Pharmacy Corner
Fever in Children: Sorting Facts From Myths Fever and its Causes


What is a fever?

Fever is a body temperature that is 38°C or higher.1 Fever happens when the brain’s thermostat dials up the body’s normal temperature after it senses the body is sick from an infection or another type of illness.1,2,5


MYTH: Fever is an illness.

Fever is not an illness but a sign of illness, and a good sign to boot. Why?1,2

  • Fever is one of the body’s natural defenses against illness by helping the immune system work faster to kill bacteria and viruses.

  • Fever lets you know that your child is unwell and that his or her body is fighting the infection.


What causes fever in infants and children?

Some causes of fever in infants and children are:3

  • Infections: Infections are the most common causes of fever in children. If your child ever gets a cold, the flu, a stomach bug, or ear infection, he or she will probably get a fever.
  • Vaccines: A fever can happen up to two weeks after your child gets a vaccine, depending on the specific vaccine. This is normal and just means that your child’s immune system is building up protection against the vaccine.


MYTH: Dressing a newborn in too many layers can cause fever.

Bundling newborns less than 3 months of age can make them overheat since newborns cannot regulate their temperatures as well as older children.5 But temperatures above 38.5°C (101°F) are not likely to be caused by overdressing and should be checked by a doctor.3,4


MYTH: Teething causes fever.

Sometimes a child’s temperature will spike just before and during the time the tooth breaks through the gums.6 However, a high or persistent fever during teething is not normal. Signs that your child may be ill for a reason unrelated to teething include:6

  • A temperature that is higher than 38.9°C (102°F)

  • A fever that lasts for more than one day before and after the tooth appears