Concurrent and cross-season protection of inactivated influenza vaccine against A(H1N1)pdm09 illness among young children: 2012-2013 case-control evaluation of influenza vaccine effectiveness.
In 2012-2013, we examined 1729 laboratory-confirmed A(H1N1)pdm09 influenza cases matched 1:1 with healthy controls and estimated influenza vaccine effectiveness (VE) for trivalent inactivated influenza vaccine (IIV3) to be 67% (95% confidence interval=58-74%) for ages 8 months to 6 years old. Among children aged 8-35 months old, VE for fully vaccinated children (73%, 60-81%) was significantly higher than VE for partially vaccinated children (55%, 33-70%). Significant cross-season protection from prior IIV3 was noted, including VE of 31% (8-48%) from IIV3 received in 2010-2011 against influenza illness in 2012--2013 without subsequent boosting doses.
Guangzhou Center for Disease Control and Prevention, Guangzhou, China. Electronic address: fuchuanxi@gmail.com.
Chuanxi
C
Fu
Guangzhou Center for Disease Control and Prevention, Guangzhou, China.
Jianxiong
J
Xu
Nanfang Hospital, Health Management Center, Nanfang Hospital, Southern Medical University, Guangzhou, China.
Jinyan
J
Lin
Guangzhou Center for Disease Control and Prevention, Guangzhou, China.
Ming
M
Wang
Guangzhou Center for Disease Control and Prevention, Guangzhou, China.
Kuibiao
K
Li
Nanfang Hospital, Health Management Center, Nanfang Hospital, Southern Medical University, Guangzhou, China.
Jing
J
Ge
Influenza Division, Centers for Disease Control and Prevention, Atlanta, United States. Electronic address: isq8@cdc.gov.
Mark G
MG
Thompson
D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D002681:China; D056738:Cross Protection; D005260:Female; D006801:Humans; D007223:Infant; D053118:Influenza A Virus, H1N1 Subtype / Q000276:immunology*; D007252:Influenza Vaccines / Q000276:immunology*; D007251:Influenza, Human / Q000517:prevention & control* / Q000821:virology; D008297:Male; D012621:Seasons; D014611:Vaccination; D064166:Vaccine Potency; D015164:Vaccines, Inactivated / Q000276:immunology
D007252:Influenza Vaccines; D015164:Vaccines, Inactivated
A(H1N1)pdm09 influenza; Children; Influenza vaccines; Prior vaccination; Vaccine effectiveness