Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
1.
Virol J ; 19(1): 73, 2022 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-35459145

RESUMO

BACKGROUND: Hepatitis C virus (HCV) infection is a blood borne infection that remains potentially transmissible through blood transfusions. Sickle cell disease (SCD) is a common inheritable haemoglobinopathy in Ghana that requires multiple blood transfusions as part of its management. The SCD patient is therefore at a high risk of HCV infection; however, data on the occurrence of HCV in SCD patients has not been documented in Ghana. This study sought to determine the prevalence and genotypes of HCV infection in SCD patients. MATERIALS AND METHODS: This was a cross-sectional study which enrolled 141 sickle-cell disease patients from the Ghana Institute for Clinical Genetics, Korle-Bu Teaching Hospital (KBTH). Patient information was obtained through a structured questionnaire. Aliquots of the plasma obtained was used for both serology with Advanced Quality Rapid Anti-HCV Test Strip and molecular testing by RT-PCR with primers targeting the HCV core gene. The amplified DNA were purified and subjected to phylogenetic analysis to characterize HCV genotypes. RESULTS: Twelve (9%) out of the 141 patients were sero-positive for HCV total antibodies. HCV RNA was amplified from 8 (6%) out of the total number of patients' samples. One of the 12 sero-positives was HCV RNA positive. Five (63%) out of the 8 HCV RNA positive samples were successfully sequenced. The phylogenetic tree constructed with the study and GenBank reference sequences, clustered all five study sequences into HCV genotype 1. CONCLUSION: The HCV seroprevalence of 9% among sickle cell disease patients is higher than reported for the general Ghanaian population which is 3%. Genotype 1 is the common HCV genotype infecting SCD patients. Sickle cell disease is likely to be a high-risk group for HCV inapparent infections in Ghana as seroprevalence does not correlate with viremia. However, even with higher seroprevalence, the group must be given priority in resource allocation for preventive, diagnostic and therapeutic strategies.


Assuntos
Anemia Falciforme , Hepatite C , Anemia Falciforme/complicações , Anemia Falciforme/epidemiologia , Anemia Falciforme/genética , Estudos Transversais , Genótipo , Gana/epidemiologia , Hepacivirus/genética , Hepatite C/epidemiologia , Anticorpos Anti-Hepatite C , Hospitais de Ensino , Humanos , Filogenia , Prevalência , RNA , Estudos Soroepidemiológicos
2.
Arch Virol ; 167(1): 123-130, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34757503

RESUMO

Ticks are blood-sucking arthropods that transmit many pathogens, including arboviruses. Arboviruses transmitted by ticks are generally referred to as tick-borne viruses (TBVs). TBVs are known to cause diseases in humans, pets, and livestock. There is, however, very limited information on the occurrence and distribution of TBVs in sub-Saharan Africa. This study was designed to determine the presence and distribution of ticks infesting dogs and cattle in Ghana, as well as to identify the tick-borne or tick-associated viruses they harbour. A more diverse population of ticks was found to infest cattle (three genera) relative to those infesting dogs (one genus). Six phleboviruses and an orthonairovirus were detected in tick pools screened by RT-PCR. Subsequent sequence analysis revealed two distinct phleboviruses and the previously reported Odaw virus in ticks collected from dogs and a virus (16GH-T27) most closely related to four unclassified phleboviruses in ticks collected from cattle. The virus 16GH-T27 was considered a strain of Balambala tick virus (BTV) and named BTV strain 16GH-T27. Next-generation sequencing analysis of the BTV-positive tick pool detected only the L and S segments. Phylogenetic analysis revealed that BTV clustered with viruses previously defined as M-segment-deficient phleboviruses. The orthonairovirus detected in ticks collected from cattle was confirmed to be the medically important Dugbe virus. Furthermore, we discuss the importance of understanding the presence and distribution of ticks and TBVs in disease prevention and mitigation and the implications for public health. Our findings contribute to the knowledge pool on TBVs and tick-associated viruses.


Assuntos
Phlebovirus , Doenças Transmitidas por Carrapatos , Carrapatos , Animais , Bovinos , Cães , Gana/epidemiologia , Filogenia , Vírus Satélites , Doenças Transmitidas por Carrapatos/epidemiologia , Doenças Transmitidas por Carrapatos/veterinária
3.
Antimicrob Agents Chemother ; 60(9): 5608-11, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27381400

RESUMO

We found a heterozygous C2857T mutation (R953C) in polymerase gamma (Pol-γ) in an HIV-infected patient with mitochondrial toxicity. The R953C Pol-γ mutant binding affinity for dCTP is 8-fold less than that of the wild type. The R953C mutant shows a 4-fold decrease in discrimination of analog nucleotides relative to the wild type. R953 is located on the "O-helix" that forms the substrate deoxynucleoside triphosphate (dNTP) binding site; the interactions of R953 with E1056 and Y986 may stabilize the O-helix and affect polymerase activity.


