Fever in Infants

Fever is very common in children under 12 months of age, and is usually a sign that the body is fighting an infection. The normal body temperature is 98.6F, or 37C. Doctors generally say that there is a fever when the temperature is 100.4F (38C) or higher. The best way to take an infant's temperature is rectally with a digital thermometer (never use a glass mercury thermometer). Taking the temperature under the arm, or using an ear thermometer, is less exact.
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