{ "schemaVersion": 2, "eyebrow": "Infectious Diseases", "title": "Arboviral Encephalitis", "summary": "Arboviral encephalitis requires early syndromic stabilization, empiric acyclovir while treatable causes are evaluated, and epidemiologically targeted serology coordinated with public health laboratories. Interpretation is complicated by flavivirus antibody cross-reactivity and impaired humoral responses in B-cell-depleted patients.", "seoDescription": "Clinical approach to arboviral encephalitis: stabilization, empiric acyclovir, targeted testing, flavivirus serology interpretation, and public health reporting.", "clinicalQuestion": "How should physicians evaluate, confirm, and manage suspected arboviral encephalitis in the United States?", "specialty": "Infectious Diseases", "audience": "U.S. physicians and medical trainees", "tags": [ "arboviral encephalitis", "West Nile virus", "Eastern equine encephalitis", "La Crosse encephalitis", "arboviral neuroinvasive disease", "flavivirus serology", "PRNT" ], "keyTakeaways": [ "Treat suspected encephalitis as an acute neurologic emergency: initiate empiric acyclovir while diagnostic studies are pending, because herpes simplex encephalitis remains a treatable competing diagnosis. [9]", "Select arboviral testing by illness timing, immune status, vaccination and travel history, local circulation, and the regional differential; similar CNS syndromes are produced by many infectious and noninfectious disorders. [12]", "Positive flavivirus IgM or IgG screening results are not species-specific; confirmatory plaque-reduction neutralization testing is recommended to distinguish cross-reactive flavivirus infections. [12]", "Patients receiving rituximab or related B-cell-depleting therapies are at particularly high risk for severe arboviral neuroinvasive disease and may have atypical diagnostic challenges. [14][20]", "There is no established virus-directed therapy in the supplied evidence; management of arboviral encephalitis is supportive, with ICU-level organ and neurologic support when indicated. [2][5][6]" ], "sections": [ { "id": "when-to-suspect", "eyebrow": "Recognition", "heading": "When to suspect arboviral encephalitis", "intro": "Use epidemiology to prioritize testing, not to exclude competing treatable causes.", "paragraphs": [ "Arboviruses can produce a spectrum from clinically inapparent infection or nonspecific febrile illness to meningitis, encephalitis, and death. Neuroinvasive disease should enter the differential for acute febrile neurologic illness during vector season, after relevant mosquito or tick exposure, in an area with known circulation, or after travel to an endemic region. [12][17]", "In the United States, West Nile virus is the most commonly diagnosed arboviral disease and a leading consideration in seasonal neuroinvasive illness; however, regional alternatives matter. California serogroup viruses, including La Crosse virus, are important causes of pediatric arboviral encephalitis, particularly in Midwest and Appalachian regions. [18][19]", "Do not anchor on arbovirus. The differential for arboviral CNS disease includes other viral, bacterial, mycoplasmal, protozoal, fungal, toxic, metabolic, and postinfectious conditions. Parallel evaluation for alternative, potentially treatable etiologies is necessary. [12]" ], "bullets": [ "Increase suspicion in patients with fever followed by confusion, tremor, focal neurologic deficits, ascending paralysis, progressive cognitive decline, unresponsiveness, or coma, especially when immunocompromised. [14]", "Ask specifically about onset location, travel, outdoor and vector exposure, season, vaccination history, and local public-health alerts; these variables inform test selection and interpretation. [12][17]", "Consider unusual or imported arboviruses in international travelers and report suspected unusual arboviral etiologies promptly to local or state public health authorities. [17]" ], "subsections": [], "table": { "caption": "Epidemiologic features that should redirect arboviral testing