Editor’s note: Two new strains of the coronavirus that causes COVID-19 called B.1.1.7 and B.1.351 have been found in the U.K. and South Africa and are thought to be more transmissible. In this interview, David Kennedy, a biologist who studies the evolution of infectious diseases at Penn State, explains how these new strains are different, what “more transmissible” means, what that means for the public and whether the vaccines will be effective against them.
There are actually a few different variants that are emerging that you’ve probably been hearing about recently. Two of the most common ones that people are talking about and are most concerned about are the B.1.1.7 and B.1.351 variants. They were first detected in the U.K. and South Africa. It seems that they have been circulating since October at least but were only noticed in December. The concern about these variants is that they might have some differences in how transmissible they are and how the immune system sees them.
The data suggests that both of these variants are more transmissible. Most of the data that’s available is for the U.K. variant in particular. It’s still not clear exactly how much more transmissible it is, but current estimates are that it’s somewhere between 30% and 80% more transmissible than the original strains that were out there.
How did scientists arrive at those numbers? When spikes in cases in the U.K. raised concerns, they sequenced the virus from the cases during the spikes. They saw that there was this novel variant. They looked at the frequency of this variant farther back in time and saw that it was increasing in frequency over time. So it went from being very rare to very common. And based on the rate of increase, they estimate that it was around 70% or so more transmissible than the original virus.
The second way they determined it was more transmissible is through something called the “secondary attack rate.” What they do is, if they know that somebody is infected, they can look and see how many of their contacts got infected. And so they can do that for people who are infected with the original strain of the virus, and they can do that for people who are infected with this novel variant. What they saw was that people who had this novel variant were more likely to infect their contacts, and that increase was about 30% to 40%. So that means that this novel variant is more likely to get passed on to other individuals.
The first thing that I should say is that there’s no evidence that there’s increased disease severity as a result of these variants. So it doesn’t seem like it is now more harmful. But the concern is that more people are going to get infected, and so in total, more people are going to get sick.
But the reason this is so concerning is that you get hit with the increase in transmissibility twice. First, more people will be infected, so it is more likely that you will be interacting with someone who is infectious. And second, the virus is more infectious, so each infected person is more likely to transmit it to you.
With that said, the basics of how we’re supposed to live our lives and how we’re supposed to control this are essentially unchanged. The mitigation measures that we have in place, things like social distancing, wearing a mask, avoiding indoor shared spaces, reducing any unnecessary risks, are still the best measures that we have to try to control this. At least until we all have access to vaccines.
If we look at the smallpox vaccine, we never saw resistance evolve to it. It’s the same for measles, polio and the majority of vaccines that we have. We never have to update them, and they just keep working.
But there have been vaccines where we do have to update them because resistance evolved. And so part of the concern about these new variants is that there might be evolution of resistance to the vaccines that are currently being developed.
The reason people are concerned is that a lot of the mutations in these new variants are in the site targeted by the vaccines, something called the spike protein. But just because we’re seeing changes in the spike protein of these variants doesn’t necessarily mean that it’s going to undermine the vaccine.
What researchers have seen is that one of the mutations found on both the U.K. and South Africa variants doesn’t seem to have any effect on how our immune system sees the virus, so that’s good news. But another mutation found on the South Africa variant does seem to impact how our immune response sees the virus.
We’ve learned that if you take blood serum from somebody who was previously infected with the old version of the virus, and you try to use that serum to stop the virus containing this new mutation, you need a higher concentration of the blood serum to neutralize the virus. That means that there’s a difference in the way that our immune system is seeing the virus. It doesn’t necessarily mean that the vaccine is going to be less effective. But it’s certainly something that needs to be studied more.
These are two of the mutations. There are many more mutations in these variants, which scientists need to continue to study.
The summary here is that at least one of the mutations seems like it could be relevant, but there isn’t good evidence to suggest that means the vaccines are not going to be effective. Vaccines tend to be robust against evolutionary change. And so my hope and my expectation is that the vaccine protection will be robust.
Health workers are at higher risk of COVID infection and illness. They can also act as extremely efficient transmitters of viruses to others in medical and aged care facilities.
That’s why health workers have been prioritised to get a COVID vaccine when it becomes available in Australia.
But just because health workers are among those first in line to receive a COVID vaccine, it doesn’t necessarily mean they all will.
Our health systems represent a microcosm of the community. Just like in the broader community, there will be health workers highly motivated to get the COVID-19 vaccine, driven by concern about risk to themselves, their family, and their patients. There will also be those who have medical conditions, those that may not be able to get vaccinated, and staff who are hesitant.
