Childhood immunization has become a standard part of healthcare to mitigate known diseases. Still, vaccines of all kinds can also carry risks to your child. Detecting true vaccine injury in children can be complicated because many events may occur coincidentally after vaccination. So, how can a parent know how to identify vaccine injuries and when or when not to be concerned if their child experiences a physical or behavioral change after one of these vaccination events?
What Are Common Childhood Reactions to Vaccines?
To answer this question, we’ll look at the most common reactions children receive as part of the immunization process and how they can be addressed. These reactions include:
- Redness and/or pain and swelling at the injection site
- A mild fever that lasts 1–2 days
- A general sense of discomfort or fussy disposition
These are possible side effects that most children receive after vaccination.
These reactions usually go away on their own but can be helped along with a cold pack at the injection site or ibuprofen (6 months of age or older) or acetaminophen (age 2 months or older) to reduce pain. Sometimes gently moving a baby’s arms or legs (in a bicycle motion) to increase blood flow can help bring relief. Should you have any questions or concerns about these symptoms or their intensity or duration, you can always reach out to your child’s pediatrician.
There are some specific normal vaccine reactions beyond these that are associated with specific vaccines. Your doctor should prepare you for these at the time of the child’s immunization. For example, the MMR vaccine has been known to cause a fever and a rash that lasts 7–10 days after the shot—these are examples of vaccine reactions. The DTaP vaccine has also been reported to cause excess crying for several hours after injections.
Vaccine reactions can vary, however, from mild malaise to serious and life-threatening immune responses.
The first 2–7 days after a vaccine are when you want to be most diligent to notice any abnormal symptoms that could be related to the vaccination.
Serious Issues that Identify Vaccine Injuries
Contact your doctor if the following issues occur within 2 days of getting a vaccine. Parents should watch for severe symptoms and adverse events, as these may indicate a serious reaction:
- A High Fever: A fever of 100.4 degrees Farenheit or higher for babies under 3 months old and 101.5 degrees or higher for babies 3 months or older can be a cause for concern.
- Unusual Bleeding or Bruising: Bruising easily or bleeding from the gums, blood seen in their stool, or excessive bleeding after a minor injury is a reason to call your doctor.
- Atypical Crying: Crying for more than three hours at a time (after ruling out colic) or crying at a higher pitch than normal for more than one hour may be a sign of underlying issues that need to be addressed. Persistent crying may be associated with more serious adverse events.
- Nausea, Vomiting, or Diarrhea: If this is noticed, or reported by your child, call your doctor to let them know and closely monitor your child for any other concerning symptoms. If symptoms last for longer than 3 days, additional medical intervention may be necessary.
In some cases, vaccine injuries can result in life threatening illness.
It is important to monitor for any severe symptoms after vaccination, as adverse events can sometimes lead to serious complications. Brain damage is a serious potential outcome, and permanent brain damage has been reported following certain vaccines.

Call 911 if Your Child Experiences:
An Allergic Reaction
If you notice hives or swelling that is unusual this might be your child having an allergic reaction to the shot. Any potentially severe allergic reaction can lead to anaphylactic shock. A skin rash or eczema that lasts more than 2 days could also be an allergic reaction in progress.
Difficulty Breathing
This could be related to an allergic reaction or something else. If your child complains of having trouble breathing or is visibly laboring to take in breath, get them to a doctor immediately.
Seizure or Convulsions
Often linked to a high fever, any sign of a seizure or convulsion in your child warrants additional medical attention.
Uncoordinated Movement or a Loss of Vision
Sudden abnormal changes in the ability to move muscles with ease while walking or crawling or a sudden loss of vision require medical attention.
Abnormal Sensations (Numbness/ Tingling)
If your child reports any kind of unusual sensations in the body or skin and/or reports numbness or tingling beginning in the toes and fingers take action to have this investigated further.
Listlessness, Lethargy, or Unresponsiveness
Unusual energy levels of these kind and/or weakness in the arms and legs can be a sign of a negative reaction to the shot. A pale complexion might also accompany the weakness. Get help immediately if this applies.
Slurred Speech
If you notice any unusual speech patterns that could be cognitive or muscle related, these identify vaccine injuries that are much more serious and should be checked out by a doctor.
A Loss of Consciousness
Fainting or blacking out could be a sign of anaphylactic shock and needs to be urgently addressed. Don’t wait. Take fast action.
When you visit the ER to have the symptom(s) evaluated, be sure to specifically mention to your healthcare provider the vaccine event, date it occurred, and which vaccine(s) was administered.
Reporting an Adverse Reaction to VAERS (The CDC Reporting System)
While U.S. healthcare providers are required to report any and all suspected adverse events with vaccinations through the Vaccine Adverse Reporting System (VAERS) set up by the Centers for Disease Control and the Department of Health and Human Services, not all adverse events are properly reported. VAERS collects data on adverse events and possible adverse events following vaccination. Reports describe a range of reactions, from mild to severe, and VAERS data is used to monitor vaccine safety and identify signals that may require further investigation. Adverse events following immunization are reported by vaccine manufacturers, pharmacists, physicians, and parents to the FDA and CDC. The Department of Health and Human Services oversees VAERS and other human services related to vaccine safety. In addition to VAERS, the Vaccine Safety Datalink is another system used by the Centers for Disease Control and Health and Human Services to monitor vaccine safety in large populations. As you can imagine, this information is critical for determining safety protocols or warnings for vaccines overall.
Should your child suffer a vaccine related injury or reaction diagnosis, you can make an anonymous report yourself online HERE or by calling (800) 822-7967 to be sure a report is properly recorded. This will help others to identify vaccine injuries in the future.
How Do I Pursue Vaccine Injury Compensation?
If you identify vaccine injuries in your child from a routine immunization and you’ve received a medical diagnosis to support this, you may be eligible for compensation through the Vaccine Injury Compensation Program (VICP). This is a taxpayer funded program created by Congress specifically for individuals who have been injured or killed by certain vaccines. The National Childhood Vaccine Injury Act (NCVIA) was enacted in 1986 to address compensation for individuals harmed by vaccines.
Our team of experienced attorneys can assist you in obtaining vaccine injury compensation through this program as we’ve already done for hundreds of clients in all 50 states. Reach out today to let us help you obtain the compensation you deserve.