West Nile Virus Natural History

This study has been completed.
Information provided by:
National Institute of Allergy and Infectious Diseases (NIAID)
ClinicalTrials.gov Identifier:
First received: August 26, 2005
Last updated: November 3, 2011
Last verified: February 2010

West Nile Virus causes an infection that is spread to humans when bitten by certain types of mosquitoes. Mosquitoes become infected by biting infected birds. The purpose of this study is to find out more about West Nile Virus, which may assist in the design of better treatments. The study will be looking at the effects of the disease on individuals, specifically their nervous systems, and the outcomes of the disease. Study participants will include 120 adults ages 18 and older, who have either a fever and/or changes in their neurological (involving the brain and nervous system) status due to documented West Nile Virus infection. Study procedures will include physical examinations, blood tests, urine tests, cerebral spinal fluid (fluid in and around the brain and spinal cord) tests, and neurological (nervous system) testing. Study participants will be followed for 12 months.

West Nile Virus

Study Type: Observational
Study Design: Observational Model: Cohort
Time Perspective: Prospective
Official Title: Investigation of the Natural History of West Nile Virus Infection in Patients With Recently Acquired West Nile Fever or Neuroinvasive Disease

Resource links provided by NLM:

Further study details as provided by National Institute of Allergy and Infectious Diseases (NIAID):

Primary Outcome Measures:
  • Identify and describe the mortality and morbidity, specifically neurologic and functional outcomes of patients with West Nile Virus disease. [ Time Frame: Duration of Study. ] [ Designated as safety issue: No ]
  • Characterize the clinical course and diverse manifestations of West Nile Virus disease. [ Time Frame: Duration of Study. ] [ Designated as safety issue: No ]
  • Assess the kinetics of humoral immune responses to West Nile Virus infection, and correlate these responses with clinical outcomes. [ Time Frame: Analysis. ] [ Designated as safety issue: No ]

Biospecimen Retention:   Samples With DNA

Cerebrospinal fluid, urine, serum.

Enrollment: 30
Study Start Date: September 2003
Study Completion Date: December 2008
Primary Completion Date: December 2008 (Final data collection date for primary outcome measure)
West Nile Virus (WNV) Neuroinvasive Disease Cohort
Fever (temperature > 38 C) documented by a health care provider AND: at least one of the following, as documented by a health care provider and in the absence of a more likely clinical explanation: acutely altered mental status; other acute signs of central or peripheral neurologic dysfunction; or cerebrospinal fluid (CSF) pleocytosis associated with illness clinically compatible with meningitis.
West Nile Virus Fever Cohort
Temperature > 38 C as documented by a health care provider.

Detailed Description:

