Vaccine and Clinical Trials

Adverse effects of Vaccination

Submit Abstract Register Now

Vaccines, though they are designed to protect from disease, can cause side effects, just as any other medication. Most side effects caused by vaccinations are mild, such as soreness, swelling, fever, achiness. The side effects usually last for a couple of days and the pain near the injected area will last for 3-4 days. Common and moderate side effects are a sign that vaccines are working and not experiencing any side effects does not mean that the vaccine is ineffective. Everyone has a different immune response and it means everybody responds differently. Adverse effects are rare but may include seizure or life-threatening allergic reaction, severe infection beginning at the vaccination site, encephalitis (severe brain reaction), and death (1-2 per million, mostly in people with weakened immune systems).

Related associations and societies: National Institute of Allergy and Infectious Diseases (NIAID), Hepatitis B Foundation (HBF), National Institutes of Health (NIH), Federation of Clinical Immunology Societies (FOCIS), Immune Deficiency Foundation (IDF),  Asia Pacific Association of Allergy, Asthma and Clinical Immunology (APAAACI), Clinical Immunology Society,Pediatric Infectious Diseases Society(PIDS), Indian Vaccine Manufacturers Association (IVMA), National Medical Association (NMA).