LONDON (Reuters) - Many 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. Doctors and scientists around the world urgently need to investigate the causes and identify new treatments for mental illness after COVID-19, Harrison said. “(Health) services need to be ready to provide care, especially since our results are likely to be underestimates (of the number of psychiatric patients),” he added.