When Dr. Mohamed Salah Siala began working on the COVID-19 front line in January in a Tunisian hospital he never imagined harnessing his music skills in the fight against the virus. Yet when the 25-year-old decided to get out his violin one day at Hedi Chaker Hospital in the city of Sfax and play, it won praise for boosting the morale of virus sufferers who remained isolated and needed a smile.