evidence: Moderna Therapeutics begin the first human trials of a vaccine to protect against COVID-19 at a research facility in Seattle, Washington. [...] HHS announces that COVID-19 vaccines will be provided free of charge to older adults and other groups experiencing disproportionate impacts from the COVID-19 pandemic. [...] CDC finds that the Pfizer-BioNTech and Moderna mRNA COVID-19 vaccines reduce the risk of hospitalization with SARS-CoV-2 in people ages 65 years and older by 94%.