Diagnosis

The virus has rarely been cultured from human material, and the viremia is likely to be short-lived. Therefore, while MVEV will grow in mosquito cell lines and suckling mouse brain, cell culture methods have not been useful in diagnosis of infections.

Most diagnoses are made serologically. Paired sera taken in the first few days after onset and 2-3 weeks later will show rising antibody by HI test, EIA, or IFA, although the HI is the least sensitive and may rise late or, rarely, not at all. IgM is present in nearly all patients at the time of presentation. In the WA series, IgM was detected in serum in most cases within 1 week of onset of illness, and in all cases beyond that, whereas CSF IgM was positive in about 75% (Table 2). Following infection serum IgM may remain positive for months, so that the presence of IgM, in the absence of virus detection of a rise in IgG, can only be taken as possible evidence of recent infection.

Antibody will cross-react with other flaviviruses, particularly Kunjin and JE which may also cause encephalitis in the same geographical area. The specificity of antibody can be determined by neutralization tests or epitope-blocking EIA.[23] However, even with specific tests, misleading results may occur in patients who have had a previous flavivirus infection. In these circumstances, antibody to the previously infecting flavivirus may rise before antibody to the currently infecting virus.[24]

Detection of MVEV-RNA in CSF can be achieved using a nested PCR directed to the 3' untranslated region of the genome, and it is a useful investigation where early samples are available at a time when serology may still be negative (Table 2).

Getting Started With Dumbbells

Getting Started With Dumbbells

The use of dumbbells gives you a much more comprehensive strengthening effect because the workout engages your stabilizer muscles, in addition to the muscle you may be pin-pointing. Without all of the belts and artificial stabilizers of a machine, you also engage your core muscles, which are your body's natural stabilizers.

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