What are the side effects of Group A meningococcal polysaccharide vaccine?
Dec 02, 2025
Source: Cainiu Health
Dr. Li Feng
Introduction
Side effects of the group A meningococcal polysaccharide vaccine include local redness, swelling, pain, low-grade fever, fatigue, headache, gastrointestinal discomfort, and allergic reactions. Most side effects are mild and transient; close observation is recommended after vaccination. If severe symptoms such as persistent high fever, severe rash, or difficulty breathing occur, prompt medical attention is advised. Mild redness, swelling, and induration at the injection site are common.
Side effects of the Group A meningococcal polysaccharide vaccine include local redness, swelling, and pain; low-grade fever; fatigue; headache; gastrointestinal discomfort; and allergic reactions. Most side effects are mild and short-lived. Close observation is recommended after vaccination. If severe symptoms such as persistent high fever, serious rashes, or difficulty breathing occur, prompt medical attention is advised.
1. Local redness, swelling, and pain: Mild redness, swelling, or induration at the injection site is common, often accompanied by brief pain. These usually appear within 24–48 hours after vaccination and resolve spontaneously within 1–2 days without special treatment.
2. Low-grade fever: Some individuals may experience a mild fever with body temperature generally not exceeding 38.5°C. It typically lasts 1–2 days and is usually a normal immune response to the vaccine. Adequate hydration and rest are sufficient for recovery.
3. Fatigue and headache: A small number of people may experience mild fatigue, dizziness, or headache, typically appearing 1–3 days after vaccination. Symptoms are generally mild, do not interfere with daily activities, and resolve with rest.
4. Gastrointestinal discomfort: In rare cases, individuals may experience nausea, loss of appetite, or mild diarrhea. Symptoms are usually short-lived and gradually improve by avoiding greasy foods.
5. Allergic reactions: Rarely, rashes or itching may occur. Severe allergic reactions, such as laryngeal edema, are extremely uncommon. Individuals should remain on-site for observation for 30 minutes after vaccination before leaving.
After vaccination, keep the injection site clean and dry, avoid contact with water for 24 hours, and refrain from scratching the area. Drink plenty of warm water, maintain a light and easily digestible diet, and avoid spicy or irritating foods. Ensure adequate rest and avoid strenuous physical activity to help the body smoothly pass through the period of immune response.
