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Dengue fever is expanding as a global public health threat including countries within Africa. For the past few decades, Cameroon has experienced sporadic cases of arboviral infections including dengue fever. Here, we conducted genomic analyses to investigate the origin and phylogenetic profile of Cameroon DENV-1 outbreak strains and predict the impact of emerging therapeutics on these strains. Bayesian and maximum-likelihood phylogenetic inference approaches were employed in virus evolutionary analyses. An in silico analysis was performed to assess the divergence in immunotherapeutic and vaccine targets in the new genomes. Six complete DENV-1 genomes were generated from 50 samples that met a clinical definition for DENV infection. Phylogenetic analyses revealed that the strains from the current study belong to a sub-lineage of DENV-1 genotype V and form a monophyletic taxon with a 2012 strain from Gabon. The most recent common ancestor (TMRCA) of the Cameroon and Gabon strains was estimated to have existed around 2008. Comparing our sequences to the vaccine strains, 19 and 15 amino acid (aa) substitutions were observed in the immuno-protective prM-E protein segments of the Dengvaxia® and TetraVax-DV-TV003 vaccines, respectively. Epitope mapping revealed mismatches in aa residues at positions E155 and E161 located in the epitope of the human anti-DENV-1 monoclonal antibody HMAb 1F4. The new DENV strains constitute a conserved genomic pool of viruses endemic to the Central African region that needs prospective monitoring to track local viral evolution. Further work is needed to ascertain the performance of emerging therapeutics in DENV strains from the African region.
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Virus del Dengue , Dengue , Vacunas , Humanos , Virus del Dengue/genética , Dengue/epidemiología , Filogenia , Camerún/epidemiología , Teorema de Bayes , Estudios Prospectivos , Secuenciación Completa del Genoma , Genotipo , Brotes de EnfermedadesRESUMEN
To assess dynamics of SARS-CoV-2 in Greater Accra Region, Ghana, we analyzed SARS-CoV-2 genomic sequences from persons in the community and returning from international travel. The Accra Metropolitan District was a major origin of virus spread to other districts and should be a primary focus for interventions against future infectious disease outbreaks.
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COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/epidemiología , Ghana/epidemiología , Evolución Biológica , Brotes de EnfermedadesRESUMEN
Objective: This study aimed to determine the duration of SARS-CoV-2 clearance in persons in Ghana. The research question was whether the duration of virus clearance in Ghana matched the 14 days recommended by the World Health Organization (WHO); this had direct implications for transmission, which was key in managing the COVID-19 pandemic. Design: This was a retrospective analytical study. Setting: All facilities that submitted clinical specimens to Noguchi Memorial Institute for Medical Research (NMIMR) for SARS-CoV-2 diagnosis between March to June 2020 were included in the study. Interventions: Samples from 480 persons who tested positive for SARS-CoV-2 by RT-PCR from March to June 2020 at NMIMR and submitted at least two follow-up samples were retrospectively analysed. Individuals with two consecutive negative RT-PCR retesting results were considered to have cleared SARS-CoV-2. Results: The median time from the initial positive test to virus clearance was 20 days (IQR: 5-56 days). This was six days longer than the WHO-recommended 14 days, after which infected persons could be de-isolated. Sputum and nasopharyngeal swabs proved more sensitive for detecting viral RNA as the infection progressed. At a significance level of 0.05, age and sex did not seem to influence the time to SARS-CoV-2 clearance. Conclusions: The median time to SARS-CoV-2 clearance in this study was 20 days, suggesting that SARS-CoV-2 infected persons in Ghana take longer to clear the virus. This finding calls for further investigations into whether patients who remain PCR positive continue to be infectious and inform isolation practices in Ghana. Funding: The study was supported by the Ministry of Health/ Ghana Health Service through the provision of laboratory supplies, the US Naval Medical Research Unit #3, the World Health Organization, the Jack Ma Foundation and the Virology Department of Noguchi Memorial Institute for Medical Research, University of Ghana. Research projects within Noguchi Memorial Institute for Medical Research contributed reagents and laboratory consumables. However, the authors alone are responsible for the contents of this manuscript.
