Lowering Baby And Infant Fever After Vaccines And Immunizations
Lowering the temperature of a fever after a vaccination can be confusing for new parents. It is already difficult for new parents to understand immunization schedules and vaccine recalls so seeking help after the vaccine and knowing the right time to ask for help can be an added stress.
I am not a health care professional and I am not licensed to give advise but these are some ways that I have witnessed parents successfully relieving the fever of a young child or infant baby. All of the information on this site and page is based on my opinions as well as feedback from other users. Pediatricians that I have spoken with have mentioned that a higher than normal temperature is part of the child’s process of responding to the vaccine however they still offer ways to lower the fever back to a normal level.
Taking An Accurate Temperature
When taking the temperature of a baby or small child many believe that the most accurate way is by a digital rectal thermometer that is designed for babies by only allowing only about a 1/2 inch to an inch of thermometer to be inserted. I also believe that testing 3 times to confirm the accuracy of the devise is helpful when recording a temperature.
For this example I will consider the normal temperature to be:
98.6 °F or between 96–99 °F
In this case I will consider a fever to be over:
100.4 °F or over 100-101 °F
Medium grade fevers between:
101-102.5 °F
High fevers are normally considered to be around:
102.5-105 °F
Brain damage, which seems to be uncommon from vaccinations, will be considered for fevers over:
107.6 °F (42 °C)
When Should We Call The Pediatrician?
Pediatricians seem to have a different opinions on when to call and how high the temperature should be before there is a concern. Many pediatricians seem to consistently say that if they have not had a recent vaccination and/or if they are under 3 months old (some professionals will say 6 weeks or younger) it would be important to call them right away (day or night) if they are showing above 100.4 °F because this may be a sign of a problem that needs urgent medical attention.
Remember that fever alone is not normally harmful and it actually is helpful as part of the baby’s immune system.
If the child has had vaccinations in the last 48 hours, many professionals will say that it is normal to run a low fever and it not necessary to call them urgently unless the temperature goes above 103 °F medium grade fever however they will normally make recommendations in advance on ways to lower the temperature. I have found that many professionals claim that a fever above 103 °F may be a sign of a potentially dangerous infection.
Why Should We Lower The Baby’s Fever?
Since the baby uses the fever as a way to fight off infection it may seem counterproductive to lower it. Even so, some reasons to lower a fever may be to comfort the child or prevent the additional loss of supplemental fluids caused by the persistent fever (dehydration). Some people have said they try to keep the temperature of the baby as close to a normal level as possible to reduce the risk of febrile seizures which might be caused by a quick change in temperature resulting in a fever.
Reasons including comfort and fluid loss are mentioned on this United States Army site:
http://evans.amedd.army.mil/peds/fever.htm
Common Ways To Lower A Fever
If you do want to lower a fever these are some ways that we have had success with. Again, I am not a medical professional so please consult your advisors and pediatrician before providing any treatment.
1) Consider giving the baby a normal dose of generic brand acetaminophen designed for babies and infants. Be careful however because acetaminophen, such as Tylenol similar drugs, can add to liver damage and Cirrhosis (https://health.google.com/health/ref/Cirrhosis). Normally your doctor will also provide a chart that shows how much to give the baby according to the weight. Also, The Children’s Hospital at 13123 East 16th Avenue Aurora, CO 80045 also mentions, “Caution: Do NOT give your baby any fever medicine before being seen.”
http://www.thechildrenshospital.org/wellness/at_home/baby/illnesses.aspx
2) Feed the baby to help with hydration, immune system nutrients, and to help comfort the baby. You may find that feeding the baby may help to reduce the fever because the baby has the hydration it needs to regulate their temperature easier. Most professionals that I have listened to have advised beast feeding more often during times of fever. Breast milk may also contain anti-inflammatory nutrients that could reduce the risk of a high fever.
3) Use a medium cool compress to reduce the fever heat. This could be done by pouring cool room temperature water on a towel and using it as a compress.
4) Give the baby a room temperature bath. You could even do this with the baby but professionals have mentioned that it is important to use water that is not too cold so that the baby’s temperature does not cool to rapidly or too much.
