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Item Pitfalls in diagnosis of hepatitis B virus infection among adults Nigerians(2009) Ola, S. O.; Otegbayo, J. A.; Yakubu, A.; Aje, A. O.; Odaibo, G. N.; Shokunbi, W."OBJECTIVE:Hepatitis B virus infection is common in Nigerians and its diagnosis is necessary for effective treatment and eradication. This study is aimed at highlighting the serological factors jeopardizing the diagnosis and treatment of the infection among Nigerians adults. PATIENTS AND METHODS:Three studies were carried out. The first study involved 56 Nigerian adults and it compared the assay of HBsAg by Haemagulation Method (HMA) with Enzyme linked immunoassay (ELISA). The second study was a comparison of Glaxo Welcome HB rapid test(GWHB) with ELISA in sero-assay of HBsAg and HBeAg among 25 Nigerian subjects while the third study was on the assay of the sera of HBsAg positive patients for HBeAg and anti-HBe in forty two Nigerian patients by ELISA. RESULTS:The sero - prevalence rates of HBsAg were 41.8% and 61.8% by HM and ELISA respectively with false HBsAg sero-positives and sero-negatives by HM of 5.4% and 25.5% respectively. Similarly, there was sero-detection of HBsAg in 84% and 80% by ELISA and GWHB respectively in 25 Nigerian adults. In addition, 19% and 64% of the 42 patients with HBsAg sero-positivity were also positive for HBeAg and anti-HBe respectively, while 31% of the patients were both HBeAg and anti-HBe sero-negative. CONCLUSION:Sero-diagnosis of HBsAg and other serological markers of infectivity in patients with HBV should be carried out by ELISA rather than HMA among adult Nigerians. Furthermore, high infectivity of the virus abounds among Nigerian with HBV infection."Item A new affordable flow cytometry based method to measure HIV-1 viral load(International Society for Advancement of Cytometry, 2009) Greve, B.; Weidner, J.; Cassens, U.; Odaibo, G.; Olaleye, D.; Sibrowski, W.; Reichelt, D.; Nasadala, I.; Gohde.Most commercially available assays for diagnosis of HIV infection have shown shortcomings in the detection and quantification of rare genotypes of the virus. Most of the assays do not detect subtype O (outlier) and/or N (nonmajor, nonoutlier) or new circulating recombinant forms (CRFs), which are becoming more important in sub-Saharan Africa. Furthermore, the commonly available tests require costly measuring devices and expensive test kits, which are not easily affordable for developing countries. This study was designed to explore solutions to the problem of viral load assays in developing countries. Two forward primers, digoxygenin (DIG) and dinitrophenol (DNP) labeled, and one biotin (BIO) labeled reverse primer were used to amplify both, the HIV-1-5'LTR (long terminal repeat) region and an internal standard sequence. The two polymerase chain reaction (PCR)-products were captured by anti-DIG and anti-DNP antibody coated microparticles. Flow cytometric analyses were carried out after labeling with streptavidin-R-phycoerythrine. The primer system used recognized all HIV-1 subtypes. A coamplified internal standard warranted the functionality of the PCR and allows reproducible viral load measurements. Two drawbacks of current viral load measurements are overcome by the flow cytometry based test described hereof. First, all known worldwide relevant HIV-1 subtypes including subtypes O, N, and new CRFs are quantifiable with high sensitivity (50 to >1 x 10(6) copies per PCR). Second, the cost per test can be reduced to less than 12 US$ instead of the current 50-100 US$. Additionally, the test described in this report offers the possibility to perform complete monitoring program (CD4 T-cell count, CD4% and viral load) for the first time, with the same device for HIV-infected persons.Item Occult HBV infection among a cohort of Nigerian adults(Creative Commons Attibution, 2009) Ola, S. O.; Otegbayo, J. A.; Odaibo, G. N.; Olaleye, D. O.; Summerton, C. B.; Bamgboye, E. A."OBJECTIVE:To determine markers of HBV infection and detect the presence of its occult infection in serum of a cohort of adult Nigerians. METHODOLOGY:The study involved 28 adult Nigerians with viral hepatitis (Group 1) and 28 apparently healthy adult Nigerians as controls (Group 2). Their sera were assayed for HBsAg, HBeAg, anti-HBe, anti-HBc, anti-HBs, and anti-HCV, while HBV DNA was determined in 15 patients with chronic hepatitis. Significance of differences between the patients and control subjects was assessed using Chi-square test at a 95% confidence level. RESULTS:Sero-detection of HBsAg, HBeAg, anti-HBe and anti-HBc was higher among the patients compared to the controls. HBV infection was diagnosed by