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COVID-19 , SARS-CoV-2 , Humanos , COVID-19/diagnóstico , COVID-19/epidemiología , Estudios Retrospectivos , Prueba de COVID-19 , Pandemias , Ghana/epidemiologíaRESUMEN
Objective: This study aimed to determine the duration of SARS-CoV-2 clearance in persons in Ghana. The research question was whether the duration of virus clearance in Ghana matched the 14 days recommended by the World Health Organization (WHO); this had direct implications for transmission, which was key in managing the COVID-19 pandemic. Design: This was a retrospective analytical study. Setting: All facilities that submitted clinical specimens to Noguchi Memorial Institute for Medical Research (NMIMR) for SARS-CoV-2 diagnosis between March to June 2020 were included in the study. Interventions: Samples from 480 persons who tested positive for SARS-CoV-2 by RT-PCR from March to June 2020 at NMIMR and submitted at least two follow-up samples were retrospectively analysed. Individuals with two consecutive negative RT-PCR retesting results were considered to have cleared SARS-CoV-2. Results: The median time from the initial positive test to virus clearance was 20 days (IQR: 5-56 days). This was six days longer than the WHO-recommended 14 days, after which infected persons could be de-isolated. Sputum and nasopharyngeal swabs proved more sensitive for detecting viral RNA as the infection progressed. At a significance level of 0.05, age and sex did not seem to influence the time to SARS-CoV-2 clearance. Conclusions: The median time to SARS-CoV-2 clearance in this study was 20 days, suggesting that SARS-CoV-2 infected persons in Ghana take longer to clear the virus. This finding calls for further investigations into whether patients who remain PCR positive continue to be infectious and inform isolation practices in Ghana.
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Humanos , Masculino , Femenino , Signos y Síntomas , Coronavirus del Síndrome Respiratorio de Oriente Medio , SARS-CoV-2 , COVID-19 , Prueba de Ácido Nucleico para COVID-19RESUMEN
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 upper-torso 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.
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Infecciones Bacterianas , Coinfección , Gripe Humana , Neoplasias , Infecciones del Sistema Respiratorio , Adolescente , Adulto , Anciano , Bacterias/genética , Infecciones Bacterianas/epidemiología , Infecciones Bacterianas/etiología , Coinfección/epidemiología , Femenino , Ghana/epidemiología , Humanos , Lactante , Gripe Humana/complicaciones , Gripe Humana/epidemiología , Masculino , Persona de Mediana Edad , Neoplasias/complicaciones , Neoplasias/radioterapia , Estudios Prospectivos , Infecciones del Sistema Respiratorio/epidemiología , Staphylococcus aureus , Streptococcus pneumoniae , Adulto JovenRESUMEN
In late 2019, a novel coronavirus, the SARS-CoV-2 outbreak was identified in Wuhan, China and later spread to every corner of the globe. Whilst the number of infection-induced deaths in Ghana, West Africa are minimal when compared with the rest of the world, the impact on the local health service is still significant. Compartmental models are a useful framework for investigating transmission of diseases in societies. To understand how the infection will spread and how to limit the outbreak. We have developed a modified SEIR compartmental model with nine compartments (CoVCom9) to describe the dynamics of SARS-CoV-2 transmission in Ghana. We have carried out a detailed mathematical analysis of the CoVCom9, including the derivation of the basic reproduction number, R 0 . In particular, we have shown that the disease-free equilibrium is globally asymptotically stable when R 0 < 1 via a candidate Lyapunov function. Using the SARS-CoV-2 reported data for confirmed-positive cases and deaths from March 13 to August 10, 2020, we have parametrised the CoVCom9 model. The results of this fit show good agreement with data. We used Latin hypercube sampling-rank correlation coefficient (LHS-PRCC) to investigate the uncertainty and sensitivity of R 0 since the results derived are significant in controlling the spread of SARS-CoV-2. We estimate that over this five month period, the basic reproduction number is given by R 0 = 3 . 110 , with the 95% confidence interval being 2 . 042 ≤ R 0 ≤ 3 . 240 , and the mean value being R 0 = 2 . 623 . Of the 32 parameters in the model, we find that just six have a significant influence on R 0 , these include the rate of testing, where an increasing testing rate contributes to the reduction of R 0 .