strategy. [12][17][18]", "columns": [ "Clinical context", "Testing implication" ], "rows": [ [ "Acute neurologic syndrome during local mosquito or tick season", "Order testing for arboviruses active or present in the relevant geographic region rather than West Nile virus testing alone. [12]" ], [ "Child with encephalitis in Midwest or Appalachian region", "Include California serogroup viruses, particularly La Crosse virus, in the diagnostic differential. [18]" ], [ "International travel or unusual exposure history", "Broaden beyond endemic U.S. agents and notify public health authorities when exotic arboviral infection is suspected. [17]" ], [ "Rituximab or related B-cell depletion", "Maintain heightened concern for severe neuroinvasive disease and coordinate early with infectious diseases, neurology, and public health laboratory services. [14][20]" ] ] } }, { "id": "initial-management", "eyebrow": "First hours", "heading": "Stabilize first and cover treatable encephalitis", "intro": "Arboviral confirmation should not delay emergency encephalitis care.", "paragraphs": [ "Patients can deteriorate rapidly from impaired consciousness, seizures, autonomic dysfunction, cerebral edema, or respiratory failure. ICU admission is appropriate when airway protection, ventilatory support, circulatory support, or close neurologic monitoring is required. [2][5][7]", "Start acyclovir in all patients with suspected encephalitis while diagnostic studies are pending. This recommendation is directed at empiric coverage of herpes simplex virus and should not be interpreted as evidence of activity against arboviruses. [9]", "Once arboviral encephalitis is the working diagnosis, treatment is supportive. The supplied evidence does not establish a specific antiviral, immunotherapy, or corticosteroid regimen that improves arboviral encephalitis outcomes. [2][6][18]" ], "bullets": [ "Protect the airway when altered consciousness compromises airway reflexes; provide ventilatory and hemodynamic support as clinically indicated. [2][5][7]", "Monitor for and treat seizures; manage suspected intracranial hypertension or cerebral edema using critical-care and neurocritical-care principles, recognizing that efficacy of reported adjunctive therapies in encephalitis is unproven in the supplied evidence. [7]", "Continue surveillance for secondary complications including pneumonia, venous thromboembolism, dysnatremias, arrhythmias, and hypotension in severe disease. [7]", "Avoid premature discontinuation of empiric therapy for other treatable CNS infections until the diagnostic evaluation and clinical course justify de-escalation. [9][12]" ], "subsections": [], "table": { "caption": "Immediate management priorities in suspected arboviral encephalitis. [2][5][7][9]", "columns": [ "Priority", "Action", "Clinical rationale" ], "rows": [ [ "Airway and ventilation", "Escalate to ICU-level monitoring and intubate when airway protection is compromised. [2][5][7]", "Encephalitis may cause rapid neurologic decline and respiratory failure. [2][5]" ], [ "Treatable viral encephalitis coverage", "Initiate empiric acyclovir pending diagnostic results. [9]", "HSV encephalitis is a time-sensitive alternative diagnosis; this does not treat arboviral infection. [9]" ], [ "Neurologic complications", "Monitor for seizures, cerebral edema, autonomic instability, and dysnatremias; intervene according to critical-care assessment. [7]", "These complications contribute materially to morbidity in severe encephalitis. [7]" ], [ "Supportive care", "Provide organ support and prevent complications of critical illness. [2][5][7]", "Supportive care is the mainstay for arboviral encephalitis. [2][6]" ] ] } }, { "id": "diagnostic-testing", "eyebrow": "Diagnosis", "heading": "Order epidemiologically targeted testing and interpret serology cautiously", "intro": "Laboratory confirmation depends on agent-specific assays and context.", "paragraphs": [ "Definitive arboviral diagnosis requires laboratory testing with specific reagents. Test selection should account for age, immune