The Delta variant of the coronavirus has set off alarms around the world for its tendency to go global compared to other strains. However, What is its real risk? Is it more lethal? Does it defy vaccines?
The director general of the World Health Organization (WHO), Tedros Adhanom Ghebreyesus, warned this Friday that this particular lineage of the virus, already detected in 98 countries, is causing the pandemic to be in a “very dangerous” moment.
The Ethiopian expert warned that the Delta “rapidly becoming dominant”, because it is more contagious than the variants previously detected, and that “no country is completely safe” because it can continue to mutate.
However, according to experts consulted by Efe, the global alarm stems from an issue of population proportions, which put many vulnerable and collapsed health systems in check again, and not the increased lethality of the virus.
Health workers take a fever in Sydney, Australia. Photo Bloomberg
From where they come?
As Julián Villabona-Arenas, researcher at the London School of Hygiene & Tropical Medicine (LSHTM) explained to Efe, the “delta variant (B.1.617.2) it was detected for the first time in India last February ”, although the WHO has data from the end of 2020.
Scientists have called “Delta Plus” to “A slightly different version of the Delta variant“, Which, according to Villabona-Arenas, has” an additional mutation -K417N- that affects the viral spike, the protein that adheres to the cells it infects. “
On this small variation, Public Health England, the UK public health agency, it has records from at least April of this year.
The WHO, as its director pointed out this Friday, has called this group as a variant of concern, that is, a lineage of the coronavirus that needs greater epidemiological surveillance due to its distribution throughout the world.
Are they more contagious?
Experts from the Pan American Health Organization (PAHO), the WHO subsidiary in America, responded in a live broadcast to several questions sent by Efe about the evolution of these variants, especially in alert regions such as America.
In his appraisals, Jairo Mendez-Rico, PAHO Advisor for Viral Diseases, considered that “it has been seen that the variants have become more contagious “, which has guaranteed the success of its dissemination in so many territories.
However, they are not more lethal nor do they cause various symptoms.
“There is no scientific evidence to say that it is more aggressive or that is generating more deaths”, He said, clarifying that it is a matter of proportions.
“If I have more infected people, there is a greater chance that these people will become seriously ill and eventually die, but it is an effect of the ratio and not an effect of the virus“, full.
Regarding that, “there is also a question circulating as to whether the Delta variant is killing more young people, but it is simply a perception”, Explained the scientist.
“As in many countries the population with the highest risk, which are the elderly, began to be vaccinated, then the virus is moving. And in young people, who in fact have relaxed with the measures, the virus is moving and there we begin to see a large number of infected ”, he completed.
“It is not because the virus is infecting young people more, it is because it is moving because we are protecting other populations more”, He commented.
What is the real risk?
“The theme of variants, which we have been hearing for a long time, it is a normal theme within the process of evolution and mutation of the virus, which has been happening since the beginning of the pandemic, ”Mendez-Rico clarified in the PAHO broadcast.
According to the WHO, this is a natural process in a viral disease, as has been seen before with dozens of variants of other viruses such as the common flu that, although more transmissible, they have not generated more risk.
However, the current global alarm is not unfounded. This has been detached from the inability of multiple healthcare systems in various regions of the world to withstand a new emergency, since in many cases they are still collapsed.
Asked if the appearance of these variants will lengthen the pandemic, Villabona-Arenas he thinks it “most likely” will.
“These variants are causing a worldwide wave, again increasing the pressure on all health systems. Accelerating vaccination is essential at this time “, he warned, especially about the situation in America.
There, he said, there is “a significant risk given the fraction of adults who have not even received a dose of the vaccine. (…) Therefore, these variants pose a greater threat for those countries with the lowest vaccination coverage ”.
So far in that region, according to PAHO experts, “Delta has been involved mainly in cases of travelers and in a limited way in terms of immune transmission (in 14 countries), it is not yet generating a big explosion ”.
Are vaccines effective?
“As they are more transmissible variants, the effectiveness of vaccines to prevent infections may decrease, but not so the effectiveness of avoiding hospitalization and death, because finally it is the same virus ”, Heriberto García Escorza, director of the Institute of Public Health of Chile, clarified bluntly, in conversation with PAHO.
Mendez-Rico also assured that “the good news is that so far the vaccines that have been licensed it is seen that they are efficient against all these variants ”.
“Some protect in a better way than others, but all reduce the possibility of serious disease,” he said.
From the perspective of LSHTM, Villabona-Arenas believes that “some of the mutations in these variants may contribute to immune escape”, although “There is not enough evidence yet to conclude this with high confidence ”.
“In either case, both AstraZeneca and Pfizer generate broad antibody responses and seem to be performing well with regard to protection against severe disease, “he closed.
South African scientists reported Friday that Johnson & Johnson’s single-dose vaccine also yields positive results in that country against the Delta and Beta variants.