Virology

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A possible risk of environmental exposure to HEV in Ibadan, Oyo State, Nigeria
(Taylor & Francis, 2020-08-13) Olayinka, A.; Ifeorah, I. M.; Omotosho, O.; Faleye, T. O. C.; Odukaye, O.; Bolaji, O.; Ibitoye, I.; Ope-Ewe, O.; Adewumi, M. O.; Adeniji, J. A.
"Hepatitis E virus (HEV) infection is both a major public health concern and emerging global health concern, with a documented incidence of 20 million, 3.4 million clinical cases, 70,000 deaths, and 3,000 stillbirths. The aetiologic agent, HEV is a primarily enterally transmitted hepatotropic virus. Fecal samples were collected from three selected pig farms across Ibadan, South-west Nigeria. Randomly picked samples were pooled per unit pen and fecal suspensions prepared were subjected to HEV Antigen (Ag) enzyme-linked immunosorbent assay. Molecular probing was done by Reverse Transcription and nested polymerase reaction (RT-nPCR) and deep sequencing. Sequencing was done paired-end for 300 cycles using the HiSeq system. Overall farm prevalence of 66.7% (2/3) and prevalence at individual level of 13.2% (9/68) were recorded. All nine samples positive for the ELISA screen were negative when subjected to RT-nPCR assays. Further, on deep sequencing, no HEV genomic fragment was found in the sample using de-novo assembly. Findings suggest possibly inapparent HEV in the pigs studied or a yet to be identified protein with HEV-Ag cross-reactivity ability on ELISA, thus constituting a possible risk of exposure to HEV infection in the population. Consequently, we recommend prompt intervention to unravel the mystery and break the chain of transmission.
Abundance of enterovirus C in RD-L20B cell culture-negative stool samples from acute flaccid paralysis cases in Nigeria is geographically defined
(Microbiology Society, 2018) Donbraye, E.; Olasunkanmi, O. I.; Opabode, B. A.; Ishola, T. R.; Faleye, T. O. C; Adewumi, O. M.; Adeniji, J. A.
Purpose. We recently showed that enteroviruses (EVs) andenterovirus species C (EV-C) in particular were abundant in faecal samples from children who had been diagnosed with acute flaccid paralysis (AFP) in Nigeria but declared to be EV-free by the RD-L20B cell culture-based algorithm. In this study, we investigated whether this observed preponderance of EVs (and EV-Cs) in such samples varies by geographical region. Methodology. One hundred and eight samples (i.e. 54 paired stool suspensions from 54 AFP cases) that had previously been confirmed to be negative for EVs by the WHO recommended RD-L20B cell culture-based algorithm were analysed. The 108 samples were made into 54 pools (27 each from North-West and South-South Nigeria). All were subjected to RNA extraction, cDNA synthesis and the WHO-recommended semi-nested PCR assay and its modifications. All of the amplicons were sequenced, and the enteroviruses identified, using the enterovirus genotyping tool and phylogenetic analysis. Results. EVs were detected in 16 (29.63 %) of the 54 samples that were screened and successfully identified in 14 (25.93 %). Of these, 10 were from North-West and 4 were from South-South Nigeria. One (7.14 %), 2 (14.29 %) and 11 (78.57 %) of thestrains detected were EV-A, EV-B and EV-C, respectively. The 10 strains from North-West Nigeria included 7 EV types, namely CV-A10, E29, CV-A13, CV-A17, CV-A19, CV-A24 and EV-C99. The four EV types recovered from South-South Nigeria were E31, CV-A1, EV-C99 and EV-C116. Conclusion. The results of this study showed that the presence of EVs and consequently EV-Cs in AFP samples declared to be EV-free by the RD-L20B cell culture-based algorithm varies by geographical region in Nigeria.
Acute Hepatitis E Virus Infection in Two Geographical Regions of Nigeria
(Hindawi Publishing Corporation, 2017) Ifeorah, I. M.; Bakarey, A. S.; Faleye, T. O. C.; Adewumi, M. O.; Akere, A.; Omoruyi, C. E.; Ogunwale, A. O.; Awokunle, R. F.; Sekoni, D. E.; Adeniji, J. A.
