Pierce County, Washington. Pierce County is a county in the U.S. state of Washington. As of the 2010 Census, the population was 795,225, making it the second-most populous county in Washington behind King County. The county seat and largest city is Tacoma.
You can be contagious from a few days up to two weeks or more, depending on which virus is causing your stomach flu (gastroenteritis). A number of viruses can cause gastroenteritis, including noroviruses and rotaviruses.
The flu is contagious a day before and five days to a week after its onset. Young children, people over 65, those with compromised immune systems, and people with a terminal illness are at risk of death from the flu. Pregnant women are also at greater risk.