US Medical Term · symptoms
Fever
Fiebre
In 9 languages
| Language | Term |
|---|---|
| English | Fever |
| Spanish (Español) | Fiebre |
| Chinese (中文) | 發燒 |
| Korean (한국어) | 발열 |
| Vietnamese (Tiếng Việt) | Sốt |
| Filipino (Tagalog) | Lagnat |
| Portuguese (Português) | Febre |
| Thai (ภาษาไทย) | ไข้ |
| Japanese (日本語) | 発熱 |
What it means
Fever is a rise in body temperature above 100.4°F (38°C). It is usually a sign that your immune system is fighting an infection, such as the flu, a cold, or a bacterial illness. Other causes include inflammation, certain medications, or heat exposure. Mild fevers often resolve with rest and fluids. Seek care if your temperature exceeds 103°F, if the fever lasts more than three days, or if it is accompanied by severe headache, rash, stiff neck, or difficulty breathing. Infants under three months with any fever need immediate medical attention.
How to say it
Sentences a patient might use with a doctor, nurse, pharmacist, or insurer:
I have had a fever for the past two days.
He tenido fiebre durante los últimos dos días.
My temperature reached 102°F last night.
Mi temperatura llegó a 102°F anoche.
I feel hot and chills keep coming and going.
Me siento con calor y tengo escalofríos que van y vienen.
Where you'll see it
Related ICD-10-CM category
R50 Fever of other and unknown originRelated terms
Sources
Last reviewed: September 2026