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BackgroundCOVID-19 disruptions including lockdowns and prioritization of COVID-19 control programs in Africa in 2020–2022 contributed to reductions in malaria control activities including malaria diagnosis, treatment and resistance monitoring. This study investigated the malaria burden and distribution on the background of active transmission of SARS-CoV-2 in Southern Ghana; utilizing community health education and medical screening (CHEMS) approach to determine epidemiological overlaps in COVID-19 and malaria.MethodsBetween October–December 2022, prospective cross-sectional surveys, with CHEMS were conducted in Greater Accra and Central regions, where 994 participants enrolled either at a hospital or community setting provided demographic and clinical data including history of clinical malaria infection and antimalarial treatment in the past 2 weeks. Of this study population, 953 provided nasal/throat swabs for COVID-19 RT-PCR testing, with a subset of 136 participants also providing finger-prick blood for malaria RDT testing.ResultsThe study population comprised of 73.6% adults, with 54.6% COVID-19 vaccination rate. Overall, 18.1% of participants had a history of clinical malaria, which was associated (adjusted odds ratio > 1.50, p-value ≤0.022) with COVID-19 symptoms and positivity, study area and hospital setting, suggestive of overlaps in the epidemiological risk for malaria. On a background of widespread SARS-CoV-2 infections (12–37%), malaria parasitaemia was detected in 6%, with 2% being co-infections with SARS-CoV-2. Among the malaria positives, 9.5% had a history of antimalarial treatment, which suggested that their infections were recrudescent parasitaemia.ConclusionThe epidemiological and clinical overlap between malaria and COVID-19 within the hospital and community settings underscores the need for accurate case diagnosis to inform effective clinical treatments. Innovative surveillance programs, with community engagement are needed to maximize control interventions including treatment of asymptomatic malaria infections.

Schistosomiasis is a neglected tropical disease that affects more than 200 million people and 45% of infections have been shown to occur in school-aged children. A large percentage of the disease burden lies in Africa. In 2012, the WHO outlined a roadmap for the elimination of schistosomiasis by 2020; however, this was not achieved. Treatment for schistosomiasis is by the use of Praziquantel, a drug in use for over 30 years and there is a concern for emerging drug resistance. There are several species of the genus Schistosoma causing infection in humans. For this study, Schistosoma mansoni which causes intestinal schistosomiasis will be investigated. There are reports of lowering cure rates and suboptimal response to praziquantel following several cycles of mass drug administration (MDA). Praziquantel resistance has also been reported in some countries and laboratory-bred schistosome experiments. To address the concerns of resistance, this study aims to employ a two-part approach to assess the prevalence of S. mansoni. praziquantel resistance amongst school-aged children in schistosomiasis endemic communities in Ghana and develop a diagnostic tool to aid in field assessment of infections. To achieve this, the study will attempt to answer the following research questions: 1. Is there developing S. mansoni praziquantel resistance in communities that have undergone several mass drug administrations? 2. Is there an interplay between intermediate host exposure to praziquantel and the development of praziquantel drug resistance in the definitive host?

Abstract Background Buruli ulcer (BU) disease, caused by Mycobacterium ulcerans (MU), and characterized by necrotic ulcers is still a health problem in Africa and Australia. The genome of the bacterium has several pseudogenes due to recent evolutionary events and environmental pressures. Pseudogenes are genetic elements regarded as nonessential in bacteria, however, they are less studied due to limited available tools to provide understanding of their evolution and roles in MU pathogenicity. Results This study developed a bioinformatic pipeline to profile the pseudogenomes of sequenced MU clinical isolates from different countries. One hundred and seventy-two MU genomes analyzed revealed that pseudogenomes of African strains corresponded to the two African lineages 1 and 2. Pseudogenomes were lineage and location specific and African lineage 1 was further divided into A and B. Lineage 2 had less relaxation in positive selection than lineage 1 which may signify different evolutionary points. Based on the Gil-Latorre model, African MU strains may be in the latter stages of evolutionary adaption and are adapting to an environment rich in metabolic resources with a lower temperature and decreased UV radiation. The environment fosters oxidative metabolism and MU may be less reliant on some secondary metabolites. In-house pseudogenomes from Ghana and Cote d’Ivoire were different from other African strains, however, they were identified as African strains. Conclusion Our bioinformatic pipeline provides pseudogenomic insights to complement other whole genome analyses, providing a better view of the evolution of the genome of MU and suggest an adaptation model which is important in understanding transmission. MU pseudogene profiles vary based on lineage and country, and an apparent reduction in insertion sequences used for the detection of MU which may adversely affect the sensitivity of diagnosis.

