Sonoma County's current case rate is fluctuating between five and six cases per 100,0000 residents, increasing from four on June 15. And Health Officer Dr. Sundari Mase says unvaccinated, young people make up the majority of new cases.

"Yes I'm concerned because we are seeing an increase in cases," Mase said. "Are we at a peak? I'm not sure yet, especially because we just had the fourth of July long weekend."

The rise in COVID hospitalizations also continue, with 44 COVID patients in the hospital and 13 in the ICU, numbers the county hasn't seen since February. But 100 percent of the patients in the ICU and 92 percent of COVID patients in the hospital are unvaccinated. Mase said the highly transmissible delta variant is likely playing a role. 

"There's also the delta variant which is far more transmissible than the prior COVID strains," Mase said. "So that may explain why there's been a burst of cases among unvaccinated groups."

And testing is especially important with the rising cases and circulating delta variant. This week the county started using BinaxNOW rapid antigen tests at its sites.  Employers and clinics have used these tests throughout the pandemic, to get preliminary results faster, especially in symptomatic individual. And Mase said the rapid tests are a good way to get people in isolation quickly while they are awaiting the reliable PCR test.

"The advantage of the Binex now is it's rapid, you can get an answer within 15 minutes," Mase said. "And it's a very simple procedure, it's a swab that doesn't go as far back. And almost like a pregnancy test, it will tell you your result right away."

As cases rise, officials echo the same advice.

"Everyone go out there and get vaccinated and take extra precautions if you're either not vaccinated or between you're two doses," Mase said.