Karen L Roos1. 1. Department of Neurology, Indiana University School of Medicine, Indianapolis, Indiana, USA. kroos@iupui.edu
Abstract
PURPOSE OF REVIEW: This article will review the recent experience with West Nile virus encephalitis and myelitis. RECENT FINDINGS: In the summer of 2003, the majority of cases of West Nile virus infection in the United States were reported from the western states. The transmission of West Nile virus through blood transfusion and organ transplantation was recognized and blood collection agencies implemented West Nile virus nucleic acid-amplification tests to identify infected donors. Intrauterine transmission of West Nile virus infection was reported. The identification of West Nile virus immunoglobulin M in cerebrospinal fluid is the recommended test to document central nervous system infection, but this test may not be positive in spinal fluid collected less than 8 days after the onset of symptoms. Serial samples of cerebrospinal fluid may be required to identify the antibodies. A clinical trial got underway to evaluate the efficacy of human immunoglobulin with high titers of antibodies to West Nile virus in the therapy of West Nile virus encephalitis and myelitis. SUMMARY: In the summer of 2003, the majority of cases of West Nile virus infection in the United States were reported from states west of the Mississippi river. The identification of West Nile virus IgM in CSF is the recommended test to document CNS infection. A single serum antibody titer is an unreliable test of recent infection.
PURPOSE OF REVIEW: This article will review the recent experience with West Nile virus encephalitis and myelitis. RECENT FINDINGS: In the summer of 2003, the majority of cases of West Nile virus infection in the United States were reported from the western states. The transmission of West Nile virus through blood transfusion and organ transplantation was recognized and blood collection agencies implemented West Nile virus nucleic acid-amplification tests to identify infected donors. Intrauterine transmission of West Nile virus infection was reported. The identification of West Nile virus immunoglobulin M in cerebrospinal fluid is the recommended test to document central nervous system infection, but this test may not be positive in spinal fluid collected less than 8 days after the onset of symptoms. Serial samples of cerebrospinal fluid may be required to identify the antibodies. A clinical trial got underway to evaluate the efficacy of human immunoglobulin with high titers of antibodies to West Nile virus in the therapy of West Nile virus encephalitis and myelitis. SUMMARY: In the summer of 2003, the majority of cases of West Nile virus infection in the United States were reported from states west of the Mississippi river. The identification of West Nile virus IgM in CSF is the recommended test to document CNS infection. A single serum antibody titer is an unreliable test of recent infection.