Atypical serologic profiles of hepatitis B virus infection across clinical cohorts of patients in Southwestern Nigeria.

Hepatitis B virus (HBV) infection follows a natural course of events predicted by a dynamic interaction between viral antigen and the host immune system, which forms the basis for HBV serological diagnosis. These interactions may deviate from the typical serologic patterns. This study investigates the types of atypical HBV serologic profiles (AHBSP) across clinical cohorts of patients with HBV infection in southwestern Nigeria. This is a cross-sectional, hospital-based, multi-centered study. Patients' sera were analyzed for HBsAg, anti-HBs, HBeAg, anti-HBe, anti-HBc IgM, and anti-HBc IgG by ELISA from 279 study participants attending selected gastroenterology clinics between August 2019 and December 2020. The prevalence of atypical HBV serologic profiles was 27% (n = 76). The mean age of patients was 35.7 ± 11.2 years. The gender distribution involved 183 females (65.6%) and 96 males (34.4%). Across clinical cohorts of patients with atypical serologic profiles, HBeAg Negative, anti-HBe positive with detectable HBV DNA had the highest prevalence of 21% followed by isolated anti-HBc antibody positive, HBsAg negative and detectable HBV DNA, 5%. The atypical serologic profiles, HBeAg positive, HBsAg negative with detectable HBV DNA and concurrent anti-HBs with HBsAg, had the lowest prevalence, 0.4%, respectively. This study identified the considerable presence of atypical HBV serologic profiles across clinical cohorts of HBV infection in southwestern Nigeria.

Molecular epidemiology of hepatitis D virus circulating in Southwestern Nigeria.

BACKGROUND: Hepatitis B virus (HBV) and hepatitis D virus (HDV) infections are major public health problems in sub-Saharan Africa. Whereas it is known that HBV infection is endemic in Nigeria, there is only little data about HDV prevalence available. Here, we assessed the HDV seroprevalence and determined the HDV and HBV genotypes distribution among HBsAg positive individuals in Southwestern Nigeria. METHODS: This cross-sectional study involved 188 serum samples from HBsAg positive outpatients recruited at four tertiary hospitals in Southwestern Nigeria. Anti-HDV antibodies were detected by ELISA while HDV-RNA was detected by RT-PCR. Sequencing followed by phylogenetic analyses and HBV genotype-specific PCR were used to characterize HDV and HBV genotypes, respectively. RESULTS: Out of 188 HBsAg positive serum samples, 17 (9 %) showed detectable HDV-RNA. Anti-HDV antibodies test was possible from 103 samples and were observed in 4.9 % (5/103) patients. There was no significant difference in HDV prevalence between four main cities across the country. 64.7 % of HDV-RNA positive samples were from males and 35.3 % from females (P < 0.05). No significant associations were observed with regard to HDV seroprevalence and available demographic factors. Phylogenetic analyses demonstrated a predominance of HDV genotype 1 and HBV genotype E among the HDV-RNA/HBsAg positive patients. CONCLUSIONS: In conclusion, our study showed a high prevalence of HDV infection in HBsAg carriers and the predominance of HDV genotype 1 infection in Nigerian HBV endemic region. The findings contribute to a better understanding of the relevance of HDV/HBV co-infection and circulating genotypes.

A multi-country phase 2 study to evaluate the suitcase lab for rapid detection of SARS-CoV-2 in seven Sub-Saharan African countries: Lessons from the field.

