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Rhizospheric microbial communities improve the effectiveness of hyperaccumulators in the phytoremediation of heavy metals. However, limited access to tailing dams and inadequate assessment of plants' phytoremediation potential limit the characterization of native accumulators, hindering the effectiveness of local remediation efforts. This study evaluates the heavy metal sequestration potentials of Pennisetum purpureum, Leucaena leucocephala, and Pteris vittata and their associated rhizospheric microbial communities at the Marlu and Pompora tailing dams in Ghana. The results indicate shoot hyperaccumulation of Cd (334.5 ± 6.3 mg/kg) and Fe (10,647.0 ± 12.6 mg/kg) in P. purpureum and L. leucocephala, respectively. Analysis of rhizospheric bacterial communities revealed the impact of heavy metal contamination on bacterial community composition, associating Fe and Cd hyperaccumulation with Bacillus, Arthrobacter, and Sphingomonas species. This study reports the hyperaccumulation potentials of L. leucocephala and P. purpureum enhanced by associated rhizosphere bacterial communities, suggesting their potential application as an environmentally friendly remediation process of heavy metals contaminated lands.
The novelty of this study is the report of the heavy metal accumulation potentials of the fast-growing herbaceous plants Leucaena leucocephala and Pennisetum purpureum at abandoned gold mine tailing dams in Ghana. Substantial amounts of Cd (334.5 mg/kg) and Fe (10,647.0 mg/kg) were accumulated in P. purpureum and L. leucocephala shoots, indicating their hyperaccumulation potentials. The concentration of heavy metal levels in the rhizosphere influenced the bacterial community structure, with the abundance of Bacillus, Arthrobacter, and Sphingomonas linked to hyperaccumulation. The outcome of this study supports the utilization of L. leucocephala and P. purpureum in the phytoremediation of lands contaminated with heavy metals.
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Biodegradação Ambiental , Metais Pesados , Microbiota , Mineração , Rizosfera , Poluentes do Solo , Poluentes do Solo/metabolismo , Metais Pesados/metabolismo , Gana , Microbiologia do Solo , Pennisetum/metabolismo , Fabaceae , Bactérias/metabolismoRESUMO
BACKGROUND: Encephalitis is a serious disease of the brain characterized by prodromal and specific neurological symptoms. HIV infections offer opportunistic viruses, such as Varicella-zoster virus (VZV), the chance to cause encephalitis in patients. There is a lack of information on the genetic diversity of VZV in Ghana and other parts of Africa which requires sequencing and characterization studies to address. The active evolution of HIV-1 in West Africa also requires continuous surveillance for the emergence of new genetic forms. CASE PRESENTATION: VZV was detected in the CSF sample of an 11-year-old patient presenting with symptoms of encephalitis by real-time PCR diagnostics. To identify possible unknown aetiological pathogens, next-generation sequencing was performed, and revealed an HIV-1 co-infection. Alignments of concatenated HIV-1 genome fragments in the gag, pol, vif, env and nef regions and a near-complete VZV genome were analyzed by Bayesian inference, and phylogenetic trees were generated. The VZV sequence belongs to clade 5 and the HIV-1 sequence is a member of the CRF02_AG predominant circulating recombinant form in Ghana. CONCLUSIONS: Diagnostic tests for CSF HIV would be useful where possible in patients presenting with encephalitis due to VZV and other opportunistic viruses in Kumasi to shed light on the role of HIV in encephalitis cases in Ghana. This report reaffirms the role of the CRF02_AG circulating recombinant form in HIV infections in Ghana and also gives a preliminary genetic characterization of VZV in Kumasi, Ghana.
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Varicela , Coinfecção , Encefalite , Infecções por HIV , HIV-1 , Herpes Zoster , Teorema de Bayes , Criança , Gana , HIV-1/genética , Herpes Zoster/diagnóstico , Herpesvirus Humano 3/genética , Humanos , FilogeniaRESUMO
Following the detection of the first imported case of COVID-19 in the northern sector of Ghana, we molecularly characterized and phylogenetically analysed sequences, including three complete genome sequences, of severe acute respiratory syndrome coronavirus 2 obtained from nine patients in Ghana. We performed high-throughput sequencing on nine samples that were found to have a high concentration of viral RNA. We also assessed the potential impact that long-distance transport of samples to testing centres may have on sequencing results. Here, two samples that were similar in terms of viral RNA concentration but were transported from sites that are over 400 km apart were analyzed. All sequences were compared to previous sequences from Ghana and representative sequences from regions where our patients had previously travelled. Three complete genome sequences and another nearly complete genome sequence with 95.6% coverage were obtained. Sequences with coverage in excess of 80% were found to belong to three lineages, namely A, B.1 and B.2. Our sequences clustered in two different clades, with the majority falling within a clade composed of sequences from sub-Saharan Africa. Less RNA fragmentation was seen in sample KATH23, which was collected 9 km from the testing site, than in sample TTH6, which was collected and transported over a distance of 400 km to the testing site. The clustering of several sequences from sub-Saharan Africa suggests regional circulation of the viruses in the subregion. Importantly, there may be a need to decentralize testing sites and build more capacity across Africa to boost the sequencing output of the subregion.
