Guy Nougher was charged following the incident in Hythe High Street on Saturday 13 June 2020.
The 62-year-old, of Military Road, Hythe, admitted charges of affray and assault and was given a 21-month sentence at Canterbury Crown Court on Wednesday 25 November.
Nougher was seen kicking the door of a building society on the day of the offence and was told to stop by a member of the public who was passing by.
Nougher then made threats to punch the man and pushed him with a clenched fist. When the victim asked him to stand back, Nougher told him: ‘I have got Covid.’ He then spat in the man’s face.
He was arrested the following day and enquiries confirmed he had been told he had tested positive for the virus on Wednesday 10 June, three days before the incident.
The victim had to self-isolate following the incident but later tested negative for Covid-19.
Kent Police’s Inspector James Wyles said: ‘Nougher should have been self-isolating at the time of this incident, following his positive test, but instead he went out and committed this callous offence.
‘The circumstances must have been extremely worrying for the victim and I hope our investigation, and the sentence which has been handed down, will give him a sense that justice has been done.’