The COVID-19 pandemic is increasingly becoming an arms race among the emerging variants of the virus, and at the moment, there’s no question which one is winning: the Delta variant—formally known as B.1.617.2—one of four strains to have emerged originally in India. It was just last month that the World Health Organization labeled Delta a “variant of concern”—joining with the Alpha strain, which emerged in the U.K.; the Beta strain, from South Africa; and the Gamma strain, first seen in Brazil. But Delta is fast becoming the most worrisome of the bunch.

Health officials are sounding the alarm that Delta threatens to reverse the progress made in countries, like the U.S. and U.K., that have lately been beating the pandemic into retreat and worsen conditions in countries, like India, that are still deep in crisis. Researchers have found that Delta is at least 60% more transmissible within households than the Alpha strain, the dominant variant in the U.S., according to the Public Health of England.

More in category

Officials set up a mobile center at a Missouri fair to boost vaccinations. No one showed up.
July 31, 2021MSNBC
Officials set up a mobile center at a Missouri fair to boost vaccinations. No one showed up.
Tokyo Olympics schedule: Gymnastics events finals highlight Day 9 in Tokyo
July 31, 2021USA Today
Tokyo Olympics schedule: Gymnastics events finals highlight Day 9 in Tokyo
A slice of Princess Diana's wedding cake is going up for auction
July 31, 2021CNN
A slice of Princess Diana's wedding cake is going up for auction
CNN analyst's blunt message to GOP lawmakers on vaccines
July 31, 2021CNN
CNN analyst's blunt message to GOP lawmakers on vaccines
Florida Sets Daily COVID-19 Record With 21,683 New Cases
July 31, 2021Newsweek
Florida Sets Daily COVID-19 Record With 21,683 New Cases
24 Percent of Latina Women Have Lost Family Member to COVID-19: Poll
July 31, 2021Newsweek
24 Percent of Latina Women Have Lost Family Member to COVID-19: Poll
Louisiana hospitals reach capacity as COVID-19 cases surge
July 31, 2021The Hill
Louisiana hospitals reach capacity as COVID-19 cases surge
Smithsonian is building a 2020 artifact collection
July 31, 2021CBS
Smithsonian is building a 2020 artifact collection
Over 100,000 children could face extreme starvation in Ethiopia's Tigray region
July 31, 2021CBS
Over 100,000 children could face extreme starvation in Ethiopia's Tigray region
July 31, 2021CBS
"Global fire crisis:" Why the world keeps burning and what we should do about it
Austin health officials warn there's only 16 ICU beds left in the region
July 30, 2021CBS
Austin health officials warn there's only 16 ICU beds left in the region
Video shows Texas deputy pinning teen to the ground, arresting her mother
July 31, 2021MSNBC
Video shows Texas deputy pinning teen to the ground, arresting her mother
Border Patrol: Agent, 2nd driver killed in crash in Arizona
July 31, 2021ABC News
Border Patrol: Agent, 2nd driver killed in crash in Arizona
19 bodies reburied amid protests in search for Tulsa victims
July 31, 2021ABC News
19 bodies reburied amid protests in search for Tulsa victims
U.S. Sees Spike in Gun, Ammo Sales: 'I've Never Seen Anything Like It'
July 31, 2021Newsweek
U.S. Sees Spike in Gun, Ammo Sales: 'I've Never Seen Anything Like It'
Doctor Warns Sending Children to School Unmasked Will Further Delta Spread
July 31, 2021Newsweek
Doctor Warns Sending Children to School Unmasked Will Further Delta Spread
Retired NFL fullback Anthony Sherman compares COVID-19 vaccination wristbands to racial segregation
July 31, 2021USA Today
Retired NFL fullback Anthony Sherman compares COVID-19 vaccination wristbands to racial segregation
Some COVID hot spots see increase in vaccinations; Massachusetts outbreak shows 'vaccines are working': Live COVID-19 updates
July 31, 2021USA Today
Some COVID hot spots see increase in vaccinations; Massachusetts outbreak shows 'vaccines are working': Live COVID-19 updates
Day 2 of Lollapalooza proceeds amid heightened COVID-19 fears
July 31, 2021KRON4
Day 2 of Lollapalooza proceeds amid heightened COVID-19 fears
Lollapalooza requiring masks at indoor spaces on final 2 days of music festival
July 31, 2021KRON4
Lollapalooza requiring masks at indoor spaces on final 2 days of music festival
Trump defends his comments about election after release of DOJ notes
July 31, 2021The Hill
Trump defends his comments about election after release of DOJ notes