Covid Delta Variant: Herd immunity ‘not a possibility’
Herd immunity is "not a possibility" with the current spread of the Delta variant due to it still infecting vaccinated individuals, the head of the Oxford Vaccine Group Andrew Pollard said.
Pollard, who was involved in the development of the Oxford/AstraZeneca Covid-19 vaccine, told the UK's All-Party Parliamentary Group on coronavirus that, unlike measles — where 95 percent vaccination of the population would stop transmission — the same couldn't be said for coronavirus spread by the Delta variants.
"That does mean anyone still unvaccinated at some point will meet the virus," he warned on Tuesday.
Pollard said that vaccines may slow the process of transmission, with data indicating that people who are vaccinated and test positive seem to be shedding the virus for a slightly shorter period of time.
However, given the circulation of the highly transmissible Delta variant vaccination wouldn't stop spread altogether.
"We are in a situation with this current variant where herd immunity is not a possibility because it still infects vaccinated individuals," he said.
"I suspect that what the virus will throw up next is a variant which is perhaps even better at transmitting in vaccinated populations. So that's an even more of a reason not to be making a vaccine program around herd immunity."
Pollard explained that one of the strongest arguments for vaccinating children is to protect adults, reports Politico.
However, he said that vaccinating children wouldn't completely stop transmission and that there was an urgent need to ensure adults are vaccinated the world over.
Countries around Europe are currently discussing whether to offer a vaccine to all teenagers — with varying decisions being made.
The coronavirus pandemic has killed at least 4,314,196 people worldwide since the virus first emerged in late 2019, according to an AFP compilation of official data yesterday.
'DISGRACEFUL'
The World Health Organization on Tuesday urged the 20 leaders with the power to overturn the "disgraceful" global imbalance in access to Covid-19 vaccines to reverse the tide before October.
The WHO's Bruce Aylward said the world should be "disgusted" -- and asked whether the situation could have been any worse had there been an active effort to block the planet's poor from getting vaccinated.
The UN health agency has been increasingly infuriated by what it sees as the moral outrage of rich countries hogging vaccine supply while developing nations struggle to immunise their most vulnerable populations.
Aylward, the WHO's frontman on accessing the tools to fight the coronavirus pandemic, urged people to tell politicians and business tycoons that it was electorally and financially safe to increase vaccine coverage in poorer nations.
"There's probably 20 people in the world that are crucial to solving this equity problem," he told a WHO social media live interaction.
"They head the big companies that are in charge of this; they head the countries that are contracting most of the world's vaccines, and they head the countries that produce them.
"We need those 20 people to say, 'we're going to solve this problem by the end of September. We're going to make sure that 10 percent of every country... is vaccinated'."
BOOSTER SHOTS EVIDENCE GAP
The WHO wants every country to have vaccinated at least 10 percent of its population by the end of September; at least 40 percent by the end of this year, and 70 percent by the middle of 2022.
Last week, the WHO called for a moratorium on Covid-19 vaccine booster shots to address the drastic inequity in dose distribution -- though several wealthy countries are going ahead regardless.
The WHO says there is no convincing picture as to whether boosters are actually necessary, given the level of protection offered by the WHO-authorised vaccines.
"There's no scientific evidence yet that we need to have a third dose," said Mariangela Simao, the WHO assistant director-general for access to medicines, vaccines and pharmaceuticals.
On the topic of vaccine hesitancy among healthcare workers, Simao said it was "mostly a high-income country problem".
"If you have access to a vaccine and you're a healthcare worker and you're not taking it, there's something very wrong with your information or the system you're working with," she said.
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