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Novavax reports that its two-dose protein-based vaccine against COVID-19 has been 100% effective in preventing severe illness, hospitalization and death due to COVID-19, as well as 90.4% effective against COVID-19 symptoms in large-scale human studies. These studies, which involved thousands of people in the U.S. and Mexico, showed that the vaccine also was highly effective against “Alpha,” the SARS-CoV-2 variant first identified in Great Britain, reports Carl Zimmer at The New York Times (6/14/21). “Novavax plans to apply for authorization in UK, EU, India, South Korea, and possibly the U.S.,” according to an Unbiased SciPod post (6/15/21).

A 6/17/21 story by Tanya Lewis at Scientific American describes some of the incentives being offered to people for getting vaccinated against COVID-19 — including lottery tickets, college scholarships, train tickets, firearms, cash pay-outs, cannabis joints, doughnuts, free trips, cruises, and gift certificates. “Public health experts use incentives all the time to get people to quit smoking, exercise more, and so on,” the story describes the director of the Health Decision Sciences Center at Massachusetts General Hospital’s general medicine division as saying. An unpublished study by the Mass General researcher suggests that incentives might effectively induce people to get a COVID-19 vaccine, Lewis reports. But for some people the best inducement is an opportunity to stop wearing a mask and a general return to normalcy, the story suggests.

Some positive news for people who have transplanted organs and thus take immune-suppressing drugs: a third dose of a mRNA vaccine against COVID-19 provoked a stronger immune response, at least in the form of antibodies, in organ transplant patients than the standard two doses did, per various reports. The findings, from a small study of patients who received a third dose this spring, were published 6/15/21 in Annals of Internal Medicine. The findings are “part of a broader discussion about whether and when to offer extra doses to vulnerable individuals,” writes Jennifer Couzin-Frankel at Science (6/14/21). In past studies, organ transplant patients who got a two-dose COVID-19 vaccine were far less likely to make protective antibodies against SARS-CoV-2 than the general population was. Some larger three-dose studies among people with compromised immune systems are under way, Couzin-Frankel reports. A medical oncologist at the University of Pennsylvania is not very worried about the effectiveness of COVID-19 vaccines among people with cancer, the story states. The story then describes two recent studies of cancer patients showing that they produced antibodies against SARS-CoV-2 after receiving a COVID-19 vaccine. However, a third study found much lower antibody levels among vaccinated cancer patients than it did among their healthy family members who also were vaccinated, Couzin-Frankel reports.

The Unbiased SciPod posted some helpful informational graphics about Pfizer’s ongoing studies of its COVID-19 vaccine in children under 12 (6/11/21). The post states that dosages have been set based on initial smaller studies in children (one-third the adult dose for ages 5-11 and one-tenth the adult dose for ages 6 months to 5 years), and that researchers will enroll 4,500 children across 90 sites globally for the larger safety and effectiveness studies. “Children have immune system components that are more potent compared to adults. They may not need as high a dose for protection. Age criteria are related to immune system development, not physical size,” the post states. The results will likely become available this fall for review by the U.S. Food and Drug Administration, with a first batch — from studies in children ages 5 to 11 — expected in early September, the post states.

Nearly one quarter of all people in the U.S. who were infected with SARS-CoV-2 last year, including 19% of those who never reported COVID-19 symptoms from their infection, had new medical problems within a month or more of recovering from the virus, according to a large study covered by Pam Belluck at The New York Times (6/15/21). Belluck writes: “Those affected were all ages, including children. Their most common new health problems were pain, including in nerves and muscles; breathing difficulties; high cholesterol; malaise and fatigue; and high blood pressure. Other issues included intestinal symptoms; migraines; skin problems; heart abnormalities; sleep disorders; and mental health conditions like anxiety and depression.” The study, conducted by non-profit organization FAIR Health and not formally reviewed by experts for flaws, involved evaluating electronic health-insurance records.

