Browsing by Author "Kotey, E.N."
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Item Construction Of Potent Immunogenic Epitopes Of The Haemagglutinins Of The Seasonal Influenza A Viruses(University Of Ghana, 2021-01) Kotey, E.N.Seasonal influenza viruses are renowned for recurring annual epidemics worldwide. The Influenza A subtypes H1 and H3 are the most dominant and prevalent in recent outbreaks in humans. As with other infectious diseases, vaccines are an important public health tool. However, influenza viruses continue to evolve evading pre-existing or transient vaccine-induced immunity in addition to antigenic pressures associated with antiviral drugs. For this reason, current seasonal influenza vaccines require annual review. Vaccine (immunogen) design, efficacy, and effectiveness presents a formidable seasonal influenza management issue. Passive immunotherapy has been proposed to offer tremendous protection when appropriately used in the management of influenza, either as a substitute or to complement vaccines. A well-designed immunogen that elicits a strong antibody response towards the conserved domains of the surface Haemagglutinin (HA) protein would be critical to avert virus evolution. A detailed analysis of the highly conserved regions spanning the fusion peptide, cleavage site, and the two heptad repeats for the HA gene in over 1000 and 21,000 H1 and H3 strains, respectively was therefore conducted. Chimeric haemagglutinins (cHAs) of these conserved regions were constructed by alignment with consensus sequences generated from exotic HAs (H5 and H9 for H1-based cHAs; H7 for H3-based cHA). These cHAs were successfully expressed in Drosophila S2 cell lines. Mice were then immunized with these cHAs to determine protection against lethal doses in virus challenges against H1 and H3 seasonal viruses. Serum from seroconverted mice applied in challenge experiments indicated the presence of anti-HA specific antibodies with broadly cross-reactive potential against H5 and H7 viruses for H1 and H3-based cHAs, respectively. This study offers an alternative approach whereby multi-subtype or pan-group immunogens could be utilized for the design and generation of cross-reactive antibodies of potential therapeutic value for influenza in humansItem Genomic analysis of SARS-CoV-2 reveals local viral evolution in Ghana(2021) Ngoi, J.M.; Quashie, P.K.; Morang’a, C.M.; Bonney, J.H.K.; Amuzu, D.S.Y.; Kumordjie, S.; Asante, I.A.; Bonney, E.Y.; Eshun, M.; Boatemaa, L.; Magnusen, V.; Kotey, E.N.; Ndam, N.T.; Tei-Maya, F.; Arjarquah, A.K.; Obodai, E.; Otchere, I.D.; Bediako, Y.; Mutungi, J.K.; Amenga-Etego, L.N.; Odoom, J.K.; Anang, A.K.; Kyei, G.B.; Adu, B.; Ampofo, W.K.; Awandare, G.A.The confirmed case fatality rate for the coronavirus disease 2019 (COVID-19) in Ghana has dropped from a peak of 2% in March to be consistently below 1% since May 2020. Globally, case fatality rates have been linked to the strains/clades of circulating severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) within a specific country. Here we present 46 whole genomes of SARS-CoV-2 circulating in Ghana, from two separate sequencing batches: 15 isolates from the early epidemic (March 12–April 1 2020) and 31 from later time-points ( 25–27 May 2020). Sequencing was carried out on an Illumina MiSeq system following an amplicon-based enrichment for SARS-CoV-2 cDNA. After genome assembly and quality control processes, phylogenetic analysis showed that the first batch of 15 genomes clustered into five clades: 19A, 19B, 20A, 20B, and 20C, whereas the second batch of 31 genomes clustered to only three clades 19B, 20A, and 20B. The imported cases (6/46) mapped to circulating viruses in their countries of origin, namely, India, Hungary, Norway, the United Kingdom, and the United States of America. All genomes mapped to the original Wuhan strain with high similarity (99.5–99.8%). All imported strains mapped to the European superclade A, whereas 5/9 locally infected indi viduals harbored the B4 clade, from the East Asian superclade B. Ghana appears to have 19B and 20B as the two largest circulating clades based on our sequence analyses. In line with global reports, the D614G linked viruses seem to be predominating. Comparison of Ghanaian SARS-CoV-2 genomes with global genomes indicates that Ghanaian strains have not diverged significantly from circulating strains commonly imported into Africa. The low level of diversity in our genomes may indicate lower levels of transmission, even for D614G viruses, which is consistent with the relatively low levels of infection reported