tetano
Editor, Senior Moderator
Clin Infect Dis. 2019 Dec 20. pii: ciz1203. doi: 10.1093/cid/ciz1203. [Epub ahead of print] [h=1]Heterologous Antibody Responses Conferred by A(H3N2) Variant and Seasonal Influenza Vaccination against Newly Emerged 2016-2018 A(H3N2) Variant Viruses in Healthy Persons.[/h]
Liu F[SUP]1[/SUP], Levine MZ[SUP]1[/SUP].
[h=3]Author information[/h] 1 Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA.
[h=3]Abstract[/h] [h=4]BACKGROUND:[/h] Swine origin A(H3N2) variant (A(H3N2)v) viruses continue to evolve and remain a public health threat. Recent outbreaks in humans in 2016-2018 were caused by a newly emerged A(H3N2)v cluster 2010.1 which are genetically and antigenically distinct from the previously predominant cluster IV. To address the public health risk, we evaluated the levels of heterologous cross-reactive antibodies to A(H3N2)v cluster 2010.1 viruses induced from an existing cluster IV A(H3N2)v vaccine and several seasonal inactivated influenza vaccines (IIVs) in adults, elderly and children.
[h=4]METHODS:[/h] Human vaccine sera and ferret antisera were analyzed by hemagglutination inhibition (HI) and neutralization assays against representative A(H3N2)v viruses from clusters IV and 2010.1, and seasonal A(H3N2) viruses.
[h=4]RESULTS:[/h] Ferret antisera detected no or little cross-reactivity between the two A(H3N2)v clusters, or between A(H3N2)v and seasonal A(H3N2) viruses. In humans, cluster IV A(H3N2)v vaccine induced antibodies cross-reactive to cluster 2010.1 viruses in about 1/3 of the 89 adult and elderly vaccinees. Seasonal IIVs did not induce seroprotective antibodies (≥ 40) to A(H3N2)v viruses in young children, but induced higher antibodies to A(H3N2)v viruses in cluster 2010.1 than those in cluster IV in adults.
[h=4]CONCLUSIONS:[/h] Cluster IV A(H3N2)v vaccine did not provide sufficient heterologous antibody responses against the new 2010.1 cluster A(H3N2)v viruses. Seasonal IIV could not induce seroprotective antibodies to 2010.1 cluster A(H3N2)v viruses in young children, suggesting that young children are still at high risk to the newly emerged A(H3N2)v viruses. Continued surveillance on A(H3N2)v viruses is critical for risk assessment and pandemic preparedness.
Published by Oxford University Press for the Infectious Diseases Society of America 2019. This work is written by (a) US Government employee(s) and is in the public domain in the US.
[h=4]KEYWORDS:[/h] A(H3N2) variant viruses (A(H3N2)v); HI and MN antibody responses; antigenic analysis; heterologous responses; influenza vaccine; seasonal Influenza A(H3N2) viruses
PMID: 31858129 DOI: 10.1093/cid/ciz1203
Liu F[SUP]1[/SUP], Levine MZ[SUP]1[/SUP].
[h=3]Author information[/h] 1 Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA.
[h=3]Abstract[/h] [h=4]BACKGROUND:[/h] Swine origin A(H3N2) variant (A(H3N2)v) viruses continue to evolve and remain a public health threat. Recent outbreaks in humans in 2016-2018 were caused by a newly emerged A(H3N2)v cluster 2010.1 which are genetically and antigenically distinct from the previously predominant cluster IV. To address the public health risk, we evaluated the levels of heterologous cross-reactive antibodies to A(H3N2)v cluster 2010.1 viruses induced from an existing cluster IV A(H3N2)v vaccine and several seasonal inactivated influenza vaccines (IIVs) in adults, elderly and children.
[h=4]METHODS:[/h] Human vaccine sera and ferret antisera were analyzed by hemagglutination inhibition (HI) and neutralization assays against representative A(H3N2)v viruses from clusters IV and 2010.1, and seasonal A(H3N2) viruses.
[h=4]RESULTS:[/h] Ferret antisera detected no or little cross-reactivity between the two A(H3N2)v clusters, or between A(H3N2)v and seasonal A(H3N2) viruses. In humans, cluster IV A(H3N2)v vaccine induced antibodies cross-reactive to cluster 2010.1 viruses in about 1/3 of the 89 adult and elderly vaccinees. Seasonal IIVs did not induce seroprotective antibodies (≥ 40) to A(H3N2)v viruses in young children, but induced higher antibodies to A(H3N2)v viruses in cluster 2010.1 than those in cluster IV in adults.
[h=4]CONCLUSIONS:[/h] Cluster IV A(H3N2)v vaccine did not provide sufficient heterologous antibody responses against the new 2010.1 cluster A(H3N2)v viruses. Seasonal IIV could not induce seroprotective antibodies to 2010.1 cluster A(H3N2)v viruses in young children, suggesting that young children are still at high risk to the newly emerged A(H3N2)v viruses. Continued surveillance on A(H3N2)v viruses is critical for risk assessment and pandemic preparedness.
Published by Oxford University Press for the Infectious Diseases Society of America 2019. This work is written by (a) US Government employee(s) and is in the public domain in the US.
[h=4]KEYWORDS:[/h] A(H3N2) variant viruses (A(H3N2)v); HI and MN antibody responses; antigenic analysis; heterologous responses; influenza vaccine; seasonal Influenza A(H3N2) viruses
PMID: 31858129 DOI: 10.1093/cid/ciz1203