Delta becomes globally dominant COVID-19 variant, out-competing other strains: WHO
The World Health Organization (WHO) on Wednesday said that the Delta variant of the coronavirus is now the globally dominant strain. The variant has been detected in at least 185 countries and is out-competing all other strains, including Alpha, Beta, and Gamma. Notably, Delta had led India into a deadly second wave of COVID-19 infections in April and May. Here are more details.
Addressing the media, Maria Van Kerkhove, WHO's technical lead on COVID-19, said the Delta variant has become more fit and transmissible over time, replacing all other variants that are in circulation. "Less than one percent each of Alpha, Beta, and Gamma are currently circulating. It's really predominantly Delta around the world," Kerkhove said. Kerkhove said that Delta has out-competed other variants of concern.
Meanwhile, the WHO has downgraded Alpha, Beta, Gamma, and three other variants—Eta, Iota, and Kappa—to "variants under monitoring." This means that these variants "no longer pose a major added risk to global public health." "This is really due to changes in circulation and that the variants of interest are just out-competed by the variants of concern. They're just not taking hold," Kerkhove added.
After the emergence of various viral variants causing COVID-19, the WHO decided to categorize them to inform the response of the pandemic. It categorizes variants that pose a greater risk as "variants of concern," while other variants are listed as "variants of interest."
Separately, Mike Ryan, WHO's emergencies chief, has warned that a decline in the number of COVID-19 cases is usually followed by a surge. His comment came as many countries have witnessed a dip in COVID-19 cases. However, he maintained that the countries with significant vaccination rates have less to worry about. "It shows us that the vaccines work," he added.
The Delta variant, B.1.617.2, is a mutation of COVID-19, first detected in India in late 2020. The variant is said to have mutations that give the virus the ability of "immune escape," i.e., evade immunity acquired either through prior infection or vaccination. It had triggered the deadly second wave of COVID-19 infections in India and had also led the surge in the United States.