New Delhi, Aug 31 : Former President Pranab Mukherjee's health deteriorated on Monday and he is in a septic shock due to lung infection, the Army Research and Referral Hospital said. He has been hospitalized for the past 21 days and been critical following a brain surgery. The hospital authorities stated: "There is a decline in the medical condition of Pranab Mukherjee since yesterday." The doctors further pointed out that he is in septic shock due to his lung infection and is being managed by a team of specialists. "He continues to be in a deep coma and on ventilator support," the authorities said. There was a slight improvement in Mukherjee's health condition last week thereafter it deteriorated when he developed lung infection. Mukherjee was also found to be Covid-19 positive when he was admitted on August 10 for life-saving emergency surgery for a brain clot. There has been no improvement in his health status since. The veteran leader was admitted to the hospital at 12.07 p.m. on August 10 in a critical condition. /IANS