When Will Covid Be Defeated? You’ll Need Patience: Coronavirus Q&A
With coronavirus deaths globally approaching 1.3 million, the world needed some good news when Pfizer and German partner BioNTech became the first companies to announce positive results from a late-stage vaccine trial. But there are still plenty of unanswered questions about the virus and the potential weapons to combat it. I asked Michael Kinch, a vaccine specialist at Washington University in St. Louis, and virologist Marion Koopmans at the Erasmus University Medical Center in Rotterdam, about the risks and challenges that lie ahead.
James Paton: Michael, the results showing the Pfizer and BioNTech vaccine is more than 90% effective in preventing Covid-19 is the big news this week. With cases surging past 10 million in the U.S. and rising in many other parts of the world, we desperately need an exit strategy. Does this suggest we could soon have a way out of the crisis and is the euphoria justified?
Michael Kinch: It seems likely that the end of the crisis can now (finally) be envisioned but nonetheless will require more patience (a commodity that is becoming ever more scarce). Although it may feel that it has taken eons to reach this point, from a historical perspective, this vaccine was developed remarkably efficiently (both in terms of time and money). This outcome reflects a truly amazing collaboration amongst private and public sector entities. Once this crisis has resolved, 2020 will likely be regarded by future generations as an extraordinary accomplishment, perhaps likened to the Apollo program.
The logistics confronting a national rollout will be daunting, even more so given certain features of the current vaccine. Specifically, the ultra-low freezers needed for the storage of mRNA vaccines (such as that developed by Pfizer and BioNTech) are expensive and prone to failure. These limitations will likely challenge a roll-out of the vaccine to the larger population.
Paton: Marion, even if a vaccine crosses the line soon, it doesn’t mean the pandemic is over. Is there a risk that countries and the public will let down their guard, allowing the coronavirus rampage to continue, and how long do you think measures like the restrictions that are sweeping across Europe will need to remain?
Marion Koopmans: Given the number of vaccine candidates, I have no doubt that some vaccines will reach the finish line of an approved product. The expectation for that is the first quarter of 2021. But we need to be cautious, despite promising results, we know little at this stage, particularly two questions: What the vaccine performance will be in those that will benefit most and will vaccines that come to the market impact on transmission. The vaccine candidates are quite different in the type of response that they induce, and therefore the choice of how to best use them may differ.
Another challenge is obvious: how to scale up production to the degree that will be needed. In practice, that means that we need to plan for seeing vaccines becoming one of the measures that we have to control the circulation of this virus. The combination will be necessary, I would expect at least for another year, but with more and more room to move depending on how much testing capacity is available, how much vaccine, and what the compliance is of people to physical distancing and other recommendations.
Paton: Michael, you’ve cited the vaccine obstacles that remain. Thinking about the positive Pfizer headlines, let’s focus on the data and what we don’t yet know. There are a number of unanswered issues, from safety to how long the protection may last. What do you see as the biggest question, and how much is still unknown?
Kinch: Given the small amount of data that we presently have (evidence that 90% of those vaccinated seemed to have been protected), a key question pertains to those who were not protected. Specifically, are there potential commonalities (based for example on age, gender, race or even individual genetic information) that might identify vaccinated populations that continue to remain at-risk.
This information will be essential, both to save individual lives and to create settings (e.g., in the workplace) intended to protect those individuals. For example, it might be important to continue to wear masks for those working around those individuals or to allow them to work from home. If there are no commonalities based upon obvious demographics, then it will be essential to identify if there are tests (e.g., antibody levels in the blood) that might predict these individuals, who remain susceptible despite immunization.
Paton: Marion, a question for you. A vaccine will take time to deploy globally and strides in finding therapies to combat Covid-19 won’t pay off right away. Winter will hit before many people are able to roll up their sleeves, and the virus is continuing to spread, what should we expect over the next few months in Europe and the U.S?
Koopmans: Correct, for the coming months, what we have is the current package of control measures: physical distancing, hand washing, movement restrictions, mouth masks etc. Once the number of new cases go down, the combination with tracing of contacts will need to provide information for where to focus control measures.
