My son has peanut and tree nuts allergies. We told the JetBlue flight attendant at the gate and she relayed the message to the other flight attendants. When we boarded, they had clearly wiped down the three seats in our section; you could smell the product when we boarded.
They then talked to the row before us, our row and the row behind us saying there is someone in the rows around you with a severe peanut allergy. Please refrain from eating them during the flight. If you have some, we will ask the person if it is ok for you to eat it or not. If not, we will give you another option of food. One person did tell the attendant and they came to ask us if it was ok for the person to eat it. Super considerate! I would definitely fly them again even if the flight is more money than on another airline flying the same route..