There will also be health workers with questions about the vaccine, who perhaps need further support to help them decide.
Reports from the US track vaccine hesitancy among health workers at around 29%. However, it’s important to note different groups have different reasons for COVID-19 vaccine hesitancy; rates and reasons can vary across and within countries.
Protecting health workers is critical. Achieving high COVID-19 vaccine uptake among health workers will not only protect these critical staff members, it will also support high levels of uptake among the general public.
Personal health workers are the most trusted source of information on the COVID-19 vaccine.
Decision-making around vaccination can be a complex mix of psychosocial, cultural, political and other factors.
Health workers, just like the broader public, may perceive they are at low risk of acquiring a vaccine-preventable disease. They may have concerns about the safety and effectiveness of a vaccine and/or may find it challenging to get vaccinated.
While most health workers understand how vaccines work generally, they may not necessarily be experts across all vaccine types. If we want to ensure they feel comfortable to receive it and advocate for it, then we must address any misunderstanding and concerns health workers may have. This may be focused on the vaccine itself (how it was developed, effectiveness and so on), or the necessity of vaccination.
One strategy that may assist will be to work with middle managers, as they are influential, trusted and can act as vaccine advocates and agents of change. They may also play a role addressing questions or concerns where they arise. If a COVID vaccine becomes an occupational requirement for health workers, hospitals and other organisations need to include middle managers in the development and roll-out of programs. They can then help ensure staff members understand the rationale for the mandate, which staff members are targeted and why.
Investing in the staff responsible for delivering vaccines in the workplace, as well as other potential vaccine allies such as managers, can help reduce COVID vaccine hesitancy among health workers. That will benefit all of us.
In July 1921, a French infant became the first person to receive an experimental vaccine against tuberculosis (TB), after the mother had died from the disease. The vaccine, known as Bacille Calmette-Guérin (BCG), is the same one still used today.
This first dose of BCG was the culmination of 13 years of research and development.
BCG remains the only licensed vaccine against TB and 2021 marks its 100th anniversary.
Today, all eyes are on the rollout of the COVID-19 vaccine. But while the number of people who died from COVID-19 in the last year is shocking, TB kills about the same number of people — about 1.5-2 million — each year, and has done so for many decades.
In fact, it’s estimated that over the last 200 years, more than 1 billion people have died from TB, far more than from any other infectious disease.
Tuberculosis is caused by the bacterium Mycobacterium tuberculosis. It’s transmitted when a person with active TB coughs up aerosol droplets, which are then inhaled by someone else.
There are about 10 million cases of active TB annually, and it’s estimated up to 2 billion people are what’s known as “latently infected”. That means they are not sick and do not transmit the disease, but in about 10% of these people the disease reactivates.
In most TB endemic regions of the world, BCG is given to infants shortly after birth. The vaccination prevents childhood versions of TB and saves thousands of children’s lives annually.
However, the efficacy of BCG wanes over time. In other words, it stops working. Protection against TB is often lost by adolescence or early adulthood.
Importantly, BCG doesn’t prevent active lung TB in adults, the most important driver of ongoing transmission and cause of death.
The World Health Organization has a goal of TB elimination. To do that, we need to find a TB vaccine that also works in adults.
Over the last decades only about 15 new TB vaccine candidates have entered clinical trials (versus 63 for COVID-19 in one year).
Worryingly, many of the most advanced TB vaccine candidates work no better than BCG.
Because the current TB vaccine candidate pipeline is relatively small, these setbacks and trial “failures” mean BCG may remain the gold standard for many years to come.
Despite being 100 years old, exactly how BCG vaccine works is largely unknown. It’s unclear why BCG usually only confers protection against childhood versions of TB or why protection wanes in adolescence.
Given those uncertainties, we can count ourselves lucky the bureaucratic hurdles for vaccine development were significantly lower in the 1920s.
If BCG were developed today, it would probably never be used; the current complex regulatory framework for vaccine development and licensing would likely not allow the use of a vaccine for which nothing or little is known about how it works.
The reasons BCG hasn’t been replaced with a more effective TB vaccine include:
the decline of TB in many Western countries in the 20th century
limited interest from pharmaceutical companies to invest in TB vaccine development
the fact TB research and pre-clinical vaccine development is logistically challenging and requires special biological containment facilities
the short-term and fiercely competitive environment for government and philanthropic research funding makes it difficult for academics to commit to TB vaccine research as a career path.
The pace of COVID-19 vaccine development shows what’s possible when the political will, pharmaceutical interest and funding is there.
While TB is no longer widespread in Australia, it is an issue in remote Indigenous communities.
