Fever after a yellow fever vaccine

A raised temperature, tiredness, headache, muscle aches, or soreness around the injection site can occur after vaccination. These symptoms should be considered alongside their timing, severity, and whether they are easing. A fever can also arise from an unrelated illness that happens around the same time, such as a common cold or COVID-19.

Record the vaccine name, the day it was given, your temperature if measured, and any other symptoms. That information helps a clinician judge whether the pattern fits an expected reaction or needs investigation.

Rest, drink fluids, and wear light clothing if you feel hot. Use a fever medicine only if it is suitable for you and follow the packet directions or advice from your pharmacist or clinician. Avoid taking extra doses from combination cold and flu products. Keep the vaccination record available if you need to speak with a healthcare professional.

Seek emergency care for breathing difficulty, swelling of the face or throat, widespread hives, collapse, confusion, a seizure, or severe drowsiness. Contact a clinician promptly for a high or persistent fever, worsening weakness, repeated vomiting, severe headache, rash, or a fever that begins with symptoms suggesting another infection. Young infants and people with immune conditions need individual advice.

Ask which reactions are expected after your particular vaccine, which symptoms warrant urgent review, and whether any medicines or medical conditions change the advice. Mention recent travel, sick contacts, and all symptoms rather than assuming the vaccine is the cause.