Serotonin is elevated in COVID-19-associated diarrhoea. Issue 10 (5th January 2021) - Ha, Seeun; Jin, Byungchang; Clemmensen, Brooke; Park, Paul; Mahboob, Sumaiya; Gladwill, Vadim; Lovely, Farah Madhani; Gottfried-Blackmore, Andres; Habtezion, Aida; Verma, Subhash; Ro, Seungil