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COVID-19/transmissão , SARS-CoV-2/classificação , Sequenciamento Completo do Genoma/métodos , Feminino , Genoma Viral , Gana , Humanos , Masculino , Nasofaringe/virologia , Orofaringe/virologia , Filogenia , SARS-CoV-2/genética , Análise de Sequência de RNARESUMO
Objective: This study aimed to investigate the impact of diabetes mellitus (DM) on tuberculosis (TB) treatment response using bacterial clearance as a surrogate marker. Method: We compared smear microscopy, culture, and tuberculosis molecular bacterial load assay (TB-MBLA) for treatment monitoring. Following that, bacterial clearance was longitudinally monitored among TB-only (TB without DM) and TB-diabetes (TBDM) patients using TB-MBLA. Results: Ninety-three participants, including 59 TB-only and 34 TBDM patients, were enrolled. TB-only patients exhibited higher upper zone infiltrations (32/35 vs 16/22, p = 0.059) suggesting a trend towards significance, and significantly more cavitation in the same zone (16/18 vs 7/13, p = 0.028). There was a high proportion of Mycobacterium africanum (Maf) among the TBDM cohort (p = 0.0044).At baseline, TB-only patients exhibited a higher average bacterial burden (4.49 logeCFU/mL) compared to the TBDM group (3.91 logeCFU/mL) (p = 0.042). The bacterial load in the TB-only group decreased significantly during treatment but the TBDM group experienced delayed clearance throughout the intensive phase of anti-TB treatment even at day 56 (p = 0.028). The TB-only group demonstrated a shorter median time to TB-MBLA conversion to negative (57 days) compared to the TBDM group (62 days) (p = 0.022). Conclusion: These findings underscore the urgent call for understanding the interplay between diabetes and TB, emphasizing the need for tailored interventions in optimizing TB care for individuals comorbid with diabetes.
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Pneumonia is the leading cause of death in children, however, the microbial aetiology of pneumonia is not well elucidated in low- and middle-income countries. Our study was aimed at determining the microbial aetiologies of childhood pneumonia and associated risk factors in HIV and non-HIV infected children. We conducted a case-control study that enrolled children with pneumonia as cases and non-pneumonia as controls from July 2017 to May 2020. Induced sputum and blood samples were investigated for microbial organisms using standard microbiological techniques. DNA/RNA was extracted from sputum samples and tested for viral and bacterial agents. Four hundred and four (404) subjects consisting of 231 (57.2%) cases and 173 (42.8%) controls were enrolled. We identified a significant (p = 0.011) proportion of viruses in cases (125; 54.1%, 95%CI: 47.4-60.7) than controls (71; 33.6%, 95%CI: 33.6-48.8) and these were mostly contributed to by Respiratory Syncytial Virus. Staphylococcus aureus (16; 4.0%), Klebsiella spp. (15, 3.7%) and Streptococcus pneumoniae (8, 2.0%) were the main bacterial agents identified in sputum or induced sputum samples. HIV infected children with viral-bacterial co-detection were found to have very severe pneumonia compared to those with only viral or bacterial infection. Indoor cooking (OR = 2.36; 95%CI:1.41-3.96) was found to be associated with pneumonia risk in patients. This study demonstrates the importance of various microbial pathogens, particularly RSV, in contributing to pneumonia in HIV and non-HIV paediatric populations. There is a need to accelerate clinical trials of RSV vaccines in African populations to support improvement of patient care.
