The flu vaccine can give children the flu

What the research found

Australian health guidance says the flu vaccine cannot give your child the flu. The injected vaccine does not contain live virus. It contains an inactive part of the virus that trains the immune system to recognise and fight the infection.

Side effects are usually mild. Pain and redness at the injection site are most common. Less often, children get a fever or aches lasting one or two days. Guidance says fewer than 1 in 6 people have side effects, which can feel like early flu and pass within a couple of days.

Children aged 2 to under 18 can also be offered a nasal spray vaccine made from live attenuated (weakened) virus. A 2021 meta-analysis found it linked only to runny nose, blocked nose and sore throat compared with placebo. A 2020 trial in children aged 3 to 17 found more fever with the spray, especially at ages 3 to 9. Serious adverse events were judged unrelated to the vaccine.

What it doesn’t mean

• The vaccine does not always prevent flu, so a vaccinated child can still catch it. That does not mean the vaccine caused it.
• In a Bangladesh trial of the nasal spray in children aged 24 to 59 months, 45% and 67% of vaccinated children shed two of the vaccine virus strains, and none shed the third. A separate trial of the spray in the same setting found reactions were similar to placebo.
• Call an ambulance (000) if your child has trouble breathing, swelling of the lips, tongue or throat, or faints. Speak to your child's doctor if side effects worry you.