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Background: The spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by asymptomatic individuals has been reported since the early stages of the coronavirus disease 2019 (COVID-19) outbreak in various parts of the world. However, there are limited data regarding SARS-CoV-2 among asymptomatic individuals in Ghana. The aim of the study was to use test data of prospective travelers from Ghana as a proxy to estimate the contribution of asymptomatic cases to the spread of COVID-19. Methods: The study analyzed the SARS-CoV-2 PCR test data of clients whose purpose for testing was classified as "Travel" at the COVID-19 walk-in test center of the Noguchi Memorial Institute for Medical Research (NMIMR) from July 2020 to July 2021. These individuals requesting tests for travel generally had no clinical symptoms of COVID-19 at the time of testing. Data were processed and analyzed using Microsoft Excel office 16 and STATA version 16. Descriptive statistics were used to summarize data on test and demographic characteristics. Results: Out of 42,997 samples tested at the center within that period, 28,384 (66.0%) were classified as "Travel" tests. Of these, 1,900 (6.7%) tested positive for SARS-CoV-2. The majority (64.8%) of the "Travel" tests were requested by men. The men recorded a SARS-CoV-2 positivity of 6.9% compared to the 6.4% observed among women. Test requests for SARS-CoV-2 were received from all regions of Ghana, with a majority (83.3%) received from the Greater Accra Region. Although the Eastern region recorded the highest SARS-CoV-2 positivity rate of 8.35%, the Greater Accra region contributed 81% to the total number of SARS-CoV-2 positive cases detected within the period of study. Conclusion: Our study found substantial SARS-CoV-2 positivity among asymptomatic individuals who, without the requirement for a negative SARS-CoV-2 result for travel, would have no reason to test. These asymptomatic SARS-CoV-2-infected individuals could have traveled to other countries and unintentionally spread the virus. Our findings call for enhanced tracing and testing of asymptomatic contacts of individuals who tested positive for SARS-CoV-2.
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COVID-19 , Masculino , Humanos , Femenino , COVID-19/diagnóstico , COVID-19/epidemiología , SARS-CoV-2 , Estudios Transversales , Ghana/epidemiología , Estudios ProspectivosRESUMEN
BACKGROUND: Chikungunya virus (CHIKV) is a re-emerging arbovirus associated with sporadic outbreaks in Cameroon since 2006. Viral whole genomes were generated to analyze the origins of evolutionary lineages, the potential of emergence/re-emergence, and to infer transmission dynamics of recent Cameroon CHIKV outbreak strains. METHODS: Samples collected between 2016 and 2019 during CHIKV outbreaks in Cameroon were screened for CHIKV using reverse transcription PCR (RT-PCR), followed by whole genome sequencing of positive samples. RESULTS: Three coding-complete CHIKV genomes were obtained from samples, which belong to an emerging sub-lineage of the East/Central/South African genotype and formed a monophyletic taxon with previous Central African strains. This clade, which we have named the new Central African clade, appears to be evolving at 3.0 × 10-4 nucleotide substitutions per site per year (95% highest posterior density (HPD) interval of 1.94 × 10-4 to 4.1 × 10-4). Notably, mutations in the envelope proteins (E1-A226V, E2-L210Q, and E2-I211T), which are known to enhance CHIKV adaptability and infectious potential in Aedes albopictus, were present in all strains and mapped to established high-density Ae. albopictus populations. CONCLUSIONS: These new CHIKV strains constitute a conserved genomic pool of an emerging sub-lineage, reflecting a putative vector host adaptation to Ae. albopictus, which has practically displaced Aedes aegypti from select regions of Cameroon.
