Omicron vs. Delta: Comparing COVID’s most worrisome variants - The Mercury News

Since the COVID-19 virus first appeared in December 2019, thousands of variants have emerged — but, until this month, Delta reigned supreme.

case detected in San Francisco on Wednesday and more in New York, Minnesota and Colorado a day later — is a reminder that Delta isn’t the endgame?

While it kept many of the most successful mutations found in earlier variants, including Delta, it also possesses changes found nowhere before?

But the rapid increase in cases across South Africa is concerning — and suggests that omicron is outcompeting Delta in that nation, said Trevor Bedford, an expert on viral evolution and surveillance at the Fred Hutchinson Cancer Research Center in Seattle.

Delta: This variant acquired some mutations that allows it to evade vaccine-induced antibodies — which explains, in part, the problem of vaccine “breakthroughs.”.

Omicron: It shares similar mutations with the earlier beta and gamma variants, which are more resistant to vaccination than Delta.

Scientists are particularly interested in comparing omicron’s fate against the antibodies made by people who only got two doses of vaccine — versus those who got two doses, plus a booster.

Additionally, a newly released study of epidemiological data from South Africa shows a three-fold increase in risk for reinfection due to omicron, when compared to Delta.

According to the journal Science, omicron did not develop out of one of the earlier variants of concern, such as alpha or Delta.

Delta: A report this summer found that people in England with Delta had double the hospitalization risk of those with an earlier variant.

That may be because cases of omicron, so far, are in predominantly younger people