{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,8]],"date-time":"2026-10-08T07:05:34Z","timestamp":1791443134128,"version":"4.3.3"},"reference-count":32,"publisher":"Oxford University Press (OUP)","issue":"6","license":[{"start":{"date-parts":[[2026,2,23]],"date-time":"2026-02-23T00:00:00Z","timestamp":1771804800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"funder":[{"name":"Danish Independent Research Foundation","award":["10.46540\/5243-00013B"],"award-info":[{"award-number":["10.46540\/5243-00013B"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,7,8]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>This study was performed to investigate the clinical characteristics and outcome of patients with herpes simplex (HSV) type 1 encephalitis.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Nationwide, prospective, population-based cohort study using the Danish Study Group for Infections of the Brain database to identify all adults hospitalized with microbiologically confirmed HSV-1 encephalitis from 2015 to 2023 in Denmark. Modified Poisson regression was used to estimate the relative risk (RR) with 95% confidence intervals (CI) for 6-month mortality, adjusted for age, sex, immunocompromise, altered mental status, imaging abnormalities, time to acyclovir (&amp;gt;6 hours from admission), and pathogen. Analysis of acyclovir delay &amp;gt;6 hours was repeated post-hoc using time after lumbar puncture as reference.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>A total of 154 patients with confirmed HSV-1 encephalitis were included, yielding a mean annual incidence of 0.36\/100.000. Frequent symptoms at admission included a history of fever (in 101\/128 [79%]) and confusion (in 99\/154 [78%]). The median times from admission to lumbar puncture and acyclovir treatment were 21 (interquartile range, 6\u201370) and 24 (7\u201374) hours, respectively. The adjusted RR for 6-month mortality was 1.15 (95% CI, 0.39\u20133.41) for acyclovir initiation &amp;gt;6 hours after admission and 1.06 (95% CI, 1.004\u20131.13) for each day of delay after admission. The adjusted RR of 6-month mortality was 1.85 (95% CI, 1.01\u20133.45) for delayed acyclovir treatment of &amp;gt;6 hours since lumbar puncture. Anti N-Methyl-D-aspartate receptor encephalitis was diagnosed in 9\/154 (6%) of patients after HSV-1 encephalitis.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Early recognition of HSV-1 encephalitis remains challenging, and the condition is associated with high mortality. Delayed acyclovir treatment, especially following lumbar puncture, was associated with increased risks of fatal outcome.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/cid\/ciag136","type":"journal-article","created":{"date-parts":[[2026,2,22]],"date-time":"2026-02-22T12:31:16Z","timestamp":1771763476000},"page":"e1384-e1392","source":"Crossref","is-referenced-by-count":8,"title":["Herpes Simplex Virus Type 1 Encephalitis: A Prospective Population-Based Cohort Study"],"prefix":"10.1093","volume":"82","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4799-9846","authenticated-orcid":false,"given":"L\u00e6rke Storgaard","family":"Duerlund","sequence":"first","affiliation":[{"name":"Department of Infectious Diseases, Aalborg University Hospital , Aalborg ,","place":["Denmark"]},{"name":"Department of Clinical Medicine, Aalborg University , Aalborg ,","place":["Denmark"]},{"name":"Department of Neurology, Johns Hopkins Encephalitis Center, Johns Hopkins University, School of 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