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Infecções por HIV , Pneumonia , Infecções Estafilocócicas , Criança , Humanos , Lactente , Estudos de Casos e Controles , Gana/epidemiologia , Pneumonia/epidemiologia , Pneumonia/etiologia , Infecções Estafilocócicas/complicações , Infecções por HIV/complicações , Infecções por HIV/epidemiologiaRESUMO
Viral encephalitis is a rare, yet severe neurological disorder. It poses a significant public health threat due to its high morbidity and mortality. Despite the disproportionate burden of the disease in impoverished African countries, the true extent of the problem remains elusive due to the scarcity of accurate diagnostic methods. The absence of timely and effective diagnostic tools, particularly Real-time Polymerase Chain Reaction, has led to misguided treatment, and an underestimation of the disease burden in Ghana. We conducted a prospective cross-sectional study to determine the viral aetiologies of encephalitis among patients presenting to a major referral hospital in Ghana from May 2019 and August 2022. The study aimed at providing a comprehensive information on the clinical epidemiology, and outcomes of viral encephalitis in Ghana. Clinical samples were collected from patients presenting with signs and symptoms of encephalitis and tested for viral agents using real-time polymerase chain reaction. We assessed the clinical epidemiology, risk factors and outcome of individuals using descriptive and logistic regression analysis. Seventy-seven (77) patients were enrolled unto the study. The participants frequently presented with fever (85.7%), seizures (80.5%), lethargy (64.9%) and headache (50.6%). Viruses were detected in 40.3% of the study participants in either cerebrospinal fluid, rectal or oral swab samples. The most frequently detected viruses were cytomegalovirus (48.4%), enteroviruses (38.7%) and HSV (29.0%). Twenty-one (27.3%) of the patients died while on hospital admission. Gender (OR = 5.70 (1.536-1.172), p = 0.01), and negative polymerase chain reaction test results were identified as significant factors associated with death. Antiviral treatment increased the chance of survival of viral encephalitis patients by 21.8%. Our results validate the crucial role of molecular tools as essential for the rapid diagnosis of viral encephalitis, enabling effective treatment and improved patient outcomes. This study contributes valuable epidemiological and clinical insight into viral encephalitis in Ghana.
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Encefalite Viral , Vírus , Humanos , Estudos Transversais , Gana/epidemiologia , Estudos Prospectivos , Encefalite Viral/diagnóstico , Encefalite Viral/epidemiologia , Reação em Cadeia da Polimerase em Tempo RealRESUMO
BACKGROUND: Treponema pallidum (TP) is a spirochaete bacterium with subspecies that in humans cause syphilis (subsp. pallidum), bejel (subsp. endemicum) and yaws (subsp. pertenue; TPE). The latter is target for eradication which requires detailed information on yaws epidemiology. It has been shown that African nonhuman primates (NHPs) are infected with TPE strains that are closely related to the human infecting yaws bacterium. While human yaws infection is known to be endemic in Ghana, there is a paucity of information regarding TPE infection of Ghana's native NHPs. OBJECTIVES: The objective was to perform a small-scale cross-sectional serological screening for antibodies against TPE in Ghanaian monkeys. Due to the reports of TPE-infected NHPs from neighbouring Côte d'Ivore, we hypothesised that monkeys in Ghana are infected with TPE and, therefore, are seropositive for antibodies against-Treponema. METHODS: We sampled blood from 37 NHPs representing four species: Erythrocebus patas (16/37) 43.2%, Papio anubis (15/37) 40.5%, Chlorocebus sabaeus (3/37) 8.1% and Cercopithecus mona (3/37) 8.1%. Samples were tested using the NHP validated treponemal test ESPLINE TP. RESULTS: All 37 animals were seronegative for yaws infection. CONCLUSIONS: We cannot exclude yaws infection in NHPs in Ghana at this point. Our study, in combination with the absence of reports of clinically infected NHPs in a yaws endemic country is, however, supportive for the current thinking that interspecies infection with TPE is extremely rare. This is an important finding for the current ongoing yaws eradication campaign.
