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1.
PLoS Genet ; 19(3): e1010678, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36972302

RESUMEN

Cross-resistance to insecticides in multiple resistant malaria vectors is hampering resistance management. Understanding its underlying molecular basis is critical to implementation of suitable insecticide-based interventions. Here, we established that the tandemly duplicated cytochrome P450s, CYP6P9a/b are driving carbamate and pyrethroid cross-resistance in Southern African populations of the major malaria vector Anopheles funestus. Transcriptome sequencing revealed that cytochrome P450s are the most over-expressed genes in bendiocarb and permethrin-resistant An. funestus. The CYP6P9a and CYP6P9b genes are overexpressed in resistant An. funestus from Southern Africa (Malawi) versus susceptible An. funestus (Fold change (FC) is 53.4 and 17 respectively), while the CYP6P4a and CYP6P4b genes are overexpressed in resistant An. funestus in Ghana, West Africa, (FC is 41.1 and 17.2 respectively). Other up-regulated genes in resistant An. funestus include several additional cytochrome P450s (e.g. CYP9J5, CYP6P2, CYP6P5), glutathione-S transferases, ATP-binding cassette transporters, digestive enzymes, microRNA and transcription factors (FC<7). Targeted enrichment sequencing strongly linked a known major pyrethroid resistance locus (rp1) to carbamate resistance centering around CYP6P9a/b. In bendiocarb resistant An. funestus, this locus exhibits a reduced nucleotide diversity, significant p-values when comparing allele frequencies, and the most non-synonymous substitutions. Recombinant enzyme metabolism assays showed that both CYP6P9a/b metabolize carbamates. Transgenic expression of CYP6P9a/b in Drosophila melanogaster revealed that flies expressing both genes were significantly more resistant to carbamates than controls. Furthermore, a strong correlation was observed between carbamate resistance and CYP6P9a genotypes with homozygote resistant An. funestus (CYP6P9a and the 6.5kb enhancer structural variant) exhibiting a greater ability to withstand bendiocarb/propoxur exposure than homozygote CYP6P9a_susceptible (e.g Odds ratio = 20.8, P<0.0001 for bendiocarb) and heterozygotes (OR = 9.7, P<0.0001). Double homozygote resistant genotype (RR/RR) were even more able to survive than any other genotype combination showing an additive effect. This study highlights the risk that pyrethroid resistance escalation poses to the efficacy of other classes of insecticides. Available metabolic resistance DNA-based diagnostic assays should be used by control programs to monitor cross-resistance between insecticides before implementing new interventions.


Asunto(s)
Anopheles , Insecticidas , Malaria , Piretrinas , Animales , Insecticidas/farmacología , Carbamatos/metabolismo , Piretrinas/metabolismo , Anopheles/genética , Drosophila melanogaster , Resistencia a los Insecticidas/genética , Mosquitos Vectores/genética , Citocromos/metabolismo , Ghana
2.
Am J Hum Genet ; 109(5): 900-908, 2022 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-35353984

RESUMEN

Polygenic risk scores (PRSs) for a variety of diseases have recently been shown to have relative risks that depend on age, and genetic relative risks decrease with increasing age. A refined understanding of the age dependency of PRSs for a disease is important for personalized risk predictions and risk stratification. To further evaluate how the PRS relative risk for prostate cancer depends on age, we refined analyses for a validated PRS for prostate cancer by using 64,274 prostate cancer cases and 46,432 controls of diverse ancestry (82.8% European, 9.8% African American, 3.8% Latino, 2.8% Asian, and 0.8% Ghanaian). Our strategy applied a novel weighted proportional hazards model to case-control data to fully utilize age to refine how the relative risk decreased with age. We found significantly greater relative risks for younger men (age 30-55 years) compared with older men (70-88 years) for both relative risk per standard deviation of the PRS and dichotomized according to the upper 90th percentile of the PRS distribution. For the largest European ancestral group that could provide reliable resolution, the log-relative risk decreased approximately linearly from age 50 to age 75. Despite strong evidence of age-dependent genetic relative risk, our results suggest that absolute risk predictions differed little from predictions that assumed a constant relative risk over ages, from short-term to long-term predictions, simplifying implementation of risk discussions into clinical practice.


Asunto(s)
Predisposición Genética a la Enfermedad , Neoplasias de la Próstata , Adulto , Anciano , Estudio de Asociación del Genoma Completo , Ghana , Humanos , Masculino , Persona de Mediana Edad , Herencia Multifactorial/genética , Neoplasias de la Próstata/genética , Factores de Riesgo
3.
Lancet ; 403(10437): 1660-1670, 2024 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-38583454

RESUMEN

BACKGROUND: The RTS,S/AS01E malaria vaccine (RTS,S) was introduced by national immunisation programmes in Ghana, Kenya, and Malawi in 2019 in large-scale pilot schemes. We aimed to address questions about feasibility and impact, and to assess safety signals that had been observed in the phase 3 trial that included an excess of meningitis and cerebral malaria cases in RTS,S recipients, and the possibility of an excess of deaths among girls who received RTS,S than in controls, to inform decisions about wider use. METHODS: In this prospective evaluation, 158 geographical clusters (66 districts in Ghana; 46 sub-counties in Kenya; and 46 groups of immunisation clinic catchment areas in Malawi) were randomly assigned to early or delayed introduction of RTS,S, with three doses to be administered between the ages of 5 months and 9 months and a fourth dose at the age of approximately 2 years. Primary outcomes of the evaluation, planned over 4 years, were mortality from all causes except injury (impact), hospital admission with severe malaria (impact), hospital admission with meningitis or cerebral malaria (safety), deaths in girls compared with boys (safety), and vaccination coverage (feasibility). Mortality was monitored in children aged 1-59 months throughout the pilot areas. Surveillance for meningitis and severe malaria was established in eight sentinel hospitals in Ghana, six in Kenya, and four in Malawi. Vaccine uptake was measured in surveys of children aged 12-23 months about 18 months after vaccine introduction. We estimated that sufficient data would have accrued after 24 months to evaluate each of the safety signals and the impact on severe malaria in a pooled analysis of the data from the three countries. We estimated incidence rate ratios (IRRs) by comparing the ratio of the number of events in children age-eligible to have received at least one dose of the vaccine (for safety outcomes), or age-eligible to have received three doses (for impact outcomes), to that in non-eligible