Are You Sick?

Fever

Is this your symptom?

Fever is the only symptom
An abnormal high body temperature

Causes of Fever

Infection

Most fevers are caused by a new infection. Viruses cause 10 times more infections than bacteria. The number of germs that cause an infection are in the hundreds. Only a few common ones will be listed.
Viral Infections. Colds, flu and other viral infections are the most common cause. Fever may be the only symptom for the first 24 hours. The start of other viral symptoms (runny nose, cough, loose stools) is often delayed. Viral infections can range from mild (goes away on its own after a day or two) to serious and sometimes life threatening. Antibiotics are not helpful for viral infections. They will not kill viruses.
Bacterial Infections.
- Common bacterial infections include:
- Bacterial infections can occur on their own or can follow a viral infection. If a fever has not gone away within 3 days, it could be that there is a bacterial infection. Your doctor may want to take some tests before ordering antibiotics, such as a urine test or throat swab. Like viral infections, bacterial infections can be mild or can also be serious and life threatening. Seek care if your condition is worsening or not getting better within 72 hours.
Travel to high-risk areas. If you have travelled to a different region or country and developed a fever, it is important to contact your doctor. Infections from other areas can cause fever and may be serious and require specific medicines. These include malaria, tuberculosis, hepatitis A and B and Lyme disease.

Other Causes of Fever

Blood clots (serious). These can occur in the legs (deep vein thrombosis) or in the lung (pulmonary embolism) and may present with fever. You may have swelling and/or pain in your legs, chest pain or difficulty breathing along with the fever.
Inflammatory conditions. There are many conditions which cause inflammation in the body and a rise in temperature. Examples are rheumatoid arthritis and other joint problems.
Immune system disorders. Immune system problems, such as lupus, can cause fever. If you have a weakened immune system, your body will be less able to defend itself against viral or bacterial infections. Contact your doctor if you get a fever. Examples of a weakened immune system include sickle cell disease, HIV, cancer, organ transplant, taking oral steroids, diabetes, kidney problems.
Heat exhaustion. Long exposure to high temperatures indoors or outdoors can cause a rise in body temperature. It is worse if you’re doing strenuous activity and not keeping well hydrated.
Immunizations. Fever may follow some immunizations such as diphtheria, tetanus, pertussis or pneumococcal vaccine.
Medicines. Some meds, such as antibiotics and those that treat high blood pressure or seizures, can cause fever.
Cancer. Some types of malignant cancer can cause fever.

Normal Temperature Range

Rectal. A reading of 98.6° F (37° C) is just the average rectal temp. A normal low can be 96.8° F (36° C) in the morning. It can change to a high of 100.3° F (37.9° C) late in the day. This is a normal range.
By mouth. A reading of 97.6° F (36.5° C) is just the average mouth temp. A normal low can be 95.8° F (35.5° C) in the morning. It can change to a high of 99.9° F (37.7° C) late in the day. This is a normal range.

When to Call for Fever

When to Call for Fever
Call 911 Now Not moving or too weak to stand Can't wake up Severe trouble breathing (struggling for each breath, can barely speak) Purple or blood-colored spots or dots on skin You think you have a life-threatening emergency Call Doctor or Seek Care Now You have other symptoms with your fever such as breathing problems, abdominal or back pain, urinary symptoms Recently had surgery Recently had a baby Measured fever over 103° F (39.4° C) or seems like a very high fever (feels very hot to touch) Shaking chills (shivering) You feel dehydrated (dark urine, very dry mouth, dizzy when standing) Weak immune system. Examples are: sickle cell disease, HIV, cancer, organ transplant, taking oral steroids, diabetes, kidney problems. You feel very sick You think you need to be seen, and the problem is urgent	Contact Doctor Within 24 Hours Fever lasts more than 3 days Fever returns after being gone more than 24 hours Recent travel outside the country to high risk area You think you need to be seen, but the problem is not urgent Contact Doctor During Office Hours You have other questions or concerns	Self Care at Home Fever with no other symptoms and you feel only mildly ill

Call 911 Now

Not moving or too weak to stand
Can't wake up
Severe trouble breathing (struggling for each breath, can barely speak)
Purple or blood-colored spots or dots on skin
You think you have a life-threatening emergency

Call Doctor or Seek Care Now

You have other symptoms with your fever such as breathing problems, abdominal or back pain, urinary symptoms
Recently had surgery
Recently had a baby
Measured fever over 103° F (39.4° C) or seems like a very high fever (feels very hot to touch)
Shaking chills (shivering)
You feel dehydrated (dark urine, very dry mouth, dizzy when standing)
Weak immune system. Examples are: sickle cell disease, HIV, cancer, organ transplant, taking oral steroids, diabetes, kidney problems.
You feel very sick
You think you need to be seen, and the problem is urgent

Contact Doctor Within 24 Hours

Fever lasts more than 3 days
Fever returns after being gone more than 24 hours
Recent travel outside the country to high risk area
You think you need to be seen, but the problem is not urgent