Urinary tract infections (UTIs) are frequent hospital-acquired infection, with Escherichia coli and Proteus mirabilis accounting for 90% of complicated UTIs. Emergence of multidrug-resistant (MDR) bacteria have complicated the treatment UTIs. P. mirabilis related UTIs has been associated with the production of urinary stones and long-term infections in patients with catheters. P. mirabilis and other uropathogens constitute a largely unexplored pathogen group. The pathogen is resistant to most antibiotics as a result of its impermeable outer membrane (OM). The β-barrel assemble machinery folds and inserts outer membrane proteins; however, there are no antibiotics targeting the OM assemble in clinical use currently. Therefore, this study seeks to identify drugs that will inhibit the activity of P. mirabilis B complex proteins and also determine their effects on P. mirabilis OM biogenesis. This would be achieved by screening approved drugs against the P. mirabilis Bam complex using computer-based in silico screening and cellular-based assays. First, the binding effects of drugs on P. mirabilis B complex proteins will be determined using docking algorithms. The antimicrobial and antivirulence activity of selected drugs from in silico analysis will be screened against MDR P. mirabilis. Finally, the effect of active drug(s) on the OM biogenesis of wild-type P. mirabilis and mutant P. mirabilis will be determined using peptide nucleic acids (PNA). Western lot analysis will be used to determine the abundance of proteins involved in OM biogenesis. Successful completion of this study will lead to the identification of novel antibiotics against MDR P. mirabilis and associated mechanisms while providing the foundation for future research endeavours on other uropathogens.

The burden of Hospital care-associated infections (HCAIs) is becoming a global concern. This is compounded by the emergence of virulent and high-risk bacterial strains such as “ESKAPE” pathogens – (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter species), especially within Intensive care units (ICUs) that house high-risk and immunocompromised patients. In this review, we discuss the contributions of AMR pathogens to the increasing burden of HCAIs and provide insights into AMR mechanisms, with a particular focus on last-resort antibiotics like polymyxins. We extensively discuss how structural modifications of surface-membrane lipopolysaccharides and cationic interactions influence and inform AMR, and subsequent severity of HCAIs. We highlight some bacterial phenotypic survival mechanisms against polymyxins. Lastly, we discuss the emergence of plasmid-mediated resistance as a phenomenon making mitigation of AMR difficult, especially within the ICUs. This review provides a balanced perspective on the burden of HCAIs, associated pathogens, implication of AMR and factors influencing emerging AMR mechanisms.

Mycobacterium ulcerans is the causative agent of Buruli ulcer – a necrotizing skin infection. As an environmental pathogen, it has developed stress response mechanisms for survival. Similar to endospore formation in M. marinum, it is likely that M. ulcerans employs sporulation mechanisms for its survival and transmission. In this review, we modeled possible transmission routes and patterns of M. ulcerans from the environment to its host. We provided insights into the evolution of M. ulcerans and its genomic profiles. We discuss reservoirs of M. ulcerans as an environmental pathogen and its environmental survival. We comprehensively discuss sporulation as a possible stress response mechanism and modelled endospore formation in M. ulcerans. At last, we highlighted sporulation associated markers, which upon expression trigger endospore formation.

Background: The detection of acid-fast bacilli in extrapulmonary tissue samples is challenging due to its paucibacillary nature. The present study assessed the utility of immunohistochemistry (IHC) using anti-Mycobacterium tuberculosis antibody (ab905) for detecting the presence of mycobacterial antigens in archived formalin-fixed paraffin-embedded (FFPE) tissues. Methods: FFPE tissues [surgical biopsies (n = 32) and post-mortem tissues (n = 8)] from clinically and histologically suggestive extrapulmonary tuberculosis (EPTB) cases at the Korle Bu Teaching Hospital, Accra, Ghana from 2015 to 2020 were stained with IHC (anti-Mycobacterium tuberculosis antibody) and Ziehl-Neelsen (ZN) stain. The staining outcomes of IHC and ZN were compared, and their sensitivity and specificity determined against histopathology as reference standard. Results: Lymph nodes were about 40% (16/40) of the samples analyzed. IHC stained positive in 43.8% (7/16) biopsies and 87.5% (4/5) post-mortem samples ranging from 43.8% (7/16) in lymph nodes to 80% (4/5) in gastrointestinal organs. The overall sensitivity for IHC was 52.50% (95% CI: 36.13%–68.49%) and 0% (95% CI: 0.00%–8.81%) for ZN. Specificity was 72.50% (95% CI: 56.11%–85.40%) and 75% (95% CI: 58.80–87.31%) for IHC and ZN respectively. Conclusions: IHC using anti-Mycobacterium tuberculosis antibody (ab905) can detect mycobacterial antigens in diverse range of paucibacillary extrapulmonary tissue sections. It is potentially a useful tool for the diagnosis of EPTB in FFPE tissues in a routine pathology laboratory.

