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Biology subjects

Olayinka, O. T.

Publications and source records attributed to Olayinka, O. T..

3 recordsLinked to original sources

Metagenomic detection and genetic characterization of human sapovirus among children in Nigeria

Using a metagenomic sequencing approach on stool samples from children with Acute Flaccid Paralysis (AFP), we describe the genetic diversity of Sapoviruses (SaVs) in children in Nigeria. We identified six near-complete genome sequences and two partial genome sequences. Multiple SaV genogroups and genotypes were detected, including GII (GII.4 and GII.8), GIV (GIV.1) and GI (GI.2 and GI.7). Sequence identity and phylogenetic analysis showed that the Nigerian SaVs were related to previously documented gastroenteritis outbreaks associated strains from China and Japan. Minor variations in the functional motifs of the nonstructural proteins NS3 and NS5 were confirmed in the Nigerian strains. To adequately understand the effect of such amino acid changes, a better understanding of the biological function of these proteins is vital. The identification of distinct SaVs reinforces the need for robust surveillance in acute gastroenteritis (AGE) and non-AGE cohorts to better understand SaVs genotype diversity, evolution, and its role in disease burden in Nigeria.

molecular biology↗

Isolation and Identification of Enterovirus D111 in a Child with Acute Flaccid Paralysis in Nigeria.

The WHO recommended cell-culture-based algorithm requires enterovirus (EV) isolates to produce reproducible cytopathic effect (R-CPE) in RD and/or L20b cell lines. Samples with non-reproducible CPE (NR-CPE) are considered negative for EVs. We investigated whether there could be EVs lurking in samples with NR-CPE.\n\nFifty-nine (59) cell culture supernatants (CCS) (collected between 2016 and 2017) recovered from RD and L20b cell culture tubes with NR-CPE, were analyzed in this study. The tubes had been previously inoculated with stool suspension from children (<15 years) in Nigeria with acute flaccid paralysis (AFP). All CCS were screened for Enteric Adenoviruses and group A Rotavirus using a rapid immunochromatographic test kit. Subsequently, they were passaged in HEp-2 cell line. All isolates were subjected to RNA extraction, cDNA synthesis, three (5l-UTR, VP1 and EV Species C [EV-C]) different PCR assays and sequencing of amplicons. EVs were further subjected to Illumina sequencing.\n\nAll CCS were negative for Adenoviruses and group A Rotaviruses. Four CCS produced R-CPE in HEp-2 cell line, three of which were positive for the 5l-UTR assay. Of the 3 isolates two and none were positive for the VP1 and EV-C assays, respectively. One of the two VP1 amplicons was successfully sequenced and identified as Echovirus 1(E1). Illumina sequencing of the three 5l- UTR positive isolates confirmed the E1 isolate and typed the remaining two as EV-Ds (94 and 111).\n\nWe describe the first EV-D94 and 111 isolates of Nigerian origin. We also show that NR-CPE could sometimes be caused by EVs that do not produce R-CPE in RD and L20b cell lines but do so in other cell lines like HEp-2.

microbiology↗