LONDON (AP) — Three-quarters of Britain's adult population has received at least one dose of a coronavirus vaccine, the government said Wednesday, as it warned that “deadly” misinformation was undermining the global inoculation effort.

The Department of Health said that 75.2% of people 18 and over in the U.K. have received a shot, and 49.5% are fully vaccinated after two doses.

Britain is racing to vaccinate all adults and curb a more contagious delta variant of the virus, which was first identified in India and is spreading rapidly in the U.K.

The U.K. has recorded almost 128,000 coronavirus deaths, the highest toll in Europe. A mass vaccination campaign that started in December has brought new infections and deaths down sharply, but confirmed cases are once again rising, though daily deaths remain low.

British Health Secretary Matt Hancock called the 75% milestone a big step forward, but he warned that “a worldwide pandemic of misinformation” threatened the vaccination campaign.

“The speed of misinformation is a deadly threat,” Hancock said at an international meeting organized by Britain to encourage vaccine uptake.

The one-day Vaccine Confidence Summit, attended virtually by diplomats, politicians and academics who included U.S. coronavirus response chief Dr. Anthony Fauci and Dr. John Nkengasong, director of the Africa Centers of Disease Control.

Heidi Larson, a professor of anthropology who leads the Vaccine Confidence Project at the London School of Hygiene and Tropical Medicine, said the pandemic had heightened issues around vaccine misgivings that had “been brewing for a while.”

“COVID has laid bare a lot of underlying issues of trust and distrust” Larson said, At the same time, the digital revolution sped information and misinformation around the world.

She said when European nations flip-flopped on administering AstraZeneca shots — which has been withdrawn or limited in some countries because of a link to rare blood clots — it “shook the confidence of a number of African countries” in the vaccine.

“That global knock-on effect is another phenomenon we’re seeing in a different light,” said Larson, who spoke at Wednesday’s meeting.

She said the best thing governments could do was to bridge “the massive divide in access to vaccines” around the world.

Wealthy countries have scooped up hundreds of millions of doses, while supply problems and reluctance by nations, including Britain, to share doses before their own populations are fully inoculated has slowed a United Nations-backed effort to distribute vaccines to low- and middle-income countries.

Vaccine supplies will be high on the agenda when Hancock meets Thursday with health ministers from the Group of Seven rich nations at Oxford University, where the AstraZeneca vaccine was developed. British Prime Minister Boris Johnson is due to host U.S. President Joe Biden and the other G-7 leaders at a summit in southwest England next week.

Britain’s government has faced strong criticism for missteps in handling the pandemic, including hesitation about putting the country into lockdown in March 2020 and testing failures that saw people with the virus released from hospitals to nursing homes, where thousands of residents died.

But its vaccination campaign has been widely praised. Britain secured early contracts for multiple vaccines — four of which have been approved for use — and has used medics, soldiers and volunteers to give more than 65 million doses at thousands of sites.

Hancock said Britain had bolstered vaccine confidence by using “trusted voices” — including naturalist David Attenborough and Queen Elizabeth II — to disclose that they had received a shot and to deliver a pro-vaccine message.

He said another key factor was ensuring the process was fair, by giving vaccines first to the elderly and those at most risk, then moving down the age groups in an orderly way.

“We Brits love queuing,” Hancock said. “And there’s nothing more upsetting than someone jumping the queue.”