Recurrent epidemics of cholera denote robust adaptive mechanisms of Vibrio cholerae for ecological shifting and persistence despite variable stress conditions. Tracking the evolution of pathobiological traits requires comparative genomic studies of isolates from endemic areas. Here, we investigated the genetic differentiation among V. cholerae clinical and environmental isolates by highlighting the genomic divergence associated with gene decay, genome plasticity, and the acquisition of virulence and adaptive traits. The clinical isolates showed high phylogenetic relatedness due to a higher frequency of shared orthologs and fewer gene variants in contrast to the evolutionarily divergent environmental strains. Divergence of the environmental isolates is linked to extensive genomic rearrangements in regions containing mobile genetic elements resulting in numerous breakpoints, relocations, and insertions coupled with the loss of virulence determinants acf, zot, tcp, and ctx in the genomic islands. Also, four isolates possessed the CRISPR-Cas systems with spacers specific for Vibrio phages and plasmids. Genome synteny and homology analysis of the CRISPR-Cas systems suggest horizontal acquisition. The marked differences in the distribution of other phage and plasmid defense systems such as Zorya, DdmABC, DdmDE, and type-I Restriction Modification systems among the isolates indicated a higher propensity for plasmid or phage disseminated traits in the environmental isolates. Our results reveal that V. cholerae strains undergo extensive genomic rearrangements coupled with gene acquisition, reflecting their adaptation during ecological shifts and pathogenicity.

Buruli ulcer (BU), a necrotic skin disease caused by Mycobacterium ulcerans, is mainly prevalent in West Africa, but cases have also been reported in other tropical parts of the world. It is the second most common mycobacterial disease after tuberculosis in Ghana and Côte d’Ivoire. Heterogeneity among M. ulcerans from different geographical locations has not been clearly elucidated, and some studies seem to suggest genetic differences between M. ulcerans in humans and in the environment. This study aimed at identifying genetic differences among M. ulcerans strains between two BU endemic countries: Ghana and Côte d’Ivoire. Clinical samples consisting of swabs, fine needle aspirates, and tissue biopsies of suspected BU lesions and environmental samples (e.g., water, biofilms from plants, soil, and detrital material) were analyzed. BU cases were confirmed via acid fast staining and PCR targeting the 16S rRNA, IS2404, IS2606, and ER domain genes present on M. ulcerans. Heterogeneity among M. ulcerans was determined through VNTR profiling targeting 10 loci. Eleven M. ulcerans genotypes were identified within the clinical samples in both Ghana and Côte d’Ivoire, whiles six M. ulcerans genotypes were found among the environmental samples. Clinical M. ulcerans genotypes C, D, F, and G were common in both countries. Genotype E was unique among the Ghanaian samples, whiles genotypes A, Z, J, and K were unique to the Ivorian samples. Environmental isolates were found to be more conserved compared with the clinical isolates. Genotype W was observed only among the Ghanaian environmental samples. Genotype D was found to be prominent in both clinical and environmental samples, suggesting evidence of possible transmission of M. ulcerans from the environment, particularly water bodies and biofilms from aquatic plants, to humans through open lesions on the skin.