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Bouba , Humanos , Chlorocebus aethiops , Animais , Bouba/epidemiologia , Bouba/veterinária , Bouba/microbiologia , Gana/epidemiologia , Haplorrinos , Estudos Transversais , Treponema pallidum , Papio anubis , CercopithecusRESUMO
BACKGROUND: The potential for the transfer of zoonotic diseases, including bacteria between human and non-human primates (NHPs), is expected to rise. It is posited that NHPs that live in close contact with humans serve as sentinels and reservoirs for antibiotic-resistant bacteria. OBJECTIVES: The objective was to characterize the oral and rectal bacteria in Ghanaian NHPs and profile the antimicrobial susceptibility of the isolated bacteria. METHODS: Oral and rectal swabs were obtained from 40 immobilized wild and captive NHPs from 7 locations in Ghana. Standard bacteriological procedures were used in the isolation, preliminary identification, automated characterization and antimicrobial susceptibility test (AST) of bacteria using the Vitek 2 Compact system. RESULTS: Gram-negative bacteria dominated isolates from the rectal swabs (n = 76, 85.4%), whereas Gram-positive bacteria were more common in the oral swabs (n = 41, 82%). Staphylococcus haemolyticus (n = 7, 14%) was the most occurring bacterial species isolated from the oral swabs, whereas Escherichia coli (n = 32, 36%) dominated bacteria isolates from rectal swabs. Enterobacter spp. had the highest (39%) average phenotypic resistance to antimicrobials that were used for AST, whereas a trend of high resistance was recorded against norfloxacin, Ampicillin and Tetracycline in Gram-negative bacteria. Similarly, among Gram-positive bacteria, Staphylococcus spp. had the highest (25%) average phenotypic resistance to antimicrobials used for AST, and a trend of high resistance was recorded against penicillin G and oxacillin. CONCLUSIONS: This study has established that apparently healthy NHPs that live in anthropized environments in Ghana harbour zoonotic and antimicrobial resistant bacteria.
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In low-resource settings with high tuberculosis (TB) burdens, lack of rapid diagnostic methods for detection and differentiation of Mycobacterium tuberculosis complex (MTBC) is a major challenge affecting TB management. This study utilized comparative genomic analyses of MTBC lineages; M. tuberculosis, M. africanum Lineages 5/6 and M. bovis to identify lineage-specific genes. Primers were designed for the development of a Multiplex PCR assay which was successful in differentiating the MTBC lineages. There was no cross-reaction with other respiratory pathogens tested. Validation of the assay using clinical samples was performed with sputum DNA extracts from 341 clinically confirmed active TB patients. It was observed that 24.9% of cases were caused by M. tuberculosis, while M. africanum L5 & L6 reported 9.0% and 14.4%, respectively. M. bovis infection was the least frequently detected lineage with 1.8%. Also, 27.0% and 17.0% of the cases were PCR negative and unspeciated, respectively. However, mixed-lineage TB infections were recorded at a surprising 5.9%. This multiplex PCR assay will allow speciation of MTBC lineages in low-resource regions, providing rapid differentiation of TB infections to select appropriate medication at the earliest possible time point. It will also be useful in epidemiological surveillance studies providing reliable information on the prevalence of TB lineages as well as identifying difficult to treat cases of mixed-lineage tuberculosis infections.
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Tuberculose Latente , Mycobacterium tuberculosis , Tuberculose , Humanos , Mycobacterium tuberculosis/genética , Reação em Cadeia da Polimerase Multiplex/métodos , Gana/epidemiologia , Tuberculose/diagnóstico , Tuberculose/epidemiologia , Tuberculose/microbiologiaRESUMO
BACKGROUND: The use of motor tricycles in transporting municipal solid waste (MSW) within urban and peri-urban towns in Ghana is on the increase. This activity often leads to the introduction of pathogen-containing bioaerosols into the environment, as well as to the tricycle operators. We sought to investigate the prevalence and associated risk factors of respiratory pathogens among solid waste tricycle operators. METHODS: A cross-sectional study was conducted among 155 solid waste transporters who use motor tricycles using semi-structured interviews. Nasopharyngeal swabs were obtained from participants and screened for respiratory pathogens using Polymerase Chain Reaction (PCR). RESULTS: Pathogens detected in participants were SARS-CoV-2 (n = 10, 6.5%) and Streptococcus pneumoniae (n = 10, 6.5%), constituting an overall prevalence of 12.9% and co-infection rate of 1.3%. The most common self-reported symptoms were cough (n = 67, 43.2%), sore throat (n = 44, 28.4%) and difficulty in breathing (n = 22, 14.2%). Adherence to the use of gloves (n = 117, 75.5%) and nose mask (n = 110, 71.0%) was high. There was a significant association between the detection of respiratory pathogens and the use of gloves, use of more than one PPE and exposure to other pollutants (p < 0.05). Individuals who were exposed to "other pollutants" significantly had lower odds of becoming infected with respiratory pathogens (Adj. OR (95% CI): 0.119(0.015,0.938). CONCLUSION: Although prevalence of respiratory pathogens is generally low, strict adherence to PPE use could further reduce its rates to even lower levels. Governmental health institutions and informal solid waste transporters should address challenges related to exposure to pollutants, use of gloves, and multiple PPE.
