
Q & A With Dr. Naor Bar-Zeev
When will we have a vaccine for COVID-19? How effective will it be? Naor Bar-Zeev, an associate professor of international health and vaccine science and deputy director of the International Vaccine Access Center at the Johns Hopkins Bloomberg School of Public Health and a pediatric infectious disease physician and statistical epidemiologist, spoke about vaccine development and the country’s response to the pandemic. This interview has been condensed.
What are your thoughts on the states’ response to safety concerns?
It’s difficult to tell one is right and one is wrong. States are doing the best they can to optimize the response. The critical issue is contact tracking, tracing and isolation. And for the public, they need to be wearing masks when out.
What have you learned about a possible vaccine?
I’m not doing any direct work with development. I work on distribution once it is available. Once the vaccine is available there will be an issue of making it available in large enough numbers to vaccinate everybody. There will be a high level of manufacturing [but] if we wait until [enough are ready] we will lose even more people.
We’ll be lucky if we have 2 billion doses by the end of 2021. Countries will have to sort how to distribute it and once that decision is made, decide on individual locations. And then they have to decide a good mechanism of delivery to children, or what about high-risk communities?
They will have to be engaged in the discussion, too. The vaccine has to be safe for the community. Whether that means making it available to shuls or schools or the local town hall. Logistically, we don’t want people congregating.
Whether it’s possible or feasible is one thing, but the ideal would be a shot delivered in the mail. But we’re not quite there. We have to design delivery with the communities.
We have to make sure the vaccine is safe itself, too, and test the surveillance of that [to keep an eye on results]. And it will have to be adaptive to where the hot spots [of breakouts] are.
At the soonest, when do you predict a vaccine will be available to the U.S. population?
We have [vaccines], but they just need to be proven effective. That means a wide trial with all ages. Then it goes through licensing after all the data is collected. Then it can be manufactured. Realistically, it is hard to pinpoint, but it is unlikely that you can get one by the end of 2020. Maybe, for health care workers, by 2021.
Do you believe there will have to be a difference in dosages for older adults?
The main issue is that older adults have the most responsive immune system. What is generally not safe may be needed to be effective for older adults. It would be wonderful to have one vaccine, but it’s possible we will need different ones for older adults, or more frequent dosages.
We also don’t know how long the vaccine’s effect could last, and if that could be different for different ages. If it wanes and we’re back to where we started, that would be no good.
How reliable are the current tests on chimpanzees for predicting whether it will work on humans?
It is a necessary step. If it’s safe to one animal similar to humans, meaning primates, it’s a good indication to move it to human trials. Then we need to demonstrate on humans that it’s safe and efficacious. The more it’s evaluated, the more I will be comfortable to say it’s safe.
There’s only been 1,500 people vaccinated so far. We need many more people before I can say something is safe. So we’ll increase the number again soon; the next trials will vaccinate 30,000 each.
The worst thing is if [we went straight to testing on] people to cut corners and that causes harm. That would be terrible for all vaccines, because people’s trust in vaccines would go down.
What will that next phase of testing look like?
So we break it into Phase 1, 2 and 3. Before Phase 1 of human trials, you have a whole bunch of experiments, then to animal testing.
We haven’t seen the results of Phase 2 yet, but are expecting to move to 3 soon. At the end of Phase 3, we can roll out the vaccines and begin a Phase 4. But when we get there, it also raises an ethical concern: What if the vaccine kills one in a million? Would you still give it to children?
These are not black and white questions, but there is a lot to consider.
What other challenges and questions like that must we consider?
So I already told you about distribution: who will get it first and how do we distribute it. Equity means everyone will be protected equally.
But also, what if we have 1 million doses and people over age 50 require two? And how are we affording it? And what if 70 percent is efficacious, or even just 50 percent? Do we still spend the money on it?
And what if there is no other option for a long time? The Rotary [International] vaccine in the ‘90s caused a condition in children, but it took 10 years for a new vaccine to come around.You have these questions of what is practical versus the specifics of it.
Above all, though, people must remember: A vaccine is not the be all or end all. It won’t make coronavirus go away. Obviously, we still need a vaccine. But, really, the idea of social distancing, washing your hands, being careful — this will still be crucial.
Carolyn Conte is a reporter for the Baltimore Jewish Times, an affiliated publication of Washington Jewish Week.