As if Covid-19 were not bad enough, depression preceded by problems with mood, sleep, anxiety, and fatigue follow the infection in a significant proportion of people, a new paper suggests. Half of nearly 4,000 people who responded to an online survey — whose topic was disclosed only after entering — met criteria for moderate or more severe depression. People who reported headache as a symptom during their illness were more likely to have depressive symptoms; loss of smell and taste were not linked.