HBsAg (89%) and a duo of HBsAg and anti-HBc (100%) among the patients. Similarly, eleven and four types of different patterns of HBV markers were observed among the respective groups. Anti-HBe (9.5%), anti-HBc (14.3%), and anti-HBs (9.5%) were detected among all the subjects who were sero-negative for HBsAg. HBV DNA was also detected in 86.7% of the 15 patients with chronic hepatitis, while occult HBV infection was observed in 7.2% of the patients and none (0%) of the controls, p < 0.05. Furthermore, HCV infection occurred among subjects with all the different patterns of HBV markers, except those with occult HBV infection and natural immunity to HBV. CONCLUSION:This study shows that occult HBV infection is present among Nigerian adults and determination of HBsAg, anti-HBc, anti-HBe, and HBV DNA will assist in its detection."Item Detection of HIV antigen and cDNA among antibody-negative blood samples in Nigeria(Elsevier Ltd, 2008) Odaibo, G. N.; Taiwo, A.; Aken'Ova, Y. A.; Olaleye, D. O.In developing countries as many as 50% of patients for whom a transfusion is indicated are at risk of dying immediately if transfusion is withheld. It is therefore important that blood transfusion is made as safe as possible. This study was designed to assess the safety of blood transfusion in two large blood banks in Ibadan, Nigeria. Aliquots of 250 samples already screened and passed as negative for HIV-1 and -2 were collected from each of the blood banks. Samples were tested for the presence of HIV-1 antigen (ELAVIA Ag I) and the antigen-positive samples tested for the presence of specific HIV-1 antibodies by Western blot (BioRad, France). All antigen-positive samples were also subjected to PCR. HIV-1 antigen was detected in 6 (1.2%) of the 500 samples, of which 4 (0.8%) and 3 (0.6%) were Western blot-indeterminate and PCR-positive, respectively. Transfusion of HIV-contaminated blood may be contributing significantly to the spread of the virus in Nigeria. There is therefore an urgent need for an organized blood-banking system with facilities for more sensitive assays for the detection of HIV in blood to prevent transmission through transfusion.Item Nigeria butchers and hepatitis B virus infection(2008) Ola, S. O.; Otegbayo, J. A.; Yakubu, A.; Odaibo, G. N.; Olaleye, D. O.Various target groups have been identified in Nigeria for studying the prevalence of hepatitis B virus infection; however there is no information on its prevalence among workers in slaughter houses. This study determined the seroprevalence of hepatitis B virus infection in Nigerian butchers at Ibadan, and comprised 360 healthy Nigerian adult subjects (180 butchers, 180 traders as controls) selected by multistage stratified sampling. A questionnaire was used to collect relevant information and included points about risk behaviour. ELISA was used to detect the hepatitis B surface antigen in the serum; the seroprevalence rate in butchers and controls was 9.4% and 3.3%, respectively (p<0.05). Risk behaviour was seen more commonly in butchers than in controls. The presence of hepatitis B surface antigen in the serum was not related to the duration of occupational exposure or the number of partners. In summary, butchers comprise a high-risk occupational group for exposure to hepatitis B virus infection. We conclude that routine screening for parenterally acquired infections in this group is thus necessary in order to identify those who will require treatment and immunisation, especially against hepatitis B virus infection.Item Prevalence of hepatitis B virus and C seropositivity in a Nigerian cohort of HIV-infected patients(2008) Otegbayo, J. A.; Taiwo, B. O.; Akingbola, T. S.; Odaibo, G. N.; Adedapo, K. S.; Penugonda, S.; Adewole, I. F.; Olaleye, D. O.; Murphy, R.; Kanki, P."INTRODUCTION:The clinical and public health implications of the convergence of the human immunodeficiency virus (HIV) epidemic and chronic viral hepatitis in sub-Saharan Africa are poorly understood. This study was designed to determine the seroprevalence of hepatitis B virus (HBV) and hepatitis C virus (HCV), and the impact of co-infection on baseline serum alanine transaminase (ALT), CD4+ T lymphocyte (CD4) count, and plasma HIV-RNA (viral load) in a cohort of HIV-infected Nigerians. METHODS:A retrospective study was conducted, on eligible treatment-naive patients who presented between August 2004 and February 2007 to the University College Hospital (UCH), Ibadan, Nigeria. Demographic data and pre-treatment laboratory results (hepatitis B surface antigen (HBsAg), HCV antibodies (anti-HCV), ALT, CD4 count and viral load) were retrieved from the medical records. Fisher's exact, two sample