Influenza is a seasonal virus, most common in the winter and early spring. While people often refer to seasonal colds as “the flu,” true influenza is a serious illness characterized by a high fever and other characteristic effects. While most people suffering from flu make a full recovery within a few weeks, influenza can be quite dangerous to the very young, the very elderly, and the immunocompromised. The National Institutes of Health note that in sensitive populations, the flu can become very serious very quickly, and can even allow for the infection by opportunistic pathogens such as pneumonia. As such, it’s worthwhile to visit a doctor as soon as symptoms develop.
Fever
Influenza causes a rapid-onset high fever. This symptom, notes the National Institutes of Health (NIH), differentiates it from seasonal colds, which rarely involve fevers of more than a few degrees higher than normal. The Mayo Clinic indicates that true influenza is generally characterized by fevers greater than 101 degrees Fahrenheit in adults, and fevers as high as 105 degrees Fahrenheit in children.
Body Aches
When the immune system begins to fight of a systemic infection, immune cells release inflammatory chemicals. These help to kill invading cells by making the body a hostile environment for the pathogens, but they come with their share of uncomfortable side effects, not the least of which is a generalized achiness in the muscles and joints. The U.S. Centers for Disease Control and Prevention, or CDC, notes that while body aches don’t necessarily indicate that a sick individual has the flu, they’re yet another symptom that assists in making an accurate diagnosis.
Fatigue
Like many viruses and bacteria, flu viruses cause generalized immune responses that can leave a patient feeling run down and weak. It’s best to rest in these cases; while the severity of flu can be lessened by using certain antiviral drugs, antibiotics are not effective. As such, the best way to treat the flu is to treat the symptoms, maximize patient comfort, and assist the immune system in eradicating the virus. Plenty of rest helps ensure that the immune system is able to do its job as quickly as possible.
Headache
Like fever, headache is another hallmark of the flu that is very rare in other seasonal viruses. While stuffy nose, sore throat, a cough, and generalized achiness may be associated with any number of bugs, symptoms that arise quickly, feel quite severe and include headache in addition to fever are likely to be indicative of influenza, note the NIH.