Abstract Background Buruli ulcer (BU) is a skin disease caused by Mycobacterium ulcerans and is the second most common mycobacterial disease after tuberculosis in Ghana and Côte d’Ivoire. M. ulcerans produces mycolactone, an immunosuppressant macrolide toxin, responsible for the characteristic painless nature of the infection. Secondary infection of ulcers before, during and after treatment has been associated with delayed wound healing and resistance to streptomycin and rifampicin. However, not much is known of the bacteria causing these infections as well as antimicrobial drugs for treating the secondary microorganism. This study sought to identify secondary microbial infections in BU lesions and to determine their levels of antibiotic resistance due to the prolonged antibiotic therapy required for Buruli ulcer. Results Swabs from fifty-one suspected BU cases were sampled in the Amansie Central District from St. Peters Hospital (Jacobu) and through an active case surveillance. Forty of the samples were M. ulcerans (BU) positive. Secondary bacteria were identified in all sampled lesions (N = 51). The predominant bacteria identified in both BU and Non-BU groups were Staphylococci spp and Bacilli spp. The most diverse secondary bacteria were detected among BU patients who were not yet on antibiotic treatment. Fungal species identified were Candida spp, Penicillium spp and Trichodema spp. Selected secondary bacteria isolates were all susceptible to clarithromycin and amikacin among both BU and Non-BU patients. Majority, however, had high resistance to streptomycin. Conclusions Microorganisms other than M. ulcerans colonize and proliferate on BU lesions. Secondary microorganisms of BU wounds were mainly Staphylococcus spp, Bacillus spp and Pseudomonas spp. These secondary microorganisms were less predominant in BU patients under treatment compared to those without treatment. The delay in healing that are experienced by some BU patients could be as a result of these bacteria and fungi colonizing and proliferating in BU lesions. Clarithromycin and amikacin are likely suitable drugs for clearance of secondary infection of Buruli ulcer.

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.

Background: The use of face masks was a significant part of the WHO COVID-19 preventive protocols. While their usage has been effective, lack of adherence by individuals has been associated with discomfort and adverse side effects. This might facilitate unnecessary exposure to the SARS-CoV-2 virus, thereby increasing the incidence of COVID-19. This study assessed the side effects of prolonged mask-wearing and offers recommendations for present and future pandemics. Methods: Adverse side effects of face masks were evaluated from November 2021 to February 2022 with a structured Google Forms online questionnaire. The survey targeted regular and occasional face mask users around the world. All responders anonymously completed the survey, which included ten structured questions with a sub-section on the effects of the continuous use of face masks. The information obtained was analyzed using descriptive statistics, and the data were presented in graphs. Results: Almost 60% (1243) of the 2136 participants indicated discomfort while using face masks. Breathing difficulties and pain around the ears were cited as major causes of discomfort, accounting for 32% and 22%, respectively, of responses. Headaches were reported by 26.8% (572) of the respondents, with 44.6% experiencing one within 1 h of wearing a mask. Nine hundred and eight (908) respondents experienced nasal discomfort, while 412 individuals reported various skin-related discomfort, including excessive sweating around the mouth and acne. Conclusions: This study provides baseline data as to why there was less adherence to face mask use which includes headaches, skin irritation, ear pains, breathing difficulties, sore throat, dry eyes, and increased sweating around the mouth. As a result, this may contribute to an increased risk of infection. While COVID-19 lingers and the management of its undesirable effects persists into the future, it is vital that a superior mask design, concentrating on safety, comfort, and tolerability, be developed.

The evolving nature of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has necessitated periodic revisions of COVID-19 patient treatment and discharge guidelines. Since the identification of the first COVID-19 cases in November 2019, the World Health Organization (WHO) has played a crucial role in tackling the country-level pandemic preparedness and patient management protocols. Among others, the WHO provided a guideline on the clinical management of COVID-19 patients according to which patients can be released from isolation centers on the 10th day following clinical symptom manifestation, with a minimum of 72 additional hours following the resolution of symptoms. However, emerging direct evidence indicating the possibility of viral shedding 14 days after the onset of symptoms called for evaluation of the current WHO discharge recommendations. In this review article, we carried out comprehensive literature analysis of viral shedding with specific focus on the duration of viral shedding and infectivity in asymptomatic and symptomatic (mild, moderate, and severe forms) COVID-19 patients. Our literature search indicates that even though, there are specific instances where the current protocols may not be applicable ( such as in immune-compromised patients there is no strong evidence to contradict the current WHO discharge criteria.

