SINGAPORE : A migrant in Singapore who self-harmed and was pictured bloodied in a stairwell has heightened concerns over the mental health of thousands of low-paid workers confined to dormitories in the city-state due to the COVID-19 pandemic.In April, Singapore sealed off sprawling housing blocks where its vast population of mainly South Asian labourers live in crowded bunk rooms, in an effort to ring-fence a surge in virus cases among the workers.Four months on, some dormitories remain under quarantine, and even migrants who have been declared virus-free have had their movements restricted and face uncertainty over the jobs on which their families back home depend.Rights groups say this has taken a heavy mental toll on workers, pointing.