Coronavirus Australia news: COVID-19 deaths in the United States hit another one-day high as infections near 23 million
Questions from the audience
If you are fortunate enough to receive the Covid vaccine in Australia with a lower efficacy rate and then another vaccine with a higher efficacy rate becomes available, will you be able to have a “double dose” to improve your overall efficacy rate? Additionally, how would you know if a vaccine does give you ANY cover?
Morning, Trevor — this is a really interesting one.
For a bit of context for those reading, earlier this month the United Kingdom announced it would allow people to be given shots of different COVID-19 vaccines on rare occasions — for example, if the same vaccine dose was out of stock (you can read more on that here).
But there is a lack of evidence about the extent of immunity offered by mixing doses.
Reuters did a bit of a deep dive into it, and expert opinion was split.
Some scientists said that while there was no evidence to support the strategy of mixing vaccine doses from different manufacturers — a method known as heterologous prime-boost — evidence from other vaccines provided some reassurance.
“Based on previous studies which combine different vaccine types, a combination of the AstraZeneca and Pfizer vaccines is likely to be safe,” said Helen Fletcher, a professor of immunology at LSHTM.
But Eric Topol, a genomics expert and director of the Scripps Research Translational Institute, called the mix-and-match strategy “a big mistake” with “unpredictable” results.
Morning Bridget . I wish you were staying on the blog today. I want .to know more about the new virus mutation detected in Japan.
That’s correct, Natty, Japan has detected a new mutant strain from Brazil.
Japan’s health ministry announced it had detected the variant in four travellers from Brazil’s Amazonas state, which had 12 mutations — including one also found in highly infectious variants discovered in England and South Africa.
The four people are in their teens and 40s and were detected by the country’s airport quarantine checks after arriving at Tokyo’s Haneda Airport earlier this month.
The country notified the World Health Organization (WHO) on Monday and further analysis on the variant is underway.