You can take a shower 24 hours after the flu vaccination. After the flu vaccination, there will be pinholes at the local injection site, and generally the pinholes can be completely closed after 24 hours, so you can take a shower after 24 hours. If you take a shower too early, it may cause skin infection at the local injection site. In addition, there will be local redness, swelling, pain and hard knots after injection, so taking a bath too early can aggravate the local reaction. After vaccination, the immunity can be low, so it is important to take rest and avoid exertion after vaccination. Bathing is also physically demanding and can cause symptoms such as colds and colds, and can also cause fever. The side effects of the flu vaccine itself can also cause symptoms such as fever, headache, sore throat, nasal congestion, and runny nose. If fever occurs after taking a bath, it may cause some difficulty in diagnosis.