WHO Monitors for Dangers Posed by New Variants as US Scales Back COVID Response

WASHINGTON — This week the World Health Organization has begun monitoring two new subvariants of the omicron strain known as BA.4 and BA.5, adding to a lengthy tracking list which already includes omicron subvariants BA.2.12 and BA.2.12.1, and the new omicron XE. 

“In general, viruses that evolve either evolve in a stepwise fashion, or in a completely new variant not possessing a lot of features of previous variants,” said John Swartzberg, a professor emeritus of infectious diseases and vaccinology at the University of California-Berkeley’s School of Public Health, during a phone call with The Well News.

“Everything seemed to be going in a stepwise fashion, until the emergence of XE,” continued Swartzberg.

According to Swartzberg, the coronavirus was evolving in a typical stepwise fashion in the original variants of the virus, but omicron was different. 

“The emergence of omicron stood everything on its head, in the sense that this virus didn’t seem to just be an evolution of delta or previous variants but something quite new with many nucleic acid changes,” said Swartzberg.

The new XE omicron strain went a step further than the original omicron strain in its mutation, mixing the original omicron variant and subvariant BA.2 mutations.

XE is a recombinant variant of BA.1/BA.2, which means that it is made up of genetic material from two distinct virus strains in circulation, with the majority of the genome including the S gene belonging to BA.2.

The U.S. Centers for Disease Control and Prevention does not currently indicate on its website that omicron XE is a variant of concern or interest. 

This is despite the fact that initial estimates from the WHO find that XE is 10% more transmissible than BA.2. 

“Whether that is going to pan out, we just don’t know,” said Swartzberg.

In England, 1,125 cases of XE have been identified as of April 5, according to a report from the U.K. Health Security Agency on SARS-CoV-2 variants of concern and variants under investigation.

When it comes to the other variants currently being monitored by the WHO, Swartzberg said the data from the CDC that was released on April 19, and collected through April 16, showing that cases of BA.2.12 account for roughly 74% of all the positive COVID cases in the U.S., and BA.1.2.1 accounts for 19% of all COVID cases. 

“If we go back to two months ago, Feb. 19, about 3.4% of isolates were BA.2.12 and all the rest were BA.1.2.1 isolates,” said Swartzberg.

This means that the BA.1.2.1 and BA.2.12 variants currently account for about a total of 93% of all isolates, pushing the original omicron strain almost completely out of the current case counts. The original omicron strain now accounts for only about 6-7% of positive infections in the U.S., according to Swartzberg. 

The New York State Department of Health announced on April 13 that the BA.2.12 and BA.2.12.1 account for 80.6% of COVID-19 infections in New York, with an estimated 23-27% growth advantage above the original BA.2 variant. 

The spread of new variants and subvariants, according to Swartzberg, is likely to pick up in the coming months, as the federal mask mandate for public transportation on buses, airplanes, and trains, was struck down by the U.S. District Judge Kathryn Kimball Mizelle on Monday. 

“By striking down this mandate, there will be more transmission of the virus. With a high degree of confidence, we know how this virus spreads, and there is no better place than an enclosed place where people are talking than on public transit,” said Swartzberg.

“By definition the more people that get infected the more potential for a variant, and getting rid of the mask mandates just exacerbates the problem,” continued Swartzberg.

So far, there is no evidence to suggest that the new variants and subvariants of omicron are more deadly or infectious than the original strain of omicron or the previous delta strain, but Swartzberg said that the pandemic is still far away from reaching an endemic stage.

Swartzberg said that an endemic stage of any virus means the virus has reached a steady state in the population, such as a seasonal infection like the flu, or rarely causing severe illness, like tuberculosis. 

“There is nothing to suggest we are in a steady state of this epidemic disease. At some point we likely will be, what that could look like could be a variety of things,” said Swartzberg.

Swartzberg said that Delta Airlines released a statement to patrons on Tuesday, when the four largest airline companies in the country announced the end of mask mandate for passengers, that, “COVID has now transitioned to ordinary seasonal virus.” 

“There is no evidence that [COVID] is seasonal at this point. We’ve seen it in the summer, spring, winter, and fall. There is also no evidence that it is ordinary, as it still carries high mortality and morbidity,” said Swartzberg. 

At this time, Swartzberg said that around 4% of the world’s population is in the U.S., but the U.S. still accounts for about 16% of the world’s deaths from COVID, and 16% of the world’s cases. 

Swartzberg said one thing that could move the needle forward in reaching an endemic stage in the pandemic could be the creation of a ‘Pan coronavirus vaccine,’ which is a vaccine capable of protecting against all future variants of COVID and also against influenza. 

“Every coronavirus that exists has sites on it that are common to other viruses. If we can find those sites that can be neutralized with antibodies and if those sites are critical to the virus’ survival, then we can potentially end coronavirus’s reign of terror,” said Swartzberg. 

In the meantime, Swartzberg said the virus will continue to produce variants until it can’t find a human host to infect anymore, which will increase the likelihood of an emerging variant that could invade human immunity.

Swartzberg said that the U.S. has increased it’s monitoring capacity since the start of the pandemic, as the CDC recommended that around 5% of isolates in the country be checked to have a sense of how the virus is evolving, but according to Swartzberg the U.S. was able to get that percentage of data collection up to around 7.5-10%.

The U.S. has already made dramatic cuts to COVID response efforts, such as decreasing PCR testing, and cutting back on funding for whole genomic sequencing.

“My concern is when you cut back on these programs, like closing testing sites or [scaling back] genomic sequencing, what happens when you have a new variant and have to do that in a robust fashion? You have to train those people and get them back to work,” said Swartzberg. 

“I’m concerned we are not monitoring this in real time as we should be,” continued Swartzberg.

Alexa can be reached at [email protected]