Absolutely nothing unexpected. Stock markets, especially in China and Asia, will react very strongly to coronavirus, and European and American too.
Bitcoin now looks like a safe haven, for pumping money from exchanges, and waiting for all the events with the coronavirus.
Everything reacts to coronavirus. I did my TOEFL recently and saw an article that the tests are canceled in China. I have sort of a job in film industry, and today I read that China closing 70k cinemas due to the virus will cost the global economy about $1 billion! Fortunately, Bitcoin does not get affected, because it certainly cannot spread the disease and using it does not require attending any public places where someone might be infected.
As for transaction volume, though, I don't believe the data because everyone knows about volume getting faked and because I cannot find any well-established media writing about it.