HIV-1 CRF 02 AG polymerase genes in Southern Ghana are mosaics of different 02 AG strains and the protease gene cannot infer subtypes

<p>Abstract</p> <p>Background</p> <p>Little is known about the detailed phylogeny relationships of CRF 02_AG HIV-1 polymerase genes in Ghana. The use of the protease gene of HIV-1 for subtyping has shown conflicting results.</p> <p>Methods</p> <p>The partial polymerase gene sequences of 25 HIV-1 strains obtained with Viroseq reagents were aligned with reference subtypes and alignments trimmed to a 300 bp protease, 661 bp and 1005 reverse transcriptase sequence alignments. Phylogenetic relationships of these alignments were determined with the Neighbour-Joining method using 1000 replicates and recombination patterns determined for the sequences with RIP 3.0 in the HIV sequence database.</p> <p>Results</p> <p>Unlike the other alignments, the protease gene had nodes with bootstrap values < 100% for repeat control sequences. Majority of the CRF 02_AG sequences from Ghana were made up of fragments of several strains of CRF 02_AG/AG strains. The protease gene alone is not suitable for phylogenetic analysis.</p> <p>Conclusion</p> <p>The polymerase genes of HIV-1 strains from Ghana are made up of recombinants of several CRF 02_AG strains from Ghana, Senegal and Cameroon, but the clinical implications are unknown. Using the HIV-1 protease gene for subtyping will not infer subtypes correctly.</p

Hepatitis B virus surface antigen and antibody markers in children at a major paediatric hospital after the pentavalent DTP-HBV-Hib vaccination

Objectives: The knowledge about outcomes of infant vaccination against HBV infections using the DPT-HepB-Hib vaccine in Ghana is limited. This study therefore investigated the levels of immunity to HBV among children who received the DPT-HepB-Hib vaccine and HBsAg carriage in non-responders. Correlates for non-response or poor response were also investigated.Methods: Cross-sectional study. A major paediatric hospital in Accra. Four hundred and twenty four children between the ages of 5 to 32 months who had completed the full vaccination schedule for the DPT-HepB-Hib vaccine.Results: Of the 424 children, 358 (84.4%) developed anti-HBs while 340 (80.2%) developed ≥10 mIU/ml anti-HBs (sero-protection) and 3 had HBsAg. A binary logistic regression analysis showed that younger children were associated with sero-conversion (p=.022) and sero-protection (p=.021). For anti-HBs titres ≥100 mIU/ml age was a weaker but significant contributor (p=.041), as compared to the number of vaccines from different manufacturers the child used (p=.028). The mean age of those who used a single type of vaccine was higher (14.75 ± 6.056 months; n=268) than those who used vaccines from two or more manufacturers (11.96 ± 4.645 months; n=156), p= &lt;.001 (CI: -3.897 – 1.688), an indication that efforts to procure vaccine from same source when it was initially introduced are waning.Conclusions: There is still a residual possibility of infection with HBV in spite of infant vaccination. In the light of possible loss of anamnestic response over time, there is the need to consider a birth dose for HBV vaccination for all neonates or booster dose for infants who may not have received the vaccine at birth. Using vaccines from a single manufacturer is recommended.Funding: None declaredKeywords: Infant; hepatitis B virus; vaccination; surface antigen; surface antibod

Short-term treatment outcomes in human immunodeficiency virus type-1 and hepatitis B virus co-infections

BACKGROUND: Co-infection of HIV with HBV is common in West Africa but little information is available on the effects of HBV on short-term therapy for HIV patients. A 28 day longitudinal study was conducted to examine short-term antiretroviral therapy (ART) outcomes in HIV infected individuals with HBV co-infection. METHODS: Plasma from 18 HIV infected individuals co-infected with HBV and matched controls with only HIV infection were obtained at initiation, and 7 and 28 days after ART. HIV-1 viral load changes were monitored. Clinical and demographic data were also obtained from patient folders, and HIV-1 drug resistance mutation and subtype analysis performed. RESULTS: The presence of HBV co-infection did not significantly affect HIV-1 viral load changes within 7 or 28 days. The CD4(+) counts on the other hand of patients significantly affected the magnitude of HIV-1 viral load decline after 7 days (ρ = −0.441, p = 0.040), while the pre-ART HIV-1 VL (ρ = 0.844, p = <0.001) and sex (U = 19.0, p = 0.020) also determined HIV-1 viral load outcomes after 28 days of ART. Even though the geometric sensitivity score of HIV-1 strains were influenced by the HIV-1 subtypes (U = 56.00; p = 0.036), it was not a confounder for ART outcomes. CONCLUSIONS: There may be the need to consider the confounder effects of sex, pre-ART CD4(+), and pre-ART HIV-1 viral load in the discourse on HIV and HBV co-infection

