Digital contact tracing apps appeared at the start of the pandemic. They let you know if you had been with someone who tested positive and they worked on a regular personal smartphone. So far, they haven’t been a quick fix, and they’ve come under fire for their usability, privacy, etc. But these are already cheap tools in our pockets. Do they have a role to play now, as covid-19 cases continue to climb, especially in the United States?
I spoke about these issues with Dr. Rajeev Venkayya, who served as the White House biodefense adviser under George W. Bush, and was responsible for that administration’s national strategy for pandemic preparedness. After that, he was director of vaccine administration at the Gates Foundation. He now heads the vaccine business of Takeda, a Japanese pharmaceutical company that hopes to manufacture Novavax’s vaccine candidate.
This interview has been condensed and edited for clarity.
Q: Should we be telling people to use a contact tracing app at this point in the pandemic, when a vaccine is on the horizon? What is the use of this technology?
A: First of all, we can take a step back and see where we are in the pandemic. We are in a very difficult situation right now, with an increase in cases of transmission, hospitalizations, deaths happening all over the place. In this context, contact tracing plays a different role than it will be when you have relatively low levels of transmission. It will be unlikely that you will put it back in the box with testing and tracing as your primary tool. It’s like refloating a flooded boat.
Q: So does it make sense for a person to use an app in this context?
A: Absolutely … at an individual level, in fact, it’s more important now to download a contact tracing app than it was three months ago, because there are many more viruses circulating in the community than it is. three months ago. If you go to the grocery store today, even though everyone is wearing masks, you are exposed to other people and you are more likely to catch the virus today than you were three months ago. A contact tracing app will always help you protect yourself as a person … from an individual point of view, it’s always good to know if you’ve been with someone who has covid. It poses a threat to you and the people around you. And of course, you could become a threat to the rest of the community if you wear a covid and don’t realize it.
Q: Will these other ways to fight the spread of covid-19 still be useful after a vaccine is deployed?
A: The vaccine news is amazing. It’s better than most people expected, to see such high levels of efficacy and to see that the first two vaccines are so effective in preventing serious illness. That said, it will take time for companies to provide enough vaccines to stop the pandemic. And in the United States, at most, a lot of people think it will be the middle of next year before that happens. If there are any delays in manufacturing, which happens all the time in vaccines, it will be really important to have all the tools we can have – including robust testing and tracing. You’re just trying to keep pace and limit the damage.
The early days vaccine will be aimed at high-risk populations, which will be healthcare workers and people in long-term care facilities, and then perhaps critical infrastructure workers. Those populations that receive the vaccine will not be enough to stop transmission in the community. If you want to stop transmission in the community, you have to probably reach 50% of the population or more to really reduce the amount of virus circulating. So it will take some time before we get there. Even if a vaccine is available, there will be people who will want to wait a little longer to see how things are with the vaccine before they are ready to take it.
Q: I have a few questions about how vaccines work. If you already have antibodies, does this affect your body’s response to the vaccine?
A: If you’ve been exposed before, this shouldn’t affect a vaccine’s potential to give you even better immunity than you received with a natural infection. The clinical trials that have been done, most of them – to my knowledge – haven’t ruled out people who have had covid infections in the past. And I don’t think anyone has told us that we are going to deny the vaccine to people who have already had covid. There are several reasons for this. The first is that there is a lot of variability in the antibody levels that we can measure after a person has had a covid. And so you don’t know if that level of antibody, for that person, is going to be protective, unless you really step in and measure it. And even then, we still don’t have a clear idea of what level you need to be. And the second thing is that we know with other coronaviruses that you can have protection against re-infection for a while, but then that protection wears out or wears off over time. And third, we also know that, in many cases, vaccines will provide longer lasting protection than natural infection.
Q: There will be several vaccines there. Should a person take more than one?
A: In general, no, you should not take more than one vaccine against a pathogen or virus. When these vaccines are deployed, some require two doses. And you will want to take the second dose of the same vaccine that you took the first dose. This is not to say that it will not be possible in the future to take a different vaccine as a second dose, but we need to collect data on whether you will achieve similar levels of protection or better if you mix and match. .
Q: If you have been exposed before, does it increase your risk of having an autoimmune reaction when you receive the vaccine?
A: We haven’t seen any evidence of this yet. The concept is called disease improvement. It’s this idea that if you’re exposed to a virus or potentially a vaccine once, and you get a less than complete immune response – like a partial immune response – the next time you’re infected, and you’re in. exposed to a virus, you may have a more severe form of the disease for the reason you mentioned: an overactive immune system. This happens in dengue fever. This is a theoretical possibility with this vaccine. But everything indicates that it won’t be a problem, based on what we’ve seen so far.
Q: Is there anything you can see from your perspective in the vaccine rollout that we should be keeping an eye on? Bumps in the road you anticipate?
A: It’s going to be very complex. Each state is going to have its own system for doing this. So I expect there will be a hiccup in the process. I think every state is hopefully doing the planning it needs to do. But we’ve never done anything like this before, where you’re trying to roll out so many vaccines to so many people in such a short time.
The other is that the cold chain requirements for mRNA vaccines are different from other vaccines. So we need to have freezers throughout the supply chain, rather than refrigerators, which people are more used to. Then there is the matter of making sure that people take the second dose of the same vaccine, when they are supposed to. And it will be very important to have a reliable system to ensure that this will happen. Hopefully states will have systems to make sure whoever is in the priority group actually gets the vaccine rather than getting it to people who aren’t really supposed to get it early.
And then I think it will be very important for everyone in the world to watch out for any side effects after people get vaccinated. We think this probably won’t be a problem, but we need to watch it just in case. Given the number of people who have received these vaccines so far, I doubt that this would be anything that would really change the way people think about vaccination. But we also want to maintain confidence in vaccines. And so we have to be really transparent about these things.
Q: At this point about transparency and trust: is there anything we’ve learned so far in this pandemic about building trust between health agencies and ordinary people who need to act? Do you like downloading a contact tracing app or getting a vaccination?