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Aedes , Fiebre Chikungunya , Virus Chikungunya , Animales , Camerún/epidemiología , Fiebre Chikungunya/epidemiología , Virus Chikungunya/genética , Brotes de Enfermedades , Humanos , Mosquitos Vectores , Mutación , Filogenia , Estudios RetrospectivosRESUMEN
BACKGROUND: The impact of Ebola virus disease (EVD) is devastating with concomitant high fatalities. Currently, various drugs and vaccines are at different stages of development, corroborating the need to identify new therapeutic molecules. The VP24 protein of the Ebola virus (EBOV) plays a key role in the pathology and replication of the EVD. The VP24 protein interferes with the host immune response to viral infections and promotes nucleocapsid formation, thus making it a viable drug target. This study sought to identify putative lead compounds from the African flora with potential to inhibit the activity of the EBOV VP24 protein using pharmacoinformatics and molecular docking. METHODS: An integrated library of 7675 natural products originating from Africa obtained from the AfroDB and NANPDB databases, as well as known inhibitors were screened against VP24 (PDB ID: 4M0Q) utilising AutoDock Vina after energy minimization using GROMACS. The top 19 compounds were physicochemically and pharmacologically profiled using ADMET Predictor™, SwissADME and DataWarrior. The mechanisms of binding between the molecules and EBOV VP24 were characterised using LigPlot+. The performance of the molecular docking was evaluated by generating a receiver operating characteristic (ROC) by screening known inhibitors and decoys against EBOV VP24. The prediction of activity spectra for substances (PASS) and machine learning-based Open Bayesian models were used to predict the anti-viral and anti-Ebola activity of the molecules, respectively. RESULTS: Four natural products, namely, ZINC000095486070, ZINC000003594643, ZINC000095486008 and sarcophine were found to be potential EBOV VP24-inhibitiory molecules. The molecular docking results showed that ZINC000095486070 had high binding affinity of -9.7â¯kcal/mol with EBOV VP24, which was greater than those of the known VP24-inhibitors used as standards in the study including Ouabain, Nilotinib, Clomiphene, Torimefene, Miglustat and BCX4430. The area under the curve of the generated ROC for evaluating the performance of the molecular docking was 0.77, which was considered acceptable. The predicted promising molecules were also validated using induced-fit docking with the receptor using Schrödinger and molecular mechanics Poisson-Boltzmann surface area (MM-PBSA) calculations. The molecules had better binding mechanisms and were pharmacologically profiled to have plausible efficacies, negligible toxicity as well as suitable for designing anti-Ebola scaffolds. ZINC000095486008 and sarcophine (NANPDB135) were predicted to possess anti-viral activity, while ZINC000095486070 and ZINC000003594643 to be anti-Ebola compounds. CONCLUSION: The identified compounds are potential inhibitors worthy of further development as EBOV biotherapeutic agents. The scaffolds of the compounds could also serve as building blocks for designing novel Ebola inhibitors.
