Swine Flu Symptoms, Diagnosis, and Vaccination

Medical Author: Benjamin C. Wedro, MD, FAAEM
Medical Editor: Melissa Conrad Stöppler, MD

The pressure to manufacture and distribute the H1N1 vaccine before the H1N1 (swine) influenza virus begins its autumn spread is ongoing, but so far it seems that the virus may be winning. The race, though, is far from over, but in more than 40 states, the number of people being diagnosed clinically with the "swine" flu is growing.

"Clinically" is the key word, since testing for the influenza virus is no longer recommended. Instead, health care practitioners are using history as the guide to whether H1N1 is the likely diagnosis. The most frequent symptoms are fever, cough, shortness of breath, and fatigue. These are pretty non-specific complaints, but in today's setting of widespread influenza it is enough to be relatively certain that influenza is the cause? Less commonly, there may be chills, muscle aches, runny nose, sore throat, and headache. Interestingly, H1N1 also may present with vomiting and diarrhea, two symptoms that tend not to be associated with the usual influenza pattern.