After leading the nation three weeks ago in becoming one of only three states to move out of the CDC's red tier indicating high overall COVID transmission, California is now the only state in the yellow or "moderate" tier.

Connecticut is the only other state in the nation not in the red tier currently, and it is still in the orange or "substantial" tier where California was on September 14. Vermont has since moved back to the red tier. And the only other place in the yellow tier currently is the territory of Puerto Rico.

California's move to "moderate" is thanks to a statewide seven-day average case rate that dropped from from 95.3 per 100,000 residents to 41.3 per 100,000 over the past two weeks.

California's testing positivity rate also dropped from around 3% to 2.6% in that same span.

The last and lowest tier for transmission, which no state has been in for months, is the blue or "low" tier — roughly equivalent the California health department's former Yellow tier. California will qualify for this tier once we reach fewer than 10 daily cases per 100,000 residents.

High rates of vaccination in California's most populated counties are likely helping this along, in combination with the reimposed masking orders that occurred during July and August's Delta variant surge. And state health officials continue to say that new cases are predominantly occurring among unvaccinated residents.

According to a release from the state Department of Public Health, the rate of new cases among unvaccinated residents aged 16 and over is eight times higher than the rate among the vaccinated — 57.41 per 100,000 residents, versus 7.12 per 100,000. This is being borne out in data in other states, and current hot spots for the virus like North Dakota and Alaska are also hotbeds of antivaxx conspiracy theories, Trump fandom, and general distrust of science and the government.

In California, 49.8 million vaccine doses have been administered to date statewide, and 84.4% of the eligible population now has at least one shot.

According to the CDC's indoor masking recommendation from late July, areas of the country in the "substantial" or "high" transmission categories should still be mandating masks in indoor public spaces. So, with California now in the "moderate" tier, mask orders may soon be loosened — but we'll see.

No one wants to slide backwards again — and it's not like the bars and clubs are really making people keep those masks on anyway, as Mayor London Breed showed.