Flu
•Last Updated: October 13, 2024
“The flu” is a type of respiratory infection caused by influenza viruses. It has a lot in common with the common cold, but its symptoms tend to come on faster and be more severe. It isn’t typically serious, but it can be severe in newborns, older people, and people with immune issues.
Flu falls under theImmunity & Infectious Diseasecategory.
Last Updated:October 13, 2024
"The flu" refers to respiratory infections caused by constantly changing influenza viruses, which can lead to repeated infections. Although influenza infection is usually not serious for most people, it can pose severe risks to newborns, older adults, and people with weakened immune systems.
The main signs and symptoms of the flu include fever and/or chills, muscle aches, fatigue, cough, sore throat, runny or stuffy nose, and headaches. These symptoms typically appear more rapidly and are more severe compared to those of the common cold.
The flu is often self-diagnosed, and many people do not seek medical treatment. In clinical settings, diagnosis involves taking a patient history and may include testing while also ruling out other similar conditions like COVID-19 and RSV.
The flu vaccine is the best prevention method but does not treat existing infections. Antiviral drugs can reduce the flu's duration and severity if they are taken early on, and nonsteroidal anti-inflammatory drugs and acetaminophen can help manage symptoms.
Vitamin C and vitamin D have moderate evidence for reducing the risk of upper respiratory infections and shortening their duration, but only vitamin D has been specifically shown to lower the risk of contracting the flu.
Diet plays a crucial role in immunity, and adequate energy, micronutrients, and macronutrients help to strengthen the immune system and potentially reduce the risk and severity of flu infections. Additionally, flavonoids — found in foods like tea, chocolate, capers, and oregano — may also contribute positively to immune function.
Basic health hygiene habits, including covering coughs and washing hands, are essential for preventing the spread of the flu.
The flu is caused by influenza viruses, specifically types A and B, which circulate among humans and lead to seasonal increases in flu cases. Influenza A viruses can also infect other animals and may cause pandemics if they transfer to humans.
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