BACKGROUND: The COVID-19 pandemic led to severe health systems collapse, as well as logistics and supply delivery shortages across sectors. Delivery of PCR related healthcare supplies continue to be hindered. There is the need for a rapid and accessible SARS-CoV-2 molecular detection method in low resource settings. OBJECTIVES: To validate a novel isothermal amplification method for rapid detection of SARS-CoV-2 across seven sub-Sharan African countries. STUDY DESIGN: In this multi-country phase 2 diagnostic study, 3,231 clinical samples in seven African sites were tested with two reverse transcription Recombinase-Aided Amplification (RT-RAA) assays (based on SARS-CoV-2 Nucleocapsid (N) gene and RNA-dependent RNA polymerase (RdRP) gene). The test was performed in a mobile suitcase laboratory within 15 min. All results were compared to a real-time RT-PCR assay. Extraction kits based on silica gel or magnetic beads were applied. RESULTS: Four sites demonstrated good to excellent agreement, while three sites showed fair to moderate results. The RdRP gene assay exhibited an overall PPV of 0.92 and a NPV of 0.88. The N gene assay exhibited an overall PPV of 0.93 and a NPV 0.88. The sensitivity of both RT-RAA assays varied depending on the sample Ct values. When comparing sensitivity between sites, values differed considerably. For high viral load samples, the RT-RAA assay sensitivity ranges were between 60.5 and 100% (RdRP assay) and 25 and 98.6 (N assay). CONCLUSION: Overall, the RdRP based RT-RAA test showed the best assay accuracy. This study highlights the challenges of implementing rapid molecular assays in field conditions. Factors that are important for successful deployment across countries include the implementation of standardized operation procedures, in-person continuous training for staff, and enhanced quality control measures.

Effect of tenofovir, an antiretroviral drug, on hepatic and renal functional indices of Wistar rats: protective role of vitamin E.

BACKGROUND: Tenofovir (TFR) is a nucleotide reverse transcriptase inhibitor with activity against human immunodeficiency virus. We studied the effect of TFR administered to Wistar rats on hepatic and renal function markers and the possible modulatory role of vitamin E (Vit E). METHODS: The study consists of four groups of six rats each. The first group served as control, the second group received TFR at 50 mg/kg/day for 4 weeks, third group received TFR and Vit E, and the last group received Vit E alone. RESULTS: TFR administration caused a significant (p<0.05) increase in the levels of serum urea, creatinine, urinary glucose, and protein by 65%, 51%, 88%, and 79%, respectively, relative to controls. This was followed by a significant (p<0.05) reduction in creatinine clearance of TFR-treated rats. There were no significant differences (p>0.05) in the activities of serum aminotransferases, γ-glutamyltransferase, and alkaline phosphatase in TRF-treated rats relative to controls. TFR administration caused a marked elevation of malondialdehyde (MDA; index of lipid peroxidation) in the animals. Specifically, serum, hepatic, and renal MDA levels increased by 75%, 90%, and 102%, respectively. TRF-treated rats had significantly (p<0.05) reduced activities of renal catalase, glutathione-S-transferase, and superoxide dismutase. Supplementation of Vit E ameliorated TFR-induced effects by decreasing the levels of MDA and enhancing the activities of renal antioxidative enzymes. The biochemical data were supported by histopathological findings from the slides. CONCLUSIONS: TFR increased oxidative stress and altered kidney function markers in the rats, whereas supplementation of Vit E attenuated these effects.

HIV-1 Central Nervous System Compartmentalization and Cytokine Interplay in Non-Subtype B HIV-1 Infections in Nigeria and Malawi.

HIV-1 compartmentalization in the central nervous system (CNS) and its contribution to neurological disease have been well documented. Previous studies were conducted among people infected with subtypes B or C where CNS compartmentalization has been observed when comparing viral sequences in the blood to virus in cerebrospinal fluid (CSF). However, little is known about CNS compartmentalization in other HIV-1 subtypes. Using a deep sequencing approach with Primer ID, we conducted a cross-sectional study among Nigerian and Malawian HIV-1 cohorts with or without fungal Cryptococcus infection diagnosed as cryptococcal meningitis (CM) to determine the extent of CSF/CNS compartmentalization with CM. Paired plasma and CSF samples from 45 participants were also analyzed for cytokine/chemokine levels. Viral populations comparing virus in the blood and the CSF ranged from compartmentalized to equilibrated, including minor or partial compartmentalization or clonal amplification of a single viral sequence. The frequency of compartmentalized viral populations in the blood and CSF was similar between the CM- and CM+ participants. We confirmed the potential to see compartmentalization with subtype C infection and have also documented CNS compartmentalization of an HIV-1 subtype G infection. Cytokine profiles indicated a proinflammatory environment, especially within the CSF/CNS. However, sCD163 was suppressed in the CSF in the presence of CM, perhaps due to elevated levels of IL-4, which were also a feature of the cytokine profile, showing a distinct cytokine profile with CM.