Papua New Guinea, Australia’s closest neighbour, has high rates of multi-drug resistant TB and low BCG coverage rates. TB has been introduced into Australia via the Torres Strait, with a high proportion of cross-border diagnoses in North Queensland and over-representation of Indigenous children.
Resistance to current TB treatments increases steadily. Treatment of multi drug-resistant TB is hugely expensive and can take up to two years, requiring multiple antibiotics and close monitoring.
Now is the time to put financial and political will into finding a more effective TB vaccine.
2020 taught us pathogens can cause enormous harm to societies and economies. Investment into infectious disease research and vaccine development represents a fraction of the economic cost of a pandemic.
Tuberculosis is a global threat and a public health concern on a scale similar to COVID-19. The development of a new and effective TB vaccine is crucial if TB is to be significantly reduced, let alone eradicated.
Although the anniversary of BCG is cause for celebration, it should also serve as a reminder more needs to be done to combat this deadly disease.
What can we make of Clive Palmer?
This week, he announced his United Australia Party (UAP) would not contest the upcoming West Australian state election on March 13.
After a dismal showing in the October 2019 Queensland poll, where does this leave his political prospects?
American-style populism does not resonate with large numbers of Australians. Australian political traditions are quite different to those of America especially in terms of welfare and health provision. Those who seek to take the populist route find it a hard road.
In the 2019 election One Nation and United Australia combined only managed to win 7.76% of the Senate vote.
Given the small base on which the likes of Palmer and One Nation’s Pauline Hanson have to work, one wonders what they now hope to achieve.
The current situation with COVID-19 might provide a clue as to why they have failed to spark a populist surge in Australia.
Palmer’s major contribution to the COVID world was his unsuccessful High Court challenge to force Western Australia to open its borders.
The last 12 months has demonstrated the significance of “quarantine culture” in Australia, a term first coined by cultural historian John Williams in the 1990s.
The natural instinct of Australians is to close borders against outside threats, be they national or state. The only partial exception to this rule at the moment is New South Wales — the one part of Australia that had a vigorous free trade (or internationalist) political culture in the 19th century.
In late 19th century and early 20th century Australia, writers such as WG Spence and magazines like The Bulletin talked about a desire to “protect” Australia against a harsh outside world and, if possible, limit the operation of international finance. The ideal was an Australia not dependent on the rest of the world.
In this regard, it is also worth recalling that one of the arguments often given for restricting Chinese immigration at the time was they were seen as carrying diseases into Australia.
This was a form of populism — but one quite different to the American version. It sought to protect Australia and Australians from the outside world, not to assert their right to liberty.
The COVID pandemic seems to have reignited this desire to protect Australians from an outside threat. The most remarkable aspect of this development has been the way in which this desire for protection has devolved to the state level.
Moves to close borders and institute quite draconian measures to halt the spread of the virus have been generally popular. Australians, it would seem, are more interested in being protected than they are in asserting their rights to do as they please.
This makes life quite difficult for someone such as Palmer, who has pushed for freedoms and border openings.
No wonder he has decided not to contest the WA state election. He is not in tune with the popular mood, which has strongly backed Labor Premier Mark McGowan’s hard border approach. It is not the time for libertarian populism.
It is difficult to know how long this protectionist attitude will last. One suspects the current situation with China has also fed into it. The mood is one of a threatening world.
From here, two comments are worth making.
The first is political. Prime Minister Scott Morrison will need to cultivate this threatening mood if he is to succeed at the next federal election, which could be held as early as August. He will need to convince Australians he is the leader who will protect them most effectively. This means going slowly, slowly on things such as opening the international border.
The second is economic. Even in the 1890s, the Australian economy depended on international trade through the sale of wool. The idea Australia could operate independently of other countries was a fantasy.
The same is true today. The borders will need to re-open and students and tourists let in.
Morrison will have to perform a juggling act. He must appear to be providing protection even as he appreciates protection can only go so far.
In the meantime, the prospects look grim for populists such as Palmer and Hanson.
The prime minister and his coalition have the opportunity to steal many of their supporters. The pandemic shows that to be successful in Australian politics, leaders needs to pose as the protector of the people, not promise more freedom and more openness.
I suspect Morrison understands this very well.
On Sunday, federal Chief Medical Officer Professor Paul Kelly said most Australians will be offered a vaccine from Oxford-AstraZeneca.
Australia currently has agreements in place to receive 53.8 million doses of the AstraZeneca shot, and 10 million doses from Pfizer-BioNTech.
So how do these two vaccines compare, how will they be used in Australia, and what can we learn from other vaccines?
