What are the side effects of the influenza vaccine?

Influenza vaccines are very safe.

 

Common side effects from the inactivated influenza vaccine include soreness, redness and swelling where the vaccine was given. Other symptoms, that may last 1 to 2 days, can include fever, headache, muscle soreness, fatigue, nausea, vomiting, diarrhea and chills. Babies and young children may be irritable, sleepy and have a decreased appetite. Fewer than 1 in 20 people may have oculo-respiratory syndrome (ORS). Symptoms of ORS include red eyes, a cough and/or sore throat and/or hoarseness.

 

The live attenuated influenza vaccine contains weakened influenza viruses and may cause mild influenza symptoms but these are much milder than those due to influenza infection. Symptoms may include a runny or stuffy nose, cough, sore throat and fever. Other symptoms can include headache, decreased appetite, weakness, muscle soreness, chills, vomiting, stomach ache and irritability.

 

Many people experience no side effects from influenza vaccines.

 

Serious side effects after influenza vaccination, like a severe allergic reaction, are very rare.