Anyone who has been felled by nausea and diarrhea lately is not alone.

March through May is high season for the highly contagious norovirus in Pima County.

The illness is often misidentified as "stomach flu" and typically lasts 24 to 48 hours. In rare cases it can be life-threatening. Since it's so contagious it can cause outbreaks in places where large groups of people live or congregate such as long-term care facilities, schools and social gatherings.

Norovirus are actually a group of viruses that are the most common cause of gastroenteritis in the U.S. Gastroenteritis means inflammation of the stomach and intestines.

Typical symptoms include nausea, throwing up, diarrhea and stomach cramps. Occasionally, people will also experience mild fever, chills, headache, body aches and feel very tired.

The illness can be easily spread to other people through direct contact and contact with contaminated surfaces.

Children usually throw up more often than adults.

While unpleasant, the illness typically doesn’t last long. For most people, symptoms last 24 to 48 hours with no long-term health effects.

However, it can be more severe among the very young, the elderly and people with weakened immune systems. More severe forms of the illness are generally related to dehydration.

State health officials advise washing hands regularly for prevention.

Patients should seek medical attention if they notice blood in their stool; are running a high fever; if symptoms last more than three days; if they feel dizzy or faint more often than usual; if they cannot keep any fluids down due to vomiting; and if they have muscle cramping in legs and arms.