I think I found the study - OR NOT. https://www.nih.gov/news-events/nih...samples,coronaviruses that cause common colds.
Google Maps now shows you COVID-19 stats The app's 'COVID layer' will display the seven-day average of new cases. https://www.engadget.com/google-maps-now-shows-you-covid-19-stats-173343901.html
Sounds like nonsense to me. I am not aware of any beach where people are not allowed in the water due to COVID. Nor does a search of news stories reveal any. Can you point to an example? What beach is this tweet from? Of course the tweet is from a Twitter account that simply spreads conspiracy theories about COVID. There are numerous beaches for water entry closed due to pollution/waste plant spills, aquatic issues (plant/animal threats e.g. jellyfish), weather/surf conditions, or not having lifeguards staffed past Labor Day. Not a single one closed for water entry due to COVID.
I'm not surprised you think it is nonsense. It works counter to what you want the world to look like. I'll channel my inner GWB and just say "why don't you go review the tweets by this individual?"
Unless you can provide the name of the beach where people are not allowed in the water due to COVID then it is pure nonsense.