This is a multi-center, prospective, natural history study designed to characterize West Nile Virus (WNV) disease, including functional and neurologic outcomes, in study participants with laboratory documented WNV infection that have symptoms consistent with WNV neuroinvasive disease or WNV fever. The objectives of the study are to: identify and describe the mortality and morbidity, specifically neurologic and functional outcomes of patients with WNV; characterize the clinical course and diverse manifestations of WNV disease; and assess the kinetics of humoral immune responses to WNV infection, and to correlate these responses with clinical outcomes. The study will enroll a proposed sample size 120 study participants ages 18 and older. All study participants will undergo a series of laboratory, neurologic, and physical examinations and will be followed prospectively for one year to characterize the spectrum and sequelae of WNV disease. When patients meet inclusion criteria, informed consent will be obtained, and blood will be collected to perform polymerase chain reaction (PCR), immunoglobulin (Ig)M, and IgG testing for WNV infection. Urine PCR for WNV will also be obtained. Upon enrollment (Day 1), a medical and surgical history, review of systems, travel, vector and blood product history will be obtained, and the baseline neurologic and clinical status will be evaluated. A clinical assessment, including a physical examination, vital signs and laboratory assessment will be performed. Based on history a pre-illness neurologic functional score will be estimated, using the Barthel Index (BI) and the Modified Rankin Scale (MRS). Investigators will assess a Day 1 functional score, using the BI, the Modified Mini-Mental Status Examination (3MS), the Glasgow Outcome Score (GOS), and the Glasgow Coma Scale (GCS) if hospitalized and recorded answers to questions abstracted from the MRS on the day of entry into the study. At study visit Day 1 ± 3, cerebrospinal fluid (CSF) will be obtained and tested for cell count, differential, protein and glucose, IgM, IgG and PCR for WNV infection. If a study participant has a lumbar puncture conducted for standard of care at any time up to 72 hours prior and up to 72 hours after study enrollment, a repeat lumbar puncture will not be necessary if an adequate aliquot of CSF is available for shipment to the Collaborative Antiviral Study Group (CASG) Virology Laboratory and if the required cell count, differential, protein and glucose tests were performed. A brain Magnetic Resonance Imaging (MRI) scan will be done on study visit Day 1 ± 3. If the brain MRI scan on study visit Day 1 ± 3 suggests abnormalities, a repeat MRI scan will be conducted at study visit Day 30 ± 5. If changes (either improvement or worsening) in the WNV related lesions have occurred since the MRI conducted on study visit Day 1 ± 3, a third MRI will be conducted on study visit Day 90 ± 14. Subsequent MRIs will be conducted at study visits 180 ± 21 and 365 ± 30 only if the WNV related lesions continue to improve or worsen: any two MRIs where the WNV related lesions remain stable will obviate the need for further MRI scans. There will be study visits at Day 1, Day 14 ± 3, Day 30 ± 5, Day 90 ± 14, Day 180 ± 21, and Day 365 ± 30. At these visits a brief physical examination will be done, a functional score will be assigned, and blood will be obtained for serologic WNV studies. Neurological endpoints will include the GCS and 4 validated functional and cognitive scoring scales: The BI, MRS, GOS, and 3MS. MRI of spinal cord, electromyogram and nerve conduction studies will be included when available.


Ages Eligible for Study:   18 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population

Adults, 18 and older, all study participants must have been diagnosed with West Nile Virus (WNV) disease within the four months prior to enrollment.


Inclusion Criteria:

Patients, regardless of race or gender, who consent and meet entry criteria, will be enrolled.

  • Greater than or equal to 18 years of age
  • Documented West Nile Virus (WNV) infection (fever or neuroinvasive disease) that began within four months prior to study entry. Illness onset is defined as the first visit to a medical care provider where compatible symptoms (see cohort A and B below) are documented.
  • Local laboratory documentation of WNV infection as defined by positive immunoglobulin (Ig) M and/or polymerase chain reaction (PCR) for WNV in serum or cerebrospinal fluid (CSF) concurrent with or following illness onset.
  • Qualification for A or B Cohort.

Cohort A: Neuroinvasive Disease Cohort:

  • Fever (temperature greater than 38 degrees Celsius) documented by a health care provider.
  • AND: at least one of the following, as documented by a health care provider and in the absence of a more likely clinical explanation:

    1. Acutely altered mental status (e.g., disorientation, obtundation, stupor, or coma),
    2. Other acute signs of central or peripheral neurologic dysfunction (e.g., paresis or paralysis, nerve palsies, sensory deficits, abnormal reflexes, generalized convulsions, or abnormal movements), or
    3. CSF pleocytosis (white blood cell count greater than or equal to 4 per mm^3 corrected for red blood cell contamination in CSF) associated with illness clinically compatible with meningitis (e.g., headache or stiff neck).

      Cohort B: West Nile Virus Fever Cohort:

  • Temperature greater than 38 degrees Celsius as documented by a health care provider.

