Scientists are developing a variety of second-generation Covid vaccines to expand protection against the disease.
Candidates include a version that can provide immune defense against many different variants of the virus, while other researchers are investigating vaccines that would generate responses specifically designed to block the transmission of the disease.
Other projects include research on creating several vaccines that could each handle different strains of the virus, but would be administered as a single injection in a similar way to the annual flu vaccines, which currently combine four vaccines against different strains of the flu virus .
Currently, Covid’s vaccines are designed to prevent infected people from becoming seriously ill, to prevent hospitalizations and deaths. It is not yet known how effective they are in blocking viruses that pass from one person to another.
“There is no indication that any of the new variants of the virus that have recently emerged are causing more serious illnesses than the original virus,” said Professor Jonathan Ball, a virologist at the University of Nottingham. “However, there is evidence that some of these new variants may be better at infecting and therefore spreading in populations that already have partial immunity after natural infection or vaccination.”
One possible solution is a vaccine – now under development by a team of scientists including Ball – that targets not only the spike protein on the surface of the Covid virus, but also another part of the virus, called protein N.
“Hopefully, this should result in a much broader immune system response and thus provide much broader immunity to the virus,” Ball said. Observer. “And given what we now know about the emergence of variants of the Covid virus, it could help us strengthen protection against the disease,” he added.
The project, which also involves the immunology firm Scancell and researchers at Nottingham Trent University, has reached an early stage of manufacturing the new vaccine.
Ball said he hoped clinical trials of the vaccine could be launched soon.
“The plasmid that forms the basis of the vaccine has already been used in other medical treatments and is well tolerated by patients,” he added. “So we are hopeful that we can proceed with clinical trials relatively soon.”
A different approach is being taken by scientists at the University of Bristol, who have started to develop a vaccine that can induce antibodies in the nose and throat.
“This is the route by which the virus infects a person, so if you could specifically target to generate antibodies in the mucous membranes of the upper airways, you could help prevent the virus from infecting someone or being transmitted,” said Adam Finn, professor of pediatrics at Bristol Medical School, University of Bristol.
“In fact, you would be creating the antiviral equivalent of United Nations blue-helmeted soldiers who control war zones and prevent invasions.”
To try to achieve this, Finn and his colleagues are measuring the levels of antibodies in the mucous secretions of people who have received different vaccines against the disease.
“By comparing the strength of these immune responses, we can predict how effective they are in preventing transmission,” he added. “And from there, we could identify vaccines that are best able to prevent the virus from spreading from one person to another – in contrast to current vaccines that are evaluated primarily on how well they prevent the development of Covid’s symptoms.”
This point was supported by Deborah Dunn-Walters, professor of immunology at the University of Surrey: “The vaccines we developed last year are undoubtedly incredible achievements, but they are not the end of the story.
“We started with vaccines that may provide us with about two-thirds of protection against serious diseases and maybe 50% protection against the transmission of the virus. What we have to do is improve this. There is still a lot of work to be done if we are to defeat Covid. “
Analyzing the numbers
After a year with some of the most disheartening news that has plagued the nation in modern times, there has been a dramatic shift in reports about how we are doing in the battle against Covid-19. According to a number of different criteria, the prospects for the UK to emerge from the blockade, in the relatively near future, look increasingly strong.
The number of hospitalizations, deaths and new cases has plummeted in the past three weeks, while the UK’s vaccination program continues to exceed that of most other industrialized nations. Scientists recommended caution about moving too fast in response to this flood of good news. However, there is now a palpable feeling that a significant change in the country’s fortunes is taking place.
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This point was summarized by epidemiologist Mark Woolhouse of the University of Edinburgh last week: “The data looks a lot better than anyone could have imagined two or three weeks ago. Therefore, we must certainly be able to take a more optimistic stance on what is now safe to do. “
To be sure, other research suggests that the Pfizer and AstraZeneca vaccines – which were designed primarily to prevent serious illnesses – also reduce the transmission of the virus from one person to another – although it is unclear how much. A relatively high level of blocking transmission would have an additional significant impact on reducing the pandemic.
But perhaps the most encouraging of all statistics comes from Israel, which has been the most energetic nation on the planet in vaccinating its population. With most elderly citizens as a priority, it has – as a result – seen hospitalization rates for people over 60 plummet compared to those of younger age groups. It is a dramatic illustration of the vaccine’s effectiveness and has clear implications for the UK, where early signs also suggest that Covid jabs – in addition to blocking measures – are starting to reduce mortality rates.
“The performance of the vaccine is really good news,” said Woolhouse. “You never know how clinical trials will translate into a true mass vaccination program. But the numbers look very good. Vaccines protect very well against serious diseases. “