The rapid advance of the Omicron variant of the coronavirus has health authorities on alert.
On Monday, January 10, the United States reported a record of 1.35 million new infections, the highest daily figure of any country, according to data from Reuters.
On Tuesday, the World Health Organization (WHO) warned that the half of the population in Europe It will have been infected with the omicron variant in the next 6 to 8 weeks.
And on Wednesday, the Pan American Health Organization (PAHO) reported that due to Omicron, Covid-19 infections in America almost they doubled in the last week.
“Infections are accelerating in every corner of the Americas and, once again, our health systems are facing challenges“Said Carissa Etienne, the Director of PAHO.
At BBC Mundo we explain some aspects of Ómicron and why experts warn that should not be considered a mild illness the one that causes this variant.
1. Why is the Omicron variant so contagious?
According to epidemiologist Maria Van Kerkhove, WHO technical leader for Covid-19, there are three main reasons:
- This variant of the virus developed mutations that allow it to stick more easily to human cells.
- We have “Immunity escape”. That is, people can be reinfected even if they have previously had the disease or have been vaccinated.
- Ómicron replicates in the upper respiratory tract, which makes it easier for the virus to spread, unlike the delta and other variants that replicate mostly in the lower respiratory tract; that is, the lungs.
The Covid Vaccine Hub portal indicates that it is difficult to estimate how transmissible omicron is compared to other variants, but that some estimates from the UK Health Security Agency indicate that it may be between 2 and more than 3 times more contagious than the delta.
The Centers for Disease Control and Prevention (CDC) state that Ómicron “is likely” to spread more easily than the original SARS-CoV-2, but that it is “not yet known” how easily it spreads compared to delta.
The CDC indicates that Anyone infected with Omicron can spread the virus, even if she is vaccinated or has no symptoms.
2. What are the symptoms?
According to the Zoe Covid Symptom Study, led by Tim Spector, an epidemiologist at King’s College London, so far it is known that the most common symptoms of the Omicron variant are:
- Runny nose
- Headache
- Fatigue (mild to severe)
- Sneezing
- Throat pain
The UK National Health Service (NHS) indicates that we must continue to monitor the classic symptoms of Covid:
- Sudden continuous cough
- Fever or high temperature
- Loss or change in taste and smell
3. Does omicron cause less severe disease than the delta variant?
The CDC says more data is needed to find out whether omicron infection causes less severe or fatal disease compared to other variants.
Some indicators, however, give signs that in some cases omicron can cause milder symptoms, but can still cause hospitalization and death, especially in people who are not vaccinated.
On December 31, the UK Health Safety Agency published a report showing that people infected with omicron had a one-third likely to end up hospitalized compared to those infected with delta.
In the portal of the Department of Public Health Sciences of the University of California Davis, the epidemiologist Lorena García indicates that the symptoms of omicron can be very different between vaccinated and unvaccinated people.
“In those who are fully vaccinated and boosted, the symptoms tend to be mild. On the contrary, if a person is not vaccinated, the symptoms can be quite serious and cause hospitalization or even death, ”says García.
WHO has warned that Ómicron it should not be seen as a mild illness.
“Although omicron seems to be less serious compared to delta, especially in vaccinated people, that does not mean it should be classified as mild, “warned WHO Director Tedros Adhanom Ghebreyesus in early January.
“Like previous variants, Ómicron is causing hospitalizations and killing people ”.
4. Do vaccines work against omicron?
People with two doses remain protected against hospitalization, even if they have lost part of their protection against infection, according to Ignacio López-Goñi, professor of Microbiology at the University of Navarra, Spain, in an article published on December 28 in The Conversation.
A study by MIT and Harvard University published on January 7, indicates that two doses of Pfizer or Moderna “do not produce antibodies capable of recognizing and neutralizing the omicron variant” but that “A booster dose dramatically improves protection against Omicron.”
Andrew Lee, Professor of Public Health at the University of Sheffield, England, indicates that the data shows that two doses of the Pfizer or AstraZeneca vaccines offer limited protection against omicron, but that protection is seen quickly restored with a booster dose, as explained in an article by The Conversation January 5.
Lee also points out that it is normal that some people inoculated get infected with omicron, since vaccines are not designed to prevent infection, but to reduce the chances that someone who has been infected will develop a serious disease or die.
“So far, vaccines have proven very good at preventing serious disease,” says Lee.
The CDC indicates that “the emergence of omicron emphasizes the importance of getting vaccinated and take the booster dose ”.
On January 11, a WHO panel indicated that Covid-19 vaccines may need to upgrade to ensure they are effective against newer variants like Omicron.
5. If I already had Covid or I have already been vaccinated, is it possible that I get the Omicron variant?
A report from Imperial College London from December 17, which is still under review, shows that omicron has great ability to evade immunity that grants a previous infection.
The document estimates that the risk of being reinfected with omicron is 5.4 times higher than with delta.
Protection against reinfection by omicron provided by a past infection can be as low as 19%, the study indicates.
Regarding vaccines, Dr. Gregory Poland, director of the Vaccine Research Group at the Mayo Clinic in the USA, indicates that the protection they offer against omicron goes decaying over time.
“If you receive two doses of the vaccine, after at least 3 months your protection against infection or hospitalization is reduced to around 30% to 40%,” says Poland on the Mayo Clinic website.
Poland indicates that with the booster dose the immunity can be between the 75% and 80%.
“Notice I didn’t say 100%,” Poland warns. “That’s why we still use masks. That’s why we still keep our distance ”.
6. What immunity do I get after having overcome the infection with Omicron?
“What we knew about previous variants is that people with hybrid immunity (vaccinated + infection) developed a more powerful and lasting immune response than those only vaccinated or only infected,” says Mundo Salvador Peiró, a doctor specializing in public health and researcher in pharmacoepidemiology at FISABIO, a biomedical research foundation in Spain.
Peiró, however, warns that Ómicron has been able to infect people who have already had the disease or who have already been vaccinated, at least when a time has passed (more than 5 or 6 months) since the vaccination or infection.
7. Can I get Covid again after I have recovered from Ómicron? Can I get the Ómicron variant twice?
“In theory yes, although reinfections will be extremely rare in the following months after having overcome the covid ”, says Peiró.
Peiró adds that these reinfections will be even rarer in people who, in addition to having overcome the covid, have received one third dose of the vaccine.
The expert indicates that due to how recent the infections are, it is not yet known how long and to what extent these reinfections will occur.
It may interest you:
* COVID: How to detect FAKE N95 and KN95 masks and the best way to store them
* COVID: What are the symptoms of Omicron that you may not have noticed
* Covid: these are the differences between a PCR and the antigen test and which is better
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eldiariony.com
Eddie is an Australian news reporter with over 9 years in the industry and has published on Forbes and tech crunch.