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In Vitro Analysis of Myd88-mediated Cellular Immune Response to West Nile Virus Mutant Strain Infection
Published on: November 27, 2014
Risk factors for encephalitis and death from West Nile virus infection
K Murray1, S Baraniuk, M Resnick
1University of Texas, School of Public Health, Houston, TX, USA. Kristy.O.Murray@uth.tmc.edu
Epidemiology and Infection
|May 5, 2006
Summary
Older age, hypertension, and cardiovascular disease increase the risk of West Nile virus (WNV) encephalitis. Black race, renal disease, hepatitis C, and immunosuppression are risk factors for WNV-related death.
Area of Science:
- Neuroscience
- Infectious Diseases
- Epidemiology
Background:
- West Nile virus (WNV) infection can lead to severe neurological complications, including encephalitis.
- Identifying risk factors for WNV encephalitis and mortality is crucial for public health interventions.
Purpose of the Study:
- To identify independent risk factors associated with the development of WNV encephalitis.
- To determine risk factors for mortality among patients hospitalized with WNV infection.
Main Methods:
- A nested case-control study was conducted using retrospective medical chart reviews of 172 WNV cases hospitalized in Houston (2002-2004).
- Multiple logistic regression analysis was employed to identify risk factors for encephalitis and death.
Main Results:
- Independent risk factors for WNV encephalitis included older age (OR 1.1), hypertension (OR 2.9), and cardiovascular disease (OR 3.5).
- Risk factors for WNV-related death, after adjusting for age, were being Black (OR 12.0), chronic renal disease (OR 10.6), hepatitis C virus infection (OR 23.1), and immunosuppression (OR 3.9).
- Homeless individuals were more likely to be hospitalized for WNV infection.
Conclusions:
- Specific demographic and clinical factors significantly increase the risk of developing WNV encephalitis and mortality.
- These findings highlight vulnerable populations and comorbidities that warrant targeted surveillance and preventive strategies for West Nile virus.
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