Omicron subvariant B.A. 5 quickly becoming the dominant strain in Arizona

Virus Outbreak Arizona
Posted at 9:04 AM, Jul 19, 2022
and last updated 2022-07-20 21:59:15-04

In the first two years of the pandemic, much of COVID-19 coverage was dedicated to different variants. The UK, now known as alpha, and delta were the two dominant variants that were responsible for two of Arizona’s three COVID-19 surges. Now, coverage of COVID-19 has shifted to subvariants of Omicron. The latest and most contagious so far is B.A. 5.

The new COVID-19 variant has been rapidly spreading across the country and is now estimated to make up more than 60% of new cases,according to the CDC. It is highly transmissible, compared to previous variants, and seemingly more resistant to prior vaccinations and immunities.

The laboratory T-Gen is the state’s largest sequencer of COVID-19. At the beginning of June, B.A. 5 was only 11% of genomes. During the last week of June, it increased to over half.

Dr. Dave Engelthaler is the director of the genomics division at T-Gen. He told ABC15 that Omicron found the right key to the lock and is mutating the spike protein just enough to avoid our built-up immunity.

“COVID-19 will continue to shift just enough so it can continue to spread and evade our immunity and B.A. 5 allows it to do that,” Engelthaler said. “It’s not more dangerous, we’re not seeing more serious cases at all in the hospitals."

The data does support Engelthaler’s assessment of rapid community spread. Wastewater surveillance in North Tempe shows COVID-19 is right now at almost the same levels as the winter Omicron surge. Confirmed cases statewide are significantly lower than last winter, meaning most Arizonans are testing at home and the virus is milder.

Daily hospitalizations for COVID-19 are up since early May, with hospitals now frequently reporting about 700 COVID-19 occupied beds. ICU figures are also up slightly in the same period. However, even with the rise, hospitalizations are substantially lower than the winter surge, which itself was about half the size of the 2021 winter surge.

Going forward, Dr. Engelthaler said that Omicron came out of nowhere so another variant that is more transmissible could at some point overtake it. In the meantime, he says people at very high immunity risk should stay vigilant and he’s hopeful that a vaccine for Omicron will be available in the fall.

"The issue is that this new variant is highly transmissible. It's immune evasive in the sense that if you are exposed to this variant, your previous immunity from vaccination and potentially other variants, likely non-human variants, doesn't necessarily protect you in the same way as previous infections. And so we're going to see increased amounts of breakthrough infections," said John Brownstein, Chief Innovation Officer at Boston's Children's Hospital, professor at Harvard Medical School and ABC News Medical contributor. "Many of those will not turn, of course, into severe illness, but they're turning into infections that ultimately lead to more transmission. And then we'll see the impact in our most vulnerable communities, those that are elderly, immunocompromised, and we'll see history repeating itself. And that's the real concern we have with this new immune evasive variant."