Khan, 67, agreed for the test after Faisal Edhi, the son of late philanthropist Abdul Sattar Edhi and chairman of the Edhi Foundation, who met him last week tested positive for the coronavirus.
Imran believes three people -- Prime Minister Shehbaz Sharif, Interior Minister Rana Sanaullah and Major General Faisal (Naseer) -- were involved in the attack on him.
Khan's spokesman Dr Shehbaz Gill said that the prime minister has just a slight fever and cough.
Khan said he was hit by four bullets on his right leg during the assassination attempt.