From detection to symptoms, what we already know about omicron

Cases of the new variant of the coronavirus, omicron, have already been detected around the world.

Discovered by scientists in South Africa led by Brazilian Tulio de Oliveira, director of the country’s Center for Epidemic Response and Innovation, it has been described as potentially worrying for its number of mutations –50 in total.

Since then, omicron has spread to more than a dozen countries, many of which have imposed travel restrictions to try to reduce its spread.

What tests are used to detect omicron?

PCR (polymerase chain reaction) tests are capable of detecting coronavirus infections.

Depending on which laboratory the swabs (swabs used to collect oral and nasal secretions for testing Covid-19) are sent to, some may also help to identify specific variants such as delta or omicron.

This is what happened with the first cases of omicron identified in Brazil, in São Paulo: after the positive result of the samples in the PCR test, they were sent for a genetic sequencing analysis in the laboratory of the Hospital Albert Einstein, which confirmed that it was the new variant.

Only a few labs have the technology to do this.

The United States leads the world in PCR testing numbers, ahead of the United Kingdom, Russia, Germany, Italy and South Korea, in that order. Brazil is in 11th position in this ranking.

In India, however, only 1% of all samples sent to laboratories can be tested to find variants such as delta or omicron.

How do we know that omicron has spread around the world?

Swabs that tested positive for what appears to be the omicron variant were sent to a laboratory for complete genetic analysis using a technique known as genomic sequencing.

This confirmed that some people were indeed infected with the latest variant of the coronavirus.

This laboratory analysis of the virus’s genetic material is the key to detecting variants and discovering how they work.

Many cases of omicron infection go undetected because it can take a few weeks for the process to complete.

According to South African health officials, omicron has fueled a “worrying” increase in coronavirus cases in the country and has now become the dominant variant.

Michelle Groome of South Africa’s National Institute of Communicable Diseases (NICD) said there had been an “exponential increase” in infections over the past two weeks, from a weekly average of about 300 new cases a day to 1,000 last week, and more recently 3,500. On Wednesday (1), South Africa registered 8,561 cases. A week earlier, the daily count was 1,275.

“The degree of increase is worrying,” said Groome.

According to the NICD, 74% of all virus genomes sequenced last month were from the omicron, found for the first time in a sample collected on Nov. 8 in Gauteng, South Africa’s most populous province and home to the main city in the country. country, Johannesburg.

Since then, the variant has been detected in several countries on five continents, including Brazil.

However, we do not know which countries have the most omicron infections, but which ones detected them earlier.

Do quick tests detect the omicron?

The quick tests don’t show which variant you’re infected with — but they still detect the presence of the coronavirus, including the omicron.

What are the symptoms of omicron?

The World Health Organization (WHO) states that there is no information to indicate that the symptoms of omicron are different from those of other variants – so be on the lookout for a new cough, fever and loss of taste or smell.

Cases of fully vaccinated people in South Africa infected with omicron have been reported, but with a mild picture. The World Health Organization (WHO) in fact reported that, according to preliminary data, omicron appears to cause more cases of Covid-19 reinfection. This, along with its large number of mutations and its apparent even greater ease of spread, are among the factors that have made omicron a “concern variant.”

Angelique Coetzee, the South African doctor who first identified the new omicron variant of the coronavirus, says patients infected so far show “extremely mild symptoms” — but more time is still needed to assess the effect in vulnerable people.

Recently, hospitals in South Africa have seen more young people being admitted with more severe symptoms — but many have not been vaccinated or taken just one dose.

This suggests that receiving two doses and a booster dose is a good way to protect against illnesses caused by the new variant, as well as all others.

What is the difference between omicron and other variants?

The main difference is the number of new mutations –50 in total.

A large number of them –32– are in the so-called S protein (spike or spike) of the virus, key for the pathogen to invade cells and the target of most vaccines.

This is the main concern of scientists.

They found that the omicron has what is known as “S gene target failure”, which makes it very easy to track positive cases related to the new variant.

But not all “S-gene target failures” will necessarily be associated with the omicron — full genomic sequencing is necessary to make sure of this.

What is the role of genomic sequencing?

Analyzing the genetic makeup of the virus is a crucial part of understanding which variant is involved in the infection.

By looking in detail at the genetic material, it can be confirmed whether someone has been infected with omicron or with another widely circulating variant, such as delta.

This method only provides information about the swabs that are analyzed – but, using these results, scientists are able to estimate what proportion of new cases could be linked to the new variant.

Scientists in the UK and South Africa are at the forefront of this technology, which is why most new variants have been detected in these countries. But that doesn’t always mean that they originated there.

Or what do we know about ômicron?

Very little is known about how the variant acts or how threatening it is.

For example, it is unclear whether omicron spreads more easily (though it is suspected), whether it causes more severe cases of the disease compared to other variants, or whether protection from vaccines will be less than previously thought.