Symptoms of Influenza

Symptoms of Influenza
The influenza virus usually enters the body through the respiratory tract but can also gain access through the intestinal tract. The virus causes a variety of symptoms with fever, sore throat, cough, runny nose and general aches and pains as the leading ones. In addition to these principal symptoms many also experience headache, nausea, abdominal cramps and diarrhea.
These symptoms could be due to some other infectious agent or even the influenza virus but not the pandemic strain since it is possible that both endemic (routine seasonal flu varieties) and pandemic strains could both be circulating in the community at the same time if the pandemic flu appeared during the November-March flu season. In fact, this scenario is what looks to be the most likely time for the pandemic to begin. The best guess for the start of the pandemic at this point is between December 2005 and April 2006.
There are several ways to tell the difference between the flu and less severe illnesses. First of all, unless the flu is circulating in the community, then your illness is probably not flu, because it tends to occur in epidemics that are easy to spot epidemiologically. If the world is in the midst of a major pandemic, you will have no problem knowing about it. Just tune into CNN, as it is likely to be wall-to-wall pandemic coverage 24/7. Another clue to whether or not someone has flu is that flu is much worse than simple cold viruses or most other causes of respiratory or gastrointestinal (GI) infections. The fever and body aches are really quite remarkable and often associated with strong shivering.
When flu affects the GI tract it presents with nausea, vomiting and diarrhea. Patients with flu are really sick and often are so weak they have a hard time getting up out of bed without help. So, one way to tell the difference between the flu and other infections is that the flu is really severe and tends to affect the respiratory track most often, but can also cause severe gastroenteritis (nausea, vomiting, and diarrhea).