{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,17]],"date-time":"2026-05-17T20:12:44Z","timestamp":1779048764713,"version":"3.51.4"},"reference-count":25,"publisher":"American Society of Tropical Medicine and Hygiene","issue":"6","license":[{"start":{"date-parts":[[2022,12,14]],"date-time":"2022-12-14T00:00:00Z","timestamp":1670976000000},"content-version":"unspecified","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2022,12,14]]},"abstract":"<jats:title>ABSTRACT.<\/jats:title>\n<jats:p>Mapping asymptomatic malaria infections, which contribute to the transmission reservoir, is important for elimination programs. This analysis compared the spatiotemporal patterns of symptomatic and asymptomatic <jats:italic>Plasmodium falciparum<\/jats:italic> malaria infections in a cohort study of \u223c25,000 people living in a rural hypoendemic area of about 179 km<jats:sup>2<\/jats:sup> in a small area of the Chittagong Hill Districts of Bangladesh. Asymptomatic infections were identified by active surveillance; symptomatic clinical cases presented for care. Infections were identified by a positive rapid diagnostic test and\/or microscopy. Fifty-three subjects with asymptomatic <jats:italic>P. falciparum<\/jats:italic> infection were compared with 572 subjects with symptomatic <jats:italic>P. falciparum<\/jats:italic> between mid-October 2009 and mid-October 2012 with regard to seasonality, household location, and extent of spatial clustering. We found increased spatial clustering of symptomatic compared with asymptomatic infections, and the areas of high intensity were only sometimes overlapping. Symptomatic cases had a distinct seasonality, unlike asymptomatic infections, which were detected year-round. In a comparison of 42 symptomatic <jats:italic>Plasmodium vivax<\/jats:italic> and 777 symptomatic <jats:italic>P. falciparum<\/jats:italic> cases from mid-October 2009 through mid-March 2015, we found substantial spatial overlap in areas with high infection rates, but the areas with the greatest concentration of infection differed. Detection of both symptomatic <jats:italic>P. falciparum<\/jats:italic> and symptomatic <jats:italic>P. vivax<\/jats:italic> infections was greater during the May-to-October high season, although a greater proportion of <jats:italic>P. falciparum<\/jats:italic> cases occurred during the high season compared with <jats:italic>P. vivax<\/jats:italic>. These findings reinforce that passive malaria surveillance and treatment of symptomatic cases will not eliminate the asymptomatic reservoirs that occur distinctly in time and space.<\/jats:p>","DOI":"10.4269\/ajtmh.21-0121","type":"journal-article","created":{"date-parts":[[2022,9,19]],"date-time":"2022-09-19T12:36:41Z","timestamp":1663591001000},"page":"1210-1217","source":"Crossref","is-referenced-by-count":2,"title":["Temporal and Spatial Differences between Symptomatic and Asymptomatic Malaria Infections in the Chittagong Hill Districts, Bangladesh"],"prefix":"10.4269","volume":"107","author":[{"given":"Kerry L.","family":"Shannon","sequence":"first","affiliation":[{"name":"Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland;"},{"name":"Department of Emergency Medicine, Johns Hopkins School of Medicine, Baltimore, Maryland;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Timothy","family":"Shields","sequence":"additional","affiliation":[{"name":"Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland;"},{"name":"Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sabeena","family":"Ahmed","sequence":"additional","affiliation":[{"name":"Infectious Diseases Division, International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hafizur","family":"Rahman","sequence":"additional","affiliation":[{"name":"Laboratory Sciences and Services Division, International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chai Shwai","family":"Prue","sequence":"additional","affiliation":[{"name":"Infectious Diseases Division, International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jacob","family":"Khyang","sequence":"additional","affiliation":[{"name":"Infectious Diseases Division, International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Malathi","family":"Ram","sequence":"additional","affiliation":[{"name":"Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"M. 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