Stealth Omicron Symptoms: Are They Different From Other COVID-19 Variants?

Omicron's "stealth" subtype, which has put scientists on alert due to its rising number of cases, did not appear to be more contagious or harmful than other variants of COVID-19.

The new variant — dubbed BA.2 — is harder to detect through PCR tests since it does not exhibit a tell-tale marker on its spike protein that was previously used to monitor the original BA.1 variant, The News reported.

BA.2 also has other mutations and additional genetic changes not seen in BA.1, but Chicago Department of Public Health Commissioner Dr. Allison Arwady claimed "it's still omicron," according to NBC 5 Chicago.

"[T]his isn't even a new variant, it's just considered a slightly different flavor of the kernel and we've seen that before," Arwady said.

There have been no "major differences" in age distribution, vaccination status, breakthroughs or risk of hospitalization among BA.2 cases, Healthline reported, citing early data on the subvariant.

Kristen Nordlund, a spokeswoman for the Centers for Disease Control and Prevention (CDC), also claimed that there was "insufficient data to determine whether the BA.2 lineage is more transmissible or has a fitness advantage over the BA.1 lineage," according to The Washington Post.

While omicron can mutate as it infects new people and multiplies, the "majority" of those mutations or genetic changes are "harmless and have no impact," Dr. William Schaffner, an infectious diseases professor with the Vanderbilt University Medical Center, was quoted as saying by the outlet.

"It would be difficult for any variant to be more contagious than omicron, and there is no indication that the [BA.2] is more contagious," Schaffner said.

As for its symptoms, BA.2 did not appear to have any unusual symptoms compared to omicron and other COVID-19 variants, said The News.

However, doctors still advised people to get vaccinated and follow public health guidance about wearing masks, avoiding crowds and staying home when sick to protect themselves.

"The vaccines are still providing good defense against severe disease, hospitalization and death. Even if you’ve had COVID 19 before — you’ve had a natural infection — the protection from the vaccine is still stronger, longer lasting and actually... does well for people who’ve been previously infected," Dr. Wesley Long, a pathologist at Houston Methodist in Texas, was quoted as saying by NBC 5 Chicago.

The World Health Organization has not given BA.2 a designation as it does not consider the subtype to be a "variant of concern," but the international agency recommended investigations into it to be "prioritized independently (and comparatively) to BA.1."

The U.K. Health Security Agency, meanwhile, designated BA.2 a "variant under investigation" Friday, following "increasing numbers of BA.2 sequences identified both domestically and internationally."

BA.2 has been detected in 49 countries, with the subvariant accounting for less than 1% of all COVID-19 cases worldwide, according to Poynter.

There were at least 127 known BA.2 cases in the United States as of Friday, CNBC reported, citing a global database that tracked coronavirus variants.

The U.S. has reported a total of 74,037,216 COVID-19 cases and 879,971 virus-related deaths, data provided by the CDC showed.