Human viral challenge studies are generally developed to quickly test efficacy of vaccines, prophylactics and treatments in a relatively small number of participants compared to Phase 2a/b field studies. hVIVO has developed multiple challenge agents for use in humans and have collated data on RSV, influenza, and SARS-CoV-2. In addition to typical measures of disease (temperature, symptoms, directed physical exam, tissue mucous weights and counts), some participants have been given daily cold perception questionnaires. Here we present the incidence of participant perceived colds, when they occur, and how this may impact the ability to use this measure for vaccine and treatment efficacy testing as well as for triggering treatment.
