Virology
Permanent URI for this communityhttps://repository.ibadanedu.com/handle/123456789/513
Browse
43 results
Search Results
Item Traditional crop farmers in Kogi East, Nigeria elucidate elevated HIV and AIDS prevalence level during a five -year study period(Academic Journals (Academic Journals Inc., Lagos, Nigeria), 2009) Sule, W. F.; Enemuor, S. C.; Adewumi, M. O.; Attah, O. C.The United Nations reported that HIV and AIDS have negative impact upon agriculture and increasing hunger in sub-Saharan Africa. Such a situation is postulated to synonymously occur in Nigeria. This study therefore, aimed to investigate the prevalence level of HIV antibodies and AIDS among traditional crop farmers and non-farmers comprising traders, drivers, teachers and students in Kogi East. This is one of the primary agricultural areas of Kogi State, Nigeria and is therefore of great importance to perform an assessment depicting the prevalence of local HIV infection. Documented records of HIV antibody screening from the year 2002 to 2006 at the Voluntary Counselling and HIV Testing Unit of General Hospital, Ankpa, Kogi East were reviewed. Selected data was statistically analyzed with Chi2 - test using SPSS 13.0. A total of 11,077 patients from the ages of two months to 72 years were screened during the five years. Of this, 2,510 HIV positive cases (overall prevalence of 22.70%; mean = 21.86%; n= 5; standard deviation [SD] = 5.64%) and 322 mean = 12.47%; n = 5; SD = 2.23%) AIDS-related deaths were documented. The letter group included 250 (77.6%, mean = 71.91%; SD = 15.72%) farmers. A significant higher number of farmers were seropositive (_2 = 72.710; p = 0.001, df = 1, _ = 0.05) and died (_2 = 93.255; p = 0.001, df = 1, _ = 0.05) of AIDS-related illness compared to the non-farmers. The ages of people that died range from 12 to 49 years (n = 322) with a mean age of 44.1 years. Throughout the specified five years sampling duration, more non-farmers than farmers partook in HIV antibody screening. Farmers that were seropositive for HIV antibodies and died of AIDS-related illness were significantly higher in proportion than the non-farmers.Item Human immunodeficiency virus (HIV) specific antibodies among married pregnant women and female commercial sex workers attending voluntary counseling and HIV testing (VCT) centre in Abuja, Nigeria(Medical Microbiology and Parasitology Society of Nigeria (MMSN), 2009) Sule,W. F; Adewumi, M. O.; Samuel, T. C.Generally, married women and commercial sex workers (CSWs) engage in sexual activity - an important risk factor for contracting HIV. We therefore tested a hypothesis that prevalence of HIV-1/2 antibodies among married pregnant women (PW) is not different from that of female CSWs. One hundred married PW and 99 female CSWs enrolled in the study. They were consecutively selected as they visited the VCT centre for HIV antibody test. Pertinent data were obtained from each subject using questionnaire forms; venous blood sample was aseptically collected from subjects that gave verbal consent. Plasma obtained from each sample was tested using parallel testing algorithm with DETERMINE® HIV-1/2 and HIV-1/2 STAT-PAK® test was used for statistical analysis of the data. The overall prevalence of HIV-1/2 antibodies was 29.1% (n = 199). Seroprevalence of 39.4 and 19.0% were observed for the CSWs and the PW, respectively. Using various variables, comparison of HIV-1/2 serostatus of the CSWs with that of the married PW showed that the CSWs generally had significantly higher seroprevalence. CSWs who were inconsistent in the use of condom with their clients prior to sexual intercourse in the past three months before this study (P = 0.0001, OR = 11.2) and those aged _ 39 years had significantly (P =0.004, OR = 2.6) higher seroprevalence. Though both groups recorded seropositivity, inconsistency in the use of condom appeared to be the factor mostly responsible for the significantly higher seropositivity of the female CSWs.Item Reliability of testing and potential impact on HIV prevention in Nigeria(Medical and Dental Consultants Association of Nigeria (MDCAN), 2006) Odaibo, G. N; Donbraye, E.; Adewumi, M. O.; Bakarey, A. S.; Ibeh, M. A.; Olalcye, 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 El A and 12 rapid HIV-1/2 test kits that are commercially available in Nigeria using the Western immune blotting 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 Prevalence of measles neutralizing Antibody In Children under 15years In Southwestern Nigeria(Medical Microbiology and Parasitology Society of Nigeria (MMSN), 2005) Opaleye, O. O.; Adewumi, M. O.; Donbraye E,; Bakarey, A. S. .; Odaibo, G. N.; Olaleye, O. DThe immune status of children under 15 years in the Southwestern region of Nigeria against measles virus was determined using the neutralization test with a view to assessing the herd immunity to the virus in these communities. A total of 256 serum samples collected from children were tested by the beta method of neutralization. Forty (15.6%) of these samples were found to be positive at a titre of 1:256, 35 (13.7%) at 1:128, 36(14.1%) at 1:64, 37(14.5%) at 1:32, 38 (14.8%) at 1:16, 27 (10.5%) at 1:8 and 16 (6.3%) at 1:4. Twenty-seven (10.5%) of the 256 samples had no detectable antibody to the measles virus. There was no significant relationship between the antibody titre to measles virus and the gender of the children (p > 0.05). Also, there was no significant difference using Chi square analysis between the neutralizing antibody titres and the age of the children (p > 0.05). All the children whose samples were tested were vaccinated against measles as attested to by their parents. However, the vaccination does not seem to protect all the children, for some of them had no detectable neutralizing antibody while some had low neutralizing antibody titre. In Nigeria, where only a single dose of measles vaccine is given at 9month, measles may remain a serious threat to the children population with its attendant high morbidity and mortality.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 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.