The possibility seemed real enough to announce publicly.
Em março de 2021, Florianópolis se viu diante de uma pergunta incomum: poderia uma vacina centenária contra sarampo, caxumba e rubéola oferecer alguma proteção contra um vírus inteiramente novo? O prefeito Gean Loureiro, munido de dados preliminares da UFSC apontando 76% de eficácia contra hospitalização por COVID-19, anunciou publicamente a possibilidade — mas com a prudência de quem sabe que esperança e evidência não são a mesma coisa. A cena captura um momento singular da pandemia: a urgência que empurra as cidades a explorar o improvável, temperada pela exigência de que a ciência confirme o que os números sugerem.
- Com hospitais sob pressão e vacinas específicas ainda escassas, Florianópolis considerou usar a tríplice viral — já disponível e com perfil de segurança consolidado — como escudo provisório contra a COVID-19.
- Pesquisadores da UFSC apresentaram ao prefeito dados preliminares sugerindo 76% de eficácia contra hospitalização e 42% contra sintomas, além de redução da carga viral em infectados.
- Um estudo americano publicado na mBio reforçou a hipótese, indicando que vacinados com MMR com menos de 42 anos desenvolveram formas mais leves da doença — o que pode explicar por que crianças, rotineiramente vacinadas, raramente adoecem com gravidade.
- O microbiologista David Hurley, da Universidade da Geórgia, celebrou o potencial da descoberta, mas alertou: era o primeiro estudo imunológico do tipo, e os dados ainda eram sugestivos, não conclusivos.
- Loureiro anunciou que aguardaria a publicação formal e a revisão por pares antes de qualquer decisão — um equilíbrio entre a pressão para agir e a responsabilidade de não agir sem base sólida.
Em março de 2021, o prefeito de Florianópolis, Gean Loureiro, tornou pública uma ideia incomum: usar a vacina tríplice viral — a mesma que protege contra sarampo, caxumba e rubéola desde a infância — como ferramenta contra a COVID-19. A proposta nasceu de pesquisas preliminares conduzidas por professores da Universidade Federal de Santa Catarina, que apontavam 76% de eficácia contra hospitalização e 42% contra infecção sintomática, além de redução da carga viral em pacientes infectados. Loureiro foi cauteloso: qualquer estratégia de vacinação para adultos não prioritários dependeria da publicação formal do estudo e de sua aprovação pela equipe técnica municipal.
A hipótese não era inteiramente nova. Meses antes, pesquisadores americanos haviam publicado na mBio resultados semelhantes, analisando oitenta pessoas divididas entre vacinadas com MMR e portadoras de imunidade natural. O achado central: vacinados com menos de 42 anos que contraíram COVID-19 apresentaram quadros mais leves. Isso oferecia uma possível explicação para um enigma da pandemia — por que crianças, que recebem a tríplice viral nos primeiros anos de vida, raramente desenvolvem formas graves da doença.
David Hurley, microbiologista da Universidade da Geórgia e coautor do estudo americano, reconheceu o potencial da descoberta, mas fez questão de sublinhar seus limites: era o primeiro trabalho imunológico a investigar essa relação, e os dados, embora promissores, ainda precisavam de confirmação. De volta a Florianópolis, o prefeito ecoou essa mesma postura — entusiasmado o suficiente para anunciar, prudente o suficiente para esperar. O momento retratava com precisão o espírito daquela fase da pandemia: a disposição para explorar o improvável, contida pela exigência irrenunciável de rigor científico.
In early March 2021, the mayor of Florianópolis floated an unconventional idea: what if the city used the MMR vaccine—the standard three-in-one shot that protects against measles, mumps, and rubella—as a potential tool against COVID-19? Gean Loureiro, the city's chief executive, had been presented with preliminary research from a group of professors at the Federal University of Santa Catarina suggesting the vaccine might offer protection against the novel coronavirus. The results, he said, were encouraging enough to warrant serious consideration.
