Latest in Omicron

The Centers for Disease Control’s weekly variant proportions data update today offered the clearest indication yet that a new Omicron strain dubbed BA.4.6 may be able to outcompete now-dominant BA.5 in the United States. While BA.4.6 has been in the U.S. since at least May, it remained below 2% of new cases sequenced…

Just one week after BA.5 had outcompeted all other Covid strains become dominant in the U.S., a new highly-mutated Omicron subvariant has arrived which may begin the cycle all over again. According to the World Health Organization, “BA.2.75 has nine additional mutations in the spike compared to BA.2.” Some of those…

Last December 15, as the original Omicron wave gained serious momentum, California reinstituted a statewide indoor mask mandate. State Public Health Officer Tomás Aragón said the move was “to add a layer of mitigation as the Omicron variant, a Variant of Concern as labeled by the World Health Organization, increased…

Today, the more-infectious Omicron BA.5 subvariant is officially the dominant Covid strain in the U.S. Up until how, BA.5 has been tied to its sister Omicron subvariant, BA.4, as both had steadily outcompeted BA.2.12.1 — which itself had been driving cases for the past month or so. After the original Omicron variant…

Residents of the vast majority of California’s 58 counties should be wearing masks, according to the CDC. That’s because 40 of those counties are now designated communities with “High” Covid levels. Less than one month ago, the number was 13. The decision to return to mandated face coverings is not up to the CDC…

Ahead of the July 4 weekend, Los Angeles County today reported 6,529 daily Covid infections, which is very nearly the highest total the county has seen since early February. Only the 7,209 recorded on May 31 is higher. L.A. County Public Health Director Barbara Ferrer said earlier this week that daily infection…

A little over a month after the more transmissible BA.2.12.1 Omicron subvariant became officially dominant in the U.S. on May 24, two sister subvariants of Omicron have quickly eclipsed BA.2.12.1 across the country. BA.5 and BA.4 are, like BA.2.12.1, more transmissible, but have the added advantage of reportedly being…

The BA.5 Omicron variant, first identified in South Africa on February 26, now seems to have an edge in the competition for dominance across the United States. Three Covid variants are currently on the rise as the country experiences a summer surge in cases. All are members of the Omicron family. While BA.5 still only…

Under current Centers for Disease Control and Prevention guidelines, 13 of California’s 58 counties moved today into “high” levels of Covid and are supposed to require masks in indoor public spaces. They include some of the state’s most populous counties, like Santa Clara and Sacramento as well as some of its…

Estimates released by the Centers for Disease Control and Prevention today indicate that the share of cases tied to Omicron variants BA.4 and BA.5 increased 79% in the past week. That means, even as the more transmissible BA.2.12.1 Omicron subvariant became officially dominant in the U.S. last week, it’s already being…

Two months is all it took. In mid-March, Omicron BA.2.12.1 and sister subvariant BA.2.12.2 made up only 1.5% of newly-sequenced positive tests in the U.S. Today, they comprise 57.9% of all new positive Covid test samples sequenced to determine the variant involved. And that roughly 58% is likely just about all…

There’s a growing chorus from public health officials being heard across the country this week, and it consists of one just word: “Masks.” Los Angeles County Public Health Director Barbara Ferrer on a Zoom with reporters today recommended, “Everyone two years of age and older should wear a mask in indoor gatherings…