It is still unclear how long the vaccine would protect a person against the virus, whether a single or double dose would be required, and that it needed to be stored at very low temperatures
SCIENTISTS have warned that the Covid-19 vaccine candidate that has been described as 90% effective in preventing the virus may not be made available to the general South African public due to global demand and stringent storage requirements.
Epidemiologist and infectious diseases specialist Professor Salim Abdool Karim was speaking following Monday’s announcement by Pfizer and BioNTech SE that the Covid-19 vaccine candidate trial had been a success.
Abdool Karim said while there were more than 200 different Covid-19 vaccine candidates, 11 of which were in advanced stages of testing, this vaccine provided new information and was the first to use messenger RNA technology.
“It is a game-changer in scientific terms to know that a vaccine against this virus is possible, and that we have one in the making,” he said.
Abdool Karim said the vaccine seemingly worked particularly well, which was unusual at this early stage.
“It’s still early days, so we have to wait until we see their full results but, certainly, the early evidence is very reassuring,” he said.
He added that while the vaccine was good news, it was important to determine what the limitations were.
He said it was still unclear how long the vaccine would protect a person against the virus, whether a single or double dose would be required, and pointed out that it needed to be stored at very low temperatures.
“The vaccine needs to be stored at -70°C. In fact, it must be stored in fridges that are not normally available except in laboratories like mine,” he said.
As a result, Abdool Karim said the vaccine would not be easy to roll out because of the stringent cold-chain requirements. He said that due to the volume of doses that would need to be produced, it may take a while before South Africa got access to it.
“It’s not a vaccine we can use on our general population – we don’t have the fridges for it. Where it would be valuable is in the first groups that we are planning on vaccinating, and that’s health-care workers,” he said.
Abdool Karim said South Africa could only get a small number of doses due to the global demand.
Dr Essack Mitha, the principal investigator at the Newtown Clinical Research Centre, which is a private clinical trial site, said he was not aware of South Africa expressing an interest in obtaining the vaccine.
“I do think it’s possible, but I think it would need the Department of Health to engage with Pfizer,” he said.
Mitha said that if Pfizer proved the effectiveness of the trial, the Food and Drug Administration in America could grant an emergency use authorisation to licence the production of the vaccine.
He said the vaccine was cheaper to make than traditional vaccines, produced faster and did not contain any animal by-products.
Mitha said the vaccine could be used by people who had allergies, and those who had kosher or halaal requirements.
WITH tropical heat, remote island communities and a dearth of ultracold freezers, many Asian countries aren’t betting on Pfizer’s experimental vaccine solving their Covid-19 crisis any time soon.
The world cheered on Monday when Pfizer Inc announced that its shot, jointly developed with BioNTech SE, was more than 90% effective based on initial trial results.
Yet health experts cautioned that the vaccine, should it be approved, was no silver bullet – not least because the genetic material it’s made from needs to be stored at temperatures of minus 70ºC or below.
Such requirements pose a particularly daunting challenge for countries in Asia, Africa and Latin America, where intense heat is often compounded by poor infrastructure that will make it difficult to keep the “cold chain” intact during deliveries to rural areas and islands.
That is a problem for everyone in the world, given that the World Health Organization estimates about 70% of people must be inoculated to end the pandemic, and Asia alone is home to more than 4.6 billion – or three-fifths of the global population.
Some Asian countries are prioritising containing the novel coronavirus rather than looking to stockpile vaccines, while others are looking for alternatives to the messenger RNA technology used by Pfizer that requires such ultra-cold storage.
“On the cold chain requirement of -70ºC, that is a hefty requirement. We do not have such facility,” said the Philippines’ Health Secretary, Francisco Duqu. “We will have to wait and see for now,” he added. “The technology Pfizer is using is new technology. We don’t have experience with that, so risks can be high.”
Pfizer said that it had developed detailed logistical plans and tools to support vaccine transport, storage and continuous temperature monitoring.
“We have also developed packaging and storage innovations to be fit for purpose for the range of locations where we believe vaccinations will take place,” it said.
Yet even wealthier nations like South Korea and Japan are managing expectations.
“Storage is going to be a big challenge for us,” said Fumie Sakamoto, infection control manager at St Luke’s International Hospital in Tokyo. “I’m not sure how well prepared our government is with regards to maintaining the cold chain. Hospitals in Japan usually do not have ultra-cold freezers, but it’s high time we started thinking about the logistics for the vaccine.”
Japan is among three countries in Asia Pacific that have announced supply deals for the Pfizer/BioNTech vaccine. It has signed a deal for 120 million doses, while Australia has secured 10 million doses and China’s Fosun has secured 10 million doses for Hong Kong and Macau.
Japan’s PHC Corp, which supplies medical freezers, said that demand had shot up 150% this year and that they were increasing production to meet demand.
Kwon Jun-wook, an official at South Korea’s Disease Control and Prevention Agency, said it wanted to see how vaccination progressed in other countries first and would thoroughly review its supply chain.
The country had recently experienced the problems of cold storage when it had to discard 5 million doses of flu vaccines because they were not stored at recommended temperatures.
A 2018 study commissioned by the agency found that only a quarter of 2 200 private clinics it surveyed had medical refrigerators, with 40% using household refrigerators.