{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,11]],"date-time":"2026-08-11T07:36:10Z","timestamp":1786433770061,"version":"build-2736575974"},"update-to":[{"DOI":"10.1371\/journal.pntd.0013242","type":"new_version","label":"New version","source":"publisher","updated":{"date-parts":[[2026,1,28]],"date-time":"2026-01-28T00:00:00Z","timestamp":1769558400000}}],"reference-count":36,"publisher":"Public Library of Science (PLoS)","issue":"1","license":[{"start":{"date-parts":[[2026,1,21]],"date-time":"2026-01-21T00:00:00Z","timestamp":1768953600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000865","name":"Bill and Melinda Gates Foundation","doi-asserted-by":"publisher","award":["IV-008335"],"award-info":[{"award-number":["IV-008335"]}],"id":[{"id":"10.13039\/100000865","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.plosntds.org"],"crossmark-restriction":false},"short-container-title":["PLoS Negl Trop Dis"],"abstract":"<jats:sec id=\"sec001\">\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>While typhoid conjugate vaccines (TCV) offer promise for reducing risk in endemic settings, their population-level impact remains unclear. In 2022, Nepal introduced TCV nationally on the heels of the COVID-19 pandemic, which disrupted healthcare services, surveillance, and potentially typhoid transmission dynamics, complicating vaccine impact evaluation. We investigated the impact of TCV introduction amid shifting typhoid burden during the pandemic.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec002\">\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      We analyzed blood culture data from four Kathmandu Valley health facilities, comparing culture positivity for\n                      <jats:italic>Salmonella<\/jats:italic>\n                      Typhi across three periods: pre-pandemic (January 2018-March 2020); pandemic, pre-vaccine introduction (April 2020-March 2022); post-vaccine introduction (April 2022-April 2024). We used multivariable logistic regression to assess\n                      <jats:italic>S.<\/jats:italic>\n                      Typhi positivity, adjusting for month and site, stratified by TCV-eligible children and older, TCV-ineligible populations.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec003\">\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Between January 2018 and April 2024, 62,236 blood cultures were performed.\n                      <jats:italic>S.<\/jats:italic>\n                      Typhi blood culture positivity decreased from 2.11% pre-pandemic to 0.59% during the pandemic (p\u2009&lt;\u20090.001) and remained low at 0.69% after TCV introduction. Among TCV-eligible children (15 months to 15 years), odds of\n                      <jats:italic>S.<\/jats:italic>\n                      Typhi positivity during the pandemic were 47% lower than the pre-COVID period (aOR 0.53, 95% CI 0.29-0.90) and continued to decrease by 75% post-TCV introduction (aOR 0.25, 95% CI 0.11-0.55). In contrast, among vaccine-ineligible individuals (\u226516 years), odds of positivity during the pandemic were 77% lower than the pre-COVID period (aOR 0.23, 95% CI 0.16-0.31) but increased by 59% following TCV rollout (aOR 1.59, 95% CI 1.14-2.27). Sensitivity analyses restricted to pathogen-positive cultures yielded similar results.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec004\">\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>\n                      <jats:italic>S.<\/jats:italic>\n                      Typhi blood culture positivity declined sharply during the pandemic before TCV introduction. The subsequent rollout of TCV substantially reduced typhoid burden in vaccine-eligible children; however, rising cases among older, vaccine-ineligible populations following the relaxation of pandemic measures highlights the need for additional control measures such as improved water and sanitation infrastructure and broader age eligibility for typhoid vaccination.\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.1371\/journal.pntd.0013242","type":"journal-article","created":{"date-parts":[[2026,1,21]],"date-time":"2026-01-21T18:42:17Z","timestamp":1769020937000},"page":"e0013242","update-policy":"https:\/\/doi.org\/10.1371\/journal.pntd.corrections_policy","source":"Crossref","is-referenced-by-count":3,"title":["Impact of the COVID-19 pandemic and typhoid conjugate vaccine introduction on typhoid fever in Nepal"],"prefix":"10.1371","volume":"20","author":[{"given":"Dipesh","family":"Tamrakar","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shiva Ram","family":"Naga","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5073-8749","authenticated-orcid":true,"given":"Esther","family":"Jung","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Basudha","family":"Shrestha","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pratibha","family":"Bista Roka","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rabin","family":"Pokharel","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sabin Bikram","family":"Shahi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aarjya Tara","family":"Bajracharya","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Surendra K.","family":"Mahadup","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nishan","family":"Katuwal","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kate","family":"Doyle","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jessica C.","family":"Seidman","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alice S.","family":"Carter","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stephen P.","family":"Luby","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Isaac I.","family":"Bogoch","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kristen","family":"Aiemjoy","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Denise O.","family":"Garrett","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rajeev","family":"Shrestha","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5967-251X","authenticated-orcid":true,"given":"Jason R.","family":"Andrews","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2026,1,21]]},"reference":[{"issue":"2","key":"pntd.0013242.ref001","doi-asserted-by":"crossref","DOI":"10.1371\/journal.pntd.0005376","article-title":"The burden of typhoid fever in low- and middle-income countries: A meta-regression approach","volume":"11","author":"M Antill\u00f3n","year":"2017","journal-title":"PLoS Negl Trop Dis"},{"issue":"10159","key":"pntd.0013242.ref002","doi-asserted-by":"crossref","first-page":"1923","DOI":"10.1016\/S0140-6736(18)32225-6","article-title":"Global, regional, and national comparative risk assessment of 84 behavioural, environmental and occupational, and metabolic risks or clusters of risks for 195 countries and territories, 1990-2017: a systematic analysis for the Global Burden of Disease Study 2017","volume":"392","year":"2018","journal-title":"Lancet"},{"issue":"10","key":"pntd.0013242.ref003","doi-asserted-by":"crossref","DOI":"10.1016\/S2214-109X(14)70301-8","article-title":"Burden of typhoid fever in low-income and middle-income countries: a systematic, literature-based update with risk-factor adjustment","volume":"2","author":"V Mogasale","year":"2014","journal-title":"Lancet Glob Health"},{"issue":"2","key":"pntd.0013242.ref004","doi-asserted-by":"crossref","first-page":"214","DOI":"10.1016\/j.vaccine.2018.04.022","article-title":"Typhoid vaccines: WHO position paper, March 2018 - 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