Experts say the Delta variant is spreading twice as fast as others.
Now, health officials are concerned about our hospitals, once again, being overwhelmed by COVID patients.
Mariposa County health officials say they are seeing a significant rise in cases.
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Last Friday through Monday, they recorded 21 cases.
"Our spike here kind of started with travel of community members outside of the area or having friends or family visiting from other areas," said Lizz Darcy with Mariposa County Health and Human Services.
Darcy said the last big spike the county saw was around New Year's Eve.
Since they started tracking breakthrough cases in vaccinated individuals around June, health officials say they've seen 22 vaccinated people test positive of the 115 total cases.
Darcy said they are also seeing positive cases in children on the rise.
Sher said most of those children were exposed to the virus by someone else in their home.
"Whatever action you can take to reduce the risk for yourself and your community, we're asking people to do that," said Darcy.
Fresno County Public Health officials said their COVID cases are also dramatically increasing.
"Recently, we've had 261 new cases per day, and just to give you a comparison, in early June, that number was about 20 new cases per day," said Dr. Trinidad Solis with the Fresno County Public Health Department.
Hospitalizations in Fresno County have nearly tripled in the last few weeks, jumping from 60 to 173.
Mariposa and Fresno County Health officials agree the increase is likely due to the highly contagious Delta variant.
While the vaccine doesn't fully protect people from getting infected with the virus, doctors say it's still one of the best forms of protection.
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"Even if it's not stopping you from getting a mild illness, it is stopping you from being hospitalized and dying from it," said Dr. Sukhjit Dhillon, a co-director of the COVID Equity Project at UCSF Fresno.
Health officials say it's unclear if the Delta variant causes more hospitalizations or deaths compared to other variants right now, but they do know it's much more transmissible.
That's why doctors recommend you continue to wear a mask regardless of your vaccination status, don't go to large gatherings and get vaccinated.
"There's so much changing all the time and I think we just have to continue to do our part," said Dr. Dhillon.
Health officials say children under 12 are especially vulnerable right now because they are not eligible to get vaccinated.
They are urging people, as students head back to school, to go back to the basics: wash your hands, wear a mask and distance yourself from others.
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