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Objective: This study aimed to describe the exposure levels to Dengue and Chikungunya viruses among individuals presenting with febrile illnesses in Ghana between January 2016 to June 2018. Methods: The study was conducted in health facilities in seven selected regions in Ghana; namely, Ashanti, Greater Accra, Northern, Upper West, Volta, and Western regions. Patients who met the case definition were enrolled in the study. A total of 1105 blood samples were collected from patients from 2016 to 2018 and serological analysis of Dengue and Chikungunya viruses were performed with ELISA IgM and IgG commercial kits (Abcam, Cambridge, UK). Results: Analysed results indicated that Dengue and Chikungunya viruses showed seropositivity of 62.0 % and 40.0 % respectively. All processed samples tested negative for Dengue and Chikungunya using the Polymerase Chain Reaction (PCR) assay. Greater Accra and Ashanti regions recorded the highest positivity for Chikungunya and Dengue fever viruses respectively. Conclusion: Though no detection of Dengue and Chikungunya using molecular tools, the seropositivity suggests the need for an established surveillance for arboviruses to monitor transmission of these pathogens for epidemic preparedness and response.

Purpose: Colistin is classified by the World Health Organization (WHO) as a critically important and last-resort antibiotic for the treatment of infections caused by carbapenem-resistant bacteria. However, colistin resistance mediated by chromosomal mutations or plasmid-linked mobilized colistin resistance (mcr) genes has emerged. Methods: Thirteen mcr-positive Aeromonas species isolated from water samples collected in Eastern Ghana were analyzed using whole-genome sequencing (WGS). Antimicrobial susceptibility was tested using the broth microdilution method. Resistome analysis was performed in silico using a web-based platform. Results: The minimum inhibitory concentration (MIC) of colistin for all except three isolates was > 4 μg/mL. Nine new sequence types were identified and whole-genome analysis revealed that the isolates harbored genes (mcr-3-related genes) that code for Lipid A phosphoethanolamine transferases on their chromosomes. BLAST analysis indicated that the amino acid sequences of the mcr-3-related genes detected varied from those previously reported and shared 79.04– 99.86% nucleotide sequence identity with publicly available mcr-3 variants and mcr-3-related phosphoethanolamine transferases. Analysis of the genetic context of mcr-3-related genes revealed that the genetic environment surrounding mcr-3-related genes was diverse among the different species of Aeromonas but conserved among isolates of the same species. Mcr-3-related-gene-IS-mcr-3-related-gene segment was identified in three Aeromonas caviae strains. Conclusion: The presence of mcr-3-related genes close to insertion elements is important for continuous monitoring to better understand how to control the mobilization and dissemination of antibiotic resistance genes. [ABSTRACT FROM AUTHOR]

The accurate diagnosis of nonmalarial febrile illnesses remains a large challenge in many malaria-endemic countries (1). The etiologic agents in this context are often not identified because of nonspecific clinical [...]

Rotavirus (RVA) is a leading cause of childhood gastroenteritis. RVA vaccines have reduced the global disease burden; however, the emergence of intergenogroup reassortant strains is a growing concern. During surveillance in Ghana, we observed the emergence of G9P[4] RVA strains in the fourth year after RVA vaccine introduction. To investigate whether Ghanaian G9P[4] strains also exhibited the DS-1-like backbone, as seen in reassortant G1/G3/G8/G9 strains found in other countries in recent years, this study determined the whole genome sequences of fifteen G9P[4] and two G2P[4] RVA strains detected during 2015–2016. The results reveal that the Ghanaian G9P[4] strains exhibited a double-reassortant genotype, with G9-VP7 and E6-NSP4 genes on a DS-1-like backbone (G9-P[4]-I2-R2-C2-M2-A2-N2-T2-E6-H2). Although they shared a common ancestor with G9P[4] DS-1-like strains from other countries, further intra-reassortment events were observed among the original G9P[4] and co-circulating strains in Ghana. In the post-vaccine era, there were significant changes in the distribution of RVA genotype constellations, with unique strains emerging, indicating an impact beyond natural cyclical fluctuations. However, reassortant strains may exhibit instability and have a limited duration of appearance. Current vaccines have shown efficacy against DS-1-like strains; however, ongoing surveillance in fully vaccinated children is crucial for addressing concerns about long-term effectiveness. [ABSTRACT FROM AUTHOR]

