Reactions to Vaccines in Babies

Vaccinations are critical to preventing disease and are an essential part of your baby's health care. Though some babies can have reactions to vaccines, such as tenderness at the injection site or a fever, these are generally mild and short-lived. A serious allergic reaction is possible, but rare.

In most babies, the pros of vaccines far outweigh the cons—including possible reactions. If your child has a health concern that would make vaccine inadvisable, your pediatrician will let you know.

This article discusses a baby's common reactions to vaccines and the signs of a serious allergic reaction. It also covers when to seek emergency care and when to avoid or postpone vaccinations.

Common Reactions to Vaccines

It is not unusual for babies to have side effects after getting a vaccination. Most are not all that serious and usually resolve within a day or two. The most common ones include:

• Tenderness, redness, or swelling at the injection site
• A slight fever
• Irritability
• Crying

Breastfeeding or bottle-feeding after an injection may help calm a fussy baby.

It may help to keep a bandage on the injection site for a few days as a visual reminder that the area may be sore.

Signs of a Serious Reaction

While rare, serious allergic reactions to infant vaccines have been known to occur. If not treated immediately, it could lead to a potentially life-threatening allergic reaction known as anaphylaxis.

Over the course of minutes to hours, the symptoms can worsen as the airways become increasingly constricted, leading to respiratory distress and other serious side effects.

Most cases of anaphylaxis occur within eight hours of getting a shot but can happen in less than 30 minutes. If left untreated, anaphylaxis can lead to unconsciousness, seizures, shock, coma, and even death.

Estimating Risk

Anaphylaxis can occur in response to any medication. While the possibility is worrisome, it should not cause you to avoid vaccinating your child. Research has shown that the risk is extremely low.

A 2016 study from the Centers for Disease Control and Prevention (CDC) reviewed data from the Vaccine Safety Datalink and confirmed that there were just 33 cases of anaphylaxis out of 25,173,965 vaccine doses administered from January 2009 to December 2011.

Based on their findings, the CDC researchers concluded that the risk of vaccine-triggered anaphylaxis is rare for all age groups.

When to Postpone or Avoid a Vaccination

As a general rule, infant immunizations are safe and a vital component of your child's good health. There are certain circumstances in which it may be necessary to skip or delay a shot, however:

• If an infant has a fever, they shouldn't receive a vaccination until they're completely recovered. It is safe to vaccinate a child with a cold, however.
• If an infant has had a previous allergic response to a vaccine, it's important to seek expert consultation with an allergist to identify the cause. This can help determine which vaccines are safe or unsafe for use.

Any infant with fever or illness should be evaluated by the doctor before receiving any vaccine.

Vaccines Doctor Discussion Guide

Get our printable guide for your next doctor's appointment to help you ask the right questions.

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