Exclusion Criteria:

  • Unable to obtain valid informed consent.
  • Alternate explanation (as determined by the investigator) for clinical findings (such as structural brain lesion, cerebrovascular accident, or other infectious disease).
  • Evidence of a microbial organism demonstrable on gram or fungal stain of cerebrospinal fluid (CSF) within four months prior to study entry.
  • Investigator's opinion that patient would be unable to adhere to protocol requirements.
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT00138463

  Hide Study Locations
United States, Alabama
University of Alabama at Birmingham
Birmingham, Alabama, United States, 35294-2050
University of South Alabama Medical Center
Mobile, Alabama, United States, 36617
United States, Arizona
St. Joseph's Hospital and Medical Center
Phoenix, Arizona, United States, 85013
United States, California
Kaiser Permanente South Bay Medical Center
Harbor City, California, United States, 90710
University of Southern California
Los Angeles, California, United States, 90033
University of California Davis Medical Center
Sacramento, California, United States, 95816
Santa Rosa Kaiser Medical
Santa Rosa, California, United States, 95403
United States, Colorado
Kaiser Permanente/Franklin Medical Center
Denver, Colorado, United States, 80205
United States, Idaho
Idaho Falls Infectious Diseases, PLLC
Idaho Falls, Idaho, United States, 83404
United States, Indiana
Indiana University
Indianapolis, Indiana, United States, 46202
United States, Kansas
University of Kansas Medical Center
Kansas City, Kansas, United States, 66160
Via Christi Regional Medical Center
Wichita, Kansas, United States, 67214
United States, Louisiana
Tulane University
New Orleans, Louisiana, United States, 70112
United States, Maryland
Johns Hopkins University
Baltimore, Maryland, United States, 21287
National Institutes of Health
Bethesda, Maryland, United States, 20892-1662
United States, Missouri
Saint Louis University
St. Louis, Missouri, United States, 63110-0250
United States, Montana
Mercury Street Medical Group
Butte, Montana, United States, 59701
United States, Nebraska
Central Nebraska Medical Clinic
Broken Bow, Nebraska, United States, 68822
University of Nebraska Medical Center
Omaha, Nebraska, United States, 68198-7630
VA Medical Center - Omaha
Omaha, Nebraska, United States, 68105
United States, New Jersey
St. George University Clara Maas Medical Center
Belleville, New Jersey, United States, 07109
United States, New Mexico
University of New Mexico
Albuquerque, New Mexico, United States, 87106
United States, Ohio
University of Toledo
Toledo, Ohio, United States, 43614
United States, Rhode Island
Memorial Hospital of RI
Pawtucket, Rhode Island, United States, 02860
United States, Texas
The University of Texas Health Science Center at Houston
Houston, Texas, United States, 77030
The University of Texas Health Science Center
San Antonio, Texas, United States, 78229
United States, Virginia
University of Virginia
Charlottesville, Virginia, United States, 22908
Canada, Manitoba
University of Manitoba
Winnipeg, Manitoba, Canada, R3E 3J7
Sponsors and Collaborators
  More Information

No publications provided by National Institute of Allergy and Infectious Diseases (NIAID)

Additional publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: Director ORA, HHS/NIAID/DMID
ClinicalTrials.gov Identifier: NCT00138463     History of Changes
Other Study ID Numbers: 03-114, CASG 211, N01AI30025C
Study First Received: August 26, 2005
Last Updated: November 3, 2011
Health Authority: Canada: Ethics Review Committee
United States: Federal Government
United States: Institutional Review Board

Keywords provided by National Institute of Allergy and Infectious Diseases (NIAID):
West Nile Virus, Neuroinvasive Disease

Additional relevant MeSH terms:
Virus Diseases
West Nile Fever
Encephalitis, Arbovirus
Arbovirus Infections
Encephalitis, Viral
Central Nervous System Viral Diseases
RNA Virus Infections
Flavivirus Infections
Flaviviridae Infections
Central Nervous System Infections
Central Nervous System Diseases
Nervous System Diseases

ClinicalTrials.gov processed this record on August 18, 2014