Our knowledge and ignorance of omicron variants

The World Health Organization said that with scientists around the world scrambling to evaluate its multiple mutations, it may take some time to fully understand the threat posed by omicron, a new variant of the coronavirus.

After scientists in South Africa discovered that the new version appeared to be the reason for the surge in COVID-19 infections in the country’s most populous province last week, the stock market plummeted, some public gatherings were cancelled, and countries around the world suspended inbound flights.

Last weekend, the list of countries where new variants were found among travelers increased. Portugal found 13 cases related to the new variant among members of a football club-only one of them had been to South Africa recently.

On Friday, the World Health Organization designated it as a “variant of concern”, which is the most severe designation of a COVID-19 variant, and called it “omicron” as the latest entry in its Greek alphabet classification system. To avoid stigmatizing the country of origin and simplify understanding.


What do we know about OMICRON?

On Sunday, the UN health agency issued a statement on omicron, which boiled down to: We don’t know much about it yet.

It said that compared with other variants (such as highly infectious delta variants), it is not clear whether omicron is more contagious-more easily spread from person to person. It stated that it is not yet clear whether infection with omicron will cause more serious illness, although it cited data from South Africa showing that hospitalization rates there are rising — but it may be just because more people are infected with COVID-19, not particularly omicron.

From more than 200 new confirmed cases per day in recent weeks, the number of new cases per day in South Africa soared to more than 3,200 on Saturday, most of which occurred in Gauteng, the country’s most populous province.

According to Tulio de Oliveira, director of the KwaZulu-Natal Research Innovation and Sequencing Platform, it now causes up to 90% of new cases in Gauteng.

“There is currently no information that the symptoms associated with omicron are different from those of other variants,” the WHO said. It said that there is currently no evidence that COVID vaccines, tests and treatments will reduce the effectiveness of the new version.


Why are scientists worried about this new variant?

So far, the main difference from other variants seems to be that the risk of omicron reinfection may increase-in other words, people who have been infected with COVID-19 may be more likely to reinfect it.

This variant appears to have a large number of mutations in the spike protein of the coronavirus-about 30-which may affect how easily it can spread to humans.

Some experts say this may mean that vaccine manufacturers may have to adjust their products at some point.

Sharon Peacock, who leads the COVID-19 gene sequencing at the University of Cambridge, UK, said that data so far indicate that the mutation of this new variant is “consistent with enhanced transmission,” but said that “the significance of many mutations is not yet known.”

Lawrence Young, a virologist at the University of Warwick, described omicron as “the most severely mutated version of the virus we have ever seen,” including potentially worrying changes that are unprecedented in the same virus.


What makes OMICRON unique?

Scientists know that omicron is genetically different from previous variants (including beta and delta variants), but they don’t know whether these genetic changes make it more transmissible or dangerous. So far, there is no indication that this mutation will cause more serious diseases.

It may take several weeks to determine whether omicron is more contagious and whether the vaccine is still effective against it.

Peter Openshaw, a professor of experimental medicine at Imperial College London, said that current vaccines are “very unlikely” to not work, noting that they are effective against many other variants.

Although some genetic changes in omicron seem worrying, it is still unclear whether they pose a public health threat. Some of the previous variants, such as the beta variant, initially shocked scientists, but in the end they did not spread very far.

“We don’t know whether this new variant can gain a foothold in the area where the delta is located,” said Peacock of the University of Cambridge. “While there are other variants circulating, how this variant will perform is still inconclusive.”

To date, delta is by far the most dominant form of COVID-19, accounting for more than 99% of the sequences submitted to the world’s largest public database.


How did this new variant come about?

Coronaviruses mutate as they spread, and many new variants, including those with worrying genetic changes, usually disappear. Scientists monitor for mutations in the COVID-19 sequence, which may make the disease more transmissible or lethal, but they cannot determine this just by looking at the virus.

Peacock said that this variant “may have evolved in the infected person, but the virus cannot then be eliminated, giving the virus a chance to evolve genetically.” This situation is similar to the alpha variant considered by experts-initially Found in England-also through mutations in immunocompromised people.

Are travel restrictions reasonable?

It depends on who you ask.

Israel prohibits foreigners from entering the country, and Morocco suspends all inbound international air travel. Dozens of countries in Europe, North America, Africa and other regions restrict flights from Southern Africa.

Neil Ferguson, an infectious disease expert at Imperial College London, said that in light of the recent rapid increase in COVID-19 in South Africa, restricting travel from the area is “prudent” and will buy more time for the authorities.

However, the WHO pointed out that the effects of such restrictions are often limited, and urged countries to keep their borders open.

The South African government stated that the country has been treated unfairly because it has advanced genome sequencing technology that can detect mutations more quickly, and has asked other countries to reconsider travel bans.

Source link