status, vaccination history, timing of infection, pathogens in the differential, and the capabilities of initial and confirmatory laboratories. [12]", "Send serum and CSF as appropriate for arboviral testing and involve the hospital laboratory, state health department, or public health laboratory early when a neuroinvasive arboviral syndrome is suspected. Specimens submitted for West Nile virus testing should also be assessed for other arboviruses known to be active or present in the relevant area or travel region. [12]", "Flavivirus serology has a major interpretive limitation: IgM and IgG assays may cross-react among West Nile, St. Louis encephalitis, dengue, yellow fever, Powassan, and other flaviviruses. Treat initial flavivirus antibody results as screening results and pursue plaque-reduction neutralization testing for species differentiation when confirmation is clinically or epidemiologically important. [12]", "B-cell depletion changes both risk and diagnostic reasoning. CDC describes severe neuroinvasive arboviral disease among patients receiving rituximab and related agents, with a reported case-series mortality of 4 of 5 patients diagnosed with arboviral neuroinvasive disease; survivors often had long-term cognitive or motor disability. A negative or delayed antibody response may be a concern in this population, warranting early specialist and public-health laboratory coordination. [14][20]" ], "bullets": [ "Order testing based on the patient's exposure geography and season, not solely on the most common local agent. [12][17]", "Interpret a positive flavivirus screening antibody test alongside prior flavivirus infection, vaccination, travel, and regional circulation; request confirmatory neutralization testing when cross-reactivity is plausible. [12]", "Document immune-modifying therapy, especially anti-CD20 therapy, on laboratory requisitions and in consultations because it materially alters pretest probability and may complicate serologic interpretation. [14]" ], "subsections": [ { "heading": "Neuroimaging", "paragraphs": [ "MRI is generally more informative than CT in encephalitis evaluations. In one large encephalitis study, MRI abnormalities were particularly frequent with herpes simplex virus and acute disseminated encephalomyelitis, underscoring that imaging contributes to the broader differential rather than establishing arboviral etiology. [1]" ], "bullets": [ "Reported Eastern equine encephalitis MRI abnormalities often involve basal ganglia, thalami, and brainstem, but this pattern is not sufficient for diagnosis without compatible epidemiology and laboratory confirmation. [24]" ] } ], "table": { "caption": "Practical interpretation of arboviral laboratory testing. [12][14]", "columns": [ "Result or circumstance", "Interpretation", "Next action" ], "rows": [ [ "Positive flavivirus IgM or IgG screening assay", "Possible recent or prior flavivirus exposure, but cross-reactivity limits species attribution. [12]", "Request confirmatory plaque-reduction neutralization testing when clinically or epidemiologically necessary. [12]" ], [ "West Nile virus testing requested in a patient with compatible syndrome", "West Nile virus is common, but other regional arboviruses may produce indistinguishable presentations. [12][19]", "Ensure testing includes other arboviruses active or present in the exposure region. [12]" ], [ "Negative or nondiagnostic serology in B-cell-depleted patient", "Humoral testing may be difficult to interpret in a host at high risk for severe disease. [14]", "Consult infectious diseases and public health laboratory services early for case-specific diagnostic planning. [14]" ], [ "Suspected imported or unusual arbovirus", "Potential public-health risk, particularly where competent vectors exist. [17]", "Report promptly to local or state public health agencies and coordinate specialized testing. [17]" ] ] } }, { "id": "public-health-prevention", "eyebrow": "Public Health", "heading": "Report promptly and use diagnosis to guide prevention", "intro": "Clinical confirmation has