This study was therefore designed to describe acute HEV infection among antenatal clinic attendees and community dwellers from two geographical regions in Nigeria. Seven hundred and fifty plasma samples were tested for HEV IgM by Enzyme Linked Immunosorbent Assay (ELISA) technique. The tested samples were randomly selected from a pool of 1,115 blood specimens previously collected for viral hepatitis studies among selected populations (pregnant women, 272; Oyo community dwellers, 438; Anambra community dwellers, 405) between September 2012 and August 2013. One (0.4%) pregnant woman in her 3rd trimester had detectable HEV IgM, while community dwellers fromthe two study locations had zero prevalence rates of HEV IgM.Detection of HEV IgM in a pregnant woman, especially in her 3rd trimester, is of clinical and epidemiological significance.The need therefore exists for establishment of a robust HEV surveillance system in Nigeria and especially amidst the pregnant population in a bid to improve maternal and child health.
An exegesis of bacteriophage therapy: An emerging player in the fight against anti-microbial resistance
(AIMS Press, 2020) Adesanya, O.; Oduselu, T.; Akin-Ajani, O.; Adewumi, O. M.; Ademowo, O. G.
Bacteriophages (simply referred to as Phages) are a class of viruses with the ability to infect and kill prokaryotic cells (bacteria), but are unable to infect mammalian cells. This unique ability to achieve specific infectiousness by bacteriophages has been harnessed in antibacterial treatments dating back almost a decade before the antibiotic era began. Bacteriophages were used as therapeutic agents in treatment of dysentery caused by Shigella dysenteriae as far back as 1919 and in the experimental treatment of a wide variety of other bacterial infections caused by Vibrio cholerae, Staphylococcus sp., Pseudomonas sp. etc, with varying degrees of success. Phage therapy and its many prospects soon fell out of favour in western medicine after the Second World War, with the discovery of penicillin. The Soviet Union and other countries in Eastern Europe however mastered the craft of bacteriophage isolation, purification and cocktail preparation, with phage-based therapeutics becoming widely available over-the-counter. With the recent rise in cases of multi-drug resistant bacterial infections, the clamour for a return to phage therapy, as a potential solution to the anti-microbial resistance (AMR) crisis has grown louder. This review provides an extensive exposé on phage therapy, addressing its historical use, evidences of its safety and efficacy, its pros and cons when compared with antibiotics, cases of compassionate use for treating life-threatening antibiotic-resistant infections, the limitations to its acceptance and how these may be circumvented.
Antibodies to lassa virus Z protein and nucleoprtein co-occur in human sera from lassa fever endemic regions
(Medical Microbiology and Immunology, 2001) Gunther, S.; Kuhle, O.; Rehder, D.; Odaibo, G. N.; Olaleye, D. O.; Emmerich, P.; Meulen, J.; Schmitz, H.
It is not known whether the small 11-kDa Z protein of lassa virus is immunogenic during human lassa virus infection. To obtain evidence for the existence of an antibody response and to test the suitability of these antibodies for serosurveys, sera from lassa fever endemic regions(Guinea and Nigeria, n=75) were tested for co-reactivity to Z protein and nuclcoprotein (NP). Sera from a non-epidemic region (Uganda, n=50) served as a specificty control. Z protien and NP were expressed in Escherichia coli, affinity-purified, and used as antigen in western blot. Indiredt immunofluorescence (IIF) with lassa virus-infested cells was performed for comparison. Due to high unspecific reactivity of the African sera, western blot testing was performed with a 1:1,000 serum dilution. Under these conditions, none of the control sera but 12% of the sera from endemic regions co-reacted with both Z protein and NP. REactivity to Z protien was significantly associated with NP reactivity (p<10-6). Np and Z protein- specific antibodies were co-detected in 33% of the IIF-positive sera and in 5% of the IIF-negative sera (P=0.001). These data provides evidence for apperance of antibodies to Z protien and NP following Lassa virus infection. A recombination blot for detection of both antibody specificities seems to be specific but less sensitive than IIF.