Abstract Background Cholera has been endemic in Ghana since its detection in 1970. It has been shown that long-term survival of the bacteria may be attained in aquatic environments. Consequently, cholera outbreaks may be triggered predominantly in densely populated urban areas. We investigated clinical and environmental isolates of Vibrio cholerae O1 in Accra to determine their virulence genes, antibiotic susceptibility patterns and environmental factors maintaining their persistence in the environment. Methods Water samples from various sources were analyzed for the presence of V. cholerae O1 using culture methods. Forty clinical isolates from a previous cholera outbreak were included in the study for comparison. Antibiotic susceptibility patterns of the bacteria were determined by disc diffusion. Virulence genes were identified by analyzing genes for ctx, tcpA (tcpAEl Tor tcpACl), zot, ompW, rbfO1 and attRS using PCR. Physicochemical characteristics of water were investigated using standard methods. One-way ANOVA and student t - test were employed to analyze the relationship between physicochemical factors and the occurrence of V. cholerae O1. Results Eleven V. cholerae O1 strains were successfully isolated from streams, storage tanks and wells during the study period. All isolates were resistant to one or more of the eight antibiotics used. Multidrug resistance was observed in over 97% of the isolates. All isolates had genes for at least one virulence factor. Vibrio cholerae toxin gene was detected in 82.4% of the isolates. Approximately 81.8% of the isolates were positive for tcpAEl Tor gene, but also harbored the tcpAcl gene. Isolates were grouped into thirteen genotypes based on the genes analyzed. High temperature, salinity, total dissolved solids and conductivity was found to significantly correlate positively with isolation of V. cholerae O1. V. cholerae serotype Ogawa biotype El tor is the main biotype circulating in Ghana with the emergence of a hybrid strain. Conclusions Multidrug resistant V. cholerae O1 with different genotypes and pathogenicity are present in water sources and co-exist with non O1/O139 in the study area.

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.

Abstract Background Mycobacterium tuberculosis complex (MTBC) and Non-tuberculosis Mycobacterium (NTM) infections differ clinically, making rapid identification and drug susceptibility testing (DST) very critical for infection control and drug therapy. This study aims to use World Health Organization (WHO) approved line probe assay (LPA) to differentiate mycobacterial isolates obtained from tuberculosis (TB) prevalence survey in Ghana and to determine their drug resistance patterns. Methods A retrospective study was conducted whereby a total of 361 mycobacterial isolates were differentiated and their drug resistance patterns determined using GenoType Mycobacterium Assays: MTBC and CM/AS for differentiating MTBC and NTM as well MTBDRplus and NTM-DR for DST of MTBC and NTM respectively. Results Out of 361 isolates, 165 (45.7%) MTBC and 120 (33.2%) NTM (made up of 14 different species) were identified to the species levels whiles 76 (21.1%) could not be completely identified. The MTBC comprised 161 (97.6%) Mycobacterium tuberculosis and 4 (2.4%) Mycobacterium africanum. Isoniazid and rifampicin monoresistant MTBC isolates were 18/165 (10.9%) and 2/165(1.2%) respectively whiles 11/165 (6.7%) were resistant to both drugs. Majority 42/120 (35%) of NTM were M. fortuitum. DST of 28 M. avium complex and 8 M. abscessus complex species revealed that all were susceptible to macrolides (clarithromycin, azithromycin) and aminoglycosides (kanamycin, amikacin, and gentamicin). Conclusion Our research signifies an important contribution to TB control in terms of knowledge of the types of mycobacterium species circulating and their drug resistance patterns in Ghana.

Drugs targeting DNA and RNA in mammalian cells or viruses can also affect bacteria present in the host and thereby induce the bacterial SOS system. This has the potential to increase mutagenesis and the development of antimicrobial resistance (AMR). Here, we have examined nucleoside analogues (NAs) commonly used in anti-viral and anti-cancer therapies for potential effects on mutagenesis in Escherichia coli, using the rifampicin mutagenicity assay. To further explore the mode of action of the NAs, we applied E. coli deletion mutants, a peptide inhibiting Pol V (APIM-peptide) and metabolome and proteome analyses. Five out of the thirteen NAs examined, including three nucleoside reverse transcriptase inhibitors (NRTIs) and two anti-cancer drugs, increased the mutation frequency in E. coli by more than 25-fold at doses that were within reported plasma concentration range (Pl.CR), but that did not affect bacterial growth. We show that the SOS response is induced and that the increase in mutation frequency is mediated by the TLS polymerase Pol V. Quantitative mass spectrometry-based metabolite profiling did not reveal large changes in nucleoside phosphate or other central carbon metabolite pools, which suggests that the SOS induction is an effect of increased replicative stress. Our results suggest that NAs/NRTIs can contribute to the development of AMR and that drugs inhibiting Pol V can reverse this mutagenesis.