Web interface-supported transmission risk assessment and cost-effectiveness analysis of postdonation screening:a global model applied to Ghana, Thailand, and the Netherlands

BACKGROUND: The goal of our research was to actively involve decision makers in the economic assessment of screening strategies in their region. This study attempted to accomplish this by providing an easy-to-use Web interface at http://www.bloodsafety.info that allows decision makers to adapt this model to local conditions. STUDY DESIGN AND METHODS: The cost-effectiveness was compared of 1) adding antigen screening to antibody screening for hepatitis C virus (HCV) and human immunodeficiency virus (HIV); 2) adding nucleic acid amplification testing (NAT) on hepatitis B virus (HBV), HCV, and HIV in minipool ( pool of 6 [MP6] and 24 [MP24]) to antibody screening and hepatitis B surface antigen ( HBsAg) screening; and 3) individual-donation NAT on HBV, HCV, and HIV to antibody screening and HBsAg screening for Ghana, Thailand, and the Netherlands. RESULTS: The combination of HCV antibody-antigen combination (combo) and HIV combo added to antibody screening in Ghana and Thailand was cost-effective according to the WHO criteria. MP24-NAT screening in Ghana was also cost-effective. MP24-NAT on HBV, HCV, and HIV was not cost-effective compared to the other screening strategies evaluated for the Netherlands. Large regional differences in cost-effectiveness were found for Thailand. CONCLUSION: The young transfusion recipient population of Ghana in combination with a high risk of viral transmission yields better cost-effectiveness for additional tests. The advanced age of the transfused population of the Netherlands and a small risk of viral transmission gives poor cost-effectiveness for more sensitive screening techniques. It was demonstrated that a global health economic model combined with a Web interface can provide easy access to risk assessment and cost-effectiveness analysis

Effectiveness of first-line antiretroviral therapy and correlates of longitudinal changes in CD4 and viral load among HIV-infected children in Ghana

Background: Antiretroviral therapy (ART) scale-up in resource-limited countries, with limited capacity for CD4 and HIV viral load monitoring, presents a unique challenge. We determined the effectiveness of first-line ART in a real world pediatric HIV clinic and explored associations between readily obtainable patient data and the trajectories of change in CD4 count and HIV viral load. Methods: We performed a longitudinal study of a cohort of HIV-infected children initiating ART at the Korle-Bu Teaching Hospital Pediatric HIV clinic in Accra, Ghana, aged 0-13 years from 2009-2012. CD4 and viral load testing were done every 4 to 6 months and genotypic resistance testing was performed for children failing therapy. A mixed linear modeling approach, combining fixed and random subject effects, was employed for data analysis. Results: Ninety HIV-infected children aged 0 to 13 years initiating ART were enrolled. The effectiveness of first-line regimen among study participants was 83.3%, based on WHO criteria for virologic failure. Fifteen of the 90 (16.7%) children met the criteria for virologic treatment failure after at least 24 weeks on ART. Sixty-seven percent virologic failures harbored viruses with ≥ 1 drug resistant mutations (DRMs); M184V/K103N was the predominant resistance pathway. Age at initiation of therapy, child’s gender, having a parent as a primary care giver, severity of illness, and type of regimen were associated with treatment outcomes. Conclusions: First-line ART regimens were effective and well tolerated. We identified predictors of the trajectories of change in CD4 and viral load to inform targeted laboratory monitoring of ART among HIV-infected children in resource-limited countries

Cost-effectiveness of HIV screening of blood donations in Accra (Ghana)