Baseline CD4 T cell level predicts recovery rate after initiation of art In HIV Infected Nigerians
(Taylor & Francis Group, 2016) Adewumi, O. M.; Odaibo, G. N.; Olaleye, O. D.
The most characteristic immunologic disorder in HIV infection is the progressive loss of CD4 Tlymphocytes, thus, it remains the most important and commonly used marker for monitoring ofimmune status of HIV-infected individuals. This study monitored CD4 T lymphocyte cell dynamics among HIV patients on ART, and consequently defined an optimal baseline level required for enhanced ARV treatment. Ninety-eight (M = 33; F = 65) out of 106 consenting HIV-infected ARV-naïve patients enrolled and monitored for 24 months were considered in the analysis. The patients were classified into four groups based on baseline CD4 T lymphocyte cell levels, and specific parameters were evaluated at interval. Median CD4 T lymphocyte increased from 114 (Range: 6–330) at baseline to highest 357 (Range: 15–1036) cells/μL at 18 months of therapy. Fifty (51.0%), 58(59.2%), 75(76.5%), 69(70.4%), 63(64.3%), and 69(70.4%) doubled their preceding CD4 levels during the 3rd, 6th, 9th, 12th, 18th, and 24th months of ART, respectively. Maximum 337, 302, 360, and 475 cells/μL of blood were attained by groups commenced on ART with baseline CD4 ≤ 50, 51–100, 101–200, and 201–350 cells/μL of blood, respectively. The results show that higher baseline CD4 T lymphocyte cell level correlates with enhanced restoration,and plateau after commencement of ART.
Characterization of hepatitis delta virus strains spreading in Abuja, Nigeria
(Wiley Periodicals, Inc.,, 2019) Ifeorah, I. M.; Faleye, T. O. C.; Bakarey, A. S.; Adewumi, O. M.; Gerber, A.; Le Gal, F.; Adeniji, J. A; Gordien, E.; Onyemelukwe, N. F.
Hepatitis delta virus (HDV) is responsible for the most severe form of liver disease in humans. So far, eight genotypes (HDV‐1 to ‐8) have been individualized worldwide. Little is known about HDV strains that spread in Nigeria. HDV genotyping was performed in 15 anti–HDV positive samples from a cohort of 306 hepatitis B virus (HBV)‐infected patients in Abuja (Nigeria). Phylogenetic analyses revealed 90% were HDV‐1, two among them clustering with European/Asian HDV‐1, the remaining one being HDV‐6. It was also found that two members of a couple superinfected with the same HDV strain, were enveloped by two different HBV strains of genotype E.
Circulation of hepatitis B virus genotype-E among outpatients in tertiary hospitals in the Niger-Delta region of Nigeria
(African Journals Online (AJOL), 2022) Umego, C. F.; Mboto, C. I.; Asitok, A. D.; Osaji, L. C.; George, U. E.; Edet, U. O.; Mbim, E. N.; Faleye, T. O. C.; Adewumi, O. M.; Adeniji, J. A.
Introduction: Hepatitis B virus (HBV) infection continues to be a significant public health challenge globally, with higher disease burden in developing countries. HBV genotypes are associated with different geographical regions and clinical outcomes. Limited information exists on epidemiology of HBV in the Niger-Delta region (South-South) of Nigeria. Consequently, this study was designed to characterise hepatitis B virus infection among outpatients in selected tertiary hospitals in the region. Methodology: Between June and August 2017, consenting nine hundred asymptomatic out-patients were enrolled and initially screened for HBV infection using one step Hepatitis B surface antigen (HBsAg) strip and subsequently re-tested using HBsAg and Hepatitis B core total antibody (anti-HBc) specific Enzyme-Linked Immunosorbent Assay (ELISA). Blood serum with detectable HBsAg were subsequently subjected to DNA extraction, S-gene amplification using a nested polymerase chain reaction (PCR) protocol, gel electrophoresis, sequencing and phylogenetic analysis. Results: Seroprevalence of HBsAg was 4.6% (95% CI 2.5-7.1) and anti-HBc was 10.1% (95% confidence interval (CI) 6.1-15.3). Of the 41 HBsAg positive samples subjected to DNA extraction and HBV S-gene specific PCR, only 6 (14.6%) yielded the expected ~408bp band. Phylogenetic analysis based on HBV pre-S/S sequences identified all six typable samples as genotype E, subtype ayw4 of the West African clade. Conclusion: Results of the study confirm the presence and circulation of HBV genotype-E in the Niger-Delta region of Nigeria, thus corroborating the inclusion of the country in the Genotype E crescent. The authors advocate value-added HBV intervention in the region and the country at large.
