The Benton Franklin Health District is investigating several recent suspected norovirus outbreaks that have sickened dozens of people in the Tri-Cities.
Dr. Amy Person, the district's health officer, said the reports have come from work groups, sports teams, families and other groups.
Test results aren't back from the state lab yet, but the symptoms and timing suggest norovirus, Person said.
Noroviruses are a group of highly contagious viruses that can infect the stomach and intestines and cause symptoms such as diarrhea, abdominal cramps, nausea, fever and headaches.
Symptoms usually appear within 24 to 48 hours after exposure and go away within 48 hours. There is no specific treatment or vaccine.
Norovirus illnesses aren't typically fatal unless the person experiences severe dehydration or has other underlying medical conditions, Person said.
The virus can be spread in a number of ways -- through contact with another person, consuming contaminated food or water, or touching contaminated surfaces such as doorknobs, faucets and sports equipment.
"The best prevention is good handwashing," Person said.
Nothing so far suggests any link between the Tri-City outbreaks.
"We don't see any relationship between the different groups we're getting calls on," Person said. "We're seeing a number of unrelated gastrointestinal illnesses all associated with group gatherings. There's no common food or water source."
Noroviruses often can spread rapidly when large groups of people get together in confined spaces -- such as the illness that swept through the popular Radcon science fiction convention in Pasco and a state cheerleading tournament in Everett in February 2012.
The health district offers these tips for preventing the spread of norovirus:
-- Wash hands with soap and warm water after using the restroom or before preparing or eating food.
-- Stay home from work or school if sick.
-- Don't rely on alcohol-based hand sanitizers, as they're not effective against norovirus.
-- Michelle Dupler: 582-1543; firstname.lastname@example.org; Twitter: @mduplertch