Some things, like echinace…
Some things, like echinacea, simply destroy virions outright. They're rare.
Others are protease inhibitors. They (temporarily) prevent viral replication inside cells. Zinc+quercetin does this.
Others bind to the viral spikes to prohibit cellular entry. Elderberry does this. 2/
— Adam Gaertner (@veryvirology) April 1, 2020