Clinical and immunological profile of pediatric HIV infection in Ibadan, Nigeria
(SAGE, 2011) Brown, B. J.; Oladokun, R. E.; Odaibo, G. N.; Olaleye, D. O.; Osinusi, K.; Kanki, P.
In spite of the increasing number of children living with HIV in Nigeria, published data on their clinical profile are few. We describe the clinical profile at presentation of HIV-infected children at the University College Hospital, Ibadan, in a prospective study. Among 272 children studied (149 [54.8%] males; mean age 4.2 years [range 2 months to 15 years]), infection was acquired through vertical transmission in 252 (92.6%), blood transfusion in 5 (1.80%), and undetermined routes in 15 (5.5%) cases. Clinical features included weight loss (62.5%), prolonged fever (55.4%), generalized lymphadenopathy (48.6%), chronic cough (45.4%), and persistent diarrhea (28.3%). Tuberculosis was present in 45.3%, World Health Organization (WHO) clinical stages 3 and 4 disease in 70.6% and severe immunosuppression in 44.5% of cases. Pediatric HIV in Ibadan is acquired mainly vertically and most cases present with severe disease. Improved access to prevention services and early diagnosis are recommended.
Comparatives study of stool antigen test and serology for helicobacter pylori among Nigerian dyspeptic patients-a pilot study
(2010) Aje, A. O.; Otegbaye, J. A.; Odaibo, G. N.; Bojuwoye, B. J.
"OBJECTIVE:The purpose of this study was to compare the stool antigen (SAT) and immunoglobulin G (IgG) serology tests for Helicobacter pylori in dyspeptic patients in Nigeria, and determine their usefulness. METHOD:Forty six patients with dyspepsia and age and sex-matched healthy controls had their blood and stool collected and screened for H. pylori infection using the enzyme linked immunosorbent assay (ELISA) IgG serology and SAT respectively. Prevalence of H. pylori was 67.4% and 78.3%, among dyspeptics and controls respectively ((p = 0.48) with the SAT while the corresponding values for IgG serology were 67.4% and 91.3%, p = 0.005). RESULT:Patients aged > or = 50 years(8) were more positive to SAT (80%), compared with controls (13) which recorded more positivity in the age range 30-39 years (92.9%). The male gender had more positive SAT in patients (n = 15, 75%) but the SAT was more positive among the female controls 22 (84.6%). Controls in the age range < 30 years were more positive to H. pylori IgG while the patients were more positive at = 30 yrs 10 (100%). CONCLUSION:It is concluded that SAT and IgG serology for H. pylori are both useful in diagnosis of the infection, and are fairly comparable in their ability to detect infection, even in area of high endemicity."
Comparison of Algorithms for the Detection of Enteroviruses in Stool Specimens from Children Diagnosed with Acute Flaccid Paralysis
(Hindawi Publishing Corporation, 2017) Adeniji, J. A.; Ayeni, F. A.; Ibrahim, A.; Tijani, K. A.; Faleye, T. O. C.; Adewumi, M. O.
