{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,3]],"date-time":"2026-11-03T22:29:53Z","timestamp":1793744993900,"version":"4.6.1"},"reference-count":43,"publisher":"eLife Sciences Publications, Ltd","license":[{"start":{"date-parts":[[2021,7,23]],"date-time":"2021-07-23T00:00:00Z","timestamp":1626998400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2021,7,23]],"date-time":"2021-07-23T00:00:00Z","timestamp":1626998400000},"content-version":"am","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2021,7,23]],"date-time":"2021-07-23T00:00:00Z","timestamp":1626998400000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000060","name":"National Institute of Allergy and Infectious Diseases","doi-asserted-by":"publisher","award":["R21AI126024"],"award-info":[{"award-number":["R21AI126024"]}],"id":[{"id":"10.13039\/100000060","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000060","name":"National Institute of Allergy and Infectious Diseases","doi-asserted-by":"publisher","award":["R01AI146849"],"award-info":[{"award-number":["R01AI146849"]}],"id":[{"id":"10.13039\/100000060","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["elifesciences.org"],"crossmark-restriction":false},"short-container-title":[],"abstract":"<jats:sec id=\"abs1\">\n                    <jats:title>Background:<\/jats:title>\n                    <jats:p>\n                      Asymptomatic\n                      <jats:italic>Plasmodium falciparum<\/jats:italic>\n                      infections are common in sub-Saharan Africa, but their effect on subsequent symptomaticity is incompletely understood.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"abs2\">\n                    <jats:title>Methods:<\/jats:title>\n                    <jats:p>\n                      In a 29-month cohort of 268 people in Western Kenya, we investigated the association between asymptomatic\n                      <jats:italic>P. falciparum<\/jats:italic>\n                      and subsequent symptomatic malaria with frailty Cox models.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"abs3\">\n                    <jats:title>Results:<\/jats:title>\n                    <jats:p>Compared to being uninfected, asymptomatic infections were associated with an increased 1 month likelihood of symptomatic malaria (adjusted hazard ratio [aHR]: 2.61, 95% CI: 2.05 to 3.33), and this association was modified by sex, with females (aHR: 3.71, 95% CI: 2.62 to 5.24) at higher risk for symptomaticity than males (aHR: 1.76, 95% CI: 1.24 to 2.50). This increased symptomatic malaria risk was observed for asymptomatic infections of all densities and in people of all ages. Long-term risk was attenuated but still present in children under age 5 (29-month aHR: 1.38, 95% CI: 1.05 to 1.81).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"abs4\">\n                    <jats:title>Conclusions:<\/jats:title>\n                    <jats:p>\n                      In this high-transmission setting, asymptomatic\n                      <jats:italic>P. falciparum<\/jats:italic>\n                      can be quickly followed by symptoms and may be targeted to reduce the incidence of symptomatic illness.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"abs5\">\n                    <jats:title>Funding:<\/jats:title>\n                    <jats:p>This work was supported by the National Institute of Allergy and Infectious Diseases (R21AI126024 to WPO, R01AI146849 to WPO and SMT).<\/jats:p>\n                  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