According to Loureiro's account of the research, the MMR vaccine showed a 76 percent effectiveness rate in preventing hospitalization from COVID-19 and a 42 percent rate against symptomatic infection. Beyond those numbers, the vaccine appeared to reduce viral load in infected individuals. The mayor's proposal was measured: use the vaccine in non-priority groups of adults over eighteen, pending further validation. He acknowledged the obvious caveat—the research needed to be formally published, subjected to peer review, and analyzed by his technical team before any decision could be made. Still, the possibility seemed real enough to announce publicly.
The Florianópolis inquiry was not entirely isolated. Months earlier, in February, researchers publishing in mBio, a journal of the American Society for Microbiology, had reported similar findings. They studied eighty people divided into two groups: fifty who had received the MMR vaccine and carried antibodies from it, and thirty who had natural immunity from having contracted measles, mumps, or rubella in the past. The researchers found that vaccinated individuals under the age of forty-two who contracted COVID-19 experienced milder disease than their unvaccinated counterparts.
The American findings offered a potential explanation for a pattern that had puzzled epidemiologists since the pandemic began: children, who routinely receive the MMR vaccine in their first years of life, were far less likely to develop severe COVID-19 than adults, and their mortality rates were substantially lower. Most children receive their first MMR dose between twelve and fifteen months of age, with a second dose between four and six years old. If the vaccine conferred some cross-protective benefit against COVID-19, it would help account for the stark age gradient in disease severity.
David J. Hurley, a molecular microbiologist at the University of Georgia and one of the study's authors, emphasized both the promise and the caution warranted by the findings. The MMR vaccine was already known to be safe, with minimal side effects. If it also offered protection against COVID-19—reducing infection rates, transmission, and disease severity—then widespread vaccination would be justified on multiple grounds. But Hurley was careful to note that this was the first immunological study to examine the relationship between the vaccine and the coronavirus. The evidence was preliminary, suggestive, not conclusive.
Back in Florianópolis, Loureiro's public statement reflected that same balance. He congratulated the UFSC researchers and committed to waiting for the official publication of their work and peer review before moving forward. If the analysis proved positive, the city would develop a vaccination strategy for the coming weeks. The moment captured a particular phase of the pandemic: desperate enough for cities to consider unconventional approaches, but cautious enough to insist on scientific rigor before implementation. The question now was whether the peer-reviewed evidence would support what the preliminary data seemed to promise.
Citações Notáveis
Our technical team is analyzing the research. There is a real possibility we could use it.— Mayor Gean Loureiro
If the vaccine has the added benefit of preventing COVID-19, disease spread, and severity, vaccination is well worth it.— David J. Hurley, molecular microbiologist, University of Georgia
A Conversa do Hearth Outra perspectiva sobre a história
Why would a city mayor be announcing vaccine strategy based on research that hasn't been peer-reviewed yet?
Because by March 2021, people were exhausted and grasping for any tool that might work. The preliminary results looked promising enough that it seemed worth saying out loud—but Loureiro was careful to say he'd wait for peer review before actually doing anything.
The MMR vaccine protects against three diseases that have nothing to do with COVID. How would it help with a respiratory virus?
That's the mystery the researchers were trying to solve. They noticed vaccinated people under 42 had milder COVID symptoms. The theory is that the vaccine trains your immune system in a way that provides some cross-protection—a kind of general boost to your defenses, not specific to COVID.
But 76 percent efficacy against hospitalization sounds remarkable. Why isn't this being used everywhere?
Because those numbers came from a small study of eighty people, and the researchers themselves said it was the first of its kind. Remarkable preliminary results often don't hold up under scrutiny. That's why peer review matters—and why Loureiro said he'd wait for it.
What about the 42 percent figure against symptoms? That's much lower.
Right. So even if the hospitalization number holds, you're looking at a vaccine that might prevent severe disease but wouldn't stop people from getting infected or having mild symptoms. That's useful, but it's not a replacement for a COVID vaccine.
The article mentions children have lower mortality rates. Is that because of MMR vaccination?
That's what the researchers were suggesting—that routine childhood MMR vaccination might partially explain why kids fare better with COVID. But that's still a hypothesis. The pattern exists; the mechanism isn't proven.