It is surprising how many of those viruses animal studies have indicated could be treated with a large dose of Quercetin, a common component of fruits and vegetables that most people eat some of daily. The typical amount of Quercetin eaten by Americans is 25 to 100 mg per day. The animal studies hint that as an anti-viral about 4000 to 8000 mg of Quercetin is needed per day.

The Canadians and Chinese were going to do a joint clinical trial of Quercetin on Covid-19 SARS2 virus on Chinese patients earlier in the year.

What happened that stopped the Quercetin trial was kinda crazy.

A vice president of Huawei the Chinese 5G telephone equipment company was visiting Canada.
The USA asked the Canadians to arrest and hold this female Huawei VP for spying, which was done.
The Chinese then arrested dozens of Canadians in China,
including the Canadian scientists doing the Quercetin trial,
and held them as hostages.
The Quercetin trial was abandoned.

Recently a deal was done with the Huawei VP where she pleaded guilty to a minor criminal charge, was then released and allowed to return to China from Canada.