individual and population-level value.", "paragraphs": [ "Timely diagnosis and reporting can clarify exposure source, prevent unnecessary antimicrobial treatment, and allow public health authorities to detect and respond to additional cases. [14]", "Counsel patients, particularly those who are immunocompromised, on seasonal and geographic risk and on personal measures to prevent mosquito and tick bites. [14] There is no routine human vaccine strategy for the major endemic U.S. arboviral encephalitides described in the supplied sources; prevention therefore relies primarily on vector-exposure reduction and public-health surveillance." ], "bullets": [ "Notify local or state public health authorities for suspected arboviral disease, particularly neuroinvasive, unusual, travel-associated, or clustered cases. [14][17]", "For positive flavivirus screening results, coordinate confirmatory testing through appropriate public health channels because species-level attribution may affect surveillance and response. [12]", "Provide targeted prevention counseling to patients receiving B-cell-depleting therapy because severe neuroinvasive outcomes have been reported in this group. [14][20]" ], "subsections": [], "table": { "caption": "Reporting and prevention actions with clinical value. [12][14][17]", "columns": [ "Situation", "Physician action" ], "rows": [ [ "Suspected arboviral neuroinvasive disease", "Report to local or state public health authorities and coordinate agent-specific testing. [14][17]" ], [ "Flavivirus screening-seropositive specimen", "Arrange confirmatory plaque-reduction neutralization testing when differentiation is needed. [12]" ], [ "Immunocompromised patient at seasonal risk", "Discuss mosquito and tick bite prevention and maintain a lower threshold for evaluation of febrile neurologic illness. [14]" ] ] } } ], "faq": [ { "question": "Should empiric acyclovir be given when arboviral encephalitis is suspected?", "answer": "Yes. Acyclovir should be started in all patients with suspected encephalitis while diagnostic studies are pending because a treatable herpes simplex virus encephalitis remains in the differential. It is not established therapy for arboviral infection. [9]" }, { "question": "How should a positive West Nile or other flavivirus IgM test be interpreted?", "answer": "Interpret it as a screening result rather than definitive species identification. Flavivirus IgM and IgG tests can cross-react, so plaque-reduction neutralization testing is recommended when differentiation among flaviviruses is required. [12]" }, { "question": "When should physicians test beyond West Nile virus?", "answer": "Test for other arboviruses active or present in the patient's exposure region or travel destination, because multiple arboviruses produce overlapping meningitis and encephalitis syndromes. [12][17]" }, { "question": "Why is rituximab exposure important in suspected arboviral encephalitis?", "answer": "B-cell depletion is associated with severe arboviral neuroinvasive disease. CDC reports high mortality and long-term neurologic disability in a rituximab-associated case series, supporting heightened suspicion and early specialist and public-health laboratory involvement. 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Verify recommendations against current guidance and patient-specific factors.", "citations": [ { "number": 1, "title": "Causes of encephalitis and differences in their clinical ...", "detail": "www.thelancet.com", "url": "https://www.thelancet.com/article/S1473-3099(10)70222-X/fulltext", "authors": "www.thelancet.com", "host": "www.thelancet.com", "snippet": "by J Granerod · 2010 · Cited by 1791 — CT and abnormal MRI findings, MRI was most likely to be abnormal in patients with ADEM and herpes simplex virus and least likely to be abnormal", "score": 0.21031219 }, { "number": 2, "title": "Eastern Equine Encephalitis Virus — Another Emergent ...", "detail": "www.nejm.org", "url": "https://www.nejm.org/doi/full/10.1056/NEJMp1914328", "authors": "www.nejm.org", "host": "www.nejm.org", "snippet": "by