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Antivirales/química , Ebolavirus/química , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Fitoquímicos/química , Proteínas Virales , Antivirales/uso terapéutico , Fiebre Hemorrágica Ebola/tratamiento farmacológico , Humanos , Fitoquímicos/uso terapéutico , Proteínas Virales/antagonistas & inhibidores , Proteínas Virales/químicaRESUMEN
BACKGROUND: Acute respiratory tract infections of viral origin remain a leading cause of morbidity, mortality and economic loss regardless of age or gender. A small number of acute respiratory tract infection cases caused by enterovirus D68 (EV-D68) have been reported regularly to Centers for Disease Control and Prevention since 1987 by countries in North America, Europe and Asia. However, in 2014 and 2015, the number of reported confirmed EV-D68 infections was much greater than in previous years. The National Influenza Centre (NIC), Ghana carries out surveillance of respiratory infections, focusing on those caused by influenza virus; however, there is inadequate information on other viruses causing respiratory infections in Ghana, including EV-D68. OBJECTIVES: To investigate the association of EV-D68 with Severe Acute Respiratory Infections (SARI) and Influenza-Like Illness (ILI) in Ghana. METHODS: This was a retrospective cross-sectional study which involved archived human respiratory specimens stored at -80 °C at the NIC from 2014 to 2015. Using a random sampling method, oropharyngeal and nasopharyngeal swabs from patients with SARI and ILI that were negative by real-time PCR for human influenza viruses were screened for EV-D68 using real-time reverse transcription-polymerase chain reaction (rRT-PCR). RESULTS: Enterovirus D68 was detected in 4 (2.2%) out of 182 SARI samples tested. EV-D68 was detected in children younger than 5 years (4 - 100% of positives) and was not detected in children older than 5 years. Enterovirus D68 was detected more frequently in SARI cases (3%) than in ILI cases (1.2%). CONCLUSION: This study has shown for the first time the presence of EV-D68 in acute respiratory infections in Ghana. The results confirmed minimal EV-D68 circulation in the Ghanaian population.
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[This corrects the article DOI: 10.1371/journal.pone.0215224.].
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Rodents serve as reservoirs and/or vectors for several human infections of high morbidity and mortality in the tropics. Population growth and demographic shifts over the years have increased contact with these mammals, thereby increasing opportunities for disease transmission. In Africa, the burden of rodent-borne diseases is not well described. To investigate human seroprevalence of selected rodent-borne pathogens, sera from 657 healthy adults in ten rural communities in Ghana were analyzed. An in-house enzyme-linked immunosorbent assay (ELISA), for immunoglobulin G (IgG) antibodies to Lassa virus was positive in 34 (5%) of the human samples. Using commercial kits, antibodies to hantavirus serotypes, Puumala and Dobrava, and Leptospira bacteria were detected in 11%, 12% and 21% of the human samples, respectively. Forty percent of residents in rural farming communities in Ghana have measurable antibodies to at least one of the rodent-borne pathogens tested, including antibodies to viral hemorrhagic fever viruses. The high seroprevalence found in rural Ghana to rodent-borne pathogens associated with both sporadic cases and larger disease outbreaks will help define disease threats and inform public health policy to reduce disease burden in underserved populations and deter larger outbreaks.
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Reservorios de Enfermedades/microbiología , Reservorios de Enfermedades/virología , Vectores de Enfermedades , Roedores/microbiología , Roedores/virología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Agricultura , Animales , Anticuerpos Antibacterianos/sangre , Anticuerpos Antivirales/sangre , Femenino , Ghana/epidemiología , Orthohantavirus/inmunología , Infecciones por Hantavirus/epidemiología , Fiebres Hemorrágicas Virales/epidemiología , Humanos , Fiebre de Lassa/epidemiología , Virus Lassa/inmunología , Leptospira/inmunología , Leptospirosis/epidemiología , Masculino , Persona de Mediana Edad , Población Rural , Estudios Seroepidemiológicos , Adulto Joven , Zoonosis/epidemiologíaRESUMEN
