Question:
What’s the source (other than derech eretz, and if it’s only derech eretz, what’s the source) for covering one’s mouth when sneezing or coughing to prevent the spread of germs that can cause illness? There’s a gemorah in Berachos 24b on top about covering chin/mouth for a yawn. I heard there’s a Rosh that this also refers to coughing/sneezing…is it only during Shemoneh Esray or can one infer that covering of the mouth should be covered in all situations?
Answer:
Hello,
Aside from spreading germs, the gemora (Chagiga 5a) relates that there are acts that one may do in private, when one thinks no one is looking, but if someone sees it and is revolted by it, Hashem will hold it against him, for causing the other person pain! The two examples given there are a person who kills a louse in front of others, or a person who spits in front of someone else and disgusts him with it. Many people would likewise be disgusted by seeing someone sneeze and not contain the sneeze.
Regarding the Rosh, what you are referring to is the commentary of Tiferes Shmuel on that Rosh, who says that even if it isn’t in front of other people, during Shemona Esrei on should cover their mouth when yawning or sneezing, see Kaf Hachayim O:CH 97-3.
Sources:
תלמוד בבלי מסכת חגיגה דף ה עמוד א
רבי יוחנן כי מטי להאי קרא בכי. כי את כל מעשה האלהים יבא במשפט על כל נעלם, עבד שרבו שוקל לו שגגות כזדונות תקנה יש לו? מאי על כל נעלם? אמר רב: זה ההורג כינה בפני חברו ונמאס בה. ושמואל אמר: זה הרק בפני חבירו ונמאס. רש”י מסכת חגיגה דף ה עמוד א
ונמאס – קצה דעת חבירו בדבר.
