As well as being a reality TV star, Mike was a professional soccer player, playing for clubs including St Albans and Chelmsford. He appeared on Love Island in 2017.
His season of Love Island is broadcast in Australia by Channel 9 on 9Now.
Mike got his fame by dubbing the nickname “Muggy Mike” on the show. After his death, co-star Chris Hughes asked people to stop using this name.
“His name wasn’t Muggy Mike. Please stop brandishing that. His name was Mike Thalassitis, and every inch of my heart goes out to his family & friends. A good guy, taken far, far to soon,” Chris tweeted.
More of Mike’s co-stars and friends have shared tributes on social media.
Last year, a contestant from the 2016 series of Love Island, Sophie Gradon, died aged 32.