Risk factors and time-trends of cytomegalovirus (CMV), syphilis, toxoplasmosis and viral hepatitis infection and seroprevalence in human immunodeficiency virus (HIV) infected patients

<p><b>INTRODUCTION</b>Chronic bacterial, viral and parasitic infections contribute to the morbidity and mortality associated with human immunodeficiency virus (HIV) infection. This study investigated risk factors and time-trends of the seroprevalence of cytomegalovirus (CMV), toxoplasmosis and hepatitis A total antibody; and co-infection with syphilis, hepatitis B and hepatitis C among newly diagnosed HIV individuals in Singapore.</p><p><b>MATERIALS AND METHODS</b>This was a cross-sectional study. A random sample of 50% of HIV infected patients who visited the Communicable Disease Centre (CDC), Singapore for first-time care from January 2006 to December 2011 were analysed.</p><p><b>RESULTS</b>Among the 793 study subjects, 93.4% were male; 77.9% of them were of Chinese ethnicity; mean age at HIV diagnosis was 41.4 years; and the mean baseline CD4+ T-cell count was 222 cells/mm³. The prevalence of sero-reactivity for CMV was 96.8%; hepatitis A: 40.9%; and toxoplasmosis: 23.7%. Co-infection with syphilis was identified in 12.3%; hepatitis B: 8.1%; and hepatitis C: 2%. Among those co-infected with hepatitis C, 73.3% of them were intravenous drug user (IVDU). Syphilis co-infection was significantly more common among men who have sex with men (MSM) (multivariate OR: 2.53, 95% CI, 1.31 to 4.90, P = 0.006).</p><p><b>CONCLUSION</b>This study described the baseline rates of HIV co-infection with syphilis, hepatitis B and C in Singapore, and sero-reactivity to CMV, toxoplasmosis and hepatitis A. The increased rates compared to the general population may have important consequences for disease progression, response to antiretroviral treatment and long-term general health.</p>

Clinical evaluation of an in-house human immunodeficiency virus (HIV) genotyping assay for the detection of drug resistance mutations in HIV-1 infected patients in Singapore

<p><b>INTRODUCTION</b>Human immunodeficiency virus type 1 (HIV-1) genotyping resistance test (GRT) is essential for monitoring HIV-1 drug resistance mutations (DRMs). High cost and HIV-1 genetic variability are challenges to assay availability in Singapore. An in-house Sanger sequencing-based GRT method was developed at the Communicable Disease Centre (CDC), Singapore's HIV national treatment reference centre for both subtype B and non-subtype B HIV-1.</p><p><b>MATERIALS AND METHODS</b>The in-house GRT sequenced the fi rst 99 codons of protease (PR) and 244 codons of reverse transcriptase (RT) in the pol gene. The results were compared with the Food and Drug Administration (FDA)-approved ViroSeq™ HIV-1 Genotyping System.</p><p><b>RESULTS</b>Subtype assignment for the 46 samples were as follows: 31 (67.4%) CRF01_AE, 14 (30.5%) subtype B and 1 (2.1%) subtype C. All 46 samples had viral load of ≥500 copies/mL, and were successfully amplified by the in-house primer sets. Compared to the ViroSeq™ test, our in-house assay showed drug-resistance conferring codon concordance of 99.9% at PR and 98.9% at RT, and partial concordance of 0.1% at PR and 1.1% at RT. No discordant result was observed.</p><p><b>CONCLUSION</b>The assay successfully identified DRMs in both subtype AE and B, making it suitable for the efficient treatment monitoring in genetically diverse population. At less than half of the running cost compared to the ViroSeq™ assay, the broadly sensitive in-house assay could serve as a useful addition to the currently limited HIV genotyping assay options for resource-limited settings, thereby enhancing the DRM surveillance and monitoring in the region.</p>

Healthcare workers and HIV health issues

Should healthcare workers (HCWs) be routinely tested for HIV? The authors reviewed the literature on the risk and incidence of HIV transmission from HCW to patients and offer recommendations for HIV testing in HCWs in Singapore. Management of HCWs who are tested seropositive for HIV infection is also discussed in this paper.