The delta variant, which first emerged in India, has now spread in more than 80 countries and is fast becoming the dominant version of the virus.
In places like the UK, the delta variant has dethroned the highly transmissible alpha variant, which was first identified, as the most common form of the virus.
That rapid spread of the delta variant forced health officials to react. UK officials, for example, they delayed plans to reopen the country, moving the date to mid-July.
Health officials in Israel, a nation where nearly 60 percent of the population are fully vaccinated, have reinstated the requirement that residents wear masks in the home, a public health measure that it had been revoked 10 days earlier.
In the United States, places like Los Angeles County recommend that even vaccinated people still wear face masks at home.
The World Health OrganizationIt also urges everyone to continue wearing masks, although the guidelines of the U.S. Centers for Disease Control and Prevention, remain in effect.
The Delta variant poses the greatest threat to unvaccinated people, the latest studies suggest. In the United States, the delta is responsible about 26.1% of cases all over the country.
Its prevalence doubles every two weeks. Narrowing down regions that include states with low vaccination rates like Missouri and Wyoming reveals the delta it is already causing most infections in some places.
On July 1, the Biden administration announced that teams of experts equipped with test and therapy supplies would be sent to U.S. hot spots to control outbreaks of the delta variant.
The concern is even greater globally. Only 23.4% of people around the world have received at least one dose of the COVID-19 vaccine, most of whom reside in rich countries. Less than 1% of people in low-income countries it had a chance.