Both the Pfizer and AstraZeneca vaccines induce immunity but in different ways. They both deliver the instructions for how to make a target on the virus for our immune system to recognise the spike protein.
The Pfizer vaccine packages the instructions up in a droplet of fat, while the AstraZeneca vaccine packages the instructions up in the shell of a virus, the adenovirus.
Clinical trials for both vaccines have shown they’re broadly safe.
In terms of efficacy, the Pfizer vaccine protects 94.5% of people from developing COVID.
The AstraZeneca shot protects 70% of people on average — still pretty good and on par with the protection given by a flu vaccine in a good year.
However, the optimal dose and timing of AstraZeneca’s shots is still unclear. One trial reported 62% efficacy, and another 90%, with a low dose for the first shot and/or longer break between doses possibly improving protection. More studies are underway to define this and the Therapeutic Goods Administration, Australia’s regulatory body, will evaluate new data as it comes through.
In any scenario, the AstraZeneca vaccine will still protect the majority of people that receive the vaccine from disease.
While the Pfizer vaccine was more protective in clinical trials, the AstraZeneca vaccine has other advantages that could make it more appropriate for use outside of clinical trials:
we can make the vaccine here in Australia, so we’re not dependent on a supply-chain from overseas
we can ship and store it easily at normal refrigeration temperatures, while the Pfizer vaccine requires temperatures below -70˚C
we can administer it more easily, potentially in GP offices.
From a logistical perspective, the AstraZeneca vaccine has a major advantage. The ability to distribute vaccines can be almost as important as the vaccine’s effectiveness.
The effect of these advantages on the impact of this vaccine shouldn’t be underestimated. We have lots of people to vaccinate, a low disease burden currently, are far away from the rest of the world in terms of shipping, and Australia is a pretty big country, so distribution to rural and remote communities is a massive hurdle.
It can be helpful to look at the flu vaccine as a contrast. The flu vaccine is far from perfect — it provides moderate protection, with effectiveness varying between different groups of people and from season to season. For example, in the 2015/16 season in the United States, the quadrivalent influenza vaccine (which covers four strains) was about 54% effective against laboratory-confirmed influenza.
People know it’s not perfect, but people don’t generally judge whether they’ll receive a vaccine based on its effectiveness alone. We know from talking to the community that many factors influence motivation, especially perceived risk and severity of infection, and confidence in the safety of the vaccine.
Every year, access to flu vaccines is prioritised to those at most risk, such as people with medical conditions, Aboriginal and Torres Strait Islanders and those aged 65 years and older. The public has confidence in this approach. We need to protect those most at-risk first, and we don’t have an issue doing this day-to-day. We now have a similar challenge with the new COVID vaccines.
The best approach for protecting everyone’s health amid the pandemic is to provide different vaccines to different people according to need and availability, at least in the short term. The best vaccine is always the one you can get to the communities that need it before they urgently need it.
Because Australia is essentially COVID-free at present, it means we’re in a unique situation that permits a “combination” vaccine strategy.
The Pfizer vaccine is perfect for preventing the most extreme outcomes for people at very high risk of infection or disease: people on the frontlines of the fight against COVID and older people or people with high-risk health conditions.
The AstraZeneca vaccine has the ability to protect a large number of people against disease quickly, because we can make it easily and distribute it quickly.
As a result, Pfizer is likely to be prioritised for people with higher risk and AstraZeneca is likely to be prioritised for everyone else.
We won’t all be able to get the Pfizer vaccine straight away, so for many of us the choice in the short term will be between a 70% efficacious vaccine or no vaccine.
We all stand to benefit from a strategy that protects extremely vulnerable groups from severe disease and aims to rapidly generate immunity in the rest of our community.
There may also be other vaccines that become available. Australia is part of COVAX which can distribute a variety of vaccines, and it also has an agreement for a vaccine made by Novavax, pending the outcome of phase 3 clinical trials. There could be other vaccines that emerge or other agreements developed, and Australia’s strategy will no doubt respond to that.
Nevertheless, both the Pfizer and AstraZeneca vaccines are essential tools in our public health toolkit, with vital roles to play in protecting the entire Australian population. We’ll also need to continue to use other public health tools like testing and contact tracing.
Factoring in effectiveness, availability and distribution challenges, a strategy that uses a combination of the two vaccines for Australia is the best of both worlds.
Shane Huntington co-authored this article. He is Deputy Director, Strategy and Partnerships, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne.
Kylie Quinn, Vice-Chancellor’s Research Fellow, School of Health and Biomedical Sciences, RMIT University; Holly Seale, Associate professor, UNSW, and Margie Danchin, Associate Professor, University of Melbourne, Murdoch Children’s Research Institute