The highly transmissible Covid-19 variant, which first appeared in India, is spreading rapidly around the world, health officials say, stepping up the race to increase global vaccinations.
Option B.1.617.2, now called the Delta variant, is in at least 60 countries, including the United States and the United Kingdom, and British scientists recently estimated that it could be 40% to 50% more transmitted than B.1.1. 7 variant or alpha, which in turn is more portable than the original virus and spreads rapidly around the world.
“Given this level of transmission, I expect it to spread around the world,” said Sharon Peacock, CEO and chairman of the Covid-19 Genomics UK consortium, in the middle of The Wall Street Journal’s Tech Health Event.
In the UK, the Delta option is rapidly displacing the Alpha option, and health officials believe it is contributing to an increase in Covid-19 cases and hospitalizations in the country, although it starts from a low baseline. Previously, about 98% of cases in the UK were due to the Alpha option, but the Delta option began to take over after it was introduced in the country in March and now accounts for about 75% of cases, Dr Peacock said. Covid-19 Genomics UK is a consortium of public health and academic organizations that collects, arranges and analyzes genomes from Covid-19 tests in the UK to guide pandemic efforts.
“We are seeing a big change in the cause of the infection in the UK and this change has happened relatively quickly over a period of a few weeks and it doesn’t look like it’s really going to stop,” he said. Peacock, who is also a professor of public health and microbiology at the University of Cambridge.
The option is also becoming dominant in the Democratic Republic of Congo, said John Nkengasong, director of the African Centers for Disease Control and Prevention, at the WSJ conference. Dr Nkengasong said the risk of the variant was significant and that the continued emergence of new variants spoke to the need to strengthen genomic sequencing around the world.
Anthony Fauci, the best infectious disease doctor in the United States, said on Tuesday that the Delta variant currently accounts for more than 6% of Covid-19 sequenced cases in the United States. The Alpha variant is still dominant in the country.
“We cannot allow this to happen in the United States,” Dr Fauci said of the situation in Britain during a White House press briefing. He urged people to get vaccinated, if they haven’t already, and to make sure they get their second dose.
The option may also be associated with an increased risk of serious illness and hospitalization, health officials say, but this link is less secure.
Currently available vaccines work against the Delta variant, suggest early data, but they appear to be slightly less effective, especially after a single dose. According to Public Health England, both AstraZeneca and Pfizer-BioNTech vaccines were approximately 33% effective against symptomatic Covid-19 caused by the Delta variant after a single dose, compared with approximately 50% effective against the alpha variant.
However, after two doses, the efficacy of the Pfizer vaccine against the Delta variant increased to 88% and the AstraZeneca vaccine was approximately 60% effective.
Both doctors. Peacock and Nkengasong have expressed concern that if the virus is allowed to continue to spread, new options may emerge over the next few months that current vaccines may be even less effective.
“I think it’s one step in a series of steps, or there could be a big step toward an option that’s more resistant to vaccination,” Dr. Peacock said. “The way we come up with options is to stop the transmission and vaccinate the world.”
Write to Brianna Abbott at email@example.com
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