The SARS-CoV-2 virus’s Delta variant now contributes almost all of the coronavirus contagious cases over the world. Meanwhile, many global areas have witnessed the out-of-control spread of this unusual coronavirus, making the situation even worse.
Scientists are concerned, even though vaccines have proven effective in protecting patients from severe disease and preventing deaths from Delta so far, as Reuters reported.
The Delta’s most “outstanding” feature
According to Shane Crotty, a virologist at the La Jolla Institute for Immunology in San Diego, the Delta’s most “outstanding” characteristic is its transmissibility. As a result, it is more than two times as infectious as previous SARS-CoV-2 variants, causing more infected cases than the virus’s earlier forms, according to the U.S. Centers for Disease Control and Prevention.
Delta’s symptoms emerge two to three days sooner than the original ones, meaning the immune system lacks time to build a defense against the attack.
The virus amount detected in Delta infected patients’ noses is approximately 1,200 times more than that of the original version. Moreover, vaccinated and unvaccinated individuals, who get infected with Delta, have the same virus quantity; and both can infect others with the virus. However, the vaccinated people spend a shorter period spreading the virus because the virus that can potentially shed falls more quickly.
The Delta’s coverage
Among variants, Delta is the most daunting version of the SARS-CoV-2 virus. The WHO stated that among all genomic sequences reported to public databases, Delta accounts for 99.5% and has “surpassed” other variants in most countries.
Due to its capability to increase contagiousness, bring more acute diseases, and resist vaccines and treatment, Delta is categorized as a variant of concern by the World Health Organization (WHO), as Reuters reported.
India was the first country to discover a Delta-infected case in December 2020.
South America is a crucial exceptional case. Other variants, previously known as possible global threats, particularly Gamma, Lambda, and Mu, are dominant, making up a considerable portion of claimed cases, while Delta spreads more slowly there.
The Delta’s descendants
Delta’s global dominance has made several vaccine experts predict all upcoming variants will come from Delta’s descendants.
AY.4.2 appears remarkable as Delta’s “grandchild,” concentrating mainly in the UK, where it accounts for around 10% of sequenced virus samples. Scientists are researching the possible advantages of two additional mutations in the spike protein of A.Y.4.2, which the virus uses to enter cells.
According to a preliminary analysis, the AY.4.2 “Variant Under Investigation” by the UK Health Security Agency is somewhat more contagious than Delta.
According to WHO, at least 42 countries, including the United States, report infected cases of AY.4.2.
Although current vaccines have proven their effectiveness in reducing severe disease and death risk, they can’t stop virus transmission. As a result, the virus keeps duplicating in patients’ noses, spreading through tiny, aerosolized droplets, even among vaccinated people.
According to Dr. Gregory Poland, a vaccine developer at the Mayo Clinic, the invention of a new generation of vaccines, stopping infection, is demanded as an approach against SARS-CoV-2. But, Poland said, until then, the world is still at high risk.