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COVID-19 , Resíduos Sólidos , Humanos , SARS-CoV-2 , Gana , Estudos Transversais , AutorrelatoRESUMO
Since the global pandemic of the 2019 coronavirus disease (COVID-19), few studies have reported on the relevance of bacteria co-infection on outcome of COVID-19 patients. Little is known about the clinical presentation among pregnant women, mother-to-child transmission, and fetal outcomes. This report shows a 24-year-old nulliparous woman who was 32 weeks pregnant and was admitted to the University Hospital, Kwame Nkrumah University of Science and Technology (KNUST), Kumasi Ghana with symptoms of fever (40.3°C), cough and breathlessness of two weeks duration. Her nasopharyngeal sample tested positive for Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) and blood culture isolated Burkholderia cepacia. She was given medications but went into pre-term labour and delivered a stillborn baby. This rare case of COVID-19 and Burkholderia cepacia co-infection emphasizes the need for a thorough assessment and appropriate treatment of patients presenting with fever and respiratory symptoms in order to mitigate poor outcome.
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Burkholderia cepacia , COVID-19 , Coinfecção , Complicações Infecciosas na Gravidez , Adulto , COVID-19/complicações , COVID-19/diagnóstico , Coinfecção/diagnóstico , Feminino , Morte Fetal , Febre/etiologia , Humanos , Transmissão Vertical de Doenças Infecciosas , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico , Resultado da Gravidez , SARS-CoV-2 , Adulto JovemRESUMO
Every child has the right to survive, grow and develop. However, in spite of the considerable global gains that have been made in child survival, Sub-Saharan Africa still has the highest child mortality rates and accounts for the greatest burden of mortality globally. The majority of these children die without ever reaching a health facility. The practice of appropriate healthcare-seeking behaviour has a great potential to reduce the occurrence of severe and life-threatening childhood illnesses. Several factors, however, influence healthcare-seeking behaviour, including perceptions of the cause of illness and socio-cultural perspectives. This study seeks to understand local concepts of a traditionally-defined illness complex, Asram, and its influence on healthcare seeking behavior of mothers/caregivers. This qualitative study was conducted from October 2019 to February 2020. Four Focus Group Discussions were conducted with mothers/caregivers of children under-5 and 22 Key Informant Interviews with mothers/caregivers of children who had Asram, health workers at district, facility, and community levels, and Asram healers. Participants were selected from two rural communities, Akutuase and Wioso of the Asante Akim North district in the Ashanti region of Ghana. Data analysis was carried out iteratively throughout data collection, using a thematic analysis approach. The study shows that Asram is a childhood illness complex that is perceived to have been acquired spiritually and/or inherited. Nine types of Asram were described. This childhood illness was said to be treatable by Asram healers who had sub-specialties in treatment approaches that were determined by the Asram type reported. Mothers/caregivers trusted Asram healers and preferred to call on them first. This was found to be the main reason for delays in seeking healthcare for children under-5 who showed symptoms of Asram. Asram is a childhood illness complex that is believed to be better managed outside the health facility setting. This study complements existing knowledge and creates opportunities for further research and the introduction of more effective interventions in the effort to improve child survival in rural communities.
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The novel coronavirus disease 2019 (COVID-19) is one of the biggest public health crises globally. Although Africa did not display the worst-case scenario compared to other continents, fears were still at its peak since Africa was already suffering from a heavy load of other life-threatening infectious diseases such as HIV/AIDS and malaria. Other factors that were anticipated to complicate Africa's outcomes include the lack of resources for diagnosis and contact tracing along with the low capacity of specialized management facilities per capita. The current review aims at assessing and generating discussions on the realities, and pros and cons of the WHO COVID-19 interim guidance 2020.5 considering the known peculiarities of the African continent. A comprehensive evaluation was done for COVID-19-related data published across PubMed and Google Scholar (date of the last search: August 17, 2020) with emphasis on clinical management and psychosocial aspects. Predefined filters were then applied in data screening as detailed in the methods. Specifically, we interrogated the WHO 2020.5 guideline viz-a-viz health priority and health financing in Africa, COVID-19 case contact tracing and risk assessment, clinical management of COVID-19 cases as well as strategies for tackling stigmatization and psychosocial challenges encountered by COVID-19 survivors. The outcomes of this work provide links between these vital sub-themes which may impact the containment and management of COVID-19 cases in Africa in the long-term. The chief recommendation of the current study is the necessity of prudent filtration of the global findings along with regional modelling of the global care guidelines for acting properly in response to this health threat on the regional level without exposing our populations to further unnecessary adversities.
