Not sure what you mean by “no evidence.) Tho it may be difficult to quantify, seems numerous sources indicate there is asymptomatic evidence...the percentage varies.
https://www.webmd.com/lung/qa/what-is-asymptomatic-transmission
Asymptomatic means no symptoms. When someone has an infection, there is a period of time after they catch the germ before they have symptoms. This is called the incubation period. In some cases, people may catch the infection and never have any symptoms. Even with no symptoms, it’s possible to spread an infection. For example, the flu is contagious a day before someone develops symptoms. For COVID-19, the disease caused by the novel coronavirus, it’s most contagious when someone has symptoms, but it’s still possible to spread the infection from person to person even with no symptoms.
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https://www.webmd.com/lung/news/20210110/59-percent-of-covid-cases-stem-from-asymptomatic-spread
Jan. 11, 2021 More than half of all COVID-19 cases transmit from people who don’t have any symptoms, according to a model developed by CDC researchers.
About 59% of transmission comes from people without symptoms, according to a new study published Thursday in JAMA Network Open. This includes 35% from people who infect others before they show symptoms and 24% from people who never develop any symptoms.
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https://www.nature.com/articles/d41586-020-03141-3
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https://www.bmj.com/content/371/bmj.m4851
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https://www.pnas.org/content/118/9/e2019716118
Thanks for links.