Tehama County has seen a big jump in Covid cases. There were 34 reported in the first two weeks of July and 76 in the last two weeks. None of the patients were vaccinated and four of them are carrying the more lethal and contagious Delta variant. Public health officials say each new infection gives the virus the opportunity to mutate into something worse. Tehama County’s vaccination rate is 38%. In Shasta County it’s 41%. Statewide it’s 53% and it’s 50% nationally.