Background: Acute respiratory tract infections of viral origin remain a leading cause of morbidity, mortality and economic loss regardless of age or gender. A small number of acute respiratory tract infection cases caused by enterovirus D68 (EV-D68) have been reported regularly to Centers for Disease Control and Prevention since 1987 by countries in North America, Europe and Asia. However, in 2014 and 2015, the number of reported confirmed EV-D68 infections was much greater than in previous years. The National Influenza Centre (NIC), Ghana carries out surveillance of respiratory infections, focusing on those caused by influenza virus; however, there is inadequate information on other viruses causing respiratory infections in Ghana, including EV-D68.Objectives: To investigate the association of EV-D68 with Severe Acute Respiratory Infections (SARI) and Influenza-Like Illness (ILI) in Ghana.Methods: This was a retrospective cross-sectional study which involved archived human respiratory specimens stored at 80 °C at the NIC from 2014 to 2015. Using a random sampling method, oropharyngeal and nasopharyngeal swabs from patients with SARI and ILI that were negative by real-time PCR for human influenza viruses were screened for EV-D68 using real-time reverse transcription-polymerase chain reaction (rRT-PCR).Results: Enterovirus D68 was detected in 4 (2.2%) out of 182 SARI samples tested. EV-D68 was detected in children younger than 5 years (4 100% of positives) and was not detected in children older than 5 years. Enterovirus D68 was detected more frequently in SARI cases (3%) than in ILI cases (1.2%).Conclusion: This study has shown for the first time the presence of EV-D68 in acute respiratory infections in Ghana. The results confirmed minimal EV-D68 circulation in the Ghanaian population
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Niño , Enterovirus Humano D , Ghana , Infecciones del Sistema Respiratorio , Transcripción ReversaRESUMEN
We report new molecular evidence of locally acquired dengue virus infections in Ghana. We detected dengue viral RNA among children with suspected malaria by using a multipathogen real-time PCR. Subsequent sequence analysis revealed a close relationship with dengue virus serotype 2, which was implicated in a 2016 outbreak in Burkina Faso.
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ADN Protozoario/genética , Virus del Dengue/genética , Dengue/epidemiología , Malaria/epidemiología , Plasmodium/genética , ARN Viral/genética , Adolescente , Niño , Preescolar , Coinfección , Estudios Transversales , Dengue/virología , Virus del Dengue/clasificación , Virus del Dengue/aislamiento & purificación , Femenino , Ghana/epidemiología , Humanos , Lactante , Recién Nacido , Malaria/parasitología , Masculino , Plasmodium/clasificación , Plasmodium/aislamiento & purificación , Reacción en Cadena en Tiempo Real de la Polimerasa , SerogrupoRESUMEN
BACKGROUND: Complete and accurate information on disease occurrence is crucial for effective public health response to disease outbreaks. In response to the 2014 Ebola epidemic in West Africa, Ghana intensified surveillance for the disease across the country. However, the case definition provided by the Ministry of Health was not uniformly applied at all reporting health facilities. OBJECTIVE: This paper analyses the accompanying Case Record Forms (CRFs) submitted to Noguchi Memorial Institute for Medical Research to determine its completeness and appropriateness for instituting an effective response to the epidemic. METHODS: We determined the proportions of completeness in reporting for all criteria provided by the MOH for the clinical diagnosis of Ebola. New indicators were generated to measure the completeness of each variable. Tables and graphs of completeness of indicators were produced and presented. RESULTS: Of the 156 samples, 69% were from males. Approximately 4.5% had no record for age. The date of specimen collection was filled for 96%; 34.6% (54) did not have date of onset of symptoms. In 37.8% (59) of cases, location was blank. In 12% of cases, no symptoms were recorded and about 30% had no record of fever. Travel history, especially to affected areas, was missing for 40.4%. CONCLUSIONS: Gaps on CRFs can significantly reduce the utility of results of laboratory analysis for outbreak control. Although all the samples analysed were negative for Ebola Virus, the high proportion of missing data on the forms should be a source of concern. We recommend that frontline health staff be trained on the importance of capturing all information required on the form. SOURCE OF FUNDING: The funding for the analysis of suspected samples were provided partially by Ghana Health Servce and research funding from Noguchi Memorial Institute for Medical Research.
