Continues to spread Coronavirus disease The virus produced a variant of the Greek alphabet, the naming system used by the World Health Organization (WHO), to track new mutations in the virus that caused SARS-CoV-2. Some people have equipped the virus with better ways to infect humans or escape vaccine protection.
Scientists are still focusing on Delta, which is now the main variant in the world, but is tracking other variants to see what happens to replace it one day.
Florida is hit by the deadliest wave of COVID-19 to date, fueled by a surge in Delta variants
Delta-still dominant
The Delta variant, first discovered in India, remains the most worrying. It has attracted the attention of unvaccinated people in many countries and has proven to be able to infect a higher percentage of vaccinated people than its predecessors.
The WHO classifies Delta as a variant of concern, which means it has been shown to increase infectivity, cause more serious diseases or reduce the benefits of vaccines and treatments.
Shane Crotty, a virologist at the La Jolla Institute of Immunology in San Diego, said that Delta’s “superpower” is its ability to spread. Chinese researchers found that people infected with Delta carry 1,260 times more virus in their noses than the original version of the coronavirus. Some studies in the United States have shown that the viral load of individuals infected with Delta vaccine is comparable to that of unvaccinated individuals, but more research is needed.
Although the initial coronavirus takes up to 7 days to cause symptoms, Delta can cause symptoms two to three days faster, giving the immune system less time to react and defend.
Lambda-in decline
Lambda variants have attracted attention as a potential new threat, but the coronavirus was first discovered in Peru in December and seems to be fading.
According to data from GISAID, a database that tracks SARS-CoV-2 variants, although cases involving Lambda increased in July, reports of this variant have been declining globally in the past four weeks.
The WHO classifies Lambda as a variant of interest, which means that it carries mutations that may cause changes in infectiousness or cause more serious diseases, but it is still under investigation. Laboratory studies have shown that it has mutations that resist vaccine-induced antibodies.
Mu-a watch
Mu, previously known as a variant of B.1.621, was first discovered in Colombia in January. On August 30, the WHO designated it as a variant of interest because it had several related mutations and assigned it a Greek letter name.
Mu carries key mutations, including E484K, N501Y, and D614G, which are associated with increased infectivity and decreased immune protection.
According to the WHO communiqué issued last week, Mu has caused some larger outbreaks in South America and Europe. The WHO reports that although the number of genetic sequences identified as Mu has fallen to less than 0.1% globally, Mu accounts for 39% of the sequenced variants in Colombia and 13% in Ecuador, and its prevalence “continues to increase.”
The global health agency said it will continue to monitor Mu’s changes in South America, especially in areas where it co-spreads with the Delta variant. Maria van Kerkhove, head of WHO’s Department of Emerging Diseases, said that the global spread of this variant is decreasing, but it needs to be closely monitored. At a press conference last week, the White House’s chief medical adviser, Dr. Anthony Fauci, said that US officials are paying attention to the matter, but so far, Mu has not been regarded as a direct threat.
still on the way?
Getting more people vaccinated against COVID-19 is crucial, because the large number of unvaccinated people provides more opportunities for the virus to spread and mutate into new variants.
Experts say that this effort must be strengthened internationally to prevent mutations from appearing unscrupulously among the populations of poor countries where few people are vaccinated.
Even so, although current vaccines can prevent serious illness and death, they cannot prevent infection. The virus can still replicate in the nose, and even in vaccinated people, they can spread the disease through tiny atomized droplets.
Dr. Gregory Poland, a vaccine developer at the Mayo Clinic, said that defeating SARS-CoV-2 may require a new generation of vaccines to stop the spread. Prior to this, Poland and other experts said that the world is still vulnerable to the new coronavirus variants.