This study was designed to compare both the cell culture dependent and independent enterovirus detection algorithms recommended by the WHO and assess how either might impact our perception of the diversity of enterovirus types present in a sample. Sixteen paired samples (16 isolates from RD cell culture and their corresponding stool suspension, i.e., 32 samples) from AFP cases in Nigeria were analyzed in this study. All the samples were subjected to RNA extraction, cDNA synthesis, the WHO recommended RT-snPCR, and its modification. Amplicons were sequenced and strains identified. Enterovirus diversity was the same between the isolates and fecal suspension for the control and five of the samples. It was, however, different for the remaining 10 (62.5%) samples. Nine (CV-B4, E6, E7, E13, E14, E19, E29, EV-B75, and EV-B77) and five (CV-A1, CV-A11, CV-A13, EV-C99, and PV2) EV-B and EV-C types, respectively, were detected. Particularly, E19 and EV-B75 were only recovered from the isolates while E14, EV B77, CV-A11, and CV-A13 were only recovered from fecal suspension. Both the cell culture dependent and independent protocols bias our perception of the diversity of enterovirus types present in a sample. Hence, effort should be directed at harmonizing both for increased sensitivity.
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.
Correlation of cag-A serological status with histological parameters of chronic gastritis among dyspeptic patients in south western Nigeria
(2012) Oluwasola, A. O.; Otegbayo, J. A.; Ola, S.O.; Ebili, H. O.; Afplabi, A. O.; Odaibo, G. N.
"BACKGROUND:The aim of this study was to determine the sero-prevalence of Cag-A strains of Helicobacter pylori in both dyspeptic and non-dyspeptic individuals and also correlate the serological status of Gag-A strain of H. pylori with the various graded histological variables of chronic gastritis in the dyspeptic patients. METHODS:Using helicobacter p120 Cag-A enzyme linked immunosorbent assay, Cag-A serology test was carried out on 65 dyspeptic patients and 65 age and sex matched non-dyspeptic controls. The gastric biopsies of the patients were also histologically examined to ascertain the presence, nature and degree of the following histological variables of gastritis: colonisation by H. pylori; inflammation, intestinal metaplasia and mucosal atrophy. The CagA serological status was then correlated with the graded variables. RESULTS:A prevalence of 46.2% and 58.8% seropositivity for Cag-A strain of H. pylori was found among dyspeptic patients and control individuals respectively. Cag-A seropositive patients accounted for nine(81.8%) of the 11 cases with moderate to severe activity and 75% of both cases with mucosal atrophy and cases with intestinal metaplasia. CONCLUSION:Infection with Cag-A positive Helicobacter pylori was equally prevalent among both dyspeptic patients and control subjects studied. CagA seropositivity, however, appeared to be associated with higher inflammatory activity in the mucosa of patients with chronic gastritis and may be associated with intestinal metaplasia and mucosal atrophy in H. pylori-induced chronic gastritis."
"Defining the Enterovirus Diversity Landscape of a Fecal Sample: A Methodological Challenge?"
(MDPI, 2015) Faleye, T. O. C.; Adewumi, M. O.; Adeniji, J. A.
Enteroviruses are a group of over 250 naked icosahedral virus serotypes that have been associated with clinical conditions that range from intrauterine enterovirus transmission withfataloutcome through encephalitis and meningitis, to paralysis. Classically, enterovirus detection was done by assaying for the development of the classic enterovirus-specific cytopathic effect in cell culture. Subsequently, the isolates were historically identified by a neutralization assay.More recently, identification has been done by reverse transcriptase-polymerase chain reaction (RT-PCR). However, in recent times, there is a move towards direct detection and identification of enteroviruses from clinical samples using the cell culture-independent RT semi-nested PCR (RT-snPCR) assay. This RT-snPCR procedure amplifies the VP1 gene, which is then sequenced and used for identification. However, while cell culture-based strategies tend to show a preponderance of certain enterovirus species depending on the cell lines included in the isolation protocol, the RT-snPCR strategies tilt in a different direction. Consequently, it is becoming apparent that the diversity observed in certain enterovirus species, e.g., enterovirus species B(EV-B), might not be because they are the most evolutionarily successful. Rather, it might stem from cell line-specific bias accumulated over several years of use of the cell culture-dependent isolation protocols. Furthermore, it might also be a reflection of the impact of the relative genome concentration on the result of pan-enterovirus VP1 RT-snPCR screens used during the identification of cell culture isolates. This review highlights the impact of these two processes on the current diversity landscape of enteroviruses and the need to re-assess enterovirus detection and identification algorithms in a bid to better balance our understanding of the enterovirus diversity landscape.