Assuntos
Antirretrovirais/uso terapêutico , DNA Polimerase Dirigida por DNA/genética , Mitocôndrias/genética , Mutação/genética , Sequência de Aminoácidos , Sítios de Ligação , DNA Polimerase gama , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/genética , Humanos , Masculino , Pessoa de Meia-Idade , Conformação Proteica
4.
Pharmaceutics ; 14(7)2022 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-35890248

RESUMO

Our understanding of HIV infection has greatly advanced since the discovery of the virus in 1983. Treatment options have improved the quality of life of people living with HIV/AIDS, turning it from a fatal disease into a chronic, manageable infection. Despite all this progress, a cure remains elusive. A major barrier to attaining an HIV cure is the presence of the latent viral reservoir, which is established early in infection and persists for the lifetime of the host, even during prolonged anti-viral therapy. Different cure strategies are currently being explored to eliminate or suppress this reservoir. Several studies have shown that a functional cure may be achieved by preventing infection and also inhibiting reactivation of the virus from the latent reservoir. Here, we briefly describe the main HIV cure strategies, focussing on the use of RNA therapeutics, including small interfering RNA (siRNA) to maintain HIV permanently in a state of super latency, and CRISPR gRNA to excise the latent reservoir. A challenge with progressing RNA therapeutics to the clinic is achieving effective delivery into the host cell. This review covers recent nanotechnological strategies for siRNA delivery using liposomes, N-acetylgalactosamine conjugation, inorganic nanoparticles and polymer-based nanocapsules. We further discuss the opportunities and challenges of those strategies for HIV treatment.

5.
PLoS One ; 16(1): e0244507, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33411715

RESUMO

BACKGROUND: Within HIV/HBV infected patients, an increase in HDV infection has been observed; there is inadequate information on HDV prevalence as well as virologic profile in Ghana. This study sought to determine the presence of HDV in HIV/HBV co-infected patients in Ghana. METHODS: This was a longitudinal purposive study which enrolled 113 HIV/HBV co-infected patients attending clinic at Korle-Bu Teaching Hospital (KBTH) in Accra, Ghana. After consenting, 5 mL whole blood was collected at two-time points (baseline and 4-6 months afterwards). The sera obtained were tested to confirm the presence of HIV, HBV antibodies and/or antigens, and HBV DNA. Antibodies and viral RNA were also determined for HDV. Amplified HBV DNA and HDV RNA were sequenced and phylogenetic analysis carried out with reference sequences from the GenBank to establish the genotypes. RESULTS: Of the 113 samples tested 63 (55.7%) were females and 50 (44.25%) were males with a median age of 45 years. A total of 100 (88.5%) samples had detectable HBV surface antigen (HBsAg), and 32 out of the 113 had detectable HBV DNA. Nucleotide sequences were obtained for 15 and 2 samples of HBV and HDV, respectively. Phylogenetic analysis was predominantly genotype E for the HBVs and genotype 1 for the HDVs. Of the 13 samples that were HBsAg unreactive, 4 (30.8%) had detectable HBV DNA suggesting the incidence of occult HBV infections. The percentage occurrence of HDV in this study was observed to be 3.54. CONCLUSION: Our data suggest the presence and circulation of HDV and incidence of occult HBV infection in HIV/HBV co-infected patients in Ghana. This informs health staff and makes it imperative to look out for the presence of HDV and occult HBV in HIV/HBV co-infected patients presenting with potential risk of liver cancers and HBV transmission through haemodialysis and blood transfusions.


Assuntos
Coinfecção/virologia , Infecções por HIV/virologia , Vírus da Hepatite B/isolamento & purificação , Vírus da Hepatite B/fisiologia , Hepatite B/virologia , Vírus Delta da Hepatite/isolamento & purificação , Adulto , Alanina Transaminase/metabolismo , Aspartato Aminotransferases/metabolismo , Coinfecção/enzimologia , Feminino , Técnicas de Genotipagem , Gana , Infecções por HIV/enzimologia , Hepatite B/enzimologia , Vírus da Hepatite B/genética , Vírus Delta da Hepatite/fisiologia , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Adulto Jovem
6.
Viruses ; 12(2)2020 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-32012771

