Omicron Has a Descendant – Diario Libre

Scientists and health authorities worldwide have their eyes on a descendant of the omicron variant that has been found in at least 40 countries, including the United States.

This version of the coronavirus, which scientists are calling BA.2, is considered stealthier than the original omicron because its genetic traits make it slightly harder to detect. Some scientists fear that it may also be more contagious and say that there is much that is still unknown; for example, whether it evades vaccines better or causes more severe disease.



Since mid-November, more than 30 countries have uploaded nearly 15,000 BA.2 genetic sequences to the global GISAID platform, which allows sharing data on the coronavirus. As of Tuesday morning, 96 of those sequenced cases were from the United States.

“So far, we haven’t seen it start to gain ground” in the United States, said Dr. Wesley Long, a pathologist at Houston Methodist Hospital in Texas, who has identified three cases of BA.2.

The mutation appears much more common in Asia and Europe. In Denmark, it accounted for 45% of all COVID-19 cases in mid-January, up from 20% the previous two weeks, according to the Statens Serum Institut, which reports to the Danish Health Ministry.


The BA.2 subtype has many mutations. About 20 of them in the spike protein are shared with the original omicron variant. But it also presents genetic changes that were not seen in the initial version.

It’s not clear how important these mutations might be, especially in a population that has struggled with the original version of omicron, said Dr. Jeremy Luban, a virologist at the University of Massachusetts Medical School.

For now, the original version, known as BA.1, and BA.2 are considered subgroups of omicron. However, global health experts might give it its own Greek-letter name if it is considered a “variant of concern” of global importance.

The rapid spread of BA.2 in some places raises fears that it could take hold.

“We have some indication that it may be as contagious or maybe slightly more contagious than the original omicron, as it is able to compete with it in some areas,” Long explained. “But we still don’t know why that is.”

A first analysis by scientists from Denmark shows no difference in the number of hospitalizations for BA.2 compared to the original. Scientists in that country are studying the infectivity of this version and the effectiveness of current vaccines to combat it. It’s also unclear if treatments will work against this subtype.

It is also unknown whether a person who has already had COVID-19 caused by omicron can be re-infected with BA.2, but they are hopeful that a previous infection with the initial omicron will reduce the severity of illness if someone later gets BA. .two.

The two omicron expressions have enough in common that infection with the original mutation “would be cross-protective against BA.2,” said Dr. Daniel Kuritzkes, an infectious disease expert at Brigham and Women’s Hospital. Scientists will test whether antibodies from an original omicron infection “are able to neutralize BA.2 in the lab and then extrapolate from there,” he said.


The World Health Organization classifies the omicron variant as worrisome, the most serious among the new coronavirus mutation designations, but does not designate BA.2 with its own name.

However, given its rise in some countries, the agency says research on BA.2 “must be a priority.”

For its part, the UK Health Security Agency has designated BA.2 as an “investigational variant”, noting the increasing number of cases found in the UK and internationally. Even so, the original version of ómicron remains the dominant one in the UK.


The original version of ómicron had specific genetic characteristics that allowed health authorities to quickly differentiate it from delta using a PCR test because the S gene, one of the three “target genes” of the virus, is not detected.

BA.2 doesn’t have this same genetic quirk, so in the test, BA.2 looks like delta, Long said.

“It’s not that the test doesn’t detect it; it’s just that it doesn’t look like omicron”, he said. “Don’t get the impression that we can’t detect the ‘stealth’ variant of omicron. All of our PCR tests can do it.”


Doctors advise the same precautions as always: get vaccinated and follow the recommendations of public health authorities on the use of masks, avoid crowds and stay home if you are sick.

“Vaccines still offer a good defense against severe illness, hospitalization and death,” Long said. “Even if you had COVID 19 before — you’ve had a natural infection — the protection from the vaccine is still stronger, longer-lasting, and actually works well for people who have been previously infected.”

This latest version is another reminder that the pandemic is not over.

“We all want it to be over,” Long said, “but until we get the whole world vaccinated, we’re still at risk of new variants emerging.”


The Associated Press Health and Science Department is supported by the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content.

News and services that extend the global reach of fact-based coverage



Leave a Reply

Your email address will not be published.

5 + 3 =