The simplified answer to this question is.
Is it legal to punch someone who coughs on you. If someone intentionally coughs on you like this person did to Juan and they dont have the coronavirus they should be arrested and. For PlayStation 4 on the PlayStation 4 a GameFAQs message board topic titled If someone Spits on you are you Legally allowed to Punch them in the face - Page 17. The act of coughing or spitting on another person in order to expose them jokingly or not to COVID-19 has already been the cause of multiple arrests around the US.
That would make you the aggressor. The risk of death is definitely non-zero. Use of a punch by you was not justified.
However self defense is a defense to an assault charge. If a reasonable person would think that physical harm is in the immediate offing the defendant can typically use reasonable force to prevent the attack. People dont have to wait until theyve actually been struck to act in self-defense.
Do not punch someone here unless you seriously want to incapacitate them. In law you wouldnt have a defense but the police will only prosecute if its in the public interest and prosecuting you for hitting someone who spat at you probably wouldnt be seen as in the public interest. If someone gets in your face without touching you you might be allowed to use force but it depends on the circumstances.
What you SHOULD do is get that stuff off your body as quickly as possible. For example if someone runs up to you in the street and punches you then runs away you are not legally allowed to run after them just so you can punch them back. Another example of this would be if someone throws a drink over you at a party you are not allowed to react by hitting them.
Similarly punching someone who has hit you first is only lawful if the purpose of your punch is to stop them hitting you again or to place them under arrest for the crime of hitting you - if they hit you and ran away you. If you punch someone in the face in response to being coughed on theres a good chance youll be charged with assault and that the justification defense will not work for you. Yes coughing on someone to expose them to illness is assault.