In the last variant report released Aug. 18, delta was reported to make up 93% of variants circulating in the state. Since then, the DOH State Laboratories Division has detected 236 additional samples with delta to add to the 582 reported then, for a cumulative number of 818, and it now makes up 100% of variants circulating in the state.
It has edged out Alpha, which originated in the United Kingdom, as well as Gamma, which originated in Brazil, and Beta, with origins in South Africa.
It now makes up nearly all to all of the coronavirus cases in all four major counties.
Numerous delta plus variants — identified as AY.1 and AY.25, among others — have also been detected in genomic sequencing of samples collected from June to August.
The delta variant is far more contagious than previous strains, according to the Centers for Disease Control and Prevention, and may cause more than two times as many infections.
CDC classifies delta, first identified in India, as a variant of concern — a variant for which there is evidence of an increase in transmissibility, more severe disease, and reduction in the effectiveness of antibodies generated during a previous infection or vaccination.
CDC said people infected with the delta variant, including fully vaccinated people with symptomatic breakthrough infections, can transmit the virus to others. However, CDC said vaccinated people appear to spread the virus for a shorter time.
The State Laboratories Division conducts whole genome sequencing on 15% to 20% of samples from COVID-positive PCR tests collected statewide.