If you are fully aware of the fact that you have some kind of bug, virus or infection but still want to get high, it’s your responsibility to ensure you do not pass your nastiness on to others. Even if they seem more than willing to smoke with you, it is you that needs to take the responsibility for ensuring you do not infect the whole stoner circle. For example, passing joints while suffering a bout of flu or a cold is a sure-fire way of passing it on to at least a few of those around you. And just for the record, pretending you are fine when you actually know you are suffering like crazy just to convince them to smoke with you is a big no-no.