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Fiebre Hemorrágica Ebola/epidemiología , Vigilancia en Salud Pública/métodos , Adolescente , Adulto , Exactitud de los Datos , Brotes de Enfermedades/prevención & control , Femenino , Ghana , Fiebre Hemorrágica Ebola/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Viaje , Adulto JovenRESUMEN
BACKGROUND: Recent reports have shown an expansion of Lassa virus from the area where it was first isolated in Nigeria to other areas of West Africa. Two Ghanaian soldiers on a United Nations peacekeeping mission in Liberia were taken ill with viral haemorrhagic fever syndrome following the death of a sick colleague and were referred to a military hospital in Accra, Ghana, in May 2013. Blood samples from the soldiers and five asymptomatic close contacts were subjected to laboratory investigations. OBJECTIVE: We report the results of these investigations to highlight the importance of molecular diagnostic applications and the need for heightened awareness about Lassa fever in West Africa. METHODS: We used molecular assays on sera from the two patients to identify the causative organism. Upon detection of positive signals for Lassa virus ribonucleic material by two different polymerase chain reaction assays, sequencing and phylogenetic analyses were performed. RESULTS: The presence of Lassa virus in the soldiers' blood samples was shown by L-gene segment homology to be the Macenta and las803792 strains previously isolated in Liberia, with close relationships then confirmed by phylogenetic tree construction. The five asymptomatic close contacts were negative for Lassa virus. CONCLUSIONS: The Lassa virus strains identified in the two Ghanaian soldiers had molecular epidemiological links to strains from Liberia. Lassa virus was probably responsible for the outbreak of viral haemorrhagic fever in the military camp. These data confirm Lassa fever endemicity in West Africa.
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Background: Recent reports have shown an expansion of Lassa virus from the area where it was first isolated in Nigeria to other areas of West Africa. Two Ghanaian soldiers on a United Nations peacekeeping mission in Liberia were taken ill with viral haemorrhagic fever syndrome following the death of a sick colleague and were referred to a military hospital in Accra; Ghana; in May 2013. Blood samples from the soldiers and five asymptomatic close contacts were subjected to laboratory investigations.Objective: We report the results of these investigations to highlight the importance of molecular diagnostic applications and the need for heightened awareness about Lassa fever in West Africa.Methods: We used molecular assays on sera from the two patients to identify the causativeorganism. Upon detection of positive signals for Lassa virus ribonucleic material by two different polymerase chain reaction assays; sequencing and phylogenetic analyses were performed.Results: The presence of Lassa virus in the soldiers' blood samples was shown by L-gene segment homology to be the Macenta and las803792 strains previously isolated in Liberia; with close relationships then confirmed by phylogenetic tree construction. The five asymptomatic close contacts were negative for Lassa virus.Conclusions: The Lassa virus strains identified in the two Ghanaian soldiers had molecular epidemiological links to strains from Liberia. Lassa virus was probably responsible for the outbreak of viral haemorrhagic fever in the military camp. These data confirm Lassa fever endemicity in West Africa
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Ghana , Hospitales Militares , Fiebre de Lassa , Reacción en Cadena de la PolimerasaRESUMEN
BACKGROUND: Lassa fever is a potentially fatal acute viral illness caused by Lassa virus which is carried by rodents and is endemic in some West African countries. Importation of emerging infections such as Lassa fever, Ebola Virus Disease and other viral hemorrhagic fevers into non endemic regions is a growing threat particularly as international travel and commitments in resolving conflicts in endemic countries in the West Africa sub-region continue. CASE PRESENTATION: We report the first two recorded imported cases of Lassa fever among Ghanaian Peace keepers in rural Liberia, who became ill while on Peace keeping mission. They were subsequently evacuated to the UN level IV hospital in Accra, where their illnesses were laboratory confirmed. One of the patients recovered with ribavirin treatment and supportive therapy. No secondary clinical cases occurred in Ghana. CONCLUSIONS: Healthcare providers at all levels of care should thus have a high index of suspicion for these infectious diseases and adopt standard infection control measures when treating patients in endemic regions or returning travelers from an endemic region with a febrile illness even of a known etiology.
