If a child has a fever after a chickenpox vaccination, the following measures can be used: 1. Give the child more warm water, because the child’s body water consumption after a fever is relatively large, it is necessary to timely replenish warm water. 2. Give antipyretic drugs. If the child’s fever exceeds 38.5℃ under the armpit, headache, weakness and poor mental state will appear, the child can be given antipyretic drugs such as acetaminophen or ibuprofen to reduce fever. 3. If the fever lasts for a long time, more than 3 days, children can be treated with anti-viral Chinese medicines such as Blue Scutellaria Oral Liquid.