5) Allow for easy air flow near the baby and consider taking the baby outside if the climate permits. Fresh air is important and helpful for all humans but it may also help lower the average room temperature slightly which may in turn help with the fever. Taking the baby outside could provide fresh air and a cooler climate helping the baby recover from the fever more easily. If you are in a car, be sure to open the windows on a hot day or provide a cool comfortable environment as soon as possible to comfort the baby.
6) Remove excess clothing, blankets, or swaddle attire. There are a few cases I have found where a child has been known to have a much higher fever when over wrapped with blankets and clothing. Removing these extra layers may be enough to help comfort the baby and reduce the temperature back to a normal level.
Concerned About Infant Brain Damage After Immunizations?
Most professionals that I have spoken with are not very concerned about brain damage after immunizations because only around 10% of cases can reach over 103 °F. Even fewer go above the brain damage temperature of 107.6 °F (42 °C). This temperature for brain damage is also published by:
U.S. National Library of Medicine at 8600 Rockville Pike, Bethesda, MD 20894
“Brain damage from a fever generally will not occur unless the fever is over 107.6 °F”
What Are The Chances Of Fever?
It may be said that you have less than a 20% chance of your child developing a fever after their vaccinations. Seattle Children’s Hospital, Research and Foundation at 4800 Sand Point Way NE Seattle WA 98105 has made an informative sheet on this located here:
http://www.seattlechildrens.org/medical-conditions/symptom-index/immunization-reactions/
Specific Immunization Reactions
- Chickenpox Vaccine:
- Pain or swelling at the injection site for 1 to 2 days (in 19% of children)
- Mild fever lasting 1 to 3 days begins 17 to 28 days after the vaccine (in 14%). Give acetaminophen or ibuprofen for fever over 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.
- 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.
- A large swelling over 4 inches (10 cm) arm can follow the 4th or 5th dose of DTaP occurs in 5% of children. Most children can still move the leg or arm normally.
- The large thigh or upper arm swelling resolves without treatment by day 3 (60%) to day 7 (90%). This is not an allergy and future DTaP vaccines can be given.
- Hemophilus Influenza 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 under 2 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.
- Mild fever under 103° F (39.5° C) occurs in 18% of children. Fevers mainly occur in young children.
- Nasal Influenza Vaccine: No side effects, no fever or symptoms.
- 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.
- Mild fever under 103° F (39.5°C) in 10% 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 over 3 days
- Meningococcal Vaccine:
- No serious reactions
- Sore injection site for 1 to 2 days occurs in 50%, with limited use of the arm in 15%.
- Mild fever occurs in 4%, headache in 40% and joint pain in 20%
- The vaccine never causes meningitis.
- Mumps or Rubella Vaccine: There are no reactions except for an occasional sore injection site.
- Pneumococcus Vaccine:
- No serious reactions
- Pain, tenderness, swelling OR redness at the injection site in 15 – 30%
- Mild fever under 102° F (39° C) in 15% for 1-2 days
- Polio Vaccine:
- Polio vaccine by injection occasionally causes some muscle soreness.
- Oral vaccine no longer used in the U.S.
- Rotavirus Vaccine:
- No serious reactions to this oral vaccine
- Mild diarrhea or vomiting for 1 to 2 days in 3%
- No fever
- Human Papillomavirus Vaccine:
- No serious reactions reported
- Sore injection site for few days in 80%
- Mild redness and swelling at the injection site (in 25%)
- Fever over 100.4° F (38.0° C) in 10% and fever over 102° F (39° C) in 1-2%.
You can also report fevers and any adverse reactions to the FDA’s VAERS site at https://vaers.hhs.gov/esub/step1. VAERS seems to be used for taking information and will not provide any help with understanding when to call your doctor or take your baby to the emergency room due to an adverse reaction. They do however provide some excellent data from vaccinations that you can sort in a variety of ways including by state and by symptom. You can download the data for any recent year here: https://vaers.hhs.gov/data/data/
This seems to be a easy to understand video about fevers:
I hope this information can help you or a baby’s life that you know. If you have any other questions or comments about baby fevers after vaccinations please feel free to leave you comment or message on this site. A friend also noted that you should only take your child to the ER or doctor if it is needed because exposure to pollution/dangers during the drive, exposure to illness at the location, and other complications could hurt the baby more than the natural reaction of the fever.

