tetano
Editor, Senior Moderator
Clin Infect Dis. 2019 Dec 16. pii: ciz1198. doi: 10.1093/cid/ciz1198. [Epub ahead of print] [h=1]Neutralizing and neuraminidase antibodies correlate with protection against influenza during a late season A/H3N2 outbreak among unvaccinated military recruits.[/h]
Weiss CD[SUP]1[/SUP], Wang W[SUP]1[/SUP], Lu Y[SUP]2[/SUP], Billings M[SUP]2[/SUP], Eick-Cost A[SUP]3[/SUP], Couzens L[SUP]1[/SUP], Sanchez JL[SUP]3[/SUP], Hawksworth AW[SUP]4[/SUP], Seguin P[SUP]5[/SUP], Myers CA[SUP]3[/SUP], Forshee R[SUP]2[/SUP], Eichelberger MC[SUP]1[/SUP], Cooper MJ[SUP]3[/SUP].
[h=3]Author information[/h] 1 Division of Viral Products, Office of Vaccines Research and Review. 2 Office of Biostatistics and Epidemiology, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD. 3 Armed Forces Health Surveillance Branch, Defense Health Agency, Department of Defense, Silver Spring, MD. 4 Operational Infectious Diseases, Naval Health Research Center, San Diego, CA. 5 III Marine Expeditionary Force, Okinawa, Japan.
[h=3]Abstract[/h] [h=4]BACKGROUND:[/h] Antibodies that inhibit hemagglutination have long been considered a correlate of protection against influenza, but these antibodies are only a subset of potentially protective antibodies. Neutralizing and neuraminidase antibodies may also contribute to protection, but data on their associations with protection are limited.
[h=4]METHODS:[/h] We measured pre-outbreak hemagglutinin pseudovirus neutralization (PVN) and neuraminidase inhibition (NAI) antibody titers in unvaccinated military recruits who experienced an H3N2 influenza outbreak during training. We conducted a case-control study to investigate the association between titers and protection against influenza illness or H3N2-associated pneumonia using logistic regression.
[h=4]RESULTS:[/h] With every two-fold increase in PVN titer, the odds of medically-attended PCR-confirmed H3N2 infection (H3N2+) decreased by 41% (odds ratio (OR) 0.59, 95% CI:0.45-0.77, P<0.001) and among those who were H3N2+, the odds for pneumonia decreased by 52% (OR 0.48, CI:0.25-0.91, P=0.0249). With every two-fold increase in NAI titer, the odds of medically-attended H3N2 infection decreased by 32% (OR 0.68, 95% CI:0.53-0.87, P=0.0028), but there was no association between NAI titers and H3N2-associated pneumonia. There was also no synergistic effect of PVN and NAI antibodies.
[h=4]CONCLUSIONS:[/h] PVN and NAI titers were independently associated with reduced risk of influenza illness. NAI titers associated with protection had greater breadth of reactivity to drifted strains than PVN titers. These findings show that PVN and NAI titers are valuable biomarkers for assessing the odds of influenza infection.
? The Author(s) 2019. Published by Oxford University Press for the Infectious Diseases Society of America.
[h=4]KEYWORDS:[/h] H3N2 subtype; correlates of protection; influenza hemagglutinin; influenza neutralizing antibodies; neuraminidase inhibition antibodies
PMID: 31840159 DOI: 10.1093/cid/ciz1198
Weiss CD[SUP]1[/SUP], Wang W[SUP]1[/SUP], Lu Y[SUP]2[/SUP], Billings M[SUP]2[/SUP], Eick-Cost A[SUP]3[/SUP], Couzens L[SUP]1[/SUP], Sanchez JL[SUP]3[/SUP], Hawksworth AW[SUP]4[/SUP], Seguin P[SUP]5[/SUP], Myers CA[SUP]3[/SUP], Forshee R[SUP]2[/SUP], Eichelberger MC[SUP]1[/SUP], Cooper MJ[SUP]3[/SUP].
[h=3]Author information[/h] 1 Division of Viral Products, Office of Vaccines Research and Review. 2 Office of Biostatistics and Epidemiology, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD. 3 Armed Forces Health Surveillance Branch, Defense Health Agency, Department of Defense, Silver Spring, MD. 4 Operational Infectious Diseases, Naval Health Research Center, San Diego, CA. 5 III Marine Expeditionary Force, Okinawa, Japan.
[h=3]Abstract[/h] [h=4]BACKGROUND:[/h] Antibodies that inhibit hemagglutination have long been considered a correlate of protection against influenza, but these antibodies are only a subset of potentially protective antibodies. Neutralizing and neuraminidase antibodies may also contribute to protection, but data on their associations with protection are limited.
[h=4]METHODS:[/h] We measured pre-outbreak hemagglutinin pseudovirus neutralization (PVN) and neuraminidase inhibition (NAI) antibody titers in unvaccinated military recruits who experienced an H3N2 influenza outbreak during training. We conducted a case-control study to investigate the association between titers and protection against influenza illness or H3N2-associated pneumonia using logistic regression.
[h=4]RESULTS:[/h] With every two-fold increase in PVN titer, the odds of medically-attended PCR-confirmed H3N2 infection (H3N2+) decreased by 41% (odds ratio (OR) 0.59, 95% CI:0.45-0.77, P<0.001) and among those who were H3N2+, the odds for pneumonia decreased by 52% (OR 0.48, CI:0.25-0.91, P=0.0249). With every two-fold increase in NAI titer, the odds of medically-attended H3N2 infection decreased by 32% (OR 0.68, 95% CI:0.53-0.87, P=0.0028), but there was no association between NAI titers and H3N2-associated pneumonia. There was also no synergistic effect of PVN and NAI antibodies.
[h=4]CONCLUSIONS:[/h] PVN and NAI titers were independently associated with reduced risk of influenza illness. NAI titers associated with protection had greater breadth of reactivity to drifted strains than PVN titers. These findings show that PVN and NAI titers are valuable biomarkers for assessing the odds of influenza infection.
? The Author(s) 2019. Published by Oxford University Press for the Infectious Diseases Society of America.
[h=4]KEYWORDS:[/h] H3N2 subtype; correlates of protection; influenza hemagglutinin; influenza neutralizing antibodies; neuraminidase inhibition antibodies
PMID: 31840159 DOI: 10.1093/cid/ciz1198