Omicron Variant

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A surprising new detail about the Omicron variant has emerged that could at least partly explain its increased transmissibility.

According to new research, the latest coronavirus variant can survive longer on many household surfaces when compared to the ancestral SARS-CoV-2 strain.

"Wow – this other new study shows Omicron survives on most surfaces much longer than the old strain," epidemiologist Dr Eric Feigl-Ding wrote on Twitter, sharing the study.

"Dr Marr is an airborne scientist so she even acknowledges this new concern of Omicron."

He also shared a graph from Dr Linsey Marr, an aerosol scientist at Virginia Tech in America. Marr delved into the findings from the study, in the form of a draft research paper from the Cold Spring Harbor Laboratory.

The research found that the Omicron variant is much more stable than its ancestral strain on smooth and porous surfaces.

Marr said "a new preprint comparing survival of Omicron vs. ancestral strain on surfaces. TLDR Omicron is more stable [probably in aerosols too, may contribute to greater transmissibility, my graph of their data]".

COVID is like Michael Myers in Halloween: Just when you think it’s finally out of the picture, it comes back to threaten you again. COVID cases in the U.S. have been plummeting for weeks, and hospitalizations are near an all-time low. But with another Omicron variant pushing up case numbers around the world, it seems depressingly plausible that at least one more wave — the sixth, if you’re counting — could be headed America’s way.

Omicron BA.2 is similar to the variant that caused this winter’s spike, BA.1. But it has 20 different mutations, four of them on a crucial region of the spike protein. These disparities are likely part of the reason BA.2 appears to be considerably more transmissible than the original Omicron — 33 percent, according to one Danish study. BA.2 is also thought to infect vaccinated people more easily than its forebear, though, fortunately, it does not appear to be any deadlier. First detected in the Philippines in November, the variant spread widely in South Africa and India in December and has since become the dominant strain around the world.

It’s hitting parts of Asia particularly hard.

Because these countries have experienced the pandemic so differently from the U.S. until now, it’s difficult to draw conclusions about what their surges mean for America in the short term. Europe is a better comparison. Like the U.S., it has been pummeled by wave after wave. This winter’s Omicron surge hit the continent hard, but once it peaked, most experts expected infection rates to quickly fall as the population picked up natural immunity. That’s why France re-opened its nightclubs, Austria decided not to enforce its strict vaccine mandate, and Italy announced an end to its coronavirus certificate program. “The skies seem finally to be clearing,” a French government spokesperson said last month.

But they weren’t. Scarcely had the BA.1 numbers begun to fall when BA.2 cases started ramping up. As a result, instead of the clean bell-shaped rise-and-decline we experienced here, infection rates in Europe remained high, and now they’re climbing higher. New cases in the U.K. are up 82 percent over the last two weeks and hospitalizations are up 38 percent.

So what does that mean for the U.S.? Though European surges have been a reliable precursor to stateside waves throughout most of the pandemic, the tea leaves are more ambiguous this time. Cases here are still falling. But an increasing proportion of those cases are BA.2 — up from 5 percent a month ago to 25 percent this week — and viral loads detected via wastewater are rising in some places. The experts are divided as to what it all means.

The case for not worrying
One voice counseling calm is New York Times science reporter Carl Zimmer, who recently noted that epidemiologists don’t believe that BA.2 will cause a massive wave of cases. Among the cited reasons: Our current COVID-19 vaccines are effective against the BA.2 variant, just like they were against BA.1. And the millions of people who were infected with the original Omicron strain have antibodies that protect against BA.2. In other words, the same factors that caused the downslope in BA.1 infections here could keep BA.2 at bay, too.

Nathanie Landau, a professor of microbiology at the NYU Grossman School of Medicine, is sympathetic to this view. The new variant is “quite similar to BA.1,” he says. “I don’t think it’s likely to result in a second wave of infection in the United States.”

Former Food and Drug Administration commissioner Dr. Scott Gottlieb thinks there will be a bump in case numbers, but not a significant wave.

The case for worrying
Among the opposing camp is Eric Topol, a professor of genomics at the Scripps Research Institute in San Diego. “Great to see U.S. COVID-19 hospitalizations down to 23,000 and approaching their pandemic low,” he wrote this week. “But indicators from the new wave in Europe and U.S. wastewater surveillance suggest this may be short-lived.”