DM Morens · 2019 · Cited by 106 — Supportive care, often including admission to an intensive care unit with ventilatory support, is the mainstay of treatment. Patients need", "score": 0.3433643 }, { "number": 3, "title": "Flavivirus Encephalitis", "detail": "www.nejm.org", "url": "https://www.nejm.org/doi/full/10.1056/NEJMra030476", "authors": "www.nejm.org", "host": "www.nejm.org", "snippet": "by T Solomon · 2004 · Cited by 528 — A crude formalin-inactivated vaccine against West Nile virus is being used to protect horses (in which encephalitis can also develop).", "score": 0.21895353 }, { "number": 4, "title": "Viral Encephalitis", "detail": "www.nejm.org", "url": "https://www.nejm.org/doi/pdf/10.1056/NEJM199007263230406", "authors": "www.nejm.org", "host": "www.nejm.org", "snippet": "by RJ Whitley · 1990 · Cited by 571 — In general, viral encephalitis can be divided into four distinctive categories on the basis of cause and pathogenesis: acute viral encephalitis,", "score": 0.20131063 }, { "number": 5, "title": "Intensive care management of patients with viral encephalitis", "detail": "www.sciencedirect.com", "url": "https://www.sciencedirect.com/science/article/am/pii/S0035378721007864", "authors": "www.sciencedirect.com", "host": "www.sciencedirect.com", "snippet": "by R Sonneville · 2022 · Cited by 29 — Encephalitis often requires ICU admission to ensure oxygenation, airway protection, circulatory support, and prevention and treatment of secondary complications", "score": 0.6972179 }, { "number": 6, "title": "La Crosse Encephalitis - an overview", "detail": "www.sciencedirect.com", "url": "https://www.sciencedirect.com/topics/neuroscience/la-crosse-encephalitis", "authors": "www.sciencedirect.com", "host": "www.sciencedirect.com", "snippet": "Management of arboviral encephalitides is primarily supportive. Because of the risk of progressive worsening of neurologic status in 5% to 15% of La Crosse", "score": 0.60077465 }, { "number": 7, "title": "Allergic Encephalitis - an overview", "detail": "www.sciencedirect.com", "url": "https://www.sciencedirect.com/topics/pharmacology-toxicology-and-pharmaceutical-science/allergic-encephalitis", "authors": "www.sciencedirect.com", "host": "www.sciencedirect.com", "snippet": "#### Management\n\nThe clinical status of patients with encephalitis can deteriorate rapidly; patients should be closely monitored in an intensive care unit or equivalent setting. Viral encephalitis caused by arboviruses or herpesviruses does not require patient isolation for infection control. Respir", "score": 0.5417246 }, { "number": 8, "title": "Predominance of arboviruses in acute encephalitis and ...", "detail": "www.sciencedirect.com", "url": "https://www.sciencedirect.com/science/article/pii/S1201971226002997", "authors": "www.sciencedirect.com", "host": "www.sciencedirect.com", "snippet": "by MS do Rosário · 2026 — Therapeutic strategies reflected clinical presentation. Acyclovir was predominantly administered to encephalitis patients consistent with empiric treatment.", "score": 0.3656158 }, { "number": 9, "title": "Management of Encephalitis: Clinical Practice Guidelines by ...", "detail": "academic.oup.com", "url": "https://academic.oup.com/cid/article/47/3/303/313455", "authors": "academic.oup.com", "host": "academic.oup.com", "snippet": "by XY Lei · 2006 · Cited by 15 — Acyclovir treatment should be initiated in all patients with suspected encephalitis, pending results of diagnostic studies.", "score": 0.1788271 }, { "number": 10, "title": "Epidemic/Epizootic West Nile Virus in the United States", "detail": "stacks.cdc.gov", "url": "https://stacks.cdc.gov/view/cdc/7271/cdc_7271_DS1.pdf", "authors": "stacks.cdc.gov", "host": "stacks.cdc.gov", "snippet": "... Guidelines ... encephalitis); and 7) brief clinical summary including clinical diagnosis (e.g., ... For national arboviral encephalitis surveillance, CDC", "score": 0.61363083 }, { "number": 11, "title": "SURVEILLANCE GUIDE FOR REPORTING ARBOVIRAL ...", "detail": "ndc.services.cdc.gov", "url": "https://ndc.services.cdc.gov/wp-content/uploads/ArboviralDiseaseReportingSurveillanceGuide_December-2021_12-10-21.pdf", "authors": "ndc.services.cdc.gov", "host": "ndc.services.cdc.gov", "snippet": "impaired level of consciousness and/or diagnosis of encephalitis, encephalopathy, or meningitis, or heart or other organ involvement, including myocarditis, cholecystitis, and pancreatitis. • Unknown: Insufficient information to assign a clinical syndrome to a case. You can change this at a later da", "score": 0.61168414 }, { "number": 12, "title": "Guidelines for West Nile Virus Surveillance and Control | West Nile Virus | CDC", "detail": "www.cdc.gov", "url": "https://www.cdc.gov/west-nile-virus/php/surveillance-and-control-guidelines/index.html", "authors": "www.cdc.gov", "host": "www.cdc.gov", "snippet": "In most patients, infection with an arbovirus that can cause encephalitis is clinically inapparent or causes a nonspecific viral syndrome. Numerous pathogens cause encephalitis, aseptic meningitis, and febrile disease with similar clinical symptoms and presentations and should be considered in the d", "score": 0.609455 }, { "number": 13, "title": "WHO guidelines for clinical management of arboviral diseases:", "detail": "iris.who.int", "url": "https://iris.who.int/server/api/core/bitstreams/634a55a5-327e-459b-a633-0650fe8ad6c9/content", "authors": "iris.who.int", "host": "iris.who.int", "snippet": "University of the Philippines, Manila, Philippines); Liya Wassie (Armauer Hansen Research Institute AHRI, Addis Ababa, Ethiopia). Methodologist: Gordon Guyatt (McMaster University, Canada). Clinical Chair: Marta Lado Castro-Rial (Partners in Health). Co-chair: Erin Staples (Centers for Disease Contr", "score": 0.5914643 }, { "number": 14, "title": "Clinical Guidance for Vector-Borne Viral Diseases in People Who Are Immunocompromised | Vector-Borne Diseases | CDC", "detail": "www.cdc.gov", "url": "https://www.cdc.gov/vector-borne-diseases/hcp/clinical-guidance-immunocompromised/index.html", "authors": "www.cdc.gov", "host": "www.cdc.gov", "snippet": "## Reporting arboviral infections\n\nTimely diagnosis of an arboviral infection in a patient can help with clinical management (e.g., knowing the source of the infection) and treatment decisions (e.g., stopping unnecessary antibiotics). In addition, diagnosis and reporting of arboviral diseases to loc", "score": 0.5883458 }, { "number": 15, "title": "Guidelines for Eastern Equine Encephalitis Virus ...", "detail": "www.cdc.gov", "url": "https://www.cdc.gov/eastern-equine-encephalitis/php/surveillance-and-control-guidelines/index.html", "authors": "www.cdc.gov", "host": "www.cdc.gov", "snippet": "Comprehensive CDC guidelines for arbovirus surveillance programs in the United States were published in 1993 (CDC 1993). These guidelines", "score": 0.53181785 }, { "number": 16, "title": "Arboviral Infections of the Central Nervous System", "detail": "www.cdc.gov", "url": "https://www.cdc.gov/mmwr/PDF/wk/mm4725.pdf", "authors": "www.cdc.gov", "host": "www.cdc.gov", "snippet": "2. Grimstad PR. California serogroup virus disease. In: Monath TP , ed. The arboviruses: epidemiol-ogy and ecology. Vol 2. Boca Raton, Florida: CRC Press, 1988:99–136.\n3. Monath TP . Epidemiology. In: Monath TP , ed. St. Louis encephalitis. Washington, DC: American Public Health Association, 1980:23", "score": 0.50285697 }, { "number": 17, "title": "Arboviral Diseases, Neuroinvasive and Non-neuroinvasive 2014 Case Definition | CDC", "detail": "ndc.services.cdc.gov", "url": "https://ndc.services.cdc.gov/case-definitions/arboviral-diseases-neuroinvasive-and-non-neuroinvasive-2014", "authors": "ndc.services.cdc.gov", "host": "ndc.services.cdc.gov", "snippet": "More than 130 arboviruses are known to cause human disease. Most arboviruses of public health importance belong to one of three virus genera: Flavivirus, Alphavirus, and Bunyavirus.