COVID-19 survivors are likely to be at greater risk of developing mental illness, psychiatrists said on Monday, after a large study found 20% of those infected with the coronavirus are diagnosed with a psychiatric disorder within 90 days.Anxiety, depression and insomnia were most common among recovered COVID-19 patients in the study who developed mental health problems, and the researchers also found significantly higher risks of dementia, a brain impairment condition.“People have been worried that COVID-19 survivors will be at greater risk of mental health problems, and our findings … show this to be likely,” said Paul Harrison, a professor of psychiatry at Britain’s Oxford University.