As we have observed in the Covid-19 pandemic, It could be the case that you were just only lightly sick but also contagious. Not to mention also a few things ar

As we have observed in the Covid-19 pandemic, It could be the case that you were just only lightly sick but also contagious. Not to mention also a few things are difficult to pass, for example, University lectures (skipping one can make it difficult to follow the next) and again lecture halls are cramped so you can easily infect somebody.