Paton: Marion, it’s unclear if this vaccine will prevent severe cases, if it works in the elderly, how many will benefit. Do people need to manage their expectations and prepare for a vaccine with limitations? What should we expect a vaccine to accomplish in stopping the spread of the virus?
Koopmans: Yes, the vaccines will not provide 100% protection from severe disease. I do expect considerable impact, so reduced rates of complications, less need for hospitalization, less need for ICU admission. But this will also depend on the question whether the leading vaccines will provide a good immune response in (older) risk groups.
Paton: Michael, I wanted to follow up on the distribution challenge. This Pfizer-BioNTech vaccine won’t be simple to deploy because it needs to be stored at ultra-cold temperatures, and immunizing people requires two doses. Does that mean other vaccines following Pfizer could have an edge?
Kinch: Undoubtedly, we will identify and deploy other vaccines without the extreme liabilities that will complicate logistics. Both of the features you mentioned (extreme refrigeration and multiple dosing) will be addressed over time and, for example, the Johnson & Johnson vaccine touts the feature of single-dose protection.
However, I would not count Pfizer, Moderna or the other vaccines out quite yet. They are undoubtedly parallel tracking (at-risk) efforts to improve the stability of the vaccine such that it requires less restrictive refrigeration conditions. This process, known as formulation, can work wonders (it is its own science), and Pfizer and other large companies have considerable experience with this.
That said, the mRNA vaccine is an entirely new way of delivering vaccines. Bear in mind that there has not yet been an FDA-approved mRNA vaccine, and so we have very little experience with formulation or manufacturing (especially at large-scale conditions). So, there is more than a bit of “trial by fire” happening.
Paton: Marion, I wanted to shift gears for a moment and get your view on an issue you know very well. Denmark said a rare mutation of Covid-19 in the country’s mink farms has the potential to hurt the development of a vaccine. How likely is that to compromise vaccines, and what are the implications here that are worrying scientists?
Koopmans: What they saw is indeed that the virus has been circulating in mink and picked up some mutations. That always happens, also in humans so by itself it’s not so problematic. But the Danish public health institute found some mutations in the part of the virus that binds to the receptor and then showed that antibodies from humans that had Covid were a bit less effective in blocking the virus infection in cells.
This does not mean that current vaccines will not work against these viruses, but it is a warning to keep monitoring what is happening. That needs to be done as much for the circulating viruses in humans, but the warning is also to make sure there is no hidden circulation in large groups of animals.
Paton: Marion, having a vaccine is one thing. Vaccinating people is another. There is growing concern about the levels of uptake we will see once a shot is ready. Some people inevitably will be reluctant, but it depends on what kind of shot we have. How much of a threat is that to achieving a level of immunity needed to knock out the virus? What trends are you seeing in Europe?
Koopmans: Yes, there is some concern about uptake. This is a clear-cut anti-vaccination movement, as has been the case across the world, but it is important to focus on the people that would consider vaccination but have concerns: will these vaccines be safe?
How can it be that normally it takes many years to develop vaccines, and now it is within a year? Are corners being cut? Those types of questions. There are very good answers for that, but I think that information needs to be explained very well. So I think we need to do better at explanations, essentially.
Paton: Michael, you are in the U.S. The case numbers look grim. We have a fresh story out right now saying Texas’s Covid-19 caseload topped 1 million. It’s playing out in many places around the world. What’s the best strategy governments can take while we wait for vaccines and therapies? What’s the most prudent approach and message nations should deliver to the public?
Kinch: Sadly, the numbers are truly grim… and likely to get far worse. The nation is exhausted and not wanting to curtail those activities that are contributing to the rising infection rates. This is particularly true as we enter the holiday season.
Nonetheless, the most prudent approach is to socially distance and wear a mask. We should take hope that a vaccine is feasible and relish that for now. To put it bluntly, if you refuse to wear a mask and socially distance, those around you are more likely to die a premature death. Although we are all desperate to return to a “normal life,” we must think about our friends and neighbors and appreciate the risks that will continue if we fail to take the most basic precautions.
Source: Read Full Article