A man from Hemet and a girl from Perris have died after testing positive for influenza, public health officials announced Friday.
Both deaths occurred earlier this month, though exact dates were not provided.
According to Dr. Cameron Kaiser, interim public health officer for Riverside County, the 22-year-old man tested positive for Influenza A, and was briefly hospitalized.
The girl-- just four-years-old-- tested positive for Influenza B, and died after being taken to an emergency room, the doctor said.
Though both did have the flu, Riverside County health officials are saying the cause of death has not been determined.
"Officials do not know how long it will take to determine whether the influenza contributed to the deaths in any way," the department said. "Riverside County has seen some recent increases in instances of influenza-like illness in the region but the overall flu activity is within the normal range."
"Because they tested positive for the flu, we have to report [the deaths] to the state," Barbara Cole, Director for Disease Control for the County of Riverside Department of Public Health, told Patch in a telephone interview.
There have been five similar deaths of people under the age of 65 reported in California this flu season, but Cole didn't know if these two deaths are included that tally yet.
Cole said one person tested positive for the flu and died in the 2012 flu season, however it was not listed as their cause of death.
More information on flu cases reported in Riverside County can be found on the health department's website here.
Cole and county health officials stressed the importance of getting a flu shot this season. The Centers for Disease Control and Prevention (CDC) has recommended that everyone 6 months old and older receive a flu vaccination each year.