Acute Febrile Illness: Symptoms & Treatment

An error occurred trying to load this video.

Try refreshing the page, or contact customer support.

Coming up next: Squamous Cell Carcinoma: Definition, Symptoms & Treatment

You're on a roll. Keep up the good work!

Take Quiz Watch Next Lesson
Your next lesson will play in 10 seconds
  • 0:02 What Is Acute Febrile Illness?
  • 0:31 Causes
  • 1:16 Symptoms
  • 2:02 Treating Acute Fibrile Illness
  • 3:04 Lesson Summary
Save Save Save

Want to watch this again later?

Log in or sign up to add this lesson to a Custom Course.

Log in or Sign up

Speed Speed

Recommended Lessons and Courses for You

Lesson Transcript
Instructor: Danielle Haak

Danielle has a PhD in Natural Resource Sciences and a MSc in Biological Sciences

Acute febrile illness is the medical term used to describe a sudden fever or elevation in body temperature. This happens when the body is invaded by a pathogen and the immune system is activated to fight it off. In this lesson, learn about the symptoms and treatment options.

What Is Acute Febrile Illness?

When the body is invaded by a foreign pathogen like a virus or bacteria, the immune system kicks into gear and tries to fight the infection before it has a chance to spread. When this happens, the body's temperature is elevated to try to kill off the pathogen, and this results in what we call a fever. Acute febrile illness is when a fever develops suddenly; specifically, the body temperature rises above 37.5 degrees Celsius (99.5 degrees Fahrenheit).


If you've ever been sick, you've probably experienced having a fever, and you know how hard it can be to determine the underlying cause. Acute febrile illness can occur whenever the body is invaded by some type of infectious disease, but it is especially worrisome in tropical and sub-tropical regions where serious diseases loom. These can include malaria, dengue, typhoid, chikungunya, Leptospirosis, scrub typhus, influenza, encephalitis, histoplasmosis, enteric fever, rickettsiosis, Hantavirus, and many, many others. Specifically, the hypothalamus is the part of the brain responsible for regulating body temperature, and it may decide to elevate body temperature in response to an infection.


In addition to causing elevated body temperature, acute febrile illness can be accompanied by headaches, dizziness, sweats, chills, muscle pain, joint pain, and weakness. Sometimes it's also affiliated with respiratory symptoms like coughing or wheezing. A fever in itself isn't necessarily cause for alarm; however, it becomes problematic when the body temperature gets too high or lasts for an extended amount of time.

In infants or very young children, fever may be accompanied by seizures (called febrile seizures). These are generally harmless (although they can be very scary to witness), though it's recommended to take children to the doctor the first time they experience a febrile seizure. They can be recurring, so it's best to make sure they aren't indicative of a more serious cause.

To unlock this lesson you must be a Member.
Create your account

Register to view this lesson

Are you a student or a teacher?

Unlock Your Education

See for yourself why 30 million people use

Become a member and start learning now.
Become a Member  Back
What teachers are saying about
Try it risk-free for 30 days

Earning College Credit

Did you know… We have over 200 college courses that prepare you to earn credit by exam that is accepted by over 1,500 colleges and universities. You can test out of the first two years of college and save thousands off your degree. Anyone can earn credit-by-exam regardless of age or education level.

To learn more, visit our Earning Credit Page

Transferring credit to the school of your choice

Not sure what college you want to attend yet? has thousands of articles about every imaginable degree, area of study and career path that can help you find the school that's right for you.

Create an account to start this course today
Try it risk-free for 30 days!
Create an account