Beyond the Delta, scientists are seeing new variants of the coronavirus

The continued epidemic of the Chicago-SARS-CoV-2 virus has given rise to variants of the Greek letter. This is the naming system used by the World Health Organization (WHO) to track for new mutations in the virus that causes COVID-19. Some people have better ways to infect humans with the virus or circumvent vaccine protection.

Scientists continue to focus on Delta, the dominant variant in the world today, but are tracking others to see what happens to that location someday.

Delta still dominates

First detected delta variant in India It remains the most worrisome. It has hit unvaccinated populations in many countries and has proven to be able to infect a higher proportion of vaccinated people than its predecessors.

WHO classifies Delta as a variant of concern. This indicates that deltas can increase infectivity, cause more serious illnesses, and reduce the effectiveness of vaccines and treatments.

According to Shane Crotty, a virologist at the Lahora Institute of Immunology in San Diego, Delta’s “superpower” is its transmissibility. Chinese researchers have found that people infected with Delta carry 1,260 times more virus in their noses than the original version of the coronavirus. Some US studies suggest that the viral load of vaccinated people infected with Delta is comparable to that of unvaccinated people, but more research is needed.

While the original coronavirus took up to 7 days to cause symptoms, Delta can cause symptoms 2-3 days earlier, reducing the time it takes for the immune system to react and begin defense.

Declined lambda

The Lambda variant has been the focus of attention as a potential new threat, but this version of the coronavirus, first identified in Peru in December, appears to be receding.

According to data from GISAID, a database that tracks the SARS-CoV-2 variant, cases of lambda increased in July, but reports of this variant have declined globally in the last four weeks.

WHO classifies lambda as a mutant strain of interest. That is, it has mutations that are suspected of causing infectious changes or causing more serious illness, but are still under investigation. Laboratory studies have shown that there are mutations that resist vaccine-induced antibodies.

Mu is remarkable

Mu, a variant formerly known as B.1.621, was first identified in Colombia in January. On August 30, WHO designated it as a mutant strain of interest and assigned it a Greek letter name due to concerns about some mutations.

Mu has important mutations such as E484K, N501Y, and D614G, which are associated with increased transmission and decreased immunoprotection.

According to the WHO newsletter published last week, Mu has caused some larger outbreaks in South America and Europe. While the number of gene sequences identified as Mu is less than 0.1% worldwide, Mu accounts for 39% of the mutations sequenced in Colombia and 13% in Ecuador, with a “consistent prevalence”. “Increasing”, WHO reported.

The global health agency said it continues to monitor Mu for changes in South America, especially in areas that co-circulate with delta variants. Mariavan Kerkhove, head of the WHO Emerging Infectious Diseases Unit, said the subspecies cycle is declining globally but needs to be carefully monitored. At a press conference last week, White House Chief Medical Advisor Dr. Anthony Fauci said U.S. officials were monitoring it, but so far Mu has not been seen as an imminent threat. ..

More on the way?

Increasing the number of people vaccinated against COVID-19 is important as follows. Large group of unvaccinated people The virus spreads and increases the chances of mutating to new variants.

Experts say that efforts need to be strengthened internationally to prevent uncontrolled emergence of variants among people in poor countries with very few vaccinations.

Still, current vaccines prevent serious illness and death, but not infection. The virus can replicate in the nose, even among vaccinated people. And they can infect the disease through small, aerosolized droplets.

According to Mayo Clinic vaccine developer Dr. Gregory Poland, defeating SARS-CoV-2 is likely to require a new generation of vaccines to stop the infection. Until then, Poland and other experts say the world remains vulnerable to the rise of new coronavirus variants.