We must guard ourselves against anger, sadness, fear, worry, and pensiveness, but we should amuse ourselves and take pleasure in sweet songs, entertaining stories, and other similar things.
We should abstain from sex, if not completely, then mostly, and in such times it is not good to take a wife in marriage. Also, it is not good to have political conversations, that is, conversations about civic affairs, especially with people who are ill, or those who are prone to illness.
Pietro da Tossignano, Consiglio per la peste
Spittle-flecked political conversations: a suspected cause of contagion since the 15th century.