{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T11:09:19Z","timestamp":1790075359038,"version":"4.0.1"},"reference-count":39,"publisher":"Public Library of Science (PLoS)","issue":"1","license":[{"start":{"date-parts":[[2025,1,31]],"date-time":"2025-01-31T00:00:00Z","timestamp":1738281600000},"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>Background<\/jats:title>\n                    <jats:p>COVID-19 caused a profound global impact, resulting in significant cases and deaths. The progression of COVID-19 clinical manifestations is influenced by a dysregulated inflammatory response. Early identification of the subclinical progression is crucial for timely intervention and improved patient outcomes. While there are various biomarkers to predict disease severity and outcomes, their accessibility and affordability pose challenges in resource-limited settings. We explored the potentiality of the neutrophil-to-lymphocyte ratio (NLR) as a cost-effective inflammatory marker to predict disease severity, clinical deterioration, and mortality in affected patients.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec002\">\n                    <jats:title>Methodology<\/jats:title>\n                    <jats:p>\n                      A hospital-based retrospective cohort study was conducted at KCMC Hospital among COVID-19 patients followed from admission to discharge between 1\n                      <jats:sup>st<\/jats:sup>\n                      March 2020 and 31\n                      <jats:sup>st<\/jats:sup>\n                      March 2022. NLR was calculated as the absolute neutrophil count in \u03bcL divided by the absolute lymphocyte count in \u03bcL. The NLR cut-off value was determined using Receiver Operating Characteristic (ROC) analysis and assessed its predictive ability at admission for in-hospital mortality. The Chi-square test compared the proportion of NLR by patient characteristics. The association of NLR with disease severity and mortality was analyzed using the modified Poisson and Cox regression models, respectively.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec003\">\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>The study included 504 patients, with a median age of 64 years, 57.1% were males, and 68.3% had severe COVID-19. The in-hospital COVID-19 mortality rate was 37.7%. An NLR cutoff value of 6.1 or higher had a sensitivity of 92.1% (95% CI 89.2%\u201394.0%) and a specificity of 92.0% (95% CI 89.7%\u201394.4%). Additionally, 39.5% of patients with an NLR value of 6.1 or higher had increased risk of severe disease, subsequent clinical deterioration, and mortality.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec004\">\n                    <jats:title>Conclusion and recommendation<\/jats:title>\n                    <jats:p>An NLR value of 6.1 or higher at the time of hospital admission associated with severe disease, clinical deterioration, and mortality in patients with COVID-19. Integration of NLR as a prognostic parameter in COVID-19 prognosis scales could improve risk assessment and guide appropriate management strategies for COVID-19 patients, as well as for potential future viral-related pneumonias. Further prospective studies are necessary to validate these findings and evaluate the clinical utility of NLR in larger cohorts of patients.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1371\/journal.pone.0300231","type":"journal-article","created":{"date-parts":[[2025,1,31]],"date-time":"2025-01-31T13:43:11Z","timestamp":1738330991000},"page":"e0300231","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":6,"title":["Neutrophil-to-lymphocyte ratio as a prognostic indicator in COVID-19: Evidence from a northern tanzanian cohort"],"prefix":"10.1371","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6392-8947","authenticated-orcid":true,"given":"Norman Jonas","family":"Kyala","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9861-5879","authenticated-orcid":true,"given":"Innocent","family":"Mboya","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elichilia","family":"Shao","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Francis","family":"Sakita","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kajiru Gadiel","family":"Kilonzo","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Laura","family":"Shirima","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7812-8042","authenticated-orcid":true,"given":"Abid","family":"Sadiq","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elifuraha","family":"Mkwizu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nyasatu","family":"Chamba","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Annette","family":"Marandu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sophia","family":"Muhali","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Faryal","family":"Raza","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eliasa","family":"Ndale","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Damas","family":"Bayo","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-7763-9346","authenticated-orcid":true,"given":"Daniel","family":"Mujuni","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Furaha","family":"Lyamuya","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2025,1,31]]},"reference":[{"issue":"4","key":"pone.0300231.ref001","doi-asserted-by":"crossref","first-page":"271","DOI":"10.1620\/tjem.250.271","article-title":"The Coronavirus Disease 2019 (COVID-19) Pandemic.","volume":"250","author":"S Baloch","journal-title":"Tohoku J Exp Med"},{"issue":"1","key":"pone.0300231.ref002","first-page":"157","article-title":"WHO Declares COVID-19 a Pandemic.","volume":"91","author":"D Cucinotta","year":"2020","journal-title":"Acta Biomed [Internet]."},{"issue":"2","key":"pone.0300231.ref003","doi-asserted-by":"crossref","first-page":"279","DOI":"10.1016\/j.knee.2020.04.003","article-title":"Novel Coronavirus (COVID-19): A Global Pandemic.","volume":"27","author":"O Al-Dadah","year":"2020","journal-title":"Knee."},{"key":"pone.0300231.ref004","article-title":"An overview of 2019 novel coronavirus COVID-19 pandemic: A review study.","author":"VH Garosi","year":"2021","journal-title":"J Educ Health Promot [Internet]."},{"key":"pone.0300231.ref005","unstructured":"WHO. WHO COVID-19 DASHBOARD. 2022 [cited 2022 Jul 7]. WHO Coronavirus (COVID-19) Dashboard | WHO Coronavirus (COVID-19) Dashboard With Vaccination Data. Available from: https:\/\/covid19.who.int\/."},{"key":"pone.0300231.ref006","volume-title":"Clinical management Clinical management\u202f: Living guidance COVID-19.","author":"WHO","year":"2021"},{"issue":"11","key":"pone.0300231.ref007","doi-asserted-by":"crossref","first-page":"1061","DOI":"10.1001\/jama.2020.1585","article-title":"Clinical Characteristics of 138 Hospitalized Patients With 2019 Novel Coronavirus\u2013Infected Pneumonia in Wuhan, China.","volume":"323","author":"D Wang","journal-title":"JAMA"},{"issue":"12","key":"pone.0300231.ref008","doi-asserted-by":"crossref","first-page":"4895","DOI":"10.1111\/1462-2920.15302","article-title":"Immunology of COVID-19","volume":"22","author":"H. 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