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Which side effects can occur after smallpox vaccination?
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smallpox
Edward Jenner vaccinating his child against smallpox; colored engraving.
Most individuals who receive the smallpox vaccine experience only mild side effects. Common reactions include soreness, redness, swelling, or itching at the vaccination site, as well as fever, headache, body aches, fatigue, and swollen lymph nodes.12
Some individuals, particularly those with weakened immune systems or certain skin conditions, are at risk for rare but serious complications. These may include:
- Severe skin reactions: Such as eczema vaccinatum.12
- Cardiac inflammation: Including myocarditis or pericarditis.12
- Neurological issues: Such as brain inflammation (encephalitis).12
- Progressive vaccinia: The development of a nonhealing, worsening sore at the vaccination site.12
- Allergic reactions: Severe systemic responses.1
Additionally, there is a risk of spreading the vaccinia virus if the vaccination site is touched and the virus is subsequently transferred to other parts of the body or to other people.1