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BACKGROUND: The declaration of COVID-19 as a pandemic on March 11 2020, by the World Health Organisation prompted the need for a sustained and a rapid international response. In a swift response, the Government of Ghana, in partnership with Zipline company, launched the use of Unmanned Automated Vehicles (UAV) to transport suspected samples from selected districts to two foremost testing centres in the country. Here, we present the experiences of employing this technology and its impact on the transport time to the second largest testing centre, the Kumasi Centre for Collaborative Research in Tropical Medicine (KCCR) in Kumasi, Ghana. METHODS: Swab samples collected from suspected COVID-19 patients were transported to the Zipline office by health workers. Information on the samples were sent to laboratory personnel located at KCCR through a WhatsApp platform to get them ready to receive the suspected COVID-19 samples while Zipline repackaged samples and transported them via drone. Time of take-off was reported as well as time of drop-off. RESULTS: A total of 2537 COVID-19 suspected samples were received via drone transport from 10 districts between April 2020 to June 2021 in 440 deliveries. Ejura-Sekyedumase District Health Directorate delivered the highest number of samples (765; 30%). The farthest district to use the drone was Pru East, located 270 km away from KCCR in Kumasi and 173 km to the Zipline office in Mampong. Here, significantly, it took on the average 39 minutes for drones to deliver samples compared to 117 minutes spent in transporting samples by road (p<0.001). CONCLUSION: The use of drones for sample transport during the COVID-19 pandemic significantly reduced the travel time taken for samples to be transported by road to the testing site. This has enhanced innovative measures to fight the pandemic using technology.
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COVID-19 , Dispositivos Aéreos não Tripulados , Humanos , Gana , PandemiasRESUMO
Real-world data on vaccine-elicited neutralising antibody responses for two-dose AZD1222 in African populations are limited. We assessed baseline SARS-CoV-2 seroprevalence and levels of protective neutralizing antibodies prior to vaccination rollout using binding antibodies analysis coupled with pseudotyped virus neutralisation assays in two cohorts from West Africa: Nigerian healthcare workers (n = 140) and a Ghanaian community cohort (n = 527) pre and post vaccination. We found 44 and 28% of pre-vaccination participants showed IgG anti-N positivity, increasing to 59 and 39% respectively with anti-receptor binding domain (RBD) IgG-specific antibodies. Previous IgG anti-N positivity significantly increased post two-dose neutralizing antibody titres in both populations. Serological evidence of breakthrough infection was observed in 8/49 (16%). Neutralising antibodies were observed to wane in both populations, especially in anti-N negative participants with an observed waning rate of 20% highlighting the need for a combination of additional markers to characterise previous infection. We conclude that AZD1222 is immunogenic in two independent West African cohorts with high background seroprevalence and incidence of breakthrough infection in 2021. Waning titres post second dose indicates the need for booster dosing after AZD1222 in the African setting despite hybrid immunity from previous infection.
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COVID-19 , Vacinas Virais , Anticorpos Neutralizantes , Anticorpos Antivirais , Formação de Anticorpos , COVID-19/epidemiologia , COVID-19/prevenção & controle , ChAdOx1 nCoV-19 , Gana , Humanos , Imunoglobulina G , SARS-CoV-2 , Estudos Soroepidemiológicos , VacinaçãoRESUMO
INTRODUCTION: acute respiratory tract infections (ARIs) are responsible for significant proportions of illnesses and deaths annually. Most of ARIs are of viral etiology, with human coronaviruses (HCoVs) playing a key role. This study was conducted prior to the outbreak of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) to provide evidence about the sero-epidemiology of HCoVs in rural areas of Ghana. METHODS: this was a cross-sectional study conducted as part of a large epidemiological study investigating the occurrence of respiratory viruses in 3 rural areas of Ghana; Buoyem, Kwamang and Forikrom. Serum samples were collected and tested for the presence of IgG-antibodies to three HCoVs; HCoV-229E, HCoV-OC43 and HCoV-NL63 using immunofluorescence assay. RESULTS: of 201 subjects enrolled into the study, 97 (48.3%) were positive for all three viruses. The most prevalent virus was HCoV-229E (23%; 95% CI: 17.2 - 29.3), followed by HCoV-OC43 (17%; 95% CI: 12.4 - 23.4), then HCoV-NL63 (8%, 95% CI: 4.6 - 12.6). Subjects in Kwamang had the highest sero-prevalence for HCoV-NL63 (68.8%). human coronaviruses-229E (41.3%) and HCoV-OC43 (45.7%) were much higher in Forikrom compared to the other study areas. There was however no statistical difference between place of origin and HCoVs positivity. Although blood group O+ and B+ were most common among the recruited subjects, there was no significant association (p = 0.163) between blood group and HCoV infection. CONCLUSION: this study reports a 48.3% sero-prevalence of HCoVs (OC43, NL63 and 229E) among rural communities in Ghana. The findings provide useful baseline data that could inform further sero-epidemiological studies on SARS-CoV-2 in Africa.
