Though generally not severe, side effects can occur as a result of vaccine administration. The most common reactions are redness, swelling and pain at the injection site. Fever and behavioral changes such as poor eating may also occur. These usually occur within a few days of receiving the vaccination. Comfort measures such as Tylenol and a warm bath are often helpful. Motrin should not be given to infants under six months of age (CDC, 2014).
Live vaccines such as MMR and varicella may have a delayed reaction time of 5-60 days. Rashes may appear at the injection site or elsewhere on the body (CDC, 2014).
Rarely, severe complications such as anaphylaxis can occur. Usually, this is not from the antigen itself, but from things added during the production process such as gelatin or egg protein (CDC, 2014). Severe reactions can include hives, breathing difficulties, rapid heartbeat and swelling of the face or throat. If this occurs, instruct parents to call 9-1-1 or to go to the nearest hospital. The reaction should also be reported to the Vaccine Adverse Reporting system at www.vaers.hhs.gov or by calling 1-800-822-7967 (CDC, 2014).
Contraindications to Receiving Vaccinations
The most common reason vaccinations are withheld is for febrile illness. While it has not been shown that illness decreases the effectiveness of vaccines or increases serious side effects, it is recommended that children who are moderately to severely sick wait until the illness subsides before receiving a vaccination. Mild illnesses such as cold symptoms or ear infections are not contraindications (CDC, 2014).
A severe reaction to a prior dose of the vaccine or a component of the vaccination is always a contraindication. Vaccines may contain components such as neomycin, yeast, lactose, yeast or egg protein. Care must be taken to differentiate a mild or local reaction with a severe reaction, such as anaphylaxis (CDC, 2014).
If a vaccine contains pertussis, such as DTaP or Tdap, encephalopathy within seven days of a previous dose that cannot be attributed to another cause is considered a contraindication (CDC, 2014).
Rotavirus vaccination is contraindicated for children with a previous history of intussusception or severe combined immunodeficiency (SCID) (CDC, 2014).
Vaccinations that contain weakened live viruses, such as MMR, varicella, and LAIV, are contraindicated in immunosuppressed patients. Examples would be patients receiving chemotherapy or those with advanced HIV disease. These vaccinations should also not be given to pregnant women (CDC, 2014). The ACIP also advises against LAIV in children who have asthma or chronic medical conditions such as diabetes or kidney disease (CDC, 2014).