In:
The Journal of Infectious Diseases, Oxford University Press (OUP), Vol. 228, No. 3 ( 2023-08-11), p. 287-298
Abstract:
We evaluated the associations between baseline influenza virus–specific hemagglutination inhibition (HAI) and microneutralization (MN) titers and subsequent symptomatic influenza virus infection in a controlled human infection study. Methods We inoculated unvaccinated healthy adults aged 18–49 years with an influenza A/California/04/2009/H1N1pdm-like virus (NCT04044352). We collected serial safety labs, serum for HAI and MN, and nasopharyngeal swabs for reverse-transcription polymerase chain reaction (RT-PCR) testing. Analyses used the putative seroprotective titer of ≥40 for HAI and MN. The primary clinical outcome was mild-to-moderate influenza disease (MMID), defined as ≥1 postchallenge positive qualitative RT-PCR test with a qualifying symptom/clinical finding. Results Of 76 participants given influenza virus challenge, 54 (71.1%) experienced MMID. Clinical illness was generally very mild. MMID attack rates among participants with baseline titers ≥40 by HAI and MN were 64.9% and 67.9%, respectively, while MMID attack rates among participants with baseline titers & lt;40 by HAI and MN were 76.9% and 78.3%, respectively. The estimated odds of developing MMID decreased by 19% (odds ratio, 0.81 [95% confidence interval, .62–1.06]; P = .126) for every 2-fold increase in baseline HAI. There were no significant adverse events. Conclusions We achieved a 71.1% attack rate of MMID. High baseline HAI and MN were associated with protection from illness. Clinical Trials Registration. NCT04044352.
Type of Medium:
Online Resource
ISSN:
0022-1899
,
1537-6613
DOI:
10.1093/infdis/jiad021
Language:
English
Publisher:
Oxford University Press (OUP)
Publication Date:
2023
detail.hit.zdb_id:
3019-3
detail.hit.zdb_id:
1473843-0
