[/h] Vaccination with IIV3 may provide preventive benefit in subsequent seasons, including possible residual protection if vaccination is missed. Two vaccine doses in the same season may be more effective than alternative priming strategies.
PMID: 26658375 [PubMed - as supplied by publisher]
[h=1]Influenza Vaccine Effectiveness for Fully and Partially Vaccinated Children 6 months to 8 Years Old during 2011-2012 and 2012-2013: The Importance of Two Priming Doses.[/h] Thompson MG[SUP]1[/SUP], Clippard J, Petrie JG, Jackson ML, McLean HQ, Gaglani M, Reis EC, Flannery B, Monto AS, Jackson L, Belongia EA, Murthy K, Zimmerman RK, Thaker S, Fry AM.
[h=3]Author information[/h]
[h=3]Abstract[/h] [h=4]BACKGROUND:[/h] Few studies have examined the effectiveness of full vs. partial vaccination with inactivated trivalent influenza vaccines (IIV3) as defined by the U.S. CDC Advisory Committee on Immunization Practices (ACIP).
[h=4]METHODS:[/h] Respiratory swabs were collected from outpatients aged 6 months to 8 years with acute cough for ≤7 days in clinics in 5 states during the 2011-2012 and 2012-2013 influenza seasons. Influenza was confirmed by real-time reverse transcription polymerase chain reaction assay. Receipt of current season IIV3 and up to 4 prior vaccinations was documented from medical records and immunization registries. Using a test-negative design, vaccine effectiveness (VE) was estimated adjusting for age, race/ethnicity, medical conditions, study site, and month of enrollment.
[h=4]RESULTS:[/h] We did not observe higher VE for children fully vs. partially vaccinated with IIV3, as defined by U.S. ACIP, though our sample of partially vaccinated children was relatively small. However, among children aged 2-8 years in both seasons and against A(H3N2) and B influenza illness separately, VE point estimates were consistently higher for children who had received 2 doses in the same prior season compared to those without (VE range of 58-80% vs. 33-44%, respectively). Across seasons, the odds of A(H3N2) illness despite IIV3 vaccination were 2.4-fold (95% CI = 1.4-4.3) higher among children who had not received 2 doses in the same prior season. We also noted residual protection among unvaccinated children who were vaccinated the previous season (VE range = 36-40% across outcomes).
[h=4]CONCLUSION:[/h] Vaccination with IIV3 may provide preventive benefit in subsequent seasons, including possible residual protection if vaccination is missed. Two vaccine doses in the same season may be more effective than alternative priming strategies.
PMID: 26658375 [PubMed - as supplied by publisher]