(AP) -- California public health officials plan to give an update on a virus that has infected at least nine children in the state and has caused hundreds of respiratory illnesses and possibly several deaths nationwide.
The California Department of Public Health plans to give the briefing Friday afternoon on enterovirus D68.
At least three new cases emerged in minors in Northern California on Thursday - two in Alameda County and one in Solano County.
Cases have also been reported in children in Los Angeles, San Diego and Ventura counties.
Enterovirus D68 can cause mild to severe respiratory illness and can attack the nervous system in severe cases. There's no vaccine or specific treatment.
More than 500 cases have been reported in 43 states. Many patients have been children. Four people with the virus have died, although it's unclear what role it played.