As many as 57 staff includingnurses were quarantined at two civic-run hospitals in Mumbai on Wednesday after a patient each tested positive there, Brihanmumbai Municipal Corporation (BMC) sources said.Further, the BMC also ordered suspension of emergency and OPD services at two private hospitals after a few patients at these hospitals tested positive for coronavirus infection, sources said.According to union sources, at least 40 staff including nurses and doctors were quarantined at KB Bhabha Hospital in Bandra.The staff had earlier stopped work and protested after a woman admitted on April 4 tested positive for COVID-19.Further, at least 17 cleaning staff at KEM Hospital were quarantined after a 50-year-old sweeper tested positive.OPD and emergency medical services were stopped at Bhatia hospital in Grant road area and another private hospital in Khar after COVID-19 cases were found there.Bhatia hospital said in a statement that three patients were found to be COVID-19 positive. As a precautionary measure, BMC officials collected swab samples of around 70 staff, and results were awaited.A senior citizen tested positive at the private hospital in Khar area, and as a precautionary measure new admissions at the hospital have been stopped.A staff at private-run Breach Candy hospital also tested positive to COVID-19 but it is not yet known if the BMC has quarantined any other staff or asked the hospital to take any preventive measures.The civic body has already sealed two prominent private hospitals, namely, Jaslok and Wockhardt, after several staff were found to have contracted virus.