AbstractObjectivesAreas with high HIV-incidence rates compared to the developed world may benefit from additional testing in blood banks and may show more favorable cost-effectiveness ratios. We evaluated the cost-effectiveness of adding p24 antigen, mini pool nucleic acid amplification testing (MP-NAT), or individual donation NAT (ID-NAT) to the HIV-antibody screening at the Korle Bu Teaching Hospital (Accra, Ghana), where currently only HIV-antibody screening is undertaken.MethodsThe residual risk of HIV transmission was derived from blood donations to the blood bank of the Korle Bu Teaching Hospital in 2004. Remaining life expectancies of patients receiving blood transfusion were estimated using the World Health Organization life expectancies. Cost-effectiveness ratios for adding the tests to HIV-antibody screening only were determined using a decision tree model and a Markov model for HIV.ResultsThe prevalence of HIV was estimated at 1.51% in 18,714 donations during 2004. The incremental cost per disability-adjusted life-year (DALY) averted was US$1237 for p24 antigen, US$3142 for MP-NAT and US$7695 compared to the next least expensive strategy. HIV-antibody screening itself was cost-saving compared to no screening at all, gaining US$73.85 and averting 0.86 DALY per transfused patient. Up to a willingness-to-pay of US$2736 per DALY averted, HIV-antibody screening without additional testing was the most cost-effective strategy. Over a willingness-to-pay of US$11,828 per DALY averted, ID-NAT was significantly more cost-effective than the other strategies.ConclusionsAdding p24 antigen, MP-NAT, or ID-NAT to the current antibody screening cannot be regarded as a cost-effective health-care intervention for Ghana

Misclassification of recent HIV-1 seroconversion in sub-Saharan Africa using the sensitive/less sensitive technique

Abstract Background In resource-limited settings where HIV-1 is endemic, there is a need for simple, inexpensive but effective rapid methods for detecting recent infections and estimating incidence for the purposes of surveillance and management. We sort to determine possible reasons for reported misclassifications of recent HIV-1 seroconversion as determined with the S/LS assay in sub-Saharan Africa. Findings We used the modified Determine HIV-1/2 sensitive/less sensitive method for determining recent HIV-1 seroconversion to determine recent infections among ELISA repeat HIV-1 positive samples from blood donors. Furthermore, HIV-1 seropositivity was confirmed using a line immunoassay and the results used to validate the performance of the modified Determine HIV-1/2 S/LS assay. The results confirmed reported misclassifications of recent HIV-1 seroconversion in sub-Saharan Africa. It was noted that, lack of confirmation of HIV-1 seropositivity in suspected cases of HIV-1 contributed to misclassifications. Conclusions It was concluded that, with confirmation of HIV-1 seropositivity, the modified Determine HIV-1/2 S/LS assay will be a rapid and cost effective method for determining HIV-1 recent infections and estimating incidence in resource-limited settings. The need for detailed studies to validate simple methods for determining recent HIV-1 infections is emphasized.</p

CYP2B6, CYP2A6 and UGT2B7 genetic polymorphisms are predictors of efavirenz mid-dose concentration in HIV-infected patients

UDP-glucuronosyltransferase (UGT) 2B7 was recently identified as the main enzyme mediating efavirenz N-glucuronidation. In this study, we determined whether selected UGT2B7 polymorphisms could be used to enhance the prediction of efavirenz plasma concentrations from CYP2B6 and CYP2A6 genotypes. Mid-dose efavirenz plasma concentrations were determined in 94 HIV-infected Ghanaian patients at 2-8 weeks of antiretroviral therapy. CYP2B6 and CYP2A6 genotypes had been previously reported. UGT2B7 exon 2 single-nucleotide polymorphisms (SNPs) c.735A>G (UGT2B7*1c; rs28365062) and c.802C>T (H268Y; UGT2B7*2; rs7439366) were determined by direct sequencing with UGT2B7*1a defined as the reference allele. Relationships between efavirenz plasma concentrations, demographic variables and genotypes were evaluated by univariate and multivariate statistical approaches. The mean (+/-SD) mid-dose efavirenz plasma concentration was 3218 (+/-3905) ng/ml with coefficient of variation of 121%. Independent predictors of efavirenz concentration included CYP2B6 c.516TT genotype (4030 ng/ml increase; 95% confidence interval 2882-5505 ng/ml, P < 0.001), UGT2B7*1a carrier status (475 ng/ml increase; 95% confidence interval 138-899 ng/ml, P = 0.004) and CYP2A6*9 and/or *17 carrier status (372 ng/ml increase; 95% confidence interval 74-742 ng/ml, P = 0.013). Overall, CYP2B6 c.516TT genotype, UGT2B7*1a carrier status and CYP2A6*9 or *17 carrier status accounted for 45.2, 10.1 and 8.6% of the total variance, respectively. Our findings demonstrate independent effects of CYP2A6 and UGT2B7 genetic variation on efavirenz disposition beyond that of the CYP2B6 polymorphisms. The development and testing of a pharmacogenetic algorithm for estimating the appropriate dose of efavirenz should incorporate genotypic data from both the oxidative and glucuronidation pathways