Contact Doctor During Office Hours

You have other questions or concerns

Self Care at Home

Fever with no other symptoms and you feel only mildly ill

Care Advice for Fever

What You Should Know about Fever:
- Your body temperature varies throughout the day and from day to day.
- A fever is a rise in the body temperature above the body’s normal range.
- Having a fever is a sign that a change is going on in your body. It is most often a new infection and is most likely caused by a virus.
- You may not know the cause of the fever until other symptoms develop. This may take 24 hours or more.
- Most fevers are helpful. They help the body fight infection. Viruses don’t survive well if the body is too hot.
- Fevers often go away on their and don’t need treatment.
- You may feel shivery when you have a fever, Shivering causes the body temperature to rise. It is a sign the body is fighting the infection. In rare cases, you may find you are shaking (rigors). If you have rigors you should call your doctor for advice.
- Other symptoms often felt with fever include sweating, headache, muscle aches, loss of appetite, feeling irritable, weakness and dehydration.
- Here is some care advice that should help.
Avoiding Infection
- Reducing exposure to infection is the best way to avoid a fever.
- Wash your hands often especially before eating and using the toilet. Wash hands after spending time in a crowd, caring for someone who is sick, petting animals, using the toilet and travelling on public transport. Wash hands after coughing, sneezing or blowing your nose. Throw used tissues away.
- Wash hands thoroughly for 20 seconds with soap and water and rinse under running water.
- Use hand sanitizer if you don’t have access to soap and water.
- Avoid touching your nose, mouth or eyes.
- Cover your mouth when you cough; cover your nose when you sneeze.
- Avoid sharing cups, water bottles and utensils.
- Stay at home when you are sick and avoid close contact with others who are not sick if you can.
- Avoid close contact with others who are sick, if possible.
- Face masks, if worn, should cover the nose and mouth and may help reduce spread of infection.
- Avoid hugging and kissing others.
- Wipe down touched surfaces or objects such as doorknobs, kitchen surfaces and mobile devices.
Vaccines:
- Vaccines can prevent infection or reduce disease severity.
Measuring Your Temperature:
- Thermometers vary in accuracy. It is useful to measure your temperature, but the most important thing is how you feel. If you think you have a fever, then assume you do and take action based on how well or ill you are or appear to be.
- There are many types of thermometers: oral (mouth), rectal, ear (tympanic) and forehead. Oral and rectal thermometers are the most accurate.
- If you do measure your temperature, the ranges below may help you interpret your fever:
Treatment for All Fevers - Extra Fluids
- Fluids alone can help lower the temperature and also help you feel better. Reason: you lose fluids through your skin when you have a fever (sweating). This helps reduce the fever, but you could become dehydrated. Drink plenty of fluids to prevent dehydration.
Fever Medicine:
- A fever only needs to be treated with medicine if it is making you feel ill. Most often, that means a fever above 102° F (39° C). Also use for shivering (shaking chills). Shivering will cause the temperature to increase further.
- For fevers higher than 102° F (39° C), take an acetaminophen product (such as Tylenol).
- Another choice is an ibuprofen product (such as Advil).
- Use as needed but do not take more than the maximum recommended dosage as stated on the package.
- If you are not sure what to take, ask a pharmacist.
- Goal of treatment: bring the temperature down to a level where you feel comfortable. Most often, the fever meds lower the fever by 2° to 3° F (1 - 1.5° C). They do not bring it down to normal. It takes 1 or 2 hours to see the effect.
Sponging with Lukewarm Water:
- Note: sponging is an option for high fevers. It might help you feel better.
- When to Use: fever above 104° F (40° C) that doesn't come down with fever meds. Always give the fever medicine at least an hour to work before sponging.
- How to Sponge: use lukewarm water (85 - 90° F or 29.4 - 32.2° C). Sponge for 20-30 minutes. Using water that is too cold will feel uncomfortable and cause more shivering, making the temperature up higher. The goal is to dampen the skin and the evaporation of the water from the skin will help cool you down.
- If you shiver or becomes cold, stop sponging or make the water warmer.
Other Tips:
- Rest until your fever has come down.
- Avoid strenuous activity.
- If shivering, put on an extra layer of clothes which you can easily remove if you start to overheat.
- In bed, rest under a light sheet rather than a heavy blanket which may send your temperature up further.
Return to Work and Other Activities:
- You can return to work and other activities after the fever is gone. You should feel well enough to join in normal activities.
What to Expect:
- Most fevers with viral illnesses range between 101° and 104° F (38.4° and 40° C).
- They may last for 2 or 3 days.
- They are not harmful.
Call Your Doctor If:
- You feel very sick
- Any serious symptoms occur such as trouble breathing
- Fever goes above 104° F (40° C)
- Fever lasts more than 3 days (72 hours)
- You think you need to be seen
- Your symptoms get worse

And remember, contact your doctor if you develop any of the 'Call Your Doctor' symptoms.

Disclaimer: this health information is for educational purposes only. You, the reader, assume full responsibility for how you choose to use it.

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