Buruli ulcer caused by Mycobacterium ulcerans (M. ulcerans) is identified by a pain-free cyst or edema which develops into a massive skin ulcer if left untreated. There are reports of chemoresistance, toxicity, noncompliance, and poor efficacy of current therapeutic options. Previously, we used cheminformatics approaches to identify potential antimycobacterial compounds targeting major receptors in M. ulcerans. In this paper, we sought to identify potential bioactive compounds by targeting Cystathionine gamma-synthase (CGS) MetB, a key receptor involved in methionine synthesis. Inhibition of methionine synthesis restricts the growth of M. ulcerans. Two potent inhibitors Juglone (IC50 0.7 +/− 0.7 µmol/L) and 9-hydroxy-alpha-lapachone (IC50 0.9 +/− 0.1 µmol/L) were used to generate 3D chemical feature pharmacophore model via LigandScout with a score of 0.9719. The validated model was screened against a pre-filtered library of 2530 African natural products. Compounds with fit scores above 66.40 were docked against the structure of CGS to generate hits. Three compounds, namely Gentisic 5-O glucoside (an isolate of African tree Alchornea cordifolia), Isoscutellarein (an isolate of Theobroma plant) and ZINC05854400, were identified as potential bioactive molecules with high binding affinities of −7.1, −8.4 and −8.4 kcal/mol against CGS, respectively. Novel structural insight into the binding mechanisms was elucidated using LigPlot+ and molecular dynamics simulations. All three molecules were predicted to possess antibacterial, anti-ulcerative, and dermatological properties. These compounds have the propensity to disrupt the methionine synthesis mechanisms with the potential of stagnating the growth of M. ulcerans. As a result of reasonably good pharmacological profiling, the three drug-like compounds are potential novel scaffolds that can be optimized into antimycobacterial molecules.

Background: Sachet water, popularly known as “pure water” has become an invaluable entity in most Ghanaian households. Despite its importance, there is no extensive nationwide investigations on its wholesomeness for consumption. The aim of this study was to determine the microbiological quality of 41 brands of sachet water sampled in 16 districts across 5 regions in Ghana. Methods: The samples were analyzed for the presence of total and fecal coliform (Escherichia coli) using the Colilert*- 18 Test Kit. Results: Majority of the samples (56.09%) were excellent, 4.87% satisfactory and 14.63% suspicious. Ten samples (24.4%) were unsatisfactory. For the degree of fecal contamination, (85.56%) were satisfactory, four (9.76%) were suspicious, and two others (4.88%) were unsatisfactory. The contaminations observed could be attributed to poor sanitary conditions (during and/or after production) and failure of some production facilities to adhere to standard manufacturing practices. Conclusion: Our data suggest that microbiological quality sachet water from some sources have not yet attained levels that make it absolutely pure and wholesome for consumption in many areas.

Background: The study was conducted to determine the bacterial composition and antibiotic susceptibility profiles of a research institute at the University of Ghana where workers and students spend about 70-85% of their lives in indoor and immediate-outdoor environments. This is imperative as one-third of the recognized infectious diseases are transmitted through airborne-route. Furthermore, the increasing rate of bacterial antimicrobial resistance associated with such environments poses serious public health challenges. Methods: A total of 42 airborne samples were collected from eight major sites at the Department of Biochemistry, Cell and Molecular Biology (BCMB), using passive bacterial sampling techniques. Standard phenotypic microbiological procedures were used to characterize the isolates. Antibiotic susceptibility profiles were determined using standard disk diffusion method and guidelines of Clinical and Laboratory Standards Institute (CLSI). Results: Four groups of bacterial isolates were identified from the total samples collected with Gram positive bacilli as the most common. All the isolates showed resistance to beta lactam and sulfonamide classes of antibiotics with full resistance (100%) to ampicillin and penicillin. In total, seven different anti-biotypes were observed with the highest susceptibility displayed towards tetracycline and gentamycin. Significantly, the various air sampling sites of the institute indicated the presence of bacteria with the majority showing multiple antibiotics resistance. Conclusions: Although the recovery of bacteria from supposed sterile environments calls for attention, the observed low contamination rate as compared to the WHO standard suggests a minimum risk of exposure of students and workers to airborne microbial contamination.

