{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,23]],"date-time":"2026-03-23T18:33:58Z","timestamp":1774290838191,"version":"3.50.1"},"reference-count":52,"publisher":"Public Library of Science (PLoS)","issue":"3","license":[{"start":{"date-parts":[[2026,3,23]],"date-time":"2026-03-23T00:00:00Z","timestamp":1774224000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:sec id=\"sec001\">\n                    <jats:title>Objectives<\/jats:title>\n                    <jats:p>This study aimed to assess the dissemination of anti-science messages regarding COVID-19 in Brazil, specifically examining how social inequalities contributed to the misconception that chloroquine has a protective effect against the virus.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec002\">\n                    <jats:title>Study design<\/jats:title>\n                    <jats:p>Three countrywide population-based studies were conducted in 2020 (May 14\u201321, June 4\u20137, and June 21\u201324), including 133 Brazilian cities (N\u2009=\u200974,077).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec003\">\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Participants (\u226520 years old) were asked whether they believed in chloroquine\u2019s protective effect against infection with the SARS-CoV-2 virus (no\/yes\/don\u2019t know). \u201cYes\u201d and \u201cdon\u2019t know\u201d answers were considered misconceptions (effect of denialism). A jeopardy index score was calculated to assess cumulative social deprivation based on sex, race and ethnicity, and socioeconomic variables. Descriptive analysis and inequality measures (Slope Index of Inequality \u2013 SII; and Concentration Index) were used to evaluate the association between believing in chloroquine\u2019s protective effect against COVID-19 and the jeopardy index. Multinomial logistic regression was used in the unadjusted and multivariable analysis.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec004\">\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Overall, 47.6% of participants either believed that chloroquine prevented COVID-19 or stated, \u201cI don\u2019t know.\u201d Marginalized racial and ethnicity groups, those with low education level, and those with low socioeconomic status were more likely to erroneously believe that chloroquine prevented COVID-19. The chance of lack of knowledge (Don\u2019t know) was higher (Odds Ratio: 2.57,CI95% 2.21; 2.99) among women, Black\/Brown\/East Asian\/Indigenous, and among those in the lowest education level and wealth quartiles compared to men, white individuals, and those in the highest education and wealth quartiles. Absolute and relative inequalities were observed according to the jeopardy index. The highest absolute inequality was observed for the category \u201cI don\u2019t know\u201d (SII\u2009=\u2009\u221215.1).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec005\">\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Misbelief in chloroquine\u2019s protective effect against SARS-CoV-2 was high in Brazil. People with greater social vulnerability were more likely to wrongly believe that chloroquine prevented COVID-19.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1371\/journal.pone.0341666","type":"journal-article","created":{"date-parts":[[2026,3,23]],"date-time":"2026-03-23T17:45:57Z","timestamp":1774287957000},"page":"e0341666","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["Social inequalities in the misbelief of chloroquine\u2019s protective effect against COVID-19: results from the EPICOVID-19 study in Brazil"],"prefix":"10.1371","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4496-4122","authenticated-orcid":true,"given":"Bruno 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