Influenza A is a subtype of the viruses responsible for most cases of seasonal flu worldwide. The group includes the strands that produce bird flu and swine flu, two especially debilitating illnesses that are notoriously difficult to treat and can cause widespread epidemics. Common symptoms of influenza A include high fever, chills, fatigue, and head and muscle aches. A person may also experience abdominal pains, nausea, and vomiting if he or she is infected with certain types of the virus. It is important to recognize the key symptoms of influenza A early and seek treatment right away to provide the best chances of a quick recovery.
The symptoms of influenza A usually first start to appear about three days after a person contracts the virus. Fever and body chills tend to worsen over the course of two to three days and gradually get better after about one week. It is common to experience a dry cough, fatigue, joint pain, muscle aches, and a persistent headache as well. Symptoms can become severe enough to make it very difficult to move around the house or even sit up in bed.
Some types of influenza A can cause additional symptoms, including a sore throat, chest pain, and nasal congestion. Many people experience gastrointestinal problems such as stomach upset, diarrhea, and vomiting. Frequent bouts of diarrhea and vomiting can lead to dehydration, which tends to exacerbate a person's existing symptoms of fatigue and muscle aches.
Infants, children, elderly people, and individuals with weak immune systems may experience more severe symptoms of influenza A. Without prompt treatment, it is possible for potentially life-threatening complications to arise. A person may develop acute pneumonia or suffer a collapsed lung, either of which can lead to total respiratory failure. The influenza A virus can also cause underlying health problems such as diabetes and heart disease to worsen, possibly resulting in serious heart problems and blood pressure issues.
A person who experiences relatively mild symptoms of influenza A should try to rest as much as possible and avoid close contact with others. It is important to drink lots of water and other clear fluids to avoid dehydration. Over-the-counter anti-inflammatory drugs such as ibuprofen and aspirin may help relieve aches and bring down high fevers. Medical care at a doctor's office or emergency room is needed if symptoms become severe. A physician may prescribe antivirals or suggest hospitalization to ensure a patient receives proper care.
