Welcome to covered quickly. Scientific american podcast series. This is your fast track update on the kobe. Pandemic we bring you up to speed on the science behind most urgent questions about the virus and the disease we demystify the research and help you understand what it really means. I'm tanya lewis. I'm josh fishman. Scientific american senior health editors today. We'll explain why the cdc now wants vaccinated people to wear masks indoors again and we'll discuss one big reason why some people still refuse to get vaccinated. Just a few months ago. The cdc said vaccinated. People didn't have to wear masks in most settings but this week the agency reversed course saying vaccinated. People should wear masks at times. What do the recommendations actually say tania and why the sudden shift in position so in its latest guidance the c. d. c. says vaccinated people should once again wear masks in public indoor settings under certain circumstances for example if you live in an area with high levels of kobe transmission which includes people who live in places with more than fifty cases per one hundred thousand people in the last week the agency also recommended universal. Masking all k. Through twelve schools including all students teachers and staff. The cdc says the reason for the shift is new data about the delta variant and breakthrough infections. Delta's known to be much more transmissible than previous strains and appears to produce about a thousand times as much virus in the body as the original strain there have been reports of breakthrough infections among fully vaccinated people and in rare cases they may be able to transmit it to others so the reason behind vaccinated people wearing masks is to prevent them from transmitting the virus people who cannot get vaccinated such as children under twelve. Or those who are immuno-compromised breakthrough infections are expected as no vaccine is one hundred percent effective and they may be more common than we thought with the delta variant according to data from the uk in israel the vaccines are still extremely good at preventing severe disease and death. The vast majority of those hospitalized with kobe right now are unvaccinated. If you're vaccinated and you get co bid it doesn't mean the vaccine didn't work as former surgeon general jerome atoms. Put it in a tweet. Think of the virus like the ocean the vaccine like a life vest. You may still get wet but your life vest vaccine significantly lessens. The chance you'll drown and getting wet doesn't mean the life vest didn't work over the past. Several weeks cases deaths in hospitalizations. All been rising in the us. We have defenses against the disease but some people won't use them. Vaccinations have stalled and some unvaccinated people. Still refuse to wear masks. Most of us are baffled by all this. Why are people so resistant josh. I think there are lots of reasons. But there's one big one. Many people still do not think. Kovic is a serious and deadly disease. There are two factors that contribute to this one has to do with numbers. The other has to do with who we listened to. Let's look at the numbers. I we have three hundred thirty million people in this country. Cdc data shows that during the eighteen months of the pandemic two point three million have been admitted to the hospital and indication of serious illness. Now imagine a bowl of three hundred million marbles and then drop into million more. They'd be hard to spot so there's a good chance that out of hundreds of millions of americans. Somebody might not know another person who's had a severe kobe. 'bout it's easier to dismiss it as a mile illness. If severe disease is not part of your personal experience and that appears to be what. Unvaccinated people believe in june the kaiser family foundation polled people about getting the vaccine fifty seven percent of unvaccinated. Adults said. what's in the news about. Kovic is generally exaggerated only twenty two percent of vaccinated adult say this and seventy one percent of unvaccinated adults. Say they're not at all worried or not too worried about getting sick from the virus. That's pretty mind boggling. Who are taking their kids from that. Belief has been reinforced by lot of people over the past year and a half. Who have said that cove isn't serious. Psychologist robert shell dini of arizona. State university studies how people form beliefs and what influences them. So he and. I talked about this. People pay a lot of attention to what others around them. Friends family neighbors political leaders. Say or do shall dini says if others who share your values have a particular attitude that makes it more legit. The local patterns of low vaccine rates certain counties in alabama or missouri for instance are examples of neighbors influencing neighbors. In this way. Then there are the big national influencers. We all heard donald trump. Say that cova does not a big deal no worse than the flu. A lot of republican congress people governors railed against mask wearing and refused to wear masks. Themselves shall points out. These leaders were sewing uncertainty and uncertainty about what to do amplify their social influence. Now we're seeing the results as deaths in hospitalizations race higher and higher among unvaccinated. People but attitudes can change shall dini says social disapproval changes them not yelling or finger-pointing but if local leaders say that shunning vaccines hurts the community and hurts people themselves that can be surprisingly effective these notions ripple around neighborhoods the vaccines. He hopes will follow those ripples..