t-tests, and the Wilcoxon rank sum tests were used to compare groups. A logistic regression model was fitted to explore characteristics associated with co-infection status. RESULTS:A total of 1779 HIV-infected patients (male: female ratio, 1:2) met inclusion criteria. HBsAg was present in 11.9%, anti-HCV in 4.8% and both markers in 1%. HBsAg was more common among males than females (15.4% vs 10.1%, respectively p = 0.001) while anti-HCV was detected in a similar proportion of males and females (5.3% versus 4.6%, respectively p = 0.559). HIV-infected patients with anti-HCV alone had a lower mean baseline CD4 count compared to those without anti-HCV or HBsAg (197 cells/mm3 vs 247 cells/mm3, respectively p = 0.008). Serum ALT was higher among patients with HBsAg compared to those without HBsAg or anti-HCV (43 International Units (IU) vs. 39 IU, respectively p = 0.015). Male gender was associated with HBV co-infection on logistic regression (OR1.786; 95% CI, 1.306-2.443; p < 0.005). CONCLUSION:More HIV-infected females than males presented for care in this cohort. We identified a relatively high prevalence of HBV and HCV co-infection in general, and a higher rate of HBV co-infection among males than females. Pre-treatment CD4 count was significantly lower among those with HCV co-infection, while ALT was slightly higher among those with HBV co-infection. Triple infection with HIV, HBV and HCV was present in a small but significant proportion of patients. These findings underscore the importance of testing for HBV and HCV in all HIV-infected persons in our setting."Item In vitro evaluation of the antiviral activity of extracts from the lichen parmelia perlata (L) Ach. Against three RNA viruses(Creative Commons Attibution, 2007) Esimone, C. O.; Ofokansi, K. C.; Adikwu, M. U.; Ibezim, E. C.; Aboniyi, D. O.; Odaibo, G. N.; Olaleye, D. O."Substances extracted from lichens have previously been reported to possess antimicrobial activities against various groups of bacteria, fungi and viruses. Due to the high abundance of Parmelia perlata in the Eastern parts of Nigeria, we decided to explore whether it possesses antiviral activity against some common animal and human viruses. METHODOLOGY:The dried and powdered lichen was extracted with acetone, water and 4% (v/v) NaOH (to yield a crude polysaccharide fraction) using standard methods. The cytotoxicity of the extracts was investigated on HEP-2, Vero and L20 cell lines. The antiviral properties were determined against yellow fever, poliomyelitis and infectious bursal disease virus of chickens using the end-point cytopathic effect assay. Phytochemical evaluations of the extracts were also carried out. RESULTS:Phytochemical tests showed the presence of flavonoids, saponins, tannins, glycosides, steroidal aglycone, carbohydrates and also the presence, in trace amounts, of some oligodynamic elements. Cytotoxicity tests revealed that while L20 was susceptible to the extracts at a concentration of 50 microg/ml, the extracts were generally toxic to the cell lines at concentrations above 500 microg/ml. The order of sensitivity of the cell lines was L20 > HEP-2 > Vero. The water and acetone extracts showed no activity against the viruses when tested at concentrations below the cytotoxic level while the crude polysaccharide fraction showed activity against yellow fever virus with an IC50 of 15 microg/ml. The time of addition of the test extracts to the infected cells did not have significant effect on cytopathic effect inhibition. CONCLUSIONS:The results showed that the crude polysaccharide fraction from Parmelia perlata possesses specific antiviral activity against yellow fever virus. It is postulated that a major mechanism of inhibition of yellow fever infection by the crude polysaccharide fraction of the lichen could be by attack on the viral envelope."Item The complexity of circulating HIV type 1strains in Oyo state, Nigeria(Mary Ann Liebert, Inc, 2007) Sankale, J.; Langevin, S.; Odaibo, G. T.; Meloni, S. T.; Ojesina, A. I.; Olaleye, D.; Kanki, P.Multiple HIV-1 subtypes and circulating recombinant forms (CRFs) are known to circulate in west Africa. We undertook a survey of HIVs in Oyo state, in southwestern Nigeria. We analysed 71 samples from Ibadan the capital city, and 33 samples form Saki, 100 miles west of Ibadan. We sequenced part of the gag gene and the envelope C2V3 region from 102 and 89 samples, respectively. In the 87 samples for which both genes were sequenced, subtypes G and CRF02_AG were found in equal proportions (32.2%each). Other samples included CRF06_cpx(8.0%), subtype A (2.3%), C(1.1%), unclassified(1.1%), or discordant sequences suggesting the presence of a large