in Ghana.Item Occurrence of influenza and bacterial infections in cancer patients receiving radiotherapy in Ghana(Public Library of Science, 2022-07) Arjarquah, A.K.; Obodai, E.; Anie, H.A.; Osei, M.A.; Odoom, J.K.; Bonney, J.H.K.; Behene, E.; Kotey, E.N.; Aboagye, J.; Nyarko, S.O.; Bentum, J.; Yeboah, C.Background Influenza co-infection with bacteria is a leading cause of influenza-related deaths and severe respiratory infections, especially among high-risk groups like cancer patients undergoing treatment. However, acute respiratory infection (ARI)-like symptoms developed by uppertorso cancer (UTC) patients receiving radiotherapy are considered as side-effects of the radiation. Hence influenza and bacterial pathogens implicated in ARI are not investigated. Methods: This prospective cohort study examined 85 in-patients with upper-torso cancers undergoing radiotherapy at the National Radiotherapy, Oncology and Nuclear Medicine Centre (NRONMC) of Korle-Bu Teaching Hospital (KBTH) in Accra, Ghana. Eligible patients who consented were recruited into the study from September 2018 to April 2019. Influenza viruses A and B in addition to the following bacteria species Streptococcus pneumonia, Haemophilus influenzae, Neisseria meningitidis and Staphylococcus aureus were detected from oropharyngeal and nasopharyngeal swab specimens collected at three different time points. Presence of respiratory pathogens were investigated by influenza virus isolation in cell culture, bacterial culture, polymerase chain reaction (PCR) and next generation sequencing (NGS) assays. Results: Of the 85 eligible participants enrolled into the study, 87% were females. Participants were 17 to 77 years old, with a median age of 49 years. Most of the participants (88%) enrolled had at least one pathogen present. The most prevalent pathogen was N. meningitidis (63.4%), followed by H. influenzae (48.8%), Influenza viruses A and B (32.9%), S. pneumoniae (32.9%) and S. aureus (12.2%). Approximately, 65% of these participants developed ARI-like symptoms. Participants with previous episodes of ARI, did not live alone, HNC and total radiation less than 50 Gy were significantly associated with ARI. All treatment forms were also significantly associated with ARI. Conclusion: Data generated from the study suggests that ARI-like symptoms observed among UTC patients receiving radiotherapy in Ghana, could be due to influenza and bacterial single and co-infections in addition to risk factors and not solely the side-effects of radiation as perceived. These findings will be prime importance for diagnosis, prevention, treatment and control for cancer patients who present with such episodes during treatment.Item Phylogenetic and genetic characterization of influenza A H9N2 viruses isolated from backyard poultry in selected farms in Ghana(Wiley, 2022) Kotey, E.N.; Asante, I.A.; Adusei-Poku, M.; Arjarquah, A.; Ampadu, R.; Rodgers, D.; Nyarko, E.O.; Asiedu, W.; Dafeamekpor, C.; Wiley, M.R.; Mawuli, G.; Obeng, R.A.; Nyarko, S.O.; Magnusen, V.; Kodua, E.; Attram, N.; Nimo-Paintsil, S.C.; Pratt, C.; Fox, A.T.; Letizia, A.; Ampofo, W.K.Introduction: Avian influenza viruses (AIV) cause significant economic losses to poul- try farmers worldwide. These viruses have the ability to spread rapidly, infect entire poultry flocks, and can pose a threat to human health. The National Influenza Centre (NIC) at the Noguchi Memorial Institute for Medical Research in collaboration with the Ghana Armed forces (GAF) and the U.S. Naval Medical Research Unit No. 3, Ghana Detachment (NAMRU-3) performs biannual surveillance for influenza viruses among poultry at military barracks throughout Ghana. This study presents poultry surveil- lance data from the years 2017 to 2019. Methodology: Tracheal and cloacal swabs from sick and healthy poultry were col- lected from the backyards of GAF personnel living quarters and transported at 4◦C to the NIC. Viral ribonucleic acid (RNA) was isolated and analyzed for the presence of influenza viruses using real-time polymerase chain reaction (PCR) assays. Viral nucleic acids extracted from influenza A-positive specimens were sequenced using universal influenza A-specific primers. Results: Influenza A H9N2 virus was detected in 11 avian species out of 2000 samples tested. Phylogenetic analysis of viral haemagglutinin (HA) protein confirms the possibility of importation of viruses from North Africa and Burkina Faso. Although the detected viruses possess molecular markers of virulence and mammalian host adapta- tion, the HA cleavage site anlaysis confirmed low pathogenicity of the viruses.