Generally parents of HIV-infected children 6 months to 4 years and 5 to 11 years of age generally reported lower mean QoL scores than did parents of uninfected children, although worse psychological functioning was reported for uninfected children. HIV-infected adolescents not receiving antiretroviral treatment had worse health perceptions and symptoms. We found no consistent QoL differences among children receiving different antiretroviral regimens.

We performed a study to determine the duration of survival of HIV-1 in syringes typically used by injectors of illicit drugs (IDUs). We describe the effectiveness of a microculture assay in detecting viable virus in volumes of blood typical of those commonly found inside used syringes. Using this assay and modeling the worse-case situation for syringe sharing, we have recovered viable, proliferating HIV-1 from syringes that have been maintained at room temperature for periods in excess of 4 weeks. The percentage of syringes with viable virus varied with the volume of residual blood and the titer of HIV-1 in the blood. These experiments provide a scientific basis for needle exchange schemes, harm reduction, and other interventions among IDUs that support the nonsharing and removal of used syringes from circulation.

Macrophages are important target cells for human immunodeficiency virus type 1 (HIV-1). The ability of HIV-1 to productively infect macrophages may be influenced by endogenous cytokines that alter the activation state of these cells. In this study, the effect of tumor necrosis factor-alpha/cachectin (TNF alpha), a cytokine with macrophage-activating properties, on HIV-1 replication in primary blood monocyte-derived macrophages was examined. Treatment of macrophages with recombinant human TNF alpha (rTNF alpha), starting before or after HIV-1 infection, consistently enhanced viral production fivefold or greater above control (P less than .01). rTNF alpha was active at low concentrations (0.05-50 ng/ml) and increased the replication of both lymphocyte-tropic (human T lymphotropic virus type IIIB) and macrophage-tropic (human T lymphotropic virus type III BaL) strains of HIV-1. These findings provide additional evidence that TNF alpha may play a role in the pathogenesis of HIV-1 infection by upregulating viral expression in macrophages.

The clinical significance of specimens with low sample-to-cutoff (S/Co) ratios in the Ortho VITROS chemiluminescence assay (CIA) for detection of antibodies to hepatitis C virus (HCV) was evaluated. In one study of 482 CIA-reactive samples, none of the 83 samples with S/Co ratios of <5 was HCV RNA positive. In a subsequent study, 332 samples with S/Co ratios of between 1 and 20 were tested with the recombinant immunoblot assay (RIBA). None of the 163 samples with S/Co ratios of <5 was RIBA positive, 83% were RIBA negative, and 28 samples (18%) were RIBA indeterminate. HCV RNA and/or clinical evidence of hepatitis was not found in the 27 indeterminate cases examined. These results show that over 99% of samples with very low S/Co ratios (<5) have no evidence of HCV infection. Therefore, we suggest that the HCV antibody testing algorithm for the VITROS assay might be modified to eliminate supplemental testing of samples with very low S/Co ratios.Assays for the detection of hepatitis C virus (HCV) antibodies have high false-positive rates, particularly in low-prevalence populations. Therefore, other tests such as recombinant immunoblot assay (RIBA) or HCV RNA PCR are used to confirm positive HCV antibody screening tests. To facilitate usage of the supplemental testing, the Centers for Disease Control and Prevention (CDC) published guidelines that incorporate anti-HCV assay signal-to-cutoff (S/Co) ratios into reflex testing algorithms for HCV antibody testing, in order to provide a more systematic approach for the laboratory diagnosis of HCV and minimize the number of specimens that require supplemental testing (2). Data obtained with three anti-HCV screening assays were used for these recommendations: two enzyme immunoassays (EIAs) (Abbott HCV EIA 2.0 and ORTHO HCV version 3.0 enzyme-linked immunosorbent assay) and one enhanced chemiluminescence immunoassay (CIA) (VITROS anti-HCV assay; Ortho-Clinical Diagnostics).The VITROS anti-HCV CIA has recently been shown to be at least as specific and sensitive as conventional EIAs (7, 9), and use of this CIA has been increasing. However, detailed studies of the CIA S/Co ratio value predictive of a positive supplemental HCV test have been limited (7, 9). The CDC guidelines have suggested reflex supplemental testing for samples with S/C ratios of Ͻ8.0 in the VITROS anti-HCV assay based on the evaluation of a total of 1,326 reactive samples, with only 142 of these specimens having S/Co ratios of Յ7.9 (2).We started using the VITROS anti-HCV assay shortly after its Food and Drug Administration approval in August 2001 and have prospectively applied reflex supplemental testing to all samples with S/Co ratios of between 1.00 and 20.0 in the setting of a population of U.S. veterans (8). The objectives of the present study were (i) to determine the S/Co ratio predictive of detectable HCV RNA; (ii) to evaluate, in samples with low S/Co ratios (between 1 and 20), the relationship between S/Co ratios and the number and types of bands detected by RIBA; (iii) to assess, for samples with i...