Demographic and laboratory evidence of non sexual transmission of HIV in Nigeria
(MEDIMOND, 2004) Odaibo, G. N.; Bamgbose, G.; Jegede, A. S.; Sankale, J. L.; Omotade, O. O.; Olaleye, D. O.; Kanki, P.
Apart from heterosexual transmission, not much is known about the contribution of the other modes of spread of HIV in Africa. To evaluate the importance of non-sexual/non-vertical transmission in adults and children in Nigeria, data from mother-child pairs (community and hospital) and a community HIV surveillance among adult populations in two communities of Oyo State in SW Nigeria were analysed. In the community-based mother-child pair HIV testing, 18 of 476 (3.8%) under 5 years children were positive for HIV antibodies with only one positive mother-child pair. In the hospital surveillance (1996-1997) 10(7.0%) children of 132 mother-child pairs were positive while three (30%) of the 10 mothers were HIV negative. Similarly, 5(10%) of the mothers of 10 H1V positive children (2004) were HIV negative. In another community study, 5(13.2%) of the 38 adults from Ibadan and 12(4.8%) of 251 from Saki who claimed they never had sexual experience were HIV positive. Use of contaminated instruments and blood transfusion remain important routes of transmission of HIV in Nigeria.
Demographic factors in HIV infected patients seen at UCH, Ibadan, Nigeria.
(2005) Ola, S. O.; Ladipo, M. M. A.; Otegbayo, J. A.; Odaibo, G. N.; Bamgboye, E. A.; Nwaorgu, O. G. B.; Shokunbi, W.; Olaleye, O. D.
"There is a rising rate of Human Immunodeficiency Virus (HIV) infection in Nigeria. Good knowledge of the demographic characteristics of the patients with HIV/AIDS may be of great importance in understanding its epidemiology in Nigeria and could facilitate efforts at curtailing the spread of the infection. The study was planned to determine the demographic factors in Nigerian patients with HIV infection. The study was conducted at the University College Hospital (U.C.H), Ibadan, located in the South West of Nigeria. It was a retrospective study of patients with HIV infection attending the U.C.H. from 1988 to 2002. The data collected from the clinical records of the patients with HIV infection included age, sex, marital status, number of spouses, tribe, occupation, education and their religious affiliation. A total of 460 patients aged 1-76 years with peak at 30-34 years were studied. The male/female ratio was 1.06 and the males were the older group. Traders accounted for 40% with female preponderance while the artisans (19.9%) and the military (2.9%) were mostly males. The patients were of Yoruba (70.6%), Igbo (20.0%) and Hausa (9.1%) races. Among the patients with marital status, majority (71.4%) were married while those separated and widowed accounted for 3.5% and 2.6% respectively. Also, a higher proportion of the female HIV patients were Christians whereas the majority of the males were of Islamic religion. Although, there was a low frequency of records on education, the males had better formal education. In conclusion, the study shows that HIV infection is presently an adult disease affecting the most productive segment of the Nigerian population regardless of the individual occupation, educational status, tribe and religious affiliation. Also, it shows that the infection could be associated with heterosexual intercourse."
Detection and circulation of hepatitis B virus immune escape mutants among asymptomatic community dwellers in Ibadan, southwestern Nigeria
(Elsevier, 2015) Faleye, T. O. C.; Adewumi, O. M.; Ifeorah, I. M.; Akere, A.; Bakarey, S. A.; Omoruyi, E.C.; Oketunde, K.; Awonusi, O. B.; Ajayi, M. R.; Adeniji, J. A.
