All current diagnostic PCRs target the S RNA segment (Table 3). For some Lassa virus PCRs, clinical evaluation data are available showing 85% and 100% sensitivity (Table 3, PCR 1 and 3). These studies also demonstrate that virus is detectable beginning at least from day 3 of fever. Quantitative real-time PCR was established (Table 3, PCR 2) and used to monitor virus RNA concentrations during the course of disease in two cases of Lassa fever.[6,23] The RNA concentrations in serum of these patients were 5 x 102-2 x 106-fold above the detection limit of the assay. Extensive sequence information for the S RNA segment of Lassa virus has recently become available and reveals considerable genetic variability of the virus.[22'24'25] In light of these new sequences, some PCR primers, which had been designed mainly on the basis of isolates from Guinea, Sierra Leone, or Liberia, require revision (Table 3, PCR 3-6).

PCR assays are published for the New World arenavirus Junin (Table 3, PCR 7 and 8). Clinical sensitivity of the combination of the two different Junin PCRs was 98%.

A PCR predictably amplifying any member of the Arenaviridae has been developed by targeting the highly conserved termini of the S RNA segment.[22] Although this PCR amplifies the whole 3.4-kb S RNA, it was able to detect Lassa virus RNA in clinical samples. The L RNA segment of arenaviruses contains highly conserved

Table 3 Arenavirus PCR
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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