This is a great question. The answer is that it depends, of course. If the immunity that is granted by infection with the virus the first time is sufficient keep viral load low in the patient on their second infection, I would expect this to have an impact on transmission. If it simply alleviates symptoms but the viral load is still over the threshold for transmission, it won't prevent it. We will learn more about this when we have vaccine trial data.
If a person has an immune response that doesn't sterilize, but does prevent COVID-19 from developing, is it still possible for them to infect others?
This is a great question. The answer is that it depends, of course. If the immunity that is granted by infection with the virus the first time is sufficient keep viral load low in the patient on their second infection, I would expect this to have an impact on transmission. If it simply alleviates symptoms but the viral load is still over the threshold for transmission, it won't prevent it. We will learn more about this when we have vaccine trial data.