What are the symptoms of influenza (the flu)?
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Symptoms of Influenza (The Flu)
Common Symptoms of Influenza
Influenza, commonly known as the flu, is an infectious disease caused by the influenza virus. The symptoms of influenza can range from mild to severe and often appear suddenly. The most common symptoms include high fever, runny nose, sore throat, muscle pains, headache, coughing, sneezing, and a general feeling of tiredness . These symptoms are typically more intense than those of the common cold and can significantly impact daily activities.
Respiratory Symptoms
Respiratory symptoms are a hallmark of influenza. These include a dry cough, sore throat, runny or stuffy nose, and sneezing . In some cases, individuals may experience watery eyes and sinus pain. The virus primarily affects the respiratory tract, which can lead to complications such as pneumonia, especially in vulnerable populations like the elderly, infants, and those with pre-existing health conditions .
Systemic Symptoms
Systemic symptoms of influenza include high fever, which can range from 100°F to 104°F and may reach up to 106°F in severe cases. Fever is often accompanied by chills and shaking. Other systemic symptoms include severe muscle aches and pains, commonly in the back, arms, or legs, as well as headaches and fatigue . These symptoms can lead to a general feeling of malaise and loss of appetite.
Gastrointestinal Symptoms
While less common, some individuals, particularly children, may experience gastrointestinal symptoms such as vomiting and diarrhea. These symptoms are not as prevalent as respiratory and systemic symptoms but can still occur in certain cases.
Duration and Severity
The severity and duration of influenza symptoms can vary. Systemic symptoms like fever and muscle aches tend to peak within the first two days and may resolve faster than respiratory symptoms, which can persist for up to two weeks. The overall symptom burden is usually highest during the first four days of illness.
Conclusion
Influenza presents with a range of symptoms that primarily affect the respiratory system but can also include systemic and gastrointestinal manifestations. High fever, cough, sore throat, muscle aches, and fatigue are the most common symptoms. Understanding these symptoms can aid in early diagnosis and treatment, helping to mitigate the impact of this highly contagious virus.
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