New Delhi, April 1 : Days after two Mohalla Clinic doctors got coronavirus infection, another doctor in the city has tested positive to COVID-19, resulting in shutting down of the Delhi State Cancer Institute for sanitisation. According to the hospital administration, the doctor got the infection from relatives who returned from abroad. "The hospital, including the OPD, has been closed for sanitisation," an official said. The hospital is also contacting the patients who came in contact of the doctor and asking them to get quarantined. This is the third case of a doctor getting the infection. Before this, two doctors of the Mohalla Clinic -- in Babarpur and in Maujpur -- were tested positive for coronavirus. The authorities had asked their patients for self-quarantine at home. Delhi's coronavirus patient count has reached 120, with 49 people having travel history to foreign countries. /IANS