tetano
Editor, Senior Moderator
Clin Infect Dis. 2016 Oct 4. pii: ciw635. [Epub ahead of print]
[h=1]2014-2015 Influenza Vaccine Effectiveness in the United States by Vaccine Type.[/h] Zimmerman RK, Nowalk MP, Chung J, Jackson ML, Jackson LA, Petrie JG, Monto AS, McLean HQ, Belongia EA, Gaglani M, Murthy K, Fry AM, Flannery B; U.S. Flu VE Investigators.
[h=3]Collaborators (103)[/h]
[h=3]Abstract[/h] [h=4]BACKGROUND:[/h] The circulating A/H3N2 influenza viruses drifted significantly after the selection of strains for the 2014-2015 influenza vaccines. Also in 2014-2015, the Advisory Committee on Immunization Practices recommended preferential use of live attenuated influenza vaccine (LAIV) over inactivated influenza vaccine (IIV) among children 2-8 years old.
[h=4]METHODS:[/h] Vaccine effectiveness (VE) across age groups and vaccine types was examined among individuals seeking outpatient treatment for acute respiratory illness from 5 U.S. sites using a test-negative design that compared the odds of vaccination among reverse transcription polymerase chain reaction-confirmed influenza positives and negatives.
[h=4]RESULTS:[/h] Of the 9,311 enrollees with complete data, 7,078 (76%) were negative for influenza, 1,840 (19.8%) were positive for influenza A (A/H3N2, n=1817) and 395 (4.2%) for influenza B (B/Yamagata, n=340). The overall adjusted VE for influenza A and B was 19% (95%CI= 10% to 27%) and was statistically significant in all age strata except 18-64 year-olds. The adjusted VE of 6% (95%CI= -5% to 17%) against A/H3N2-associated illness was not statistically significant, unlike VE for influenza B/Yamagata which was 55% (95%CI= 43% to 65%). Among those aged 2-8 years, VE against A/H3N2 was 15% (95%CI= -16% to 38%) for IIV and -3% (CI= -50% to 29%) for LAIV; whereas, VE against B/Yamagata was 40% (95%CI= -20% to 70%) for IIV and 74% (95%CI= 25% to 91%) for LAIV.
[h=4]CONCLUSION:[/h] The 2014-2015 influenza vaccines offered little protection against the predominant influenza A/H3N2 virus, but were effective against influenza B. Preferential use of LAIV among young children was not supported.
Published by Oxford University Press for the Infectious Diseases Society of America 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.
PMID: 27702768 DOI: 10.1093/cid/ciw635
[PubMed - as supplied by publisher]
[h=1]2014-2015 Influenza Vaccine Effectiveness in the United States by Vaccine Type.[/h] Zimmerman RK, Nowalk MP, Chung J, Jackson ML, Jackson LA, Petrie JG, Monto AS, McLean HQ, Belongia EA, Gaglani M, Murthy K, Fry AM, Flannery B; U.S. Flu VE Investigators.
[h=3]Collaborators (103)[/h]
[h=3]Abstract[/h] [h=4]BACKGROUND:[/h] The circulating A/H3N2 influenza viruses drifted significantly after the selection of strains for the 2014-2015 influenza vaccines. Also in 2014-2015, the Advisory Committee on Immunization Practices recommended preferential use of live attenuated influenza vaccine (LAIV) over inactivated influenza vaccine (IIV) among children 2-8 years old.
[h=4]METHODS:[/h] Vaccine effectiveness (VE) across age groups and vaccine types was examined among individuals seeking outpatient treatment for acute respiratory illness from 5 U.S. sites using a test-negative design that compared the odds of vaccination among reverse transcription polymerase chain reaction-confirmed influenza positives and negatives.
[h=4]RESULTS:[/h] Of the 9,311 enrollees with complete data, 7,078 (76%) were negative for influenza, 1,840 (19.8%) were positive for influenza A (A/H3N2, n=1817) and 395 (4.2%) for influenza B (B/Yamagata, n=340). The overall adjusted VE for influenza A and B was 19% (95%CI= 10% to 27%) and was statistically significant in all age strata except 18-64 year-olds. The adjusted VE of 6% (95%CI= -5% to 17%) against A/H3N2-associated illness was not statistically significant, unlike VE for influenza B/Yamagata which was 55% (95%CI= 43% to 65%). Among those aged 2-8 years, VE against A/H3N2 was 15% (95%CI= -16% to 38%) for IIV and -3% (CI= -50% to 29%) for LAIV; whereas, VE against B/Yamagata was 40% (95%CI= -20% to 70%) for IIV and 74% (95%CI= 25% to 91%) for LAIV.
[h=4]CONCLUSION:[/h] The 2014-2015 influenza vaccines offered little protection against the predominant influenza A/H3N2 virus, but were effective against influenza B. Preferential use of LAIV among young children was not supported.
Published by Oxford University Press for the Infectious Diseases Society of America 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.
PMID: 27702768 DOI: 10.1093/cid/ciw635
[PubMed - as supplied by publisher]