What are the adverse reactions of the EV71 vaccine?

EV71 vaccine refers to the inactivated Enterovirus Type 71 (EV71) vaccine. Adverse reactions associated with the inactivated EV71 vaccine include local redness, swelling, and pain; mild systemic fever and fatigue; gastrointestinal discomfort; allergic reactions; and local induration with itching. Most of these reactions are mild and transient, requiring no special treatment. However, if severe allergic reactions, persistent high fever, or worsening symptoms occur, prompt medical attention is recommended.

1. Local redness, swelling, and pain: Mild redness, swelling, pain, or aching at the injection site is common and typically appears within 24–48 hours after vaccination. Symptoms usually resolve spontaneously within 1–2 days. Avoid scratching or pressing on the injection site.

2. Mild systemic fever and fatigue: Some individuals may experience low-grade fever (generally not exceeding 38.5°C), along with mild fatigue or dizziness. These symptoms typically last 1–3 days. Drinking plenty of water and getting adequate rest generally restores normal condition.

3. Gastrointestinal discomfort: A few individuals may experience nausea, vomiting, diarrhea, or loss of appetite. These are usually transient reactions. Eating light, easily digestible meals and avoiding greasy, raw, or cold foods can help reduce discomfort.

4. Allergic reactions: Rarely, rashes or urticaria may occur, typically developing several hours to days after vaccination. Mild cases often resolve spontaneously. However, if the rash spreads or worsens, timely medical evaluation is advised.

5. Local induration and itching: Some recipients may develop hard nodules at the injection site, accompanied by mild itching. These usually resolve gradually within 1–2 weeks. Avoid applying heat or rubbing the area to prevent aggravating local reactions.

Remain under observation at the vaccination site for 30 minutes after inoculation. After returning home, keep the injection site clean and dry, and avoid soaking it excessively during bathing within 24 hours. Drink plenty of water, ensure sufficient sleep, and maintain a light diet, avoiding spicy or irritating foods to help the body smoothly pass through the post-vaccination reaction period.