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Coronavirus Humano 229E/isolamento & purificação , Infecções por Coronavirus/epidemiologia , Coronavirus Humano NL63/isolamento & purificação , Coronavirus Humano OC43/isolamento & purificação , Adulto , Infecções por Coronavirus/virologia , Estudos Transversais , Feminino , Gana/epidemiologia , Humanos , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/virologia , População Rural/estatística & dados numéricos , Estudos Soroepidemiológicos , Adulto JovemRESUMO
Globally, resistance to antimicrobial drugs in food animals is on the rise. Escherichia coli of livestock, though commensal in nature, serves as reservoir for antimicrobial resistance genes with the potential of disseminating them. This study sought to examine the antimicrobial resistance profiles of Escherichia coli in broilers, pigs, and cattle in the Kumasi Metropolis and undertake molecular characterisation of the resistances. Faecal E. coli isolates (n = 48) were obtained from 10 broiler farms, (n = 43) from 15 pig farms, and (n = 42) from cattle from the Kumasi Abattoir using standard bacteriological techniques. The Kirby-Bauer disc diffusion method was employed in testing the sensitivities of 133 E. coli isolates to 15 antimicrobials. All 48 isolates from broilers presented no resistance to amoxicillin/clavulanic acid and ceftiofur. A 100% resistance to meropenem was observed in pig and cattle isolates. Multidrug resistance (MDR) across animal groups was 95.8% (n = 46), 95.3% (n = 41), and 64.3% (n = 27) for broilers, pigs, and cattle, respectively. Twenty-eight isolates presenting phenotypic resistance to aminopenicillins and cephalosporins were screened for the presence of extended-spectrum beta-lactamase (ESBL) genes by PCR. One isolate from poultry and another from cattle tested positive for the blaCTX-M ESBL gene. There were no positives for the blaTEM and blaSHV ESBL genes. Commensal E. coli of food animal origin represents an important reservoir of antimicrobial resistance that transfers resistance to pathogenic and nonpathogenic microbes affecting humans and animals. There is an urgent need to institute routine surveillance for the establishment of the mechanisms and molecular orientation of resistance in these organisms.
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The D614G variant of SARS-CoV-2 S-protein emerged in early 2020 and quickly became the dominant circulating strain in Europe and its environs. The variant was characterized by the higher viral load, which is not associated with disease severity, higher incorporation into the virion, and high cell entry via ACE-2 and TMPRSS2. Previous strains of the coronavirus and the current SARS-CoV-2 have demonstrated the selection of mutations as a mechanism of escaping immune responses. In this study, we used molecular dynamics simulation and MM-PBSA binding energy analysis to provide insights into the behaviour of the D614G S-protein at the molecular level and describe the neutralization mechanism of this variant. Our results show that the D614G S-protein adopts distinct conformational dynamics which is skewed towards the open-state conformation more than the closed-state conformation of the wild-type S-protein. Residue-specific variation of amino acid flexibility and domain-specific RMSD suggest that the mutation causes an allosteric conformational change in the RBD. Evaluation of the interaction energies between the S-protein and neutralizing antibodies show that the mutation may enhance, reduce or not affect the neutralizing interactions depending on the neutralizing antibody, especially if it targets the RBD. The results of this study have shed insights into the behaviour of the D614G S-protein at the molecular level and provided a glimpse of the neutralization mechanism of this variant.