\n\nCalifornia serogroup viruses include:\n\n California encephalitis\n Jamestown Canyon\n Keystone\n La Crosse\n Snowshoe hare", "score": 0.42462727 }, { "number": 18, "title": "Neutralizing Antibodies against California Serogroup Orthobunyaviruses in Human Serum Samples, Montana, USA - Volume 31, Number 4—April 2025 - Emerging Infectious Diseases journal - CDC", "detail": "wwwnc.cdc.gov", "url": "https://wwwnc.cdc.gov/eid/article/31/4/24-1520_article", "authors": "wwwnc.cdc.gov", "host": "wwwnc.cdc.gov", "snippet": "Several arboviruses can invade the central nervous system (CNS) and cause neurologic disease. Diagnosis of the specific arbovirus causing encephalitis often includes measuring neutralizing antibody (NAb) titers to that virus in the blood of patients during and after acute encephalitis. That process ", "score": 0.3995779 }, { "number": 19, "title": "Use of Testing for West Nile Virus and Other Arboviruses - Volume 22, Number 9—September 2016 - Emerging Infectious Diseases journal - CDC", "detail": "wwwnc.cdc.gov", "url": "https://wwwnc.cdc.gov/eid/article/22/9/15-2050_article", "authors": "wwwnc.cdc.gov", "host": "wwwnc.cdc.gov", "snippet": "for only 1% of patients. This finding reflects that, for most patients, inappropriate WNV testing was performed in clinical practice. Finally, arboviral panel diagnostics can help rule out infection with St. Louis encephalitis virus, a less common cause of neuroinvasive disease in this population. [", "score": 0.35985944 }, { "number": 20, "title": "Severe Arboviral Neuroinvasive Disease in Patients on Rituximab Therapy: A Review", "detail": "stacks.cdc.gov", "url": "https://stacks.cdc.gov/view/cdc/125735", "authors": "stacks.cdc.gov", "host": "stacks.cdc.gov", "snippet": "#### Exit Notification/Disclaimer Policy\n\nCDC STACKS serves as an archival repository of CDC-published products including\nscientific findings,\njournal articles, guidelines, recommendations, or other public health information authored or\nco-authored by CDC or funded partners.\n \n \nAs a repository, C", "score": 0.3546794 }, { "number": 21, "title": "evaluation for arboviral infection among children ...", "detail": "stacks.cdc.gov", "url": "https://stacks.cdc.gov/view/cdc/121852/cdc_121852_DS1.pdf", "authors": "stacks.cdc.gov", "host": "stacks.cdc.gov", "snippet": "Arboviral infection should be considered in children with neuroinvasive disease during arboviral season with testing directed toward viruses endemic to the", "score": 0.26822636 }, { "number": 22, "title": "Severe Arboviral Neuroinvasive Disease in Patients on ...", "detail": "stacks.cdc.gov", "url": "https://stacks.cdc.gov/view/cdc/125735/cdc_125735_DS1.pdf", "authors": "stacks.cdc.gov", "host": "stacks.cdc.gov", "snippet": "by RK Kapadia · 2023 · Cited by 37 — West Nile virus is the most common cause of human arboviral disease in North America, with nearly 22 000 disease cases reported in the United States from 2009", "score": 0.21765368 }, { "number": 23, "title": "Arbovirus Epidemics as Global Health Imperative, Africa, 2023 - Volume 31, Number 2—February 2025 - Emerging Infectious Diseases journal - CDC", "detail": "wwwnc.cdc.gov", "url": "https://wwwnc.cdc.gov/eid/article/31/2/24-0754_article", "authors": "wwwnc.cdc.gov", "host": "wwwnc.cdc.gov", "snippet": "fever outbreak and its etiology and inform real-time public health actions, resulting in accurate and timely disease management and control (30). The ability of genomic sequencing to rapidly identify and characterize reemerging viruses offers a valuable opportunity for enhancing public health survei", "score": 0.18038115 }, { "number": 24, "title": "Successful Treatment of Eastern Equine Encephalitis with ...", "detail": "www.neurology.org", "url": "https://www.neurology.org/doi/10.1212/WNL.84.14_supplement.P6.306", "authors": "www.neurology.org", "host": "www.neurology.org", "snippet": "Cerebrospinal fluid (CSF) profile is similar to other viral encephalitides, and MRI usually shows abnormalities within the basal ganglia, thalami, and brainstem", "score": 0.23309521 } ], "publishedAt": "2026-08-21T01:22:06.156634+00:00", "updatedAt": "2026-08-21T01:22:06.156634+00:00", "readingMinutes": 5, "slug": "arboviral-encephalitis" }