IMMUNIZATION REACTIONS Symptom Definition You believe your child is having a reaction to an immunization. Reactions to DTaP (Diphtheria, Tetanus, Pertussis), MMR (Measles, Mumps, Rubella), polio, Hemophilus influenzae type b, Hepatitis A, Hepatitis B, influenza, chickenpox (varicella)), pneumococcal and pneumococcusmeningococcal vaccines are covered. Most local pain and swelling at the injection site and fever occur within 2 days. Fever with most vaccines begins within 24 hours and lasts 2 to 3 days. With live vaccines (MMR and chickenpox), fever and systemic reactions usually begin between 1 and 4 weeks. Severe allergic reactions are very rare, but can occur with any vaccine WHEN TO CALL YOUR DOCTOR FOR IMMUNIZATION REACTIONS Call 911 Now (your child may need an ambulance) Difficulty with breathing or swallowing. Not moving or very weak.   Unresponsive or difficult to awaken . Call Your Doctor Now (night or day) If Your child looks or acts very sick. Age less than 12 weeks with fever above 100.4°F (38°C) rectally.  (Exception: occurs within 48 hours after DTaP shot.) Fever above 105° F (40.6° C) High-pitched, unusual cry present for more than 1 hour. Crying continuously for more than 3 hours. Redness or red streak around the injection site bigger than 1 inch.   Redness around the injection site persists for more than 48 hours (2 days). Call Your Doctor Within 24 Hours (between 9am and 4pm) If You think your child needs to be seen Fever present for more than 3 days Measles vaccine rash (onset day 6 to 12) persists for more than 3 days Call Your Doctor During Weekday Office Hours If You have other questions or concerns Pain, tenderness, or swelling at the injection site persists for more than 3 days • Fussiness from vaccine persists for more than 3 days Parent Care at Home If Normal immunization reaction and you don't think your child needs to be seen. Back to Top HOME CARE ADVICE FOR IMMUNIZATION REACTIONS Local Reaction to the Injection (all vaccines except oral polio): Pain:  For initial pain or tenderness at the injection site: Apply ice to the area for 20 minutes once. Give acetaminophen (e.g. Tylenol) or ibuprofen by mouth. Fever:  For fevers above 102°F (39°C), give acetaminophen (ok to use ibuprofen if older than 6 months old). General Reaction: All vaccines can cause mild fussiness, irritability and restless sleep. While this is usually due to a sore injection site, sometimes the cause is less clear. Some children sleep more than usual. A decreased appetite and activity level are also common. These symptoms do not need any treatment and will usually resolve in 24-48 hours. Call Your Doctor If Fever lasts more than 3 days. Pain lasts more than 3 days. Injection site starts to look infected. Your child becomes worse or develops any of the "Call Your Doctor" symptoms. Chickenpox Vaccine: Pain or swelling at the injection site for 1 to 2 days (in 19% of children). Fever lasting 1 to 3 days begins 17 to 28 days after the vaccine (in 14%). Give acetaminophen (e.g. Tylenol) or ibuprofen for fever above 102°F (39°C).  Never give aspirin for fever, pain or within 6 weeks of receiving the vaccine (reason: risk of Reye's syndrome - a rare but serious brain disease). Chickenpox-like vaccine rash (usually 2 lesions) at the injection site (in 3%). Chickenpox-like vaccine rash (usually 5 lesions) scattered over the body (in 4%). This mild rash begins 5 to 26 days after the vaccine and usually lasts a few days. Children with these vaccine rashes can go to day care or school (reason: for practical purposes, vaccine rashes are not contagious). EXCEPTION: avoid school if widespread, weepy lesions (reason: probably actual chickenpox). Precaution: if vaccine rash contains fluid, cover it with clothing or Band-Aid. DTaP or DT Vaccine:  The following harmless reactions to DTaP can occur: Pain, tenderness, swelling or redness at the injection site (in 25% of children) and lasts for 24 to 48 hours.Swollen arm or leg following 4th or 5th DTaP occur in 3% and is not serious. Fever (in 25% of children) and lasts for 24 to 48 hours . Mild drowsiness (30%), fretfulness (30%) or poor appetite (10%) and lasts for 24 to 48 hours. Hemophilus influenzae Type b Vaccine(HiB):  No serious reactions reported. Sore injection site or mild fever only occurs in 1.5% of children. Hepatitis A Vaccine: No serious reactions reported Sore injection occurs in 20% of children, loss of appetite in 10%, and headache in 5%. Usually no fever. If these symptoms occur, they begin 3-5 days after vaccine and last 1-2 days. Hepatitis B Virus Vaccine (HBV): No serious reactions reported. Sore injection site occurs in 30% of children and mild fever in 3% of children. Because fever from the vaccine is rare, any infant less than 3 months with a fever following the vaccine should be examined. Influenza Virus Vaccine: Pain, tenderness or swelling at the injection site occurs within 6 to 8 hours in 10% of children. Fever 101° to 103°F (38.4° to 39.5°C) occurs in 18% of children.  Fevers mainly occur in young children. Measles Vaccine: The measles vaccine can cause a fever (10% of children), and rash (5% of children) about 6 to 12 days following the injection.  The fever is usually between 101° and 103°F (38.4° and 39.5°C) and lasts 2 or 3 days.  The mild pink rash is mainly on the trunk and lasts 2 or 3 days.  No treatment is necessary.  Your child is not contagious. Call Your Doctor If: Rash becomes very itchy. Rash changes to purple spots. Rash lasts more than 3 days. Meningococcal Vaccine:  No serious reactions Sore injection site for 1 to 2 days is uncommon Mumps or Rubella Vaccine: There are no reactions except for an occasional sore injection site. Pneumococcus Vaccine: Pain, tenderness, swelling OR redness at the injection site in 15-30%. Mild fever below 102°F (39°C) in 15% for 1-2 days.       No serious reactions. Polio Vaccine: There are no serious reactions to oral polio vaccine.  Polio vaccine by injection occasionally causes some muscle soreness. Back to Top Disclaimer: This information is not intended be a substitute for professional medical advice. It is provided for educational purposes only. You assume full responsibility for how you choose to use this information. Pediatric HouseCalls Online. Copyright © 2000-2005 Barton Schmitt, M.D. FAAP Reviewed 8/2005 Revised 8/2005 View Index of Topics