Extra-intestinal pathogenic Escherichia coli (ExPEC) is one of the world's leading causes of bloodstream infections with high mortality. Sequence type 410 (ST410) is an emerging ExPEC clone resistant to a wide range of antibiotics. In this study, we investigated the epidemiology of 21 ST410 E. coli isolates from two Ghanaian hospitals. We also investigated the isolates within a global context to provide further insight into the dissemination of this highly pathogenic clone. A phylogenetic tree of the 21 isolate genomes, along with 102 others from global collection, was constructed representing the ensuing clades and sub-clades of the ST: A/H53, B2/H24R, B3/H24Rx, and B4/H24RxC. The carbapenem-resistant sub-clade B4/H24RxC is reported to have emerged in the early 2000s when ST410 acquired an IncX3 plasmid carrying a bla OXA–181 carbapenemase gene, and a second carbapenemase gene, bla NDM–5, on a conserved IncFII plasmid in 2014. We identified, in this study, one bla OXA–181–carrying isolate belonging to B4/H24RxC sub-lineage and one carrying bla NDM–1 belonging to sub-lineage B3/H24Rx. The bla OXA–181 gene was found on a 51kb IncX3 plasmid; pEc1079_3. The majority (12/21) of our Ghanaian isolates were clustered with international strains described by previous authors as closely related strains to B4/H24RxC. Six others were clustered among the ESBL-associated sub-lineage B3/H24Rx and three with the globally disseminated sub-lineage B4/H24RxC. The results show that this highly pathogenic clone is disseminated in Ghana and, given its ability to transmit between hosts, it poses a serious threat and should be monitored closely. [ABSTRACT FROM AUTHOR]

The characteristics of microbial degradation of the sodium acrylate oligomer by Arthrobacter sp. strain NO-18 isolated from soil were reported. The structure of the terminal group has little effect on degradation, but the main chain structure affects biodegradation by this strain. It grew on acrylic acid, propionic acid, glutaric acid, 2-methylglutaric acid and 1,3,5-pentanetricarboxylic acid. The results suggested that the acrylic unit was susceptible to attack by this strain.

A maltotriose-forming alpha-amylase from the haloalkiliphilic microorganism Natronococcus sp. strain Ah-36 was isolated and purified by ethanol precipitation. Characterization studies showed that the 74-kDa alpha-amylase exhibits maximal activity at pH 8.7 and 55 degrees celsius at a salt concentration of 2.5 M NaCl. At low ionic strength, amylase activity was irreversibly inactivated. Amino acid sequence analysis showed that the Ah-36 amylase has a high content of glutamic acid and glutamine. Enzyme acitivity analysis showed that the action of this amylase is endolytic and may also exhibit a transglycosylating process.

Nephrotic syndrome (NS) is a renal disease characterized by severe proteinuria and hypoproteinemia. Although several single-gene mutations have been associated with steroid-resistant NS, causative genes for steroid-sensitive NS (SSNS) have not been clarified. While seeking to identify causative genes associated with SSNS by whole-exome sequencing, we found compound heterozygous variants/mutations (c.524T>C; p.I175T and c.662G>A; p.R221H) of the interleukin-1 receptor accessory protein (IL1RAP) gene in two siblings with SSNS. The siblings' parents are healthy, and each parent carries a different heterozygous IL1RAP variant/mutation. Since IL1RAP is a critical subunit of the functional interleukin-1 receptor (IL-1R), we investigated the effect of these variants on IL-1R subunit function. When stimulated with IL-1β, peripheral blood mononuclear cells from the siblings with SSNS produced markedly lower levels of cytokines compared with cells from healthy family members. Moreover, IL-1R with a variant IL1RAP subunit, reconstituted on a hematopoietic cell line, had impaired binding ability and low reactivity to IL-1β. Thus, the amino acid substitutions in IL1RAP found in these NS patients are dysfunctional variants/mutations. Furthermore, in the kidney of Il1rap −/− mice, the number of myeloid-derived suppressor cells, which require IL-1β for their differentiation, was markedly reduced although these mice did not show significantly increased proteinuria in acute nephrotic injury with lipopolysaccharide treatment. Together, these results identify two IL1RAP variants/mutations in humans for the first time and suggest that IL1RAP might be a causative gene for familial NS. [ABSTRACT FROM AUTHOR]

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 FROM AUTHOR]