A 6/11/21 story by Emily Anthes at The New York Times runs down some evidence-based approaches that employers can take to reduce the risk of SARS-Cov-2 infections and other health problems as workers return to offices nationwide. Employers should flush unused taps and other plumbing to clear any metals or Legionella bacteria colonies that accumulated, the story states. Employers also should upgrade their ventilation and filtration systems, the story states. The goal is four to six air changes per hour, the story states, which is equivalent to completely refreshing air every 10 to 15 minutes in a room. Portable air purifiers or even “desktop level HEPA filters” can help. And continue to wash your hands routinely, for at least 20 seconds each time, advises a Northwestern University environmental microbiologist who is quoted in the story. Not solutions: desk shields (plexiglass barriers are a good idea in grocery stores though), foggers, fumigators, ionizers, ozone generators and other ‘air cleaning’ devices,’ the story states. In most non-medical or non-lab settings, wiping down surfaces with bleach solutions or disinfectant solutions or wipes does little to prevent SARS-CoV-2 transmission. Besides, inhaling these substances is harmful. “The no. 1 thing is to get vaccinated,” the story quotes Joseph Allen at the Harvard School of Public Health as saying.

A debate among scientists about whether SARS-CoV-2 spreads mainly by fallen respiratory droplets on surfaces that people touch or spreads in air hampered public health efforts to control the pandemic and to prevent deaths. The implications for this debate were crucial, as Megan Molteni at Wired writes (5/13/21) — officials need to know whether public-health messages should focus on hand washing or on masking and isolation or both, particularly before vaccines become available. The general debate is over, as you probably know — the virus is mostly spread in indoor air. But why did researchers disagree until recently? In part, it’s because the arguments against airborne SARS-CoV-2 all rested on an assumption that only particles smaller than 5 microns could hang in the air; larger ones, aka droplets, fall to surfaces. But in reality, larger particles can stay afloat and behave like aerosols, many scientists and engineers have known, including aerosols expert Linsey Marr of Virginia Tech, Molteni and others have written. Molteni’s story masterfully traces the events, conversations, and research that came to expose the “fallacy of the 5-micron boundary.” The hero of this engaging story is Katie Randall, a graduate student who specializes in detective work to figure out how bits of knowledge are passed along through published research papers over time.

Guidance from the U.S. Centers for Disease Control in April stated that international and domestic travel are low-risk activities for people vaccinated against COVID-19 (so, this does not pertain, unfortunately, to U.S. children under 12, for whom COVID-19 vaccines are not yet authorized). In response to that update, Ceylan Yeginsu at The New York Times has written up answers to some of the questions that vaccinated travelers have these days (6/15/21). A summary of the answers (again, this information is all for vaccinated people in the U.S.): 1) Yes, you must still wear a mask at the airport and on flights; 2) No, you don’t have to quarantine or test if you travel domestically, unless it is required by a state or territory; 3) No, you don’t have to take a coronavirus test before departure to international destinations — not for the U.S. at least; check for your destination; 4) Yes, you have to test, even if vaccinated, three days before you return by air to the U.S.; 5) Check lists of countries that will accept people from the U.S. under certain conditions, including some destinations in Europe and the Caribbean.

Scientists at the Walter Reed Army Institute of Research in Maryland are working on a vaccine that could protect us against all coronaviruses. In this 6/9/21 podcast at Scientific American, Emily Mullins interviews Dr. Kayvon Modjarrad who is leading the effort at Walter Reed to develop a so-called universal coronavirus vaccine. The vaccine candidate that is being tested "combines nanoparticles from a blood protein called ferritin with coronavirus proteins.” (Sorry, I’m not sure what that means either.) Modjarrad says 200 different combinations of spike proteins (a type of complex molecules that are found on the surface of all coronaviruses), types of ferritin, and ways to link them eventually yielded a vaccine candidate that repeatedly provoked a strong immune response against SARS-CoV-1, SARS-CoV-2 and three of its variants in several species of animals ranging from rodents to sharks. The vaccine now is being tested in a small group of humans. “If it works and is safe, it could provide a foundation for a universal coronavirus vaccine,” Mullin says.

You might enjoy, “A lexicon for the late pandemic,” by Jay Martel for The New Yorker (6/14/21).