The Delta variant of Covid-19 continues to dominate in Riverside County but new variants are emerging, including the Lambda variant, which is now in California.
Experts say Lambda could be more infectious and resistant to vaccines than the initial coronavirus strain, but it isn't yet called a "variant of concern" in the U.S. or by the World Health Organization.
Dr. Peter Chin-Hong, an infectious disease specialist at University of California San Francisco, said the Lambda mutation is predominant in South America right now, making up 80 to 90 percent of new cases in Peru – but it's spreading in the Golden State now too.
"The Lambda variant is definitely here, but the Delta variant is keeping it under wraps," Chin-Hong said. "It's potentially more vaccine-evasive as well as transmissible but not as transmissible as Delta."
Dr. Chin-Hong said the aggressive Delta variant is overtaking other variants. Delta makes up more than 90 percent of new cases in the state and around the country.
Riverside County public health officials believe Delta is responsible for most of the cases here at home as well. "The majority of cases that are occurring in our county are also of the Delta variant," said Dr. Kim Saruwatari, director of Riverside University Health.
Only certain tests are sequenced for variants. County officials said only 267 cases of Delta have been sequenced, but there are believed to be many more than that.
"In certain cases, we prioritize people who are traveling we are prioritizing people who have been vaccinated," said Jose Arballo, a spokesman for Riverside County public health. It's more likely that somebody who is vaccinated – if they get sick, it's probably from a variant."
County officials said Lambda isn't present here in the valley or in Riverside County. "We have not observed it – yet," Arballo said.
He said that means there isn't cause for concern with Lambda, at least right now, but experts say the virus continues to mutate every two weeks as long as it's being transmitted.
"Probably the best answer is not even to worry about the variants by all getting vaccinated," Chin-Hong said.
Vaccines are proving effective at preventing serious illness from the variants out there now. But experts said it's a race to get more people vaccinated before a more resistant mutation appears.
Local hospital officials said their focus will remain on the current Delta variant surge.
As far as treatments go, Chin-Hong said it doesn't make a difference which variant a patient has; the clinical care remains the same. However, he said that could change in the future.