Covid-19 positive test rates have hit a five-year Thanksgiving low going into the first holiday of the winter season, and respiratory disease levels of the flu and RSV are also at pre-pandemic lows, but the Centers for Disease Control and Prevention warns that trend is likely to reverse before Christmas comes around.

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On Wednesday, the CDC warned it expects to see an increase in Covid and RSV levels in the coming weeks as large gatherings, travel and more time indoors allow disease to spread more easily person-to-person. The CDC recommends opening windows and doors for ventilation, wearing masks in crowded areas, practicing regular handwashing and being up-to-date on Covid and flu vaccinations to avoid getting sick. RSV vaccines are recommended for all adults ages 75 and older, those between the ages of 60 and 75 who are at increased risk and pregnant women.

Thanksgiving travel is expected to finally rebound to pre-pandemic highs, according to AAA. Almost 2 million more people are expected to travel this year than last, with 79.9 million people venturing more than 50 miles away from home between the Tuesday before and Monday after the holiday. Car travel is expected to overtake pre-pandemic levels and air travel is expected to hit a new record for the holiday.