Show 1225: What Is the Evidence on Vaccines and Masks?

We have had eight months of COVID-19 pandemic, and there is nobody anywhere who isn’t ready for it to be over. That is why there is quite a bit of excitement about the potential for vaccines. Several have started phase 3 trials already. What does that mean and what can we expect?

Where Will We Get the Evidence on Vaccines?

During phase 3 trials, developers of a vaccine give it to lots of people. There is also a control group that gets no vaccine, but usually these people will get a placebo shot so neither the volunteers nor the researchers know who got which one. Once tens of thousands of people have been vaccinated and had a chance to encounter the coronavirus, scientists collect information on who got sick and whether there are serious adverse events from the vaccine itself.

All of that data must be carefully analyzed before a vaccine should be administered to the public. That’s also exactly the information any of us, including the vaccine hesitant, would need before agreeing to vaccination. The evidence on vaccines is not yet available, but it will be crucial to ending the pandemic.

How Can You Tell Which Masks Really Work?

A number of analyses of natural experiments have demonstrated that masks work to reduce COVID-19 spread dramatically IF 1) they are effective at stopping droplets and 2) everybody wears one. But how do you know if your mask stops droplets?

Scientists at Duke University devised a simple experiment utilizing laser light to visualize the droplets that escape a mask when a wearer is speaking. N95 masks are excellent–no surprises–but even homemade cloth masks can be surprisingly helpful. We talk with one of the researchers about the test and the findings.

Getting Away from Overkill:

Americans take an enormous number of pills. Some of them are helpful, but some are frankly unnecessary. Even after scientists collect the evidence on practices like treating fever in children, pediatricians and parents continue to give kids Tylenol or Advil to lower their temperature. In fact, fever can be helpful in overcoming an infection, so lowering it is often counterproductive.

What else are we doing wrong? Have you been admonished to finish every last antibiotic pill the doctor prescribed? Most of us have, but it isn't actually necessary. Dr. Paul Offit, author of Overkill: When Modern Medicine Goes Too Far, tells why. In addition, he gives us a summary of some common ways we overtreat conditions that don’t require treatment.

This Week's Guests:

Paul A. Offit, MD, is the Director of the Vaccine Education Center at the Children’s Hospital of Philadelphia as well as the Maurice R. Hilleman Professor of Vaccinology and a Professor of Pediatrics at the Perelman School of Medicine at the University of Pennsylvania.

Dr. Offit is the author of several books, including his most recent, Overkill, When Modern Medicine Goes Too Far. His website is http://paul-offit.com/about/  The photograph is of Dr. Offit.

Eric Westman, MD, MHS, is an associate professor of medicine and director of the Duke Keto Medicine Clinic in the Duke University Health System. His research on measuring mask effectiveness was published in Science Advances on August 7, 2020.