Delta raises the stakes of being unvaccinated

With only about half of the nation's population — 163.3 million people — fully vaccinated against the coronavirus, public health experts are concerned that the vaccine's advantages could begin to erode. Photo by David 'Dee' Delgado/Reuters The delta variant is fueling COVID-19 outbreaks across the nation, particularly in undervaccinated communities. The Centers for Disease Control and Prevention announced this week that people infected with delta carry a large amount of virus — regardless of their vaccination status — which means fully vaccinated people can, in rare cases, transmit it to other people. That wasn't a concern with prior dominant variants of the virus. Dr. Anthony Fauci, the nation's top infectious disease expert, told the PBS NewsHour that fully vaccinated people are still protected against severe disease and death. But the fact that the delta variant makes it possible for them to infect unvaccinated people means the nation needs to reinstate more prevention measures.  That's why the CDC reversed course on its mask guidance this week. Now, fully vaccinated people who live in places where viral transmission is high are advised to once again wear masks indoors. CDC director Dr. Rochelle Walensky also recommended that teachers, staff and students in K-12 schools should mask up, even if they're fully vaccinated.  But vaccination is still the best tool we have when it comes to keeping the pandemic under control. President Joe Biden announced this week that millions of federal workers will need to sign paperwork confirming that they've been vaccinated or comply with requirements like masking, distancing and weekly testing if they continue to refuse vaccination. These new rules also serve as an example for private employers who want to further incentivize that their employees get vaccinated, according to the Associated Press.  Although it's possible for fully vaccinated people to develop "breakthrough" coronavirus infections, that fact does not indicate that COVID-19 vaccines are failing. Experts say that variants like delta put additional pressure on vaccines. Variants can only emerge when a virus has ample opportunity to circulate. When Americans refuse to get them, or people in countries that don't have access to vaccines aren't able to, it's more likely that the virus will mutate in ways that allow it to transmit more easily, or even evade our immune systems.     But how exactly does delta's unique mutations give it such an advantage? For starters, the variant is able to spread about twice as fast as those that came before it. Its incubation period is four days instead of six, meaning that infected people become contagious sooner, according to Kaiser Health News. Experts expect that delta will continue to send case counts skyrocketing in the U.S. But death rates are unlikely to be as devastating as they were before vaccines were available, given that around half of the population is fully vaccinated. One of the more significant stories of the Tokyo Games is not only who's winning medals, but why one of the biggest names in sports decided to step back. Gymnast Simone Biles said it was concern for her own mental well-being that led her to do so. Her decision quickly sparked larger conversations around mental health, athletics and race. Wildfires in the West are increasing health risks faced by residents of already polluted regions of the U.S. That includes communities like the ones in California's San Joaquin Valley, which is surrounded by mountains that restrict air movement and cause a concentration of particle pollution. Mounting research suggests that wildfire smoke can increase the severity of respiratory issues, as well as the possibility of heart attacks and strokes among vulnerable people.  This summer has been marked by a series of intense heat waves, including one in the Pacific Northwest that's estimated to have taken hundreds of lives. Experts say that at the current rate of global warming, "record-shattering heat" is expected to occur with more frequency over the next few decades. Just as climate change increases the probability of these events, data suggests that their likelihood would decrease if fossil fuel emissions fall, according to The Conversation. But if the global community fails to reduce those emissions, no single region will be exempt from the threat of extreme heat. Ask the science desk: "Ask the science desk" is off this week, but remember to send us your burning science questions — pandemic related or otherwise — at sciencedesk@newshour.org   What we're reading, watching and listening to this week: Climate activists target a retrofitted 'peaker plant' in Queens, decrying new fossil fuel infrastructure. (Inside Climate News) "They say burning natural gas harms communities of color, exceeds New York's carbon limits and helps make the case for a federal clean energy standard." Noise pollution affects practically everything, even seagrass. (Hakai Magazine)  "Seagrass may not have ears, but that doesn't stop noise pollution from causing serious damage to the plant's other structures." How bird brains thrived during a mass extinction. (Popular Science) "A remarkably preserved skull from a small, gull-like creature called Ichthyornis may shed light on how the ancestors of modern birds weathered the mass extinction that killed off all the other dinosaurs." Meet the woman restoring Native American peaches to the Southwest. (Atlas Obscura)  "Searching for the precious trees has become Reagan Wytsalucy's calling." Underground 'lakes' on Mars may just be big globs of clay. (Gizmodo)  "Recent detections of something that looked like liquid water could be chalked up to an esoteric mineral, according to new research." How yellowcake shaped the West. (High Country News) "The ghosts of the uranium boom continue to haunt the land, water and people." Until next time,  Bella Isaacs-Thomas Megan McGrew News assistant on the PBS NewsHour's science desk Was this email forwarded to you? 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