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Antivirales/uso terapéutico , Trazado de Contacto , Fiebre de Lassa/tratamiento farmacológico , Personal Militar , Ribavirina/uso terapéutico , Viaje , Adulto , Enfermedades Transmisibles Emergentes , Ghana , Humanos , Fiebre de Lassa/diagnóstico , Fiebre de Lassa/transmisión , Virus Lassa/genética , Liberia , Masculino , Salud PúblicaRESUMEN
BACKGROUND: Influenza A viruses that cause highly pathogenic avian influenza (HPAI) also infect humans. In many developing countries such as Ghana, poultry and humans live in close proximity in both the general and military populations, increasing risk for the spread of HPAI from birds to humans. Respiratory infections such as influenza are especially prone to rapid spread among military populations living in close quarters such as barracks making this a key population for targeted avian influenza surveillance and public health education. METHOD: Twelve military barracks situated in the coastal, tropical rain forest and northern savannah belts of the country were visited and the troops and their families educated on pandemic avian influenza. Attendants at each site was obtained from the attendance sheet provided for registration. The seminars focused on zoonotic diseases, influenza surveillance, pathogenesis of avian influenza, prevention of emerging infections and biosecurity. To help direct public health policies, a questionnaire was used to collect information on animal populations and handling practices from 102 households in the military barracks. Cloacal and tracheal samples were taken from 680 domestic and domesticated wild birds and analysed for influenza A using molecular methods for virus detection. RESULTS: Of the 1028 participants that took part in the seminars, 668 (65%) showed good knowledge of pandemic avian influenza and the risks associated with its infection. Even though no evidence of the presence of avian influenza (AI) infection was found in the 680 domestic and wild birds sampled, biosecurity in the households surveyed was very poor. CONCLUSION: Active surveillance revealed that there was no AI circulation in the military barracks in April 2011. Though participants demonstrated good knowledge of pandemic avian influenza, biosecurity practices were minimal. Sustained educational programs are needed to further strengthen avian influenza surveillance and prevention in military barracks.
Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Virus de la Influenza A , Gripe Aviar/prevención & control , Gripe Humana/epidemiología , Instalaciones Militares , Personal Militar/educación , Animales , Aves , Estudios Transversales , Femenino , Ghana/epidemiología , Humanos , Virus de la Influenza A/aislamiento & purificación , Gripe Aviar/epidemiología , Gripe Humana/prevención & control , Masculino , Personal Militar/psicología , Aceptación de la Atención de Salud/estadística & datos numéricos , Vigilancia de la Población , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Sensibilidad y EspecificidadRESUMEN
BACKGROUND: The global annual attack rate for influenza is estimated to be 10%-20% in children, although limited information exists for Africa. In 2007, Ghana initiated influenza surveillance by routine monitoring of acute respiratory illness to obtain data on circulating strains. We describe influenza surveillance in children <11 years old who had influenza-like illness (ILI) from January 2008 to December 2010. METHODS: Oropharyngeal swabs from pediatric outpatients with ILI attending any of 22 health facilities across the country were submitted. We tested swabs for influenza virus using molecular assays, virus isolation, and hemagglutination assays. RESULTS: Of the 2810 swabs, 636 (23%) were positive for influenza virus. The percentage of positives by gender was similar. The proportion of ILI cases positive for influenza increased with age from 11% (31/275) in infants (aged 0-1 years) to 31% (377/1219) among children aged 5-10 years (P < .001). The majority of cases were influenza A (90%), of which 60% were influenza A(H1N1)pdm09. In all 3 years, influenza activity appeared slightly higher during May through July. CONCLUSIONS: During the 3 years of influenza surveillance in Ghana, children aged <11 years bore a high burden of influenza-associated ILI.