The HIV Characterisation Laboratory has both diagnostic and research
and development roles.
In the diagnostic laboratory, quantitative HIV-1 RNA testing is
used to monitor disease progression, to help determine when to
initiate treatment with antiretroviral drugs and to monitor the
virological response to these drugs. Qualitative HIV DNA detection
is also available and may be used as an adjunct to serological
testing when recent HIV infection, including neonatal infection,
is suspected.
Sequencing (genotyping) of regions of the genome can also be performed
when failure of therapy is thought to be associated with the development
of drug resistance. Currently the sequences amplified for this
purpose are the protease, reverse transcriptase and transmembrane
protein coding regions.
Australian HIV testing laboratories assesses the impact of sequence
changes on susceptibility to the current drugs using a rules based
algorithm (the
CREST algorithm). The laboratory supplies the HIV subtype
on each sequence amplified.
The HIV Characterisation Laboratory also has an active research
and development program. A quantitative HIV-2 RNA assay has been
recently developed to help follow disease progression in the small
number of Australian residents currently infected with this virus.
A major area of interest is the transmission of drug resistant
virus and the subsequent response to antiretroviral therapy of
individuals infected with these viruses. The laboratory also has
a significant collaboration with the National Centre for HIV Epidemiology
and Clinical Research, acting as a testing site for this organisation
and performing studies on cohorts of patients involved in its
clinical trials (Middleton,
2001 ; Birch,
2003).
