Becker's Clinical Quality & Infection Control

10 INFECTION CONTROL Vaccine makers bet on mRNA technology to improve future flu shots By Erica Carbajal V accine makers are leading studies us- ing mRNA technology, which made the rapid development of COVID-19 vaccines possible, in hopes of creating more effective flu shots in the future, e New York Times reported Oct. 9. Each year there are between 3 million and 5 million cases of severe illness from the flu worldwide, with up to 650,000 deaths. Flu shots are generally good for one influenza season, with effectiveness ranging between 40 percent and 60 percent, according to the Times. Still, in the 2018-19 flu season, when the shot had an effectiveness of just 29 percent, it prevented an estimated 4.4 million cases in the U.S., as well as 58,000 hospitalizations and 3,500 deaths, according to a study cited by the Times. Five more notes on mRNA technology and flu vaccines: 1. Traditional influenza shots take a while to produce and typically protect against four anticipated strains. ey are grown for months in chicken eggs, and since it's a slower process, scientists must select which strains to include several months before flu season, oen leading to a mismatch by the time the actual strain arrives. Essentially, "It's an educated guessing game," Alicia Widge, MD, an immunologist at the National Insti- tutes of Health's Vaccine Research Center, told the Times. "We're always catching up with the virus." 2. In contrast, mRNA vaccines are manufac- tured relatively quickly, potentially allowing scientists to better match the shots to each season's flu strains. Researchers hope eventu- ally the technology can be altered to make the flu shots work for a wider range of flu strains or to develop a universal flu vaccine that offers protection for several years. 3. Several vaccine makers, including Mod- erna and Pfizer, started trials for mRNA flu vaccines this summer. 4. e technology could also enable vaccine makers to create combination shots more easily. In September, Moderna shared re- sults from an experiment that showed com- bining mRNAs for seasonal flu, COVID-19 and respiratory syncytial virus produced high levels of antibodies for all three viruses in mice. 5. If studies currently underway show mRNA flu shots improve effectiveness, it would still likely take years to gain approval because trials for the shots don't have the government support that COVID-19 vac- cines did. Federal regulators would also not consider them for emergency authorization, given the flu isn't a novel threat and there are existing vaccines. n It's time to upgrade from cloth masks, experts say By Cailey Gleeson M isinformation surrounding masking has turned the topic into a binary for Americans: either you're masked or not — but experts say the public needs to start paying attention to the quality of their masks. In an Oct. 4 piece for The Atlantic, science editor Yasmin Tayag cited a study from Bangladesh linking surgical masks to an 11.2 percent decrease in COVID-19 symp- toms and antibodies compared to a 5 percent decrease with cloth masks. Ms. Tayag recognized factors contributing to the "contin- ued obsession" with cloth masks — such as cost effective- ness and eco-friendliness — and added that public health agencies should have used government resources to combat the shortage. Linsey Marr, PhD, an airborne virus expert at Virginia Tech in Blacksburg, told Scientific American in a Sept. 30 piece that disposable masks may actually be worn until they become "visibly damaged or soiled." The Scientific American piece went on to say, contrary to the start of the pandemic, there is now a "cornucopia" of high-filtration respirator-style masks. The most important considerations for mask effectiveness are filtration, fit and comfort. An issue with high filtration masks being commercially available, according to Scientific American, is the reliabil- ity of suppliers. Kimberly Prather, PhD, an atmospheric chemist and professor at the University of California San Diego, recommended the suppliers Project N95, Bona Fide Masks and DemeTech. "Even if a pivot toward surgical masks wouldn't be some pandemic panacea, America's mask inertia is in many ways a symptom of the nation's single-pronged pandemic response," Ms. Tayag wrote. "The country has collectively banked on vaccination to end the pandemic, and one consequence is that attention to other protective mea- sures has lagged." n

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