When your body temperature is higher than it should be (usually 98.6 F), it's called a fever — and having one is a sure clue that your body is defending itself from an infection or illness. It’s a typical symptom of influenza, along with a stuffy and runny nose, fatigue, aching (everywhere), and headaches.
Not everyone with a flu will develop a fever, though — research shows that somewhere between 40 and 66 percent of adults, and something like 89 percent of children with the flu, will. The odds depend on the strain — fever is more common with A than B strains.
If you are an adult a fever is annoying but unlikely to pose a serious risk. Do get in touch with your doctor if your temperature reaches 103 F (39.4 C) or even higher. Always take children younger than three months old should to a doctor if their temperature is 100.4 F (38 c) or higher, and the same goes for older children who have a temperature of 102 F (38.9 C) or above.
How do I take my temperature?
If you don't have a thermometer yet, go out and get one — it'll always come in handy, and stop you from wondering whether or not you have a fever. Once you're set, it's also important to know how to take your temperature.
- Take the thermometer, put in in your armpit, and then cross your arms over your chest. Keep it in place for four or five minutes. Your axillary (armpit) temperature won’t be quite as hot as your oral temperature — so let your doctor know how you took your temperature as well.
- If you have an infant, you should use a rectal thermometer. Put a bit of petroleum jelly on the bulb, turn your baby onto their stomach, and place the bulb inside your infant’s rectum (uo to 2.5 cm deep). Hold your infant and the bulb in place for three minutes.
Taking care of your feverish child
The American Academy of Pediatrics recommends that you:
- Focus your efforts on helping your child feel more comfortable and helping them get better sooner.
- Be careful with over the counter pain relievers and fever reducers. Don’t wake your sleeping child up to give them the next dose, the AAP suggests, and if you do give fever reducers like acetaminophen (Tylenol) or ibuprofen, be very sure the dosage is correct for your child’s age and weight. There is some evidence that alternating ibuprofen and Tylenol is more effective, but beware that this also increases the risk that you’ll get the dosing wrong.
Parents who do choose to use an over-the-counter fever reducer should know that:
- You can’t give a baby younger than two months old paracetamol.
- Ibuprofen, on the other hand, can be given to a baby over three months old who weights more than 11lbs (5kg).
- Never give Aspirin to any child, since it comes with the small but real risk of Reye’s syndrome — a potentially deadly condition.
There are a lot of other ways to make your child feel better, as well. Sit with them and allow them to stay in bed or set them up in the living room on a comfy couch. Don't use too many blankets, which could potentially lead to overheating, and offer light foods like broths and fruit, but don't worry if your child doesn't have much of an appetite. Do make sure your child drinks lots of water, or breastfeed nursing babies as much as they want. You should keep your eye open for any indications your child is dehydrated, which include:
- Sunken eyes
- A dry mouth
- Your baby doesn’t have as many wet diapers or your child doesn't go to the bathroom very often
- No tears
How to treat a fever in adults
Most adults can safely use over the counter pain relievers and fever reducers, which will fight flu-related aches and pains while bringing your temperature down at the same time.
- Taking 400 mg of ibuprofen can help you feel a little better in only half an hour. The maximum dosage you can take is 1200 mg every 24 hours. Wait for four to six hours to take another dose.
- Acetaminophen (Tylenol, paracetamol) takes up to one hour to begin working, you and you can take 500 mg or 1000 mg — two tablets — to reduce your fever. You can’t take more than eight 500 mg tablets every 24 hours and again, wait at least four hours before taking another dose.
Adults, too, have to make sure they're getting enough fluids — not just to keep dehydration at bay but also to help you expel mucus, something expectorants and steaming can also assist you with. Get plenty of rest, and get someone else to look after you a bit.
The flu and fever: When is it time to call a doctor?
You should go to the ER when you think your child has the flu and you see one or more of these symptoms:
- You notice your child is breathing fast or they’re having difficulties breathing
- They have a somewhat blue skin color
- They aren’t drinking enough water
- They have a fever with a rash
- Your child is really irritable and they don’t want to be held
- They have flu symptoms that become better but come back with a bad cough and a fever
Adults with the flu should rush to the ER if they experience dizziness, confusion, intense or constant vomiting, chest pains, or swelling in the throat or mouth. Also, go to the ER if you have flu-like symptoms which become better but then return with a bad cough and a fever.