Samples taken from municipal sewer systems provide a measure of how much viral material is being produced by all the sick people in a community. Because infected people produce virus particles before they consciously feel sick, wastewater samples provide an early signal of a wave that hasn’t yet shown up in regular COVID-19 testing. According to the CDC, a quarter of its wastewater-testing sites have seen an increase in SARS-CoV-2 RNA levels of 100 percent or more over the last 15 days. Topol has also pointed out how each of the last five U.S. waves were preceded by ones in Europe and the U.K. — and each time the U.S. has paid for its failure to heed those warnings.

If U.S. cases follow Europe’s trend, what lies in store for us might well be worse than for them. U.S. vaccination and booster rates are significantly lower than most European countries. No more than two-thirds of eligible Americans have been fully vaccinated, and about half of the Americans eligible for a booster shot still haven’t gotten one, including a third of seniors. America’s relatively low vaccination rates probably explain why the first Omicron wave hit much harder here than it did in Europe. During the peak of that wave, the U.S. suffered ten times as many COVID deaths as Germany, despite having only four times as many people.

Which is not to say that the Europeans have played their cards flawlessly; they may have worsened the onset of their BA.2 wave by prematurely lifting COVID-19 restrictions. Unfortunately, the United States is following the same path. Forty-nine states have abandoned indoor mask mandates, with the last holdout, Hawaii, set to join the club on March 26.

Walensky also shared recent findings from genomic sequencing that continue to show the predominance of the Omicron variant.

"Essentially a hundred percent of what we're finding now is Omicron," she said. In terms of individual variants, the Omicron BA1 variant is about 3% of circulating virus, the BA2 variant is about 68%, and BA2.121 makes up about 35%.

"We're just starting to learn about the impact of BA2.121," Walensky said. "It appears it might have a transmission advantage of about 25% of over the BA2 subvariant."

From the onset of the COVID-19 pandemic, the elderly have borne the brunt of the virus’ deadly wrath.

Now, newly updated federal data shows that despite widespread vaccination among seniors, virus death rates among older Americans surged to near-record levels during the first omicron wave.

Over 90% of seniors have been fully vaccinated, but about 30% of those fully vaccinated have yet to receive their first booster shot. To date, just under 10 million Americans 65 and older have received their second booster — representing about 28.5% of those who had already received their first shot.

Even with overall high vaccination rates in older populations, nearly three-quarters of the COVID-19 deaths reported in the U.S. have been among people over the age of 65.

Experts say the reason for the renewed surge may be due to a number of factors, including waning immunity, relatively low booster uptake compared to primary vaccination series and general vulnerability to the virus among the group. In addition, the sheer scale of the spread of the virus during the omicron wave was significantly higher compared to prior waves of the virus

Although the number of virus-related deaths in Americans over 75 has consistently been higher than all other age groups, according to data from the Centers for Disease Control and Prevention (CDC), there were some lulls.

As the virus receded in late June 2021, and the group's vacci​nation rate increased, the death rates for those older age groups approached levels comparable to younger people.

However, during the delta wave, in late 2021 and 2022, the disparities in death rates began to increase again with the more transmissible variant, which was better at evading vaccines. They further widened when the omicron wave hit the U.S. in the winter of 2021, a variant that was even more transmissible than delta.

In early January 2022, CDC death data -- broken down by age group per 100,000 people -- shows that people over 75 had a COVID-19 death rate that was 136 times higher than that of people between the ages of 18 and 29. Similarly, people between 65 and 74 had a COVID-19 death rate that was 45 times higher than that of people between the ages of 18 and 29.

During the omicron surge in January, Hispanic Americans over 75 were 2.7 times more likely to die from COVID-19, compared to white Americans and Asian Americans of the same age. They were also 1.7 times more likely to die from COVID-19, compared to their Black counterparts, and 3.7 times more likely to die compared to their American Indian/Alaska Natives.

"Only 38% of those 50 to 64 and 43% of those 65 and older have received a vaccine dose in the past six months. This leaves about 60% of older Americans without the protection they may need to prevent severe disease, hospitalization, and death," CDC director Dr. Rochelle Walensky said during a meeting of the agency's independent advisors in May. "We know immunity wanes over time, and we need to do all we can now to protect those most vulnerable."