Becker's Clinical Quality & Infection Control

10 INFECTION CONTROL Nasal COVID-19 vaccines may make better boosters, experts say By Erica Carbajal N asal vaccines may serve better as a COVID-19 booster than current shots because they offer protection in the mucosal linings of the airway, where the coronavirus first lands, e New York Times reported Feb. 2. Injected vaccines produce antibodies in the blood, few of which make it to the nose — the virus' entryway. is, in part, is why so many people who received their booster dose became infected amid the highly-trans- missible omicron surge. Instead, some experts' thoughts behind why mucosal vaccines may be ideal as boost- ers is because they coat the airways with long-lasting antibodies, and thus are better at preventing infection altogether, not just protecting from severe illness. "It is the difference between planting sentries at the gates to bar intruders and trying to oust them aer they had already stormed the castle," writes author Apoorva Mandavilli. An immunologist at the University of Toronto, Jennifer Gommerman, PhD, told the Times nasal vaccines are "the only way to really circumvent person-to-person transmis- sion," adding, "We can't live forever sheltering vulnerable people and boosting them so that their antibody levels stay artificially high." e news outlet also cited a preprint study that found a nasal vaccine administered as a booster triggered immune memory cells and antibodies in the nose and throat and ramped up protection from initial vaccination. "Our approach is to not use a nasal vaccine as a primary vaccination, but to boost with nasal vaccine, because then you can leverage the existing immunity that's already created," said Akiko Iwasaki, PhD, an immunologist at New Haven, Conn.-based Yale University who led the study. An additional benefit to nasal vaccines is they would streamline the process of immunizing large populations, as they are less time-consuming and require less skill to administer, experts told the Times. Currently there are at least a dozen nasal COVID-19 vaccines in development globally. n White-tailed deer becoming virus reservoir 'a top concern right now,' CDC official says By Erica Carbajal W hite-tailed deer are easily infected by the coronavirus, with some experts now concerned they may become a reservoir for the virus to mutate and spread, The New York Times reported Feb. 7. The virus has spread among other species, such as mink and big cats. White-tailed deer — of which there are 30 million in the continental U.S. — becoming a reservoir for the virus is particu- larly concerning both because of how closely they live along- side people and their large population. If the virus were to become widespread among the species, it could open up new chances for the pathogen to mutate and spread to other animals, or back to humans in the form of a new variant. "This is a top concern right now for the U.S.," said Casey Barton Behravesh, who directs the CDC's One Health Office, which fo- cuses on connections among human, animal and environmental health. "If deer were to become established as a North American wildlife reservoir — and we do think they're at risk of that — there are real concerns for the health of other wildlife species, livestock, pets and even people," she told the Times. Scientists are still exploring a number of questions regarding the virus's spread among deer, such as how deer contract the virus, how the pathogen might mutate inside the host, and whether deer could pass the virus back to humans. n New York City's COVID-19 mystery By Mackenzie Bean S cientists in New York City have repeatedly de- tected "cryptic lineages" of the coronavirus in wastewater samples for the past year, The New York Times reported Feb. 3. Researchers first identified the viral fragments in the city's wastewater last January, according to findings published Feb. 3 in Nature Communica- tions. The lineages have a unique mix of mutations never before seen in humans, suggesting the presence of a new variant. The lineages have been circulating for at least a year without overtaking delta or omicron as the na- tion's dominant strain, and there are no signs they pose a greater risk to human health, according to the Times. Researchers say the lineages' origins are still unclear. "At this point, what we can say is that we haven't found the cryptic lineages in human databases, and we have looked all over," study author Monica Trujillo, PhD, a microbiologist at New York City-based Queensborough Community College, told the Times. Researchers said it's possible these lineages come from humans with COVID-19 whose virus samples are not being genetically sequenced. Another hypothesis is that the lineages may stem from animals infected with the virus. n

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