Field application studies of rapid HIV tests (RHTs) have provided valuable insight into acceptability and performance or RHTs, particularly specificity. However, field studies are unable to assess test sensitivity and limit of detection of different RHTs. Laboratory evaluation by testing larger numbers of specimens with acute and confirmed HIV infection is required.
We evaluated six candidate RHTs and conventional diagnostic laboratory assays on panels of well characterised serum and plasma samples. Samples from 50 antiretroviral treatment naïve individuals were tested with a HIV incidence ELISA and categorised as recent infection (within 155 days) (n=25) or established HIV infection (>155 days) (n=25). A further 59 samples from individuals with laboratory evidence of acute HIV infection (reactive fourth generation conventional HIV-1/2 Ag/Ab test, detectable HIV-1 p24 antigen or nucleic acid, negative or evolving HIV western blot) were used to assess test sensitivity in terms of limit of detection. Of the 59 acutely infected individuals, 38 had follow-up samples available (mean 6.89 days, range 2-7 days) from the index sample. A further 50 samples collected from individuals found to be seronegative by the conventional HIV-1/2 Ab/Ag 4th generation laboratory screening test were included to assess specificity.
Compared with the conventional laboratory test algorithm including Abbott Architect HIV 1/2 Ag/Ab combo , the sensitivity of the six rapid tests in acute infection was: Alere HIV-1/2 Ag/Ab Combo 87.5%; Alere HIV-1/2 Antibody 84.1%; Trinity Uni-Gold HIV-1/2 Antibody 76.3%; Insti HIV-1/2 Antibody 72.5%; Biorad Multispot HIV-1/2 Antibody 72.5%; and Orasure Oraquick HIV-1/2 Antibody 61.7%. Sensitivity in patients with known HIV infection for the rapid tests was 100%, except for the Orasure Oraquick HIV-1/2 Antibody (96.1%). Specificity for the rapid tests was 100%, except for the Orasure Oraquick HIV-1/2 Antibody (98.0%).
These results confirm that RHT’s are less sensitive than conventional laboratory tests in detection of acute HIV infection. The introduction of rapid tests at the point of care have been shown to be acceptable to men who have sex with men and provides an additional tool to potentially increase testing. However, our evaluation highlights systems are needed to ensure that men seeking RHTs who have a recent risk exposure, also have conventional HIV laboratory tests.
REACH was a collaborative research and practice initiative to develop evidence building frameworks, capacity, tools and resources with the Victorian HIV community partnership.
HIV disease is associated with chronic inflammation and activation of the innate immune system. This state, as measured using plasma markers of inflammation, persists following suppression of HIV viremia using antiretroviral therapy, and may increase risk of non-AIDS co-morbidities. The causes of innate immune activation in the setting of virological suppression are unclear. Natural killer (NK) cells are innate immune cells that kill virus-infected and transformed cells without prior sensitization. We have shown that NK cells are activated both phenotypically (elevated expression of HLA-DR) and functionally (increased spontaneous degranulation measured by CD107a surface expression) in virologically suppressed (VS) HIV+ individuals. NK cells also lose expression of CD16, the receptor which mediates antibody-dependent cellular cytotoxicity.
Regular HIV testing is recommended in men who take sexual risks. We assessed the relationship between perceived barriers to HIV testing, and frequency of testing among men who engaged in unprotected anal intercourse with casual partners (UAIC), to inform HIV testing strategies.
The majority of HIV diagnoses including delayed diagnoses in Australia occur among men who report homosexual contact – hereafter called gay and bisexual men (GBM). Delayed diagnosis is strongly associated with increased HIV-related mortality and morbidity. People who are unaware of their HIV-positive status may also be unwittingly transmitting HIV. We assessed trends in delayed HIV diagnoses among GBM in Australia.
HIV-associated leishmaniasis, endemic in the Mediterranean basin is a growing problem in India, Brazil and East Africa. Despite surviving for than 20 years, the clinical course of our visceral-leishmania (VL)-HIV co-infected patient illustrates several management challenges including diagnosis, speciation and drug resistance; monitoring burden of disease; access to and use of VL-treatments; end-organ toxicity and the combined immunosuppressive effects of HIV-VL.
Adherence to combination antiretroviral therapy (cART ) plays an important role on treatment outcomes. The TREAT Asia Studies to Evaluate Resistance – Monitoring Cohort Study (TASER-M) collects patients’ adherence based on a Visual Analogue Scale. The aim of this analysis was to assess the rates of, and factors associated with, suboptimal adherence in the first 24 months of initial cART in Asian patients.
Early first sexual intercourse has been proposed as an important marker of later sexual and reproductive health. Discussions of what constitutes early sexual debut in this context, however, have been limited.