Students at two schools in Santa Rosa have become ill with what health officials suspect is norovirus.
Thirty children at Monroe Elementary School stayed home on Monday, and 10 students at Rincon Valley Middle School became ill last week, Santa Rosa City Schools Superintendent Sharon Liddell said.
The students had stomachaches and low-grade fevers symptomatic of norovirus, which can also cause vomiting and diarrhea. The illness usually lasts a day or two.
No other schools have reported suspected norovirus cases, and neither Monroe Elementary School nor Rincon Valley Middle School has asked for assistance from the Sonoma County Public Health Department, public health director Dr. Mark Netherda said.
"It's not unusual for this time of the year. We're not treating it as an unusual occurrence," he said.
Students and school staff are being advised to wash their hands frequently with soap and water, rather than hand sanitizer, and to stay home for at least 48 hours after symptoms subside, Netherda said.
Both school principals sent letters or emails to parents advising them of the precautions they should take, Liddell said.
School janitors are sanitizing doorknobs and other frequently touched areas at the Monroe school, Liddell said.
If a doctor diagnoses the illness as norovirus, students should stay home a day or two longer, Liddell said.
"This is nothing to be alarmed about," Liddell said.
In January, two senior residential care facilities and a preschool in Marin suffered norovirus outbreaks.
A stomach flu sickened hundreds of students and dozens of teachers at St. Ignatius College Preparatory in San Francisco this week, prompting school officials to shut down the campus until Monday.