Identification of previously untypable RD cell line isolates and detection of EV-A71 genotype C1 in a child with AFP in Nigeria.

We previously attempted to identify 96 nonpolio enteroviruses (EVs) recovered in RD cell culture from children <15 years with acute flaccid paralysis in Nigeria. We succeeded in identifying 69 of the isolates. Here, we describe an attempt to identify the remaining 27 isolates. Twenty-six (the 27th isolate was exhausted) isolates/samples that could not be typed previously were further analyzed. All were subjected to RNA extraction, cDNA synthesis, enterovirus 5'-UTR-VP2 PCR assay and a modified VP1 snPCR assay. Both the 5'-UTR-VP2 and VP1 amplicons were sequenced, isolates identified and subjected to phylogenetic analysis.Twenty of the 26 samples analyzed were identified. Altogether, 23 (three samples had co-infection) EV strains were recovered. These belong to 11 EV (one EVA, nine EVB and one EVC) types which were EVA71 genotype C1 (1 strain), CVB3 (7 strains), CVB5 (1 strain), E5 (2 strain), E11 (3 strains), E13 (2 strain), E19 (1 strain), E20 (1 strain), E24 (2 strains), EVB75 (1 strain) and EVC99 (2 strains). Of the 11 EV types, the 5'-UTR-VP2 assay identified seven while the VP1 assay identified 10. Both assays simultaneously detected 7 of the 11 EV types identified in this study with 100% congruence. We successfully identified 20 of 26 samples that were previously untypable. We also provided evidence that suggests a clade of EVA71 genotype C1 might have been circulating in sub-Saharan Africa since 2008. Finally, we showed that the 5'-UTR -VP2 assay might be as valuable as the VP1 assay in EV identification.

Abundance of enterovirus C in RD-L20B cell culture-negative stool samples from acute flaccid paralysis cases in Nigeria is geographically defined.

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 the strains 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.

Immunity to poliovirus serotypes in children population of selected communities in South-west, Nigeria.

BACKGROUND: Poliovirus outbreaks are still reported in Nigeria despite renewed efforts to improve vaccine coverage, thus suggesting the existence of susceptible hosts. Also, there is anecdotal evidence of variation in vaccine coverage by region and specifically between urban and rural communities. Consequently, this study assessed neutralizing antibodies to poliovirus serotypes among children in selected urban and rural communities in south western Nigeria. METHODOLOGY: Two hundred and forty-four {(M=119, F=125); Urban: 142 (M=63, F=79); Rural: 102 (M=56, F=46)} children of consenting parent/guardian aged one week to 15 years were enrolled for the study. About 2-3ml of blood was collected from each child by venepuncture into a labelled sterile container free of anticoagulants. Subsequently, questionnaire was administered to the parent/guardian of each child to retrieve relevant information. Recovered sera were analysed for detectable neutralizing antibodies to poliovirus serotypes by the standard method of constant virus, varying serum dilutions. RESULTS: Overall, 64.3% (n=157) of the children had detectable neutralizing antibodies to the three poliovirus serotypes. Also, 84.8% (n=207), 91.0% (n=222) and 75.0% (n=183) of the children had detectable antibodies to poliovirus serotypes 1, 2 and 3 respectively. Eighty seven (35.7%) of the children had no detectable neutralizing antibody to at least one of the three poliovirus serotypes, while 9 (3.7%) children had no detectable neutralizing antibody to the three poliovirus serotypes. Geometric mean titre (GMT) of neutralizing antibodies to the three poliovirus serotypes varied significantly (p=0.0005). CONCLUSION: Disparity in immunity to poliovirus infection and existence of children with low or zero neutralizing antibody levels were confirmed.

Detection and circulation of hepatitis B virus immune escape mutants among asymptomatic community dwellers in Ibadan, southwestern Nigeria.

BACKGROUND: 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.