Veteran ABC health presenter Norman Swan says he has filled a "vacuum" left by the government's poor communication on the coronavirus crisis, accusing health authorities of putting out "public relations Valium".

The broadcaster of nearly 40 years, who is a doctor by training, has become a beacon of guidance for many confused and concerned listeners. But he says he has never sought to portray himself as an official spokesperson or adviser on managing the pandemic.

Norman Swan, a physician by training, has presented Radio National's Health Report for the past 35 years.

"There's something wrong with the system if it's me that people are relying on," Dr Swan said.

"You see all these Twitter messages saying 'Norman for chief medical officer'. Thanks very much, but no. I don't want to be the national spokesperson for coronavirus. My job is to hold the government to account."