{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"institution":[{"name":"medRxiv"}],"indexed":{"date-parts":[[2026,7,17]],"date-time":"2026-07-17T18:17:50Z","timestamp":1784312270786,"version":"3.55.0"},"posted":{"date-parts":[[2026,6,9]]},"group-title":"Epidemiology","reference-count":41,"publisher":"openRxiv","license":[{"start":{"date-parts":[[2026,6,9]],"date-time":"2026-06-09T00:00:00Z","timestamp":1780963200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"funder":[{"name":"National Institute of Allergy and Infectious Diseases of the National Institutes of Health","award":["1R01AI147321-01"],"award-info":[{"award-number":["1R01AI147321-01"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"accepted":{"date-parts":[[2026,6,9]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                <jats:sec>\n                  <jats:title>Background<\/jats:title>\n                  <jats:p>\n                    Tuberculosis remains the leading infectious cause of death worldwide. In the WHO African region, declining incidence has coincided with antiretroviral therapy (ART) scale-up, though whether this reflects reduced progression to disease or reduced transmission is unclear. We evaluated how ART and symptom status influence within-household\n                    <jats:italic>Mycobacterium tuberculosis complex<\/jats:italic>\n                    (MTBC) transmission risk.\n                  <\/jats:p>\n                <\/jats:sec>\n                <jats:sec>\n                  <jats:title>Methods<\/jats:title>\n                  <jats:p>We conducted a case-contact household study in rural South Africa, enrolling index adults with bacteriologically-confirmed pulmonary tuberculosis. MTBC immunoreactivity was measured in all child household contacts (aged 2-14 years) as a proxy measure of within-household transmission. We assessed the influence of index person ART status and symptom status and explored effect-measure modification of the association between index person HIV status and transmission risk by sex.<\/jats:p>\n                <\/jats:sec>\n                <jats:sec>\n                  <jats:title>Results<\/jats:title>\n                  <jats:p>Among 755 child contacts of 296 index persons, effective ART was not associated with within-household MTBC transmission risk (risk ratio [RR], 1.07; 95% CI, 0.66\u20131.74). Among PLHIV engaged in ART care, WHO TB four-symptom screen (WHO4SS) status was not associated with transmission risk (RR, 0.80; 95% CI, 0.43\u20131.47), although absence of reported cough reduced risk (RR, 0.61; 95% CI, 0.38\u20130.96). A pronounced interaction between sex and HIV status was observed: HIV-negative women had the highest within-household MTBC transmission risk (30.5% vs. 14.3% in women with HIV) whereas risks were similar between HIV-positive and HIV-negative men.<\/jats:p>\n                <\/jats:sec>\n                <jats:sec>\n                  <jats:title>Conclusions<\/jats:title>\n                  <jats:p>We found no evidence that effective ART or WHO4SS status influenced within-household MTBC transmission risk, though confidence intervals were wide. Absence of reported cough was associated with lower risk, and transmission risk was highest among child contacts of HIV-negative women. These findings suggest reported cough is a useful marker of transmission risk and that routine tuberculosis screening within ART care may reduce transmission from PLHIV; intensified efforts are nonetheless needed to achieve earlier tuberculosis detection in HIV-negative individuals.<\/jats:p>\n                <\/jats:sec>","DOI":"10.64898\/2026.06.01.26354571","type":"posted-content","created":{"date-parts":[[2026,6,9]],"date-time":"2026-06-09T23:30:13Z","timestamp":1781047813000},"source":"Crossref","is-referenced-by-count":1,"title":["Within-household transmission risk of pulmonary tuberculosis in the era of universal antiretroviral therapy"],"prefix":"10.64898","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0873-8355","authenticated-orcid":false,"given":"Palwasha Y","family":"Khan","sequence":"first","affiliation":[{"name":"TB centre, London School of Hygiene & Tropical Medicine, London, United Kingdom"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Indira","family":"Govender","sequence":"additional","affiliation":[{"name":"TB centre, London School of Hygiene & Tropical Medicine, London, United Kingdom"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nicky","family":"McCreesh","sequence":"additional","affiliation":[{"name":"TB centre, London School of Hygiene & Tropical Medicine, London, United Kingdom"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mareca","family":"Sithole","sequence":"additional","affiliation":[{"name":"Africa Health Research Institute, KwaZulu-Natal, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Edwin","family":"Mkwanazi","sequence":"additional","affiliation":[{"name":"Africa Health Research Institute, KwaZulu-Natal, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4233-9080","authenticated-orcid":false,"given":"Sedona","family":"Sweeney","sequence":"additional","affiliation":[{"name":"TB centre, London School of Hygiene & Tropical Medicine, London, United Kingdom"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gregory","family":"Ording-Jespersen","sequence":"additional","affiliation":[{"name":"Africa Health Research Institute, KwaZulu-Natal, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4755-5380","authenticated-orcid":false,"given":"Emily","family":"Wong","sequence":"additional","affiliation":[{"name":"Africa Health Research Institute, KwaZulu-Natal, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Willem","family":"Hanekom","sequence":"additional","affiliation":[{"name":"Africa Health Research Institute, KwaZulu-Natal, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4132-7467","authenticated-orcid":false,"given":"Rein MGJ","family":"Houben","sequence":"additional","affiliation":[{"name":"TB centre, London School of Hygiene & Tropical Medicine, London, United Kingdom"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Richard G","family":"White","sequence":"additional","affiliation":[{"name":"TB centre, London School of Hygiene & Tropical Medicine, London, United Kingdom"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Theresa K","family":"Smit","sequence":"additional","affiliation":[{"name":"Africa Health Research Institute, KwaZulu-Natal, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Matthew J","family":"Smith","sequence":"additional","affiliation":[{"name":"Department of Medical Statistics, London School of Hygiene & Tropical Medicine, London, United Kingdom"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6524-3754","authenticated-orcid":false,"given":"Katherine","family":"Fielding","sequence":"additional","affiliation":[{"name":"TB centre, London School of Hygiene & Tropical Medicine, London, United Kingdom"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2437-5195","authenticated-orcid":false,"given":"Alison D","family":"Grant","sequence":"additional","affiliation":[{"name":"TB centre, London School of Hygiene & Tropical Medicine, London, United Kingdom"},{"name":"Africa Health Research Institute, KwaZulu-Natal, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"54368","reference":[{"key":"2026061200450619000_2026.06.01.26354571v1.1","unstructured":"WHO. 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