Delta variant of COVID rapidly spreads worldwide

A young woman reacts as she receives a dose of Covishield (COVID-19 vaccine) during a special vaccination drive in Beawar. The first case of the Delta-plus variant of coronavirus in Rajasthan was found in Bikaner, India on June 27, 2021. Photo by Sumit Saraswat/Pacific Press/Sipa USA

The delta variant of COVID-19 was first identified in India and is now surging in the U.K., Israel, and South Africa. In California, the delta variant accounts for nearly 15% of cases. While vaccinations seem to provide protection, public health officials are increasingly concerned about what this means for unvaccinated people. 

USC’s Dr. Edward Jones Lopez says although this variant appears to be more infectious and potentially deadlier, it doesn’t necessarily appear to be a major concern for fully vaccinated individuals. However, he stresses the importance of receiving both vaccine doses. 

He notes that the delta variant results from a natural progression in viruses as they mutate. “There's always new strains. That's what bugs do. They're always trying to avoid the interventions we developed to stop their spread. And the best way they can do that is changing their genetic material to avoid the effect of vaccines.”