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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 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.Item Neutralizing antibodies against poliovirus serotypes among children in southwest Nigeria(Oxford University Press, 2005) Adewumi, M. O.; Donbraye, E.; Odaibo, G. N.; Bakarey, A. S.; Opaleye, O. O.; Olaleye, D. O.In May 1988, the World Health Assembly resolved to eradicate poliomyelitis globally by the year 2000. Despite the reported success in national immunization days, acute flaccid paralysis surveillance and accelerated efforts to meet the deadline including ‘mopping-up’ were executed in 1999 and subsequent years. Nigeria remains one of the major reservoirs for wild poliovirus transmission. Neutralizing antibody titre to the three poliovirus serotypes was determined among children from different communities in southwest of Nigeria, and analysed by age, gender and location. About 0.5–2 ml of blood sample was collected by venepuncture from each child. Aliquot of serum from each blood sample was inactivated prior to neutralization test by the beta method for poliovirus antibodies. A total of 347 (59.6 per cent) out of 500 and 82 children enrolled for the study had at least antibody titre of 1:8 against each of the three poliovirus serotypes. Immunity level to the three poliovirus serotypes increased with age and peaked in children aged 4–6 years. Seven (53.8 per cent) out of 13 unvaccinated children tested in the study had detectable neutralizing antibody to the three serotypes. Immunity pattern of P2 > P1 and P3 was observed but no correlation between gender and antibody to the poliovirus serotypes. The populations had 59.6 per cent herd immunity for the three poliovirus serotypes. In a country with high incidence of poliomyelitis this situation leaves a high number of non-immunized children at the risk of infection with one or more poliovirus serotypes.Item Mother-to-child transmission of different HIV-1 subtypes among ARV NAÏVE infected pregnant women in Nigeria(2006) Odaibo, G. N.; Olaleye, D. O.; Heyndrick, L.; Vereecken, K.; Houwer, K.; Jassens, W."The rate of mother-to-child transmission (MTCT) of HIV as well as the implications of the circulating multiple subtypes to MTCT in Nigeria are not known. This study was therefore undertaken to determine the differential rates of MTCT of HIV-1 subtypes detected among infected pregnant women before ARV intervention therapy became available in Nigeria. Twenty of the HIV-positive women who signed the informed consent form during pregnancy brought their babies for follow-up testing at age 18-24 months. Plasma samples from both mother and baby were tested for HIV antibody at the Department of Virology, UCH, Ibadan, Nigeria. All positive samples (plasma and peripheral blood mononuclear cells - PBMCs) were shipped to the Institute of Tropical Medicine, Antwerp, Belgium, where the subtype of the infecting virus was determined using the HMA technique. Overall, a mother-to-child HIV transmission rate of 45% was found in this cohort. Specifically, 36.4%, 66.7% and 100% of the women infected with HIV-1 CRF02 (IbNg), G and B, respectively, transmitted the virus to their babies. As far as it can be ascertained, this is the first report on the rate of MTCT of HIV in Nigeria. The findings reported in this paper will form a useful reference for assessment of currently available therapeutic intervention of MTCT in the country."Item HIV infection among patients with pulmonary tuberculosis in Nigeria(2005) Odaibo, G. N.; Gboun, M. F.; Ekanem, E. E.; Gwarzo, S. N.; Saliu, I.; Egbewunmi, S. A.; Abebe, E. A.; Olaleye, D. O.Respiratory problems like Pneumocystic carinni and Pulmonary tuberculosis (PTB) are among the common opportunistic infections in patients with HIV/AIDS. The risk of acquiring Mycobacterium tuberculosis in a community becomes greater with increase in the number of HIV positive persons with active tuberculosis. This study was carried out to determine the magnitude of HIV infection among PTB patients in different parts of Nigeria as part of the year 2000 national HIV surveillance programme. Blood samples were collected on blotting paper from a total of 2826 individuals attending TB clinics between 1st of September and 1st November, 2000. Samples were collected from patients with confirmed PTB from 12 states in the 6 geopolitical/health zone (2 states/zone) of Nigeria as part of high risk sentinel population groups. Samples were tested for the presence of HIV antibodies using commercial ELISA (Genescreen HIV-1/2, Sanofi Pasteur, Paris). All initially reactive samples were retested with a rapid EIA (Gene II, Sanofi Pasteur, Paris) according to the WHO recommendations (option II). HIV Prevalence in the states varied from 4.2% in Oyo to 35.1% in Benue States with a median prevalence of 17.0%. HIV Prevalence increased with age to a peak of 23.9% among PTB patients 30-39 years and then declined progressively to 12.8% among those 60 years and above. A relatively high HIV infection rate (13.8%) was found among the young adolescent age group 10-19 years. There was no significant difference in the rate among male and female PTB patients tested. Comparison with results of previous HIV sero-surveys shows a steady increase in HIV prevalence among PTB patients over the years. The high prevalence of HIV among young PTB patients aged 10-19 years in this study is worrisome and must be noted for intervention.Item Respiratory syncytial virus infection: denominator-based studies in Indonesia, Mozambique, Nigeria and South Africa(2004) Robertson, S. E.; Roca, A.; Alonso, P.; Simoes, E. A. F.; Kartasasmita, C. B.; Olaleye, D. O.; Odaibo, G. N.; Collinson, M.; Venter, M.; Zhu, Y.; Wright, P. F.OBJECTIVE:To assess the burden of respiratory syncytial virus (RSV)-associated lower respiratory infections (LRI) in children in four developing countries.METHODS:A WHO protocol for prospective population-based surveillance of acute respiratory infections in children aged less than 5 years was used at sites in Indonesia, Mozambique, Nigeria and South Africa. RSV antigen was identified by enzyme-linked immunosorbent assay performed on nasopharyngeal specimens from children meeting clinical case definitions.FINDINGS:Among children aged < 5 years, the incidence of RSV-associated LRI per 1000 child-years was 34 in Indonesia and 94 in Nigeria. The incidence of RSV-associated severe LRI per 1000 child-years was 5 in Mozambique, 10 in Indonesia, and 9 in South Africa. At all study sites, the majority of RSV cases occurred in infants.CONCLUSION:These studies demonstrate that RSV contributes to a substantial but quite variable burden of LRI in children aged < 5 years in four developing countries. The possible explanations for this variation include social factors, such as family size and patterns of seeking health care; the proportion of children infected by human immunodeficiency syndrome (HIV); and differences in clinical definitions used for obtaining samples. The age distribution of cases indicates the need for an RSV vaccine that can protect children early in life.