The Mountain Goats frontman John Darnielle is the latest musician to contract COVID-19, confirming his diagnosis is an ad-libbed acoustic “song”.In the four-and-a-half-minute performance – partly sung, and partly delivered in frantically spoken explanations – Darnielle assured fans that he tested negative for the virus on the last date of The Mountain Goats’ three-show run in North Carolina (on December 18). The following day, however, the singer-songwriter noted that he felt unusually fatigued,