In 2012, the first Nigerian Hepatitis B Virus (HBV) immune escape mutant (IEM) case was detected in a pregnant woman in southwestern Nigeria. Consequently, this study was designed to investigate the presence and possible circulation of IEMs amongst asymptomatic community dwellers in southwestern Nigeria. Methods: Blood specimens collected from 438 asymptomatic community dwellers were screened for HBsAg using ELISA technique. Subsequently, the S-gene was amplified in HBsAg positive samples by a nested PCR protocol, and amplicons sequenced. Isolates were then subtyped by amino acid residues at positions 122, 127, 134 and 160, and genotyped by phylogenetic analysis. Results of the 31 (7.08%) samples positive for HBsAg, the _408 bp Sgene fragment was successfully amplified and sequenced in 27. Samples obtained from 4 patients could not be amplified due to low titres. Sequence data from only 15 of the isolates could be analysed further as eight of the remaining 12 had multiple peaks while the rest three showed no similarity to any HBV gene when subjected to BLAST analysis. Thirteen of the 15 isolates were identified as genotype E. Eleven of which were subtyped as ayw4 while the remaining two could not be subtyped due to sR122Q/P substitutions. The last two isolates that could not be genotyped and subtyped had other mutations in the ‘‘a’’ determinant associated with IEMs. Conclusions: This study confirmed presence and circulation of HBV IEM in Nigeria, the country’s inclusion in the genotype E crescent, and the value of phylogenetic analysis in HBV identification.
Detection of hepatitis B virus isolates with mutations associated with immune escape mutants among pregnant women in Ibadan, southwestern Nigeria
(Springer, 2015) Faleye, T .O. C.; Adewumi, M. O.; Ifeorah, I. M.; Omoruyi, E. C.; Bakarey, S. A.; Akere, A.; Awokunle, F.; Ajibola, H. O.; Makanjuola, D. O.; Adeniji, J. A.
Perinatal transmission of hepatitis B virus (HBV) and its associated immune escape mutants (IEMs), is the major vehicle through which a population of chronically infected people who serve as infectious HBV reservoirs is maintained in communities. Therefore, to assess the risk of perinatal transmission, 272 pregnant women attending ante-natal clinics in Ibadan metropolis, southwestern, Nigeria, were screened for HBsAg using ELISA technique. Samples positive for HBsAg were subjected to HBV DNA detection by PCR amplification of the S-gene and amplicon sequencing. Isolates were genotyped and subtyped using a combination of molecular techniques. Fifteen (5.5%) of the pregnant women were positive for HBsAg of which HBV DNA was detected in seven. Five of the isolates were typed as genotype E subtype ayw4 using amino acid residues at positions 122, 127, 134 and 160. Another could only be typed as genotype E subtype ayw4 by further phylogenetic analysis. The remaining one isolate did not belong to any of genotypes A – H. Three of the HBV isolates including the untypable, had mutations in the ‘a’ determinant associated with IEMs. This study confirms the endemicity of HBV, the risk of perinatal transmission and the circulation of genotype E subtype ayw4 in Nigeria. It further demonstrates the presence of IEMs in Nigeria
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.
Detection of Non-Cytopathic Enteroviruses in Supernatant of RD and L20B Cell Cultures
(ResearchersLinks Ltd., 2020-08-29) Adewumi, M. O.; Ogunsakin, T. R.; Ogunrombi, S. B.; Ojeamiren, I.; Olawole, A. S.; Faleye, T. O. C.; Adeniji, J. A.
We investigated the likely presence of enteroviruses in supernatants of cytopathic effect (CPE) negative RD and L20B cell culture tubes in which faecal suspension from acute flaccid paralysis (AFP) cases were cultured. Samples analyzed were collected in 2017 as part of the AFP surveillance program in Nigeria and declared negative for enteroviruses because they did not produce CPE in RD and L20B cell lines. In all, 120 cell culture supernatants (60 each on RD and L20B cell lines) that emanated from 30 stool suspensions (2 samples per case) were analyzed as 60 pools (pooled per case by cell line). Pools were subjected to RNA extraction, RT-snPCR, amplicon sequencing and phylogenetic analysis. Eleven and one of the 30 pools of RD and L20B cell culture supernatants, respectively, were positive for the RT-snPCR. Nine of the 11 amplicons from RD and the only from L20B were sequenced and identified as seven EV types; Coxsackievirus A4 (CVA4), CV-A6, CV-A13, CV-A17 (both RD and L20B), CV-B2, Echovirus 9 (E9) and Enterovirus A76 (EVA76). Our findings suggest some enteroviruses are present in and might be replicating in RD cell line without producing CPE. We also report the existence of CV-A6 genotype E (possibly sub-Saharan Africa restricted).