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Enzima de Conversão de Angiotensina 2/química , Anticorpos Neutralizantes/química , Anticorpos Antivirais/química , Receptores Virais/química , SARS-CoV-2/genética , Serina Endopeptidases/química , Glicoproteína da Espícula de Coronavírus/química , Substituição de Aminoácidos , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/metabolismo , Anticorpos Neutralizantes/metabolismo , Anticorpos Antivirais/metabolismo , Sítios de Ligação , COVID-19/epidemiologia , COVID-19/imunologia , COVID-19/transmissão , COVID-19/virologia , Evolução Molecular , Regulação da Expressão Gênica , Interações Hospedeiro-Patógeno/genética , Humanos , Simulação de Dinâmica Molecular , Mutação , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Estrutura Secundária de Proteína , Receptores Virais/genética , Receptores Virais/metabolismo , SARS-CoV-2/imunologia , Seleção Genética , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , TermodinâmicaRESUMO
Coronavirus disease 2019 (COVID-19), a severe acute respiratory syndrome caused by SARS-CoV-2 was declared a global pandemic by the World Health Organization (WHO) in March 2020. As of 21st April 2021, the disease had affected more than 143 million people with more than 3 million deaths worldwide. Urgent effective strategies are required to control the scourge of the pandemic. Rapid sample collection and effective testing of appropriate specimens from patients meeting the suspect case definition for COVID-19 is a priority for clinical management and outbreak control. The WHO recommends that suspected cases be screened for SARS-CoV-2 virus with nucleic acid amplification tests such as real-time Reverse Transcription-Polymerase Chain Reaction (rRT-PCR). Other COVID-19 screening techniques such as serological and antigen tests have been developed and are currently being used for testing at ports of entry and for general surveillance of population exposure in some countries. However, there are limited testing options, equipment, and trained personnel in many African countries. Previously, positive patients have been screened more than twice to determine viral clearance prior to discharge after treatment. In a new policy directive, the WHO now recommends direct discharge after treatment of all positive cases without repeated testing. In this review, we discuss COVID-19 testing capacity, various diagnostic methods, test accuracy, as well as logistical challenges in Africa with respect to the WHO early discharge policy.
Assuntos
Teste para COVID-19/métodos , COVID-19/diagnóstico , Guias de Prática Clínica como Assunto , África , Humanos , Programas de Rastreamento/métodos , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Manejo de Espécimes , Organização Mundial da SaúdeRESUMO
INTRODUCTION: lower respiratory tract infections (LRTIs) are infections involving the trachea, primary bronchi and lungs. People with LRTIs typically experience coughs as the primary symptoms; however, shortness of breath, weakness, fever and fatigue may be coupled with the cough. It is common among the aged, children under five and the immune-suppressed. Persons with symptoms suggestive of pulmonary tuberculosis (TB) may have tuberculosis, other respiratory tract infection or co-infection of tuberculosis and other respiratory pathogens. This study aimed to identify the presence of pathogens in sputum of suspected tuberculosis cases and their antimicrobial resistance patterns. METHODS: this was a retrospective study conducted from September 2018 to November 2019 at Tamale Public Health Laboratory. Sputum or gastric lavage samples were collected from persons with suspected clinical presentations of TB and/or LRTI. These samples were cultured using standard microbiological protocols and antimicrobial susceptibility test performed on the positive cultures by Kirby-Bauer disc diffusion method. Molecular identification of M. tuberculosis was performed on all the suspected TB cases using GeneXpert mycobacterium tuberculosis/rifampin (MTB/RIF) assay. RESULTS: during the study period, there were 264 cases of which 49.2% were males and 50.8% were females. Positive cases for culture were 47.3%. Out of the 264 cases, 186 (70.5%) were suspected TB with 51.6% being positive for culture, 6.5% positive for M. tuberculosis (GeneXpert confirmed) and 3.8% co-infection of TB with other bacteria pathogens. Klebsiella spp. (35/125; 28%) and Pseudomonas spp. (19/125; 15.2%) were the most predominant pathogens isolated. There was no significant difference in detection of bacteria in males and females (p=0.89), however individuals with suspected TB were significantly infected with other bacterial species than the unsuspected individuals (p=0.03). Almost all the isolates showed high susceptibility towards carbapenem (meropenem) and high resistance towards the third generation cephalosporins (cefotaxime and ceftriaxone). CONCLUSION: this study highlights the need to test individuals with classical symptoms of LRTIs for other bacterial infections other than TB only. Sputum culture is recommended for all suspected tuberculosis cases to provide accurate laboratory diagnosis to LRTIs and mitigate unnecessary use of antimicrobials.