ONE of the Oxford scientists who co-developed AstraZeneca’s COVID-19 vaccine defended its safety on Friday and said he was not worried that some countries had opted to restrict its use amid concerns about a possible link to very rare side effects.

Adrian Hill, director of the Oxford University’s Jenner Institute, said teams around the world were working to pin down any potential mechanism for what might be causing the blood clots, using real world data now so many shots have been administered.

He agreed with medicines regulators in Britain, and Europe, and with World Health Organization experts, that the risk-benefit balance for the coronavirus shot favoured its use.

“If some countries choose to use one (COVID) vaccine, there will be more of the other vaccines for other countries,” Hill told Reuters. “We don’t see this as a huge issue.”

More than a dozen European countries had suspended use of AstraZeneca’s COVID-19 vaccine, called Vaxzevria, amid reports of cases of the clots combined with low platelets in a very small number of people who had received it. Many countries have resumed using the shot, but with some restrictions.

After reviewing the safety reports, the European Medicines Agency (EMA) regulator said that while there was a possible link, a direct causal link had not been established and the vaccine’s benefits in preventing severe COVID-19 disease were substantial.

Asked whether he was surprised by the reports of blood clot cases occurring in Britain, Norway, Germany and other countries that have been rolling out Vaxzevria, Hill said such extremely rare side effects would not have emerged even in large-scale trials involving tens of thousands of participants.

“Nobody can detect something that occurs in one in 300,000 – and maybe causes death in about 1 in a million – if you’re doing studies of the order of 10,000 to 20,000 vaccines,” he said.

“These very, very rare side effects are very hard to pick up with any vaccine. What’s good is that we can now pick these up – because the data linkage infrastructure in the UK and many other countries is able to do this remarkably quickly.”

AstraZeneca’s vaccine uses a non-replicating cold virus known as adenovirus to deliver spike proteins into cells and produce an immune response.

Hill said the potential mechanism behind any possible link between the vaccine and the rare blood clot cases was “a matter of intense research by many groups around the world”, including teams at the Jenner Institute and at AstraZeneca.

“It may or may not take a long time to figure out,” he said. “I think we’ll be able to do it reasonably quickly and hopefully come up with an immunisation regimen or approach that effectively completely avoids this issue. But we need to … learn more before that.”

Source - Thomson Reuters Foundation

TECHNICAL experts at the World Health Organization (WHO) will review on April 26 Chinese drugmaker Sinopharm’s COVID-19 vaccine for possible emergency use listing, to be followed by the Sinovac jab on May 3, the agency said on Thursday.

“We would expect a decision a couple of days later,” the WHO said in response to a Reuters query.

So far COVID-19 vaccines made by Pfizer, AstraZeneca and Johnson & Johnson have received a WHO listing – an endorsement of their safety and efficacy that helps to guide countries’ regulatory agencies.

Source - Thomson Reuters Foundation

THE World Health Organization’s Emergency Committee has recommended that proof of vaccination not be required as a condition of international travel, maintaining its stance on the issue under growing debate.

The independent experts, in a statement issued yesterday, cited limited evidence on whether vaccination against COVID-19 reduces people’s ability to transmit the virus and “the persistent inequity in global vaccine distribution”.

States should recognise that requiring proof of vaccination deepens inequities and promotes unequal freedom of movement, the panel said.

GENEVA (Reuters) - The world can bring the global COVID-19 pandemic under control in the coming months provided it distributes the necessary resources fairly, the head of the World Health Organization (WHO) told a news briefing on Monday.

Global climate change activist Greta Thunberg, joining the briefing as a virtual guest from Sweden, took a swipe at “vaccine nationalism” and said it was unethical that rich countries were prioritising their younger citizens for vaccination ahead of vulnerable groups in developing countries.

“We have the tools to bring this pandemic under control in a matter of months, if we apply them consistently and equitably,” said the head of WHO, Tedros Adhanom Ghebreyesus.

However, he also expressed concern over the “alarming rate” at which COVID-19 is spreading in those aged 25-59 worldwide, possibly due to much more contagious variants.

“It took nine months to reach one million deaths; 4 months to reach 2 million, and 3 months to reach 3 million.”

Thunberg said that whereas one in four people in high-income countries had now been vaccinated against COVID-19, only one in more than 500 people in poorer countries had received a shot.

“Vaccine nationalism is what is running the vaccine distribution,” she said.

“The only morally right thing to do is to prioritise the people who are most vulnerable, whether they live in a high income or a low income country.”

ENVIRONMENTAL DAMAGE

Thunberg also drew a direct link between the pandemic and the environmental destruction that she said made it much easier for dangerous viruses to leap from animal populations to humans.

“Science shows we will experience more frequent, devastating pandemics unless we drastically change our ways and the ways we treat nature ... We are creating ideal conditions for diseases to spill over from one animal to another and to us,” she said.

Thunberg urged young people everywhere to get vaccinated if given an opportunity, even though they are the age group least at risk from COVID-19, out of “solidarity with people in the (high) risk groups”.

A leading WHO epidemiologist, Maria van Kerkhove, told the same briefing that the latest surge in COVID-19 infections worldwide included increases among age groups previously less affected by the pandemic.

“We are seeing increased rates of transmission across all age groups,” she said, adding that some 5.2 million cases were reported last week, the highest weekly increase since the start of the pandemic.

“We are seeing a slight age shift in some countries, driven by social mixing,” she added.