Buruli ulcer is a neglected tropical disease caused by the bacterium Mycobacterium ulcerans. Its virulence is attributed to the dermo-necrotic polyketide toxin mycolactone, whose synthesis is regressed when its iron acquisition system regulated by the iron-dependent regulator (ideR) is deactivated. Interfering with the activation mechanism of ideR to inhibit the toxin’s synthesis could serve as a possible cure for Buruli ulcer. The three-dimensional structure of the ideR for Mycobacterium ulcerans was generated using homology modeling. A library of 832 African natural products (AfroDB), as well as five known anti-mycobacterial compounds were docked against the metal binding site of the ideR. The area under the curve (AUC) values greater than 0.7 were obtained for the computed Receiver Operating Characteristics (ROC) curves, validating the docking protocol. The identified top hits were pharmacologically profiled using Absorption, Distribution, Metabolism, Elimination and Toxicity (ADMET) predictions and their binding mechanisms were characterized. Four compounds with ZINC IDs ZINC000018185774, ZINC000095485921, ZINC000014417338 and ZINC000005357841 emerged as leads with binding energies of −7.7 kcal/mol, −7.6 kcal/mol, −8.0 kcal/mol and −7.4 kcal/mol, respectively. Induced Fit Docking (IFD) was also performed to account for the protein’s flexibility upon ligand binding and to estimate the best plausible conformation of the complexes. Results obtained from the IFD were consistent with that of the molecular docking with the lead compounds forming interactions with known essential residues and some novel critical residues Thr14, Arg33 and Asp17. A hundred nanoseconds molecular dynamic simulations of the unbound ideR and its complexes with the respective lead compounds revealed changes in the ideR’s conformations induced by ZINC000018185774. Comparison of the lead compounds to reported potent inhibitors by docking them against the DNA-binding domain of the protein also showed the lead compounds to have very close binding affinities to those of the potent inhibitors. Interestingly, structurally similar compounds to ZINC000018185774 and ZINC000014417338, as well as analogues of ZINC000095485921, including quercetin are reported to possess anti-mycobacterial activity. Also, ZINC000005357841 was predicted to possess anti-inflammatory and anti-oxidative activities, which are relevant in Buruli ulcer and iron acquisition mechanisms, respectively. The leads are molecular templates which may serve as essential scaffolds for the design of future anti-mycobacterium ulcerans agents.

The transmission of Buruli ulcer (BU), caused by Mycobacterium ulcerans (MU), remains puzzling although a number of hypothesis including through bites of infected aquatic insects have been proposed. We report the results of experiments using ICR mice that give credence to our hypothesis that Acanthamoeba species may play a role in BU transmission. We cocultured MU N2 and MU 1615 which expresses red fluorescent protein (RFP) and Acanthamoeba polyphaga (AP), and confirmed infected AP by Ziehl-Neelsen (ZN) staining. We tested for viability of MU inside AP and observed strong RFP signals inside both trophozoites and cysts after 3 and 42 days of coculturing respectively. ICR mice were topically treated, either on shaved intact or shaved pinpricked rumps, with one of the following; MU N2 only (2.25 x 106 colony forming units [CFU] / ml), MU N2:AP coculture (2.96 x 104 CFU: 1.6 x 106 cells/ml), AP only (1.6 x 106 cells/ml), PYG medium and sterile distilled water. Both MU N2 only and MU N2:AP elicited reddening on day (D) 31; edema on D 45 and D 44 respectively, and ulcers on D 49 at pinpricked sites only. To ascertain infectivity and pathogenicity of MU N2 only and MU N2:AP, and compare their virulence, the standard mouse footpad inoculation method was used. MU N2:AP elicited reddening in footpads by D 3 compared to D 14 with MU N2 only of the same dose of MU N2 (2.96 x 104 CFU). ZN-stained MU were observed in both thin sectioned and homogenized lesions, and aspirates from infected sites. Viable MU N2 were recovered from cultures of the homogenates and aspirates. This study demonstrates in ICR mice MU transmission via passive infection, and shows that punctures in the skin are prerequisite for infection, and that coculturing of MU with AP enhances pathogenesis.

