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1.
Biomed Res Int ; 2024: 9975781, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38595329

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is shed in the stool of infected individuals and can be detected in sewage and wastewater contaminated with infected stool. This study is aimed at detecting the virus and its potential survival in sewage and wastewater in Ghana. The cross-sectional study included samples from 16 validated environmental surveillance sites in 7 regions of Ghana. A total of 354 samples composed of wastewater (280) and sewage (74) were collected from November 2020 to November 2022. Overall, 17% of the samples were positive for SARS-CoV-2 by real-time PCR, with 6% in sewage and 11% in wastewater. The highest number of positive samples was collected from the Greater Accra Region (7.3%) with the least recorded in the Bono East Region (0.6%). Further characterization of the positive samples using the next-generation sequencing (NGS) approach yielded two variants: Alpha (B.1.1.7) and Delta (AY.36). Attempts to isolate SARS-CoV-2 in the Vero cell line were not successful probably due to the low viral load concentrations (Ct values > 35) or prolonged exposure to high temperatures rendering the virus noninfectious. Our findings suggest that SARS-CoV-2 RNA in sewage and wastewater may not be infectious, but the prevalence shows that the virus persists in the communities within Ghana.


Assuntos
COVID-19 , Esgotos , Humanos , Águas Residuárias , SARS-CoV-2/genética , Gana/epidemiologia , Estudos Transversais , RNA Viral/genética , COVID-19/epidemiologia
2.
Front Microbiol ; 13: 973771, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36090108

RESUMO

Expanding access to effective antiretroviral therapy (ART) is a major tool for management of Human Immunodeficiency Virus (HIV) infection. However, rising levels of HIV drug-resistance have significantly hampered the anticipated success of ART in persons living with HIV (PLWH), particularly those from Africa. Though great strides have been made in Ghana toward achieving the UNAIDS "95-95-95" target, a substantial number of PLWH receiving ART have not attained viral suppression. This study investigated patterns of drug resistance mutations in ART naïve as well as ART-experienced PLWH receiving first-line regimen drugs from Ghana. In a cross-sectional study, blood samples were collected from HIV-1 infected adults (≥18 years) attending HIV/AIDS clinic at the Eastern Regional Hospital, Koforidua, Ghana from September to October 2017. Viral RNA isolated from plasma were subjected to genotypic drug resistance testing for Protease Inhibitors (PI), Reverse Transcriptase Inhibitors (RTI), and Integrase Strand Transfer Inhibitors (INSTI). A total of 95 (84 ART experienced, 11 ART naïve) HIV-1 infected participants were sampled in this study. Sixty percent (50/84) of the ART-experienced participants were controlling viremia (viral load < 1,000 copies/ml). Of the 95 patient samples, 32, 34, and 33 were successfully sequenced for protease, reverse-transcriptase, and integrase regions, respectively. The dominant HIV-1 subtypes detected were CRF02_AG (70%), and A3 (10%). Major drug resistance associated mutations were only detected for reverse transcriptase inhibitors. The predominant drug resistance mutations were against nucleos(t)ide reverse transcriptase inhibitors (NRTI)-M184V/I and non-nucleos(t)ide reverse transcriptase inhibitors (NNRTI)-K103N. In the ART-experienced group, M184V/I and K103N were detected in 54% (15/28) and 46% (13/28) of individuals, respectively. Both mutations were each detected in 33% (2/6) of ART naïve individuals. Multiclass resistance to NRTI and NNRTI was detected in 57% of ART-experienced individuals and two ART naïve individuals. This study reports high-level resistance to NNRTI-based antiretroviral therapy in PLWH in Ghana. However, the absence of major PI and INSTI associated-mutations is a good signal that the current WHO recommendation of Dolutegravir in combination with an NRTI backbone will yield maximum benefits as first-line regimen for PLWH in Ghana.

3.
Biochem Biophys Res Commun ; 607: 124-130, 2022 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-35367824

RESUMO

CD8+ T-cell responses exert strong suppressive pressure on viral replication and select for viral escape mutations in HIV infection. Multiple viral epitopes restricted by major histocompatibility complex class I (MHC-I) are targeted by CD8+ T cells. Sequential selection of viral escape mutations in individual epitope-coding regions could result in failure in CD8+ T cell-based viral control leading to disease progression. However, how this sequential selection of epitope mutations occurs has not fully been determined. Here, we examined sequential selection of viral mutations in seven CD8+ T-cell epitope-coding regions in a macaque AIDS model of simian immunodeficiency virus mac239 (SIVmac239) infection. In seven SIVmac239-infected Burmese rhesus macaques possessing MHC-I haplotype 90-120-Ia, selection of viral mutations was observed in five to seven of the seven 90-120-Ia-associated CD8+ T-cell epitope-coding regions in a year post-infection. Of the seven CD8+ T-cell epitopes, viral mutation selection was detected first at two epitopes, Gag206-216 and Nef9-19, but was found finally at Vif114-124 epitope in most animals. Viral loads in 6 months were significantly associated with the number of mutated CD8+ T-cell epitope-coding regions 1 year post-infection. Tetramer analysis revealed early induction of Gag241-249 specific CD8+ T-cell responses, which did not always result in early selection of viral mutations in the Gag241-249 epitope, suggesting that the order of epitope mutation selection may not be determined only by immunodominance. This SIV infection model using 90-120-Ia-positive macaques would be useful for analysis of the determinants for sequential epitope mutation selection, contributing to our understanding of virus-host CD8+ T-cell interaction in HIV infection.


Assuntos
Infecções por HIV , Síndromes de Imunodeficiência , Síndrome de Imunodeficiência Adquirida dos Símios , Vírus da Imunodeficiência Símia , Animais , Linfócitos T CD8-Positivos , Epitopos de Linfócito T/genética , Antígenos de Histocompatibilidade Classe I/genética , Macaca mulatta , Mutação , Síndrome de Imunodeficiência Adquirida dos Símios/genética , Vírus da Imunodeficiência Símia/genética
4.
Int J Infect Dis ; 81: 231-234, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30776545

RESUMO

OBJECTIVE: To demonstrate the feasibility of applying next-generation sequencing (NGS) in medium-resource reference laboratories in Africa to enhance global disease surveillance. METHODS: A training program was developed to support implementation of NGS at Noguchi Memorial Institute for Medical Research (NMIMR), University of Ghana. The program was divided into two training stages, first at the Centers for Disease Control and Prevention (CDC) in Atlanta, GA, followed by on-site training at NMIMR for a larger cohort of scientists. RESULTS: Self-assessment scores for topics covered during the NGS training program were higher post-training relative to pre-training. During the NGS Training II session at NMIMR, six enterovirus isolates from acute flaccid paralysis cases in Ghana were successfully sequenced by trainees, including two echovirus 6, two echovirus 11 and one echovirus 13. Another genome was an uncommon type (EV-B84), which has not been reported in Africa since its initial discovery from a Côte d'Ivoire specimen in 2003. CONCLUSIONS: The success at NMIMR provides an example of how to approach transferring of NGS methods to international laboratories. There is great opportunity for collaboration between institutes that have genomics expertise to ensure effectiveness and long-term success of global NGS capacity building programs.


Assuntos
Infecções por Enterovirus/virologia , Enterovirus/isolamento & purificação , Laboratórios/organização & administração , Fortalecimento Institucional , Côte d'Ivoire , Enterovirus/classificação , Enterovirus/genética , Gana , Sequenciamento de Nucleotídeos em Larga Escala , Humanos
5.
Virol J ; 15(1): 143, 2018 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-30223845

RESUMO

BACKGROUND: Antiretrovirals have been available in Ghana since 2003 for HIV-1 positive pregnant women for prevention of mother-to-child transmission (PMTCT). Suboptimal responses to treatment observed post-PMTCT interventions necessitated the need to investigate the profile of viral mutations generated. This study investigated HIV-1 drug resistance profiles in mothers in selected centres in Ghana on treatment with a history of prophylaxis. METHODS: Genotypic Drug Resistance Testing for HIV-1 was carried out. Subtyping was done by phylogenetic analysis and Stanford HIV Database programme was used for drug resistance analysis and interpretation. To compare the significance between the different groups and the emergence of drug resistance mutations, p values were used. RESULTS: Participants who had prophylaxis before treatment, those who had treatment without prophylaxis and those yet to initiate PMTCT showed 32% (8), 5% (3) and 15% (4) HIV-1 drug resistance associated mutations respectively. The differences were significant with p value < 0.05. Resistance Associated Mutations (RAMs) were seen in 14 participants (35%) to nucleoside reverse transcriptase inhibitors (NRTIs) and non-nucleoside reverse transcriptase inhibitors (NNRTIs). The most common NRTI mutation found was M184 V; K103 N and A98G were the most common NNRTI mutations seen. Thymidine Analogue Mutations (TAMs) such as M41 L, K70R and T215Y were found in all the groups; the most common of the TAMs found were M41 L and T215Y. Majority of the subtypes were CRF02_AG (82%). CONCLUSION: In Ghana initiation of uninterrupted treatment upon diagnosis, coupled with drug resistance testing, would produce a better treatment outcome for HIV-1 positive pregnant women.


Assuntos
Fármacos Anti-HIV/farmacologia , Quimioprevenção/estatística & dados numéricos , Farmacorresistência Viral , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Mutação de Sentido Incorreto , Fármacos Anti-HIV/administração & dosagem , Feminino , Genótipo , Gana , Infecções por HIV/prevenção & controle , HIV-1/classificação , HIV-1/genética , HIV-1/isolamento & purificação , Humanos , Mães , Filogenia , Gravidez , Complicações Infecciosas na Gravidez/virologia , Análise de Sequência de DNA , Resultado do Tratamento
6.
BMC Public Health ; 14: 687, 2014 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-24996415

RESUMO

BACKGROUND: Ghana recorded the last case of indigenous wild poliovirus in 1999 but suffered two more outbreaks in 2003 and 2008. Following the World Health Organization (WHO) guidelines, transmission was interrupted through high routine immunisation coverage with live-attenuated oral polio vaccine (OPV), effective acute flaccid paralysis (AFP) surveillance and supplementary immunisation activities (SIA). This article describes the results of a five-year surveillance of AFP in polio-free Ghana, evaluate the surveillance indicators and identify areas that need improvement. METHODS: We investigated 1345 cases of AFP from children aged less than 15 years reported to the Disease Surveillance Department from January 2009 to December 2013. Data on demographic characteristics, vaccination history, clinical presentation and virological investigation on stool specimens collected during investigation were analysed. RESULTS: Of the specimens analysed, 56% were from males and 76.3% were from children less than 5 years of age. Twenty-four percent of the children received up to 3 doses of OPV, 57% received at least 4 doses while the status of 19% was unknown. Core AFP surveillance indicators were partly met for non-polio AFP rate while the WHO target for stool adequacy and timeliness was exceeded over the period of study. All the cases were classified virologically, however no wild polio was found. Sixty-day follow-up was conducted for 56.3% of cases and 8.6% cases classified as compactible with polio. CONCLUSION: Both laboratory and epidemiological surveillance for AFP were efficient and many WHO targets were met. However, due to the risk of poliovirus importation prior to global eradication, longterm surveillance is required to provide a high degree of confidence in prevention of poliovirus infection in Ghana. Thus, efforts should be made to strengthen regional performance and to follow-up on all AFP cases in order to establish proper diagnoses for the causes of the AFP leading to proper care.


Assuntos
Paraplegia/epidemiologia , Vigilância da População , Adolescente , Criança , Pré-Escolar , Fezes/microbiologia , Feminino , Gana/epidemiologia , Humanos , Masculino , Poliomielite/diagnóstico , Poliomielite/epidemiologia , Vacina Antipólio Oral/administração & dosagem , Organização Mundial da Saúde
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