The race to tame COVID-19 has resulted in a wealth of research, new vaccines and treatments that hold out the promise of an end to the pandemic. But many questions remain.
Here, Max Nisen and Sam Fazeli, who cover health care and the pharmaceutical industry for Bloomberg Opinion and Bloomberg Intelligence, discuss some of the most pressing ones.
Do we really need a booster or third shot?
Fortunately, the vaccines that have been studied most — those from AstraZeneca, Pfizer-BioNTech and Moderna — continue to provide high protection against severe disease or hospitalization for at least six months after two doses. The question is whether the protection against severe disease will start to wane. I think we will see data from Israel on this, as well as from the U.S. Food and Drug Administration at its Sept. 17 meeting. Either way, it’s critical that we not oversell the potential benefits of a third shot.
How long should we wait to boost, and does it vary by vaccine or population?
The only way to truly answer this question is with big studies. But we don’t have time to do that. We should certainly consider third shots in at-risk people. But the definition of at-risk is rather arbitrary. It may be much easier — if you set aside supply and global equity issues — to just give a third shot at six or eight months to everyone over a certain age.
As of now, vaccines have been approved only for those 12 and older. What are the risks to young children, and when will shots be approved for them?
Children are often thought of as being at very low risk from COVID, but this is not exactly correct. A lot of our data is based on a period that involved home-schooling as well as social distancing and mask-wearing. The risk of long-term symptoms are real for children, and the number of kids in the hospital with COVID is increasing. On top of all this, we don’t know what happens to a child infected with both COVID and another respiratory disease. For all these reasons, it would be good to have vaccines available for children, but there needs to be a good deal of safety data before regulators will approve them.
Are there any safety concerns with boosters?
We don’t know for sure. Remember first that most, if not all, vaccine-induced side effects appear within the first two months of immunization, which is exactly what has happened with COVID-19 vaccines.
Will we need a fourth shot? Will it have to be tailored to specific variants?
It’s possible, but from what I understand about the science, it’s not likely unless we continue to worry about even mild infection levels as is the case right now. Current data suggests that boosting with existing vaccines develops strong antibodies against even evasive variants. But if a really troublesome variant arises, we could need another shot that specifically targets it.
How much should we worry about new mutants that are more deadly or evade vaccine efficacy? How can we avoid them?
You have to bear in mind that it’s not just the virus that evolves. Even without a third shot, the immune system matures over time. Normally, the more it sees an offending pathogen, the better it gets at responding to it. We don’t know whether the virus will become more or less deadly over time, however.
Have we learned any more about long COVID, and what’s the risk on that front for the vaccinated?
Yes, it’s being studied. Recent data found a 50 percent reduction in the risk of long COVID symptoms for vaccinated people. That leaves another group that does have symptoms, but we need more data to know how serious they are.
Are any new COVID treatments coming? Can they make a real difference?
Yes and yes; we already have highly effective monoclonal antibody therapies that significantly reduce the risk of developing severe disease in infected people, even those with a compromised immune system. We can also look forward to data for more convenient oral antiviral drugs that could also curb disease. Final-stage trial data is expected by the end of the year.
When will the pandemic be over?
At this point, it’s hard to avoid thinking that COVID will be an endemic virus like those that cause the common cold or flu — it will circulate for years to come. The end of the acute pandemic phase will come when vaccine and infection-driven immunity get to a point where the risk of bad outcomes is relatively low and we can stop focusing on case counts globally. The big swing factors are any further mutations and the speed with which vaccine supply is directed toward the developing world, where inoculation rates are lagging.