Buruli ulcer (BU) is caused by Mycobacterium ulcerans and is predominant in both tropical and subtropical regions. The neglected debilitating disease is characterized by chronic necrotizing skin lesions attributed to a mycolactone, which is a macrolide toxin secreted by M. ulcerans. The preferred treatment is surgical excision of the lesions followed by a prolonged combination antibiotic therapy using existing drugs such as rifampicin and streptomycin or clarithromycin. These antibiotics appear not to be adequately potent and efficacious against persistent and late stage ulcers. In addition, emerging drug resistance to treatment poses great challenges. There is a need to identify novel natural product-derived lead compounds, which are potent and efficacious for the treatment of Buruli ulcer. Natural products present a rich diversity of chemical compounds with proven activity against various infectious diseases, and therefore, are considered in this study. This study sought to computationally predict natural product-derived lead compounds with the potential to be developed further into potent drugs with better therapeutic efficacy than the existing anti-buruli ulcer compounds. The three-dimensional (3D) structure of Isocitrate lyase (ICL) of Mycobacterium ulcerans was generated using homology modeling and was further scrutinized with molecular dynamics simulations. A library consisting of 885 compounds retrieved from the AfroDb database was virtually screened against the validated ICL model using AutoDock Vina. AfroDb is a compendium of “drug-like” and structurally diverse 3D structures of natural products originating from different geographical regions in Africa. The molecular docking with the ICL model was validated by computing a Receiver Operating Characteristic (ROC) curve with a reasonably good Area Under the Curve (AUC) value of 0.89375. Twenty hit compounds, which docked firmly within the active site pocket of the ICL receptor, were assessed via in silico bioactivity and pharmacological profiling. The three compounds, which emerged as potential novel leads, comprise ZINC38143792 (Euscaphic acid), ZINC95485880, and ZINC95486305 with reasonable binding energies (high affinity) of −8.6, −8.6, and −8.8 kcal/mol, respectively. Euscaphic acid has been reported to show minimal inhibition against a drug-sensitive strain of M. tuberculosis. The other two leads were both predicted to possess dermatological activity while one was antibacterial. The leads have shown promising results pertaining to efficacy, toxicity, pharmacokinetic, and safety. These leads can be experimentally characterized to assess their anti-mycobacterial activity and their scaffolds may serve as rich skeletons for developing anti-buruli ulcer drugs.

Although several studies have associated Mycobacterium ulcerans (MU) infection, Buruli ulcer (BU), with slow moving water bodies, there is still no definite mode of transmission. Ecological and transmission studies suggest Variable Number Tandem Repeat (VNTR) typing as a useful tool to differentiate MU strains from other Mycolactone Producing Mycobacteria (MPM). Deciphering the genetic relatedness of clinical and environmental isolates is seminal to determining reservoirs, vectors and transmission routes. In this study, we attempted to source-track MU infections to specific water bodies by matching VNTR profiles of MU in human samples to those in the environment. Environmental samples were collected from 10 water bodies in four BU endemic communities in the Ashanti region, Ghana. Four VNTR loci in MU Agy99 genome, were used to genotype environmental MU ecovars, and those from 14 confirmed BU patients within the same study area. Length polymorphism was confirmed with sequencing. MU was present in the 3 different types of water bodies, but significantly higher in biofilm samples. Four MU genotypes, designated W, X, Y and Z, were typed in both human and environmental samples. Other reported genotypes were only found in water bodies. Animal trapping identified 1 mouse with lesion characteristic of BU, which was confirmed as MU infection. Our findings suggest that patients may have been infected from community associated water bodies. Further, we present evidence that small mammals within endemic communities could be susceptible to MU infections. M. ulcerans transmission could involve several routes where humans have contact with risk environments, which may be further compounded by water bodies acting as vehicles for disseminating strains.

Transmission of M. ulcerans, the etiological agent of Buruli ulcer, from the environment to humans remains an enigma despite decades of research. Major transmission hypotheses propose 1) that M. ulcerans is acquired through an insect bite or 2) that bacteria enter an existing wound through exposure to a contaminated environment. In studies reported here, a guinea pig infection model was developed to determine whether Buruli ulcer could be produced through passive inoculation of M. ulcerans onto a superficial abrasion. The choice of an abrasion model was based on the fact that most bacterial pathogens infecting the skin are able to infect an open lesion, and that abrasions are extremely common in children. Our studies show that after a 90d infection period, an ulcer was present at intra-dermal injection sites of all seven animals infected, whereas topical application of M. ulcerans failed to establish an infection. Mycobacterium ulcerans was cultured from all injection sites whereas infected abrasion sites healed and were culture negative. A 14d experiment was conducted to determine how long organisms persisted after inoculation. Mycobacterium ulcerans was isolated from abrasions at one hour and 24 hours post infection, but cultures from later time points were negative. Abrasion sites were qPCR positive up to seven days post infection, but negative at later timepoints. In contrast, M. ulcerans DNA was detected at intra-dermal injection sites throughout the study. M. ulcerans was cultured from injection sites at each time point. These results suggest that injection of M. ulcerans into the skin greatly facilitates infection and lends support for the role of an invertebrate vector or other route of entry such as a puncture wound or deep laceration where bacteria would be contained within the lesion. Infection through passive inoculation into an existing abrasion appears a less likely route of entry.