number of recombinants involving CRF02_AG and/or subtype G(20.7%) or other subtypes(2.3%). The subtype/CRF designation was concordant in two gene fragments in the majority of samples evaluated. However, we observed difference in subtype distribution between the two locations with a predominance of subtypes G in Ibadan and CRF02 in Saki. This is first in-depth analysis of HIV variability at a state level in Nigeria. Our analysis revealed a significant level of viral heterogeneity and a geographical difference in subtype distribution, and demostrated that CRF02_AG does not account for the majority of circulating strains.Item Subtypes-specific patterns in HIV type 1reverse transcriptase and protease in Oyo state, Nigeria: implications for drug resistance and Host Response(Mary Ann Liebert, Inc, 2006) Ojesina, A. I.; Sankale, J.; Odaibo, G.; Langevin, S.; Meloni, S. T.; Sarr, A. D.; Olaleye, D.; Kanki, P. J.As the use of antiretroviral therapy becomes more widespread across Africa, it is imperative to characterize baseline molecular variability and subtype-specific peculiarities of drug targets in non-subtype B HIV-1 infection. We sequenced and analyzed 35 reverse transcriptase (RT) and 43 protease (PR) sequences from 50 therapy-naive HIV-1-infected Nigerians. Phylogenetic analyses of RT revealed that the predominant viruses were CRF02_AG (57%), subtype G (26%), and CRF06_cpx (11%). Six of 35 (17%) individuals harbored primary mutations for RT inhibitors, including M41L, V118I, Y188H, P236L, and Y318F, and curiously three of the six were infected with CRF06_cpx. Therefore, CRF06_cpx drug-naive individuals had significantly more drug resistance mutations than the other subtypes (p = 0.011). By combining data on quasisynonymous codon bias with the influence of the differential genetic cost of mutations, we were able to predict some mutations, which are likely to predominate by subtype, under drug pressure. Some subtype-specific polymorphisms occurred within epitopes for HLA B7 and B35 in the RT, and HLA A2 and A*6802 in PR, at positions implicated in immune evasion. Balanced polymorphism was also observed at predicted serine-threonine phosphorylation sites in the RT of subtype G viruses. The subtype-specific codon usage and polymorphisms observed suggest the involvement of differential pathways for drug resistance and host-driven viral evolution in HIV-1 CRF02_AG, subtype G, and CRF06_cpx, compared to subtype B. Subtype-specific responses to HIV therapy may have significant consequences for efforts to provide effective therapy to the populations infected with these HIV-1 subtypesItem Reliability of testing and potential impact on HIV prevention in Nigeria(2006) Odaibo, G. N.; Donbraye, E.; Adewumi, M. O.; Bakaery, A. S.; Ibeh, M. A.; Olaleye, D. O.Several factors including variability of human immunodeficiency virus (HIV), laboratory facilities, cost and competence of personnel handling the tests are some of the important factors that affect accuracy and reliability of HIV testing in most parts of Africa. Recently investigators in Africa have observed that antibody detection assays based on antigens derived from HIV-1 subtype B show moderate to significantly lower sensitivity for detection of infection by various non-B subtypes. In this study, we evaluated the reliability of two EIA and 12 rapid HIV-1/2 test kits that are commercially available in Nigeria using the Western immunoblotting technique as reference. A panel of 100 sera from Western blot confirmed symptomatic or asymptomatic HIV-1 infected persons and 90 seronegative patients from those referred for testing in our laboratory were used for this study. Each sample was tested with two HIV-1/2 EIA, and 12 HIV-1/2 rapid test kits commercially available at one time or the other for HIV-1/2 testing in Nigeria. Overall, the sensitivity of the two EIA kits were 100% and 91.0% with specificity of 96.7% and 91.1% respectively. The sensitivity of the rapid test kits ranged from 88% to 98.0% with specificity of 92.2% to 100%. Further analysis showed significant variation in the sensitivity and specificity of the same kit based on whether an individual had asymptomatic or symptomatic infection The results of this study highlight the problem of diagnosis of HIV infections in Africa. It shows that the sensitivity of most of the rapid assays shall not be adequate for detection of early infection. The implications of possible misdiagnosis on the various intervention strategies that rely predominantly on correct HIV status of an individual are enormous. Thus, there is an urgent need for review of the current HIV testing assays or algorithms in Nigeria and other parts of Africa.