Molecular Genetics

There are two genetic lineages of the virus in Australia. The first includes the original isolate of MVEV, and that lineage is thought to have caused the epidemics on the east coast (including part of the 1974 epidemic) after which it disappeared. The second lineage appeared in the north of WA in 1969 and was responsible for part of the 1974 outbreak. Since then this lineage has been responsible for nearly all MVEV activity in Australia, with less than 2% sequence divergence across time and geographic areas in the NS5 region.[9] However, recent data based on the E gene sequence do indicate that there are minor strain variations over time, but not across different geographical areas (Johansen, C.A., personal communication). This is consistent with there being a single enzootic focus, most likely in the north of WA, which is the source of MVEV throughout Australia, and that evolution of the virus occurs within that enzootic focus.

One early isolate (OR156) from the north of WA contained additional uridine residues resembling two PNG isolates[22] from 1956 and 1966, suggesting that other

Table 2 Yield of diagnostic tests for MVE encephalitis for human cases tested at the Western Australian Centre for Pathology and Medical Research between 1978 and 2001

Proportion positive for samples collected at the following days after onset of symptoms

Serum IgM 6/9 12/14 14/14 32/37

IgM in serum and cerebrospinal fluid (CSF) detected by indirect immunflourescent antibody method. Polymerase chain reaction (PCR) was a nested reverse transcription PCR directed at 3' noncoding region sequence.

lineages exist in PNG and possibly the eastern Indonesian archipelago. The E gene sequence data show that recent PNG isolates cluster with isolates from the Kimberley region of WA prior to 1984, but are different from the more recent Australian isolates. Therefore, there may be regular movement of the virus between the north of WA and PNG. Little is known about the distribution of MVEV in PNG and its role in human disease.

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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