tetano
Editor, Senior Moderator
Vaccine
. 2022 May 4;S0264-410X(22)00358-9.
doi: 10.1016/j.vaccine.2022.03.047. Online ahead of print.
Impact of prior infection and repeated vaccination on post-vaccination antibody titers of the influenza A(H1N1)pdm09 strain in Taiwan schoolchildren: Implications for public health
Wei Liu[SUP] 1 [/SUP], Yu-Hui Lien[SUP] 1 [/SUP], Ping-Ing Lee[SUP] 2 [/SUP], Ta-Chien Chan[SUP] 3 [/SUP], Lih-Chiann Wang[SUP] 4 [/SUP], Chin-Rur Yang[SUP] 5 [/SUP], Mei-Shang Ho[SUP] 6 [/SUP], Juine-Ruey Chen[SUP] 7 [/SUP], Chia-Chi Ku[SUP] 8 [/SUP], Chwan-Chuen King[SUP] 9 [/SUP]
Affiliations
Abstract
Background: The objective of this study was to evaluate the effects of prior-infection and repeated vaccination on post-vaccination antibody titers.
Methods: A(H1N1)pdm09 strain was included in 2009 pandemic monovalent, 2010-2011, and 2011-2012 trivalent influenza vaccines (MIVpdm09, TIV10/11, TIV11/12) in Taiwan. During the 2011-2012 influenza season, we conducted a prospective sero-epidemiological cohort study among schoolchildren from grades 1 - 6 in the two elementary schools in Taipei with documented A(H1N1)pdm09 vaccination records since 2009. Serum samples were collected at pre-vaccination, 1-month, and 4-months post-vaccination (T1, T2, T3). Anti-A(H1N1)pdm09 hemagglutination inhibition titers (HI-Ab-titers) were examined. We also investigated the impact of four vaccination histories [(1) no previous vaccination (None), (2) vaccinated in 2009-2010 season (09v), (3) vaccinated in 2010-2011 season (10v), and (4) vaccinated consecutively in 2009-2010 and 2010-2011 seasons (09v + 10v)] and pre-vaccination HI-Ab levels on post-vaccination HI-Ab responses as well as adjusted vaccine effectiveness (aVE) against serologically-defined infection from T2 to T3.
Results: TIV11/12 had zero serious adverse events reported. A(H1N1)pdm09 strain in TIV11/12 elicited seroprotective Ab-titers in 98% of children and showed promising protection (aVE: 70.3% [95% confidence interval (CI): 51.0-82.1%]). Previously unvaccinated but infected children had a 3.96 times higher T2 geometric mean titer (T2-GMT) of HI-Ab than those naïve to A(H1N1)pdm09 (GMT [95% CI]: 1039.7[585.3-1845.9] vs. 262.5[65.9-1045], p = 0.046). Previously vaccinated children with seroprotective T1-Ab-titers had a higher T2-GMT and a greater aVE than those with non-seroprotective T1-Ab-titers. Repeatedly vaccinated children had lower T2-GMT than those receiving primary doses of TIV11/12. However, after controlling prior infection and T1-Ab-titers, differences in T2-GMT among the four vaccination histories became insignificant (p = 0.16).
Conclusion: This study supports the implementation of annual mass-vaccination with A(H1N1)pdm09 in schoolchildren for three consecutive influenza seasons when vaccine and circulating strains were well matched, and found that prior infection and pre-vaccination HI-Ab levels positively impacted post-vaccination HI-Ab responses.
Keywords: A(H1N1)pdm09 virus; Antibody response; Exposure history; Inactivated influenza vaccine; Repeated vaccination; Schoolchildren; Taiwan.
. 2022 May 4;S0264-410X(22)00358-9.
doi: 10.1016/j.vaccine.2022.03.047. Online ahead of print.
Impact of prior infection and repeated vaccination on post-vaccination antibody titers of the influenza A(H1N1)pdm09 strain in Taiwan schoolchildren: Implications for public health
Wei Liu[SUP] 1 [/SUP], Yu-Hui Lien[SUP] 1 [/SUP], Ping-Ing Lee[SUP] 2 [/SUP], Ta-Chien Chan[SUP] 3 [/SUP], Lih-Chiann Wang[SUP] 4 [/SUP], Chin-Rur Yang[SUP] 5 [/SUP], Mei-Shang Ho[SUP] 6 [/SUP], Juine-Ruey Chen[SUP] 7 [/SUP], Chia-Chi Ku[SUP] 8 [/SUP], Chwan-Chuen King[SUP] 9 [/SUP]
Affiliations
- PMID: 35525727
- DOI: 10.1016/j.vaccine.2022.03.047
Abstract
Background: The objective of this study was to evaluate the effects of prior-infection and repeated vaccination on post-vaccination antibody titers.
Methods: A(H1N1)pdm09 strain was included in 2009 pandemic monovalent, 2010-2011, and 2011-2012 trivalent influenza vaccines (MIVpdm09, TIV10/11, TIV11/12) in Taiwan. During the 2011-2012 influenza season, we conducted a prospective sero-epidemiological cohort study among schoolchildren from grades 1 - 6 in the two elementary schools in Taipei with documented A(H1N1)pdm09 vaccination records since 2009. Serum samples were collected at pre-vaccination, 1-month, and 4-months post-vaccination (T1, T2, T3). Anti-A(H1N1)pdm09 hemagglutination inhibition titers (HI-Ab-titers) were examined. We also investigated the impact of four vaccination histories [(1) no previous vaccination (None), (2) vaccinated in 2009-2010 season (09v), (3) vaccinated in 2010-2011 season (10v), and (4) vaccinated consecutively in 2009-2010 and 2010-2011 seasons (09v + 10v)] and pre-vaccination HI-Ab levels on post-vaccination HI-Ab responses as well as adjusted vaccine effectiveness (aVE) against serologically-defined infection from T2 to T3.
Results: TIV11/12 had zero serious adverse events reported. A(H1N1)pdm09 strain in TIV11/12 elicited seroprotective Ab-titers in 98% of children and showed promising protection (aVE: 70.3% [95% confidence interval (CI): 51.0-82.1%]). Previously unvaccinated but infected children had a 3.96 times higher T2 geometric mean titer (T2-GMT) of HI-Ab than those naïve to A(H1N1)pdm09 (GMT [95% CI]: 1039.7[585.3-1845.9] vs. 262.5[65.9-1045], p = 0.046). Previously vaccinated children with seroprotective T1-Ab-titers had a higher T2-GMT and a greater aVE than those with non-seroprotective T1-Ab-titers. Repeatedly vaccinated children had lower T2-GMT than those receiving primary doses of TIV11/12. However, after controlling prior infection and T1-Ab-titers, differences in T2-GMT among the four vaccination histories became insignificant (p = 0.16).
Conclusion: This study supports the implementation of annual mass-vaccination with A(H1N1)pdm09 in schoolchildren for three consecutive influenza seasons when vaccine and circulating strains were well matched, and found that prior infection and pre-vaccination HI-Ab levels positively impacted post-vaccination HI-Ab responses.
Keywords: A(H1N1)pdm09 virus; Antibody response; Exposure history; Inactivated influenza vaccine; Repeated vaccination; Schoolchildren; Taiwan.