https://www.wired.com/story/the-search-for-a-covid-19-research-animal-model/

Early in the morning, the day after Mardi Gras in New Orleans—an explosion of humanity unimaginable today, though it was only two months ago—a FedEx truck pulled up to a loading dock at Tulane University. Two people stood waiting. The driver pulled a cardboard box out from among the orders of shoes and toilet paper, and delivered it to the woman leading the pair. It contained a frozen vial filled with millions of particles of SARS-CoV-2, the virus that was at the same time silently making its way through the city all around them.

This sample was isolated and propagated from a patient in Seattle, and was bound for the Tulane National Primate Research Center. There, it would be used to infect a group of four Rhesus macaques and four African green monkeys, to see if they could replicate the human disease—one of the first such experiments in the US. The highest-profile vaccine and treatment trials done on animals (including tests of the antiviral drug remdesivir) have been conducted only in Rhesus macaques, one of the most plentiful species of laboratory monkeys. But macaques have so far shown mostly mild symptoms after coronavirus infection. This is still useful—scientists can measure viral replication and see signs of infection. But animals with more severe symptoms make it easier to measure the effect of interventions, like vaccines or antiviral drugs.