RESUMO

Entomological surveillance is one of the tools used in monitoring and controlling vector-borne diseases. However, the use of entomological surveillance for arboviral infection vector control is often dependent on finding infected individuals. Although this method may suffice in highly endemic areas, it is not as effective in controlling the spread of diseases in low endemic and non-endemic areas. In this study, we examined the efficiency of using entomological markers to assess the status and risk of arbovirus infection in Ghana, which is considered a non-endemic country, by combining mosquito surveillance with virus isolation and detection. This study reports the presence of cryptic species of mosquitoes in Ghana, demonstrating the need to combine morphological identification and molecular techniques in mosquito surveillance. Furthermore, although no medically important viruses were detected, the importance of insect-specific viruses in understanding virus evolution and arbovirus transmission is discussed. This study reports the first mutualistic relationship between dengue virus and the double-stranded RNA Aedes aegypti totivirus. Finally, this study discusses the complexity of the virome of Aedes and Culex mosquitoes and its implication for arbovirus transmission.


Assuntos
Aedes/virologia , Infecções por Arbovirus/transmissão , Arbovírus/genética , Culex/virologia , Mosquitos Vetores/virologia , Viroma , Animais , Infecções por Arbovirus/epidemiologia , Arbovírus/isolamento & purificação , Dengue/epidemiologia , Vírus da Dengue/genética , Vírus da Dengue/patogenicidade , Entomologia/métodos , Feminino , Gana/epidemiologia , Masculino , Fatores de Risco , Doenças Transmitidas por Vetores/epidemiologia , Doenças Transmitidas por Vetores/virologia
7.
BMC Res Notes ; 12(1): 326, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31182146

RESUMO

OBJECTIVE: Increase in the evidence of global occurrence of Zika viral infection suggests that in Africa the circulation of the virus which causes 80% of asymptomatic infection could be undetected and/or overlooked. We sought to serologically detect Zika virus infection in febrile patients at Greater Accra Regional Hospital, Ghana. RESULTS: Of the 160 patient serum samples analyzed, 33 were found to have antibodies against Zika virus infection. Among the sero-positives 30 (91%) of the cases were anti-Zika virus IgM with the 21-30-year age group recording the highest number of 8 (26%) and 2 (7%) cases being the least for the 61 years and above age group. All sero-positive febrile patients developed at least one symptom consistent with Zika virus infection: 33 (100%) fever, 25 (76%) muscle pain, 24 (73%) joint pain, and conjunctivitis 2 (6%). Digestive symptoms recorded include 16 (49%) nausea, 12 (36%) vomiting and diarrhea 18 (55%). In addition, 28 (85%) loss of appetite, 14 (75%) rapid respiration and chest pain 15 (42%) were reported by seropositive febrile patients. Our data indicates exposure to Zika virus which suggests the possible circulation of the virus among febrile patients in Ghana with a sero-prevalence rate of 20.6%.


Assuntos
Anticorpos Antivirais/sangue , Artralgia/imunologia , Febre/imunologia , Mialgia/imunologia , Infecção por Zika virus/imunologia , Zika virus/imunologia , Adolescente , Adulto , Idoso , Artralgia/diagnóstico , Artralgia/epidemiologia , Artralgia/fisiopatologia , Criança , Pré-Escolar , Conjuntivite Viral/diagnóstico , Conjuntivite Viral/epidemiologia , Conjuntivite Viral/imunologia , Conjuntivite Viral/fisiopatologia , Estudos Transversais , Diarreia/diagnóstico , Diarreia/epidemiologia , Diarreia/imunologia , Diarreia/fisiopatologia , Feminino , Febre/diagnóstico , Febre/epidemiologia , Febre/fisiopatologia , Gana/epidemiologia , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Mialgia/diagnóstico , Mialgia/epidemiologia , Mialgia/fisiopatologia , Náusea/diagnóstico , Náusea/epidemiologia , Náusea/imunologia , Náusea/fisiopatologia , Estudos Soroepidemiológicos , Vômito/diagnóstico , Vômito/epidemiologia , Vômito/imunologia , Vômito/fisiopatologia , Zika virus/crescimento & desenvolvimento , Zika virus/patogenicidade , Infecção por Zika virus/diagnóstico , Infecção por Zika virus/epidemiologia , Infecção por Zika virus/fisiopatologia
8.
Medicine (Baltimore) ; 98(6): e14313, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30732150

RESUMO

Antiretroviral therapy (ART) and drug resistance studies worldwide have focused almost exclusively on human immunodeficiency virus type 1 (HIV-1). As a result, there is limited information on ART and drug resistance in HIV-2 patients. In Ghana, the HIV epidemic is characterized by the domination of HIV-1, with cocirculating HIV-2. We, therefore, sought to determine viral load and drug resistance mutations in HIV-2 patients to inform the clinical management of such individuals in Ghana.We used purposive sampling to collect blood from 16 consented patients, confirmed as HIV-2 or HIV-1/2 dual infections by serology. A 2-step real-time RT-PCR assay was used to determine plasma HIV-2 RNA viral loads. For drug resistance testing, nucleic acids were extracted from plasma and peripheral blood mononuclear cells. The reverse transcriptase and protease genes of HIV-2 were amplified, sequenced and analyzed for drug resistance mutations and HIV-2 group.HIV-2 viral load was detected in 9 of 16 patients. Six of these had quantifiable viral loads (range: 2.62-5.45 log IU/mL) while 3 had viral loads below the limit of quantification. Sequences were generated from 7 out of 16 samples. Five of these were classified as HIV-2 group B and 2 as HIV-2 group A. HIV-2 drug resistance mutations (M184V, K65R, Y115F) were identified in 1 patient.This study is the first to report HIV-2 viral load and drug resistance mutations in HIV-2 strains from Ghana. The results indicate the need for continuous monitoring of drug resistance among HIV-2- infected patients to improve their clinical management.


Assuntos
Farmacorresistência Viral/genética , Infecções por HIV/tratamento farmacológico , HIV-1/genética , HIV-2/genética , Mutação/genética , Carga Viral , Adulto , Idoso , Fármacos Anti-HIV/uso terapêutico , Estudos Transversais , Feminino , Gana , Infecções por HIV/complicações , Infecções por HIV/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
9.
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
10.
PLoS One ; 13(12): e0208907, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30566466

RESUMO

Dengue fever is known to be one of the most common arthropod-borne viral infectious diseases of public health importance. The disease is now endemic in more than 100 countries in Africa, the Americas, the Eastern Mediterranean, Southeast Asia and the Western Pacific with an estimated two fifths of the world's population being at risk. The notable endemic viral hemorrhagic fevers (VHFs) found in West Africa, including yellow fever, Lassa fever, Rift Valley fever, dengue fever and until recently Ebola have been responsible for most outbreaks with fatal consequences. These VHFs usually produce unclear acute febrile illness, especially in the acute phase of infection. In this study we detected the presence of 2 different serotypes (DENV-2 and DENV-3) of Dengue virus in 4 sera of 150 patients clinically suspected of Ebola virus disease during the Ebola Virus Disease (EVD) outbreak in West Africa with the use of serological and molecular test assays. Sequence data was successfully generated for DENV-3 and phylogenetic analysis of the envelope gene showed that the DENV-3 sequences had close homology with DENV-3 sequences from Senegal and India. This study documents molecular evidence of an indigenous Dengue fever viral infection in Ghana and therefore necessitates the need to have an efficient surveillance system to rapidly detect and control the dissemination of the different serotypes in the population which has the potential to cause outbreaks of dengue hemorrhagic fevers.


Assuntos
Vírus da Dengue/genética , Dengue , Ebolavirus/genética , Doença pelo Vírus Ebola , Dengue/epidemiologia , Dengue/genética , Dengue/virologia , Surtos de Doenças , Feminino , Gana/epidemiologia , Doença pelo Vírus Ebola/epidemiologia , Doença pelo Vírus Ebola/genética , Doença pelo Vírus Ebola/virologia , Humanos , Masculino
11.
Ticks Tick Borne Dis ; 8(4): 640-645, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28479064

RESUMO

Ticks are ectoparasites that transmit various types of human and animal pathogens. In particular, emerging and re-emerging diseases caused by tick-borne viruses are public health concerns around the world. However, in many countries of the sub-Saharan African region, epidemiological information on tick-borne viral infections is limited, and their prevalence and distribution remain largely unknown. In this study, we conducted surveillance on ticks to detect medically important tick-borne bunyaviruses in three study sites in and near to Accra, the capital city of Ghana, in 2015. Domestic dogs and cattle were surveyed and were found to be infested with various tick species belonging to the genera Rhipicephalus, Amblyomma and Haemaphysalis. Importantly, we detected a novel putative phlebovirus in Rhipicephalus ticks, and successfully isolated a new strain of Dugbe virus from Am. variegatum ticks. To our knowledge, this is the first report of tick-associated viruses in Ghana other than Crimean-Congo hemorrhagic fever virus.


Assuntos
Doenças dos Bovinos/epidemiologia , Doenças do Cão/epidemiologia , Ixodidae/virologia , Vírus da Doença do Carneiro de Nairobi/isolamento & purificação , Phlebovirus/isolamento & purificação , Infestações por Carrapato/veterinária , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Doenças do Cão/parasitologia , Cães , Feminino , Gana/epidemiologia , Ixodidae/crescimento & desenvolvimento , Masculino , Ninfa/crescimento & desenvolvimento , Ninfa/virologia , Phlebovirus/classificação , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/parasitologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA