tetano
Editor, Senior Moderator
Clin Infect Dis. 2017 Jul 20. doi: 10.1093/cid/cix608. [Epub ahead of print]
[h=1]The Household Influenza Vaccine Effectiveness Study: Lack of Antibody Response and Protection Following Receipt of 2014-2015 Influenza Vaccine.[/h] Petrie JG[SUP]1[/SUP], Malosh RE[SUP]1[/SUP], Cheng CK[SUP]1[/SUP], Ohmit SE[SUP]1[/SUP], Martin ET[SUP]1[/SUP], Johnson E[SUP]1[/SUP], Truscon R[SUP]1[/SUP], Eichelberger MC[SUP]2[/SUP], Gubareva LV[SUP]3[/SUP], Fry AM[SUP]3[/SUP], Monto AS[SUP]1[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] [h=4]Background:[/h] Antigenically drifted A(H3N2) viruses circulated extensively during the 2014-2015 influenza season. Vaccine effectiveness (VE) was low and not significant among outpatients but in a hospitalized population was 43%. At least one study paradoxically observed increased A(H3N2) infection among those vaccinated 3 consecutive years.
[h=4]Methods:[/h] We followed a cohort of 1341 individuals from 340 households. VE against laboratory-confirmed influenza was estimated. Hemagglutination-inhibition and neuraminidase-inhibition antibody titers were determined in subjects ≥13 years.
[h=4]Results:[/h] Influenza A(H3N2) was identified in 166 (12%) individuals and B(Yamagata) in 34 (2%). VE against A(H3N2) was -3% (95% confidence interval [CI]: -55%, 32%) and similarly ineffective between age groups; increased risk of infection was not observed among those vaccinated in 2 or 3 previous years. VE against influenza B(Yamagata) was 57% (95% CI: -3%, 82%) but only significantly protective in children <9 years (87% [95% CI: 43%, 97%]). Less than 20% of older children and adults had ≥4-fold antibody titer rise against influenza A(H3N2) and B antigens following vaccination; responses were surprisingly similar for antigens included in the vaccine and those similar to circulating viruses. Antibody against A/Hong Kong/4801/14, similar to circulating 2014-2015 A(H3N2) viruses and included in the 2016-2017 vaccine, did not significantly predict protection.
[h=4]Conclusions:[/h] Absence of VE against A(H3N2) was consistent with circulation of antigenically drifted viruses; however, generally limited antibody response following vaccination is concerning even in the context of antigenic mismatch. Although 2014-2015 vaccines were not effective in preventing A(H3N2) infection, no increased susceptibility was detected among the repeatedly vaccinated.
[h=4]KEYWORDS:[/h] household cohort study; influenza; serologic susceptibility; vaccine effectiveness; vaccine response
PMID: 29020179 DOI: 10.1093/cid/cix608
[h=1]The Household Influenza Vaccine Effectiveness Study: Lack of Antibody Response and Protection Following Receipt of 2014-2015 Influenza Vaccine.[/h] Petrie JG[SUP]1[/SUP], Malosh RE[SUP]1[/SUP], Cheng CK[SUP]1[/SUP], Ohmit SE[SUP]1[/SUP], Martin ET[SUP]1[/SUP], Johnson E[SUP]1[/SUP], Truscon R[SUP]1[/SUP], Eichelberger MC[SUP]2[/SUP], Gubareva LV[SUP]3[/SUP], Fry AM[SUP]3[/SUP], Monto AS[SUP]1[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] [h=4]Background:[/h] Antigenically drifted A(H3N2) viruses circulated extensively during the 2014-2015 influenza season. Vaccine effectiveness (VE) was low and not significant among outpatients but in a hospitalized population was 43%. At least one study paradoxically observed increased A(H3N2) infection among those vaccinated 3 consecutive years.
[h=4]Methods:[/h] We followed a cohort of 1341 individuals from 340 households. VE against laboratory-confirmed influenza was estimated. Hemagglutination-inhibition and neuraminidase-inhibition antibody titers were determined in subjects ≥13 years.
[h=4]Results:[/h] Influenza A(H3N2) was identified in 166 (12%) individuals and B(Yamagata) in 34 (2%). VE against A(H3N2) was -3% (95% confidence interval [CI]: -55%, 32%) and similarly ineffective between age groups; increased risk of infection was not observed among those vaccinated in 2 or 3 previous years. VE against influenza B(Yamagata) was 57% (95% CI: -3%, 82%) but only significantly protective in children <9 years (87% [95% CI: 43%, 97%]). Less than 20% of older children and adults had ≥4-fold antibody titer rise against influenza A(H3N2) and B antigens following vaccination; responses were surprisingly similar for antigens included in the vaccine and those similar to circulating viruses. Antibody against A/Hong Kong/4801/14, similar to circulating 2014-2015 A(H3N2) viruses and included in the 2016-2017 vaccine, did not significantly predict protection.
[h=4]Conclusions:[/h] Absence of VE against A(H3N2) was consistent with circulation of antigenically drifted viruses; however, generally limited antibody response following vaccination is concerning even in the context of antigenic mismatch. Although 2014-2015 vaccines were not effective in preventing A(H3N2) infection, no increased susceptibility was detected among the repeatedly vaccinated.
[h=4]KEYWORDS:[/h] household cohort study; influenza; serologic susceptibility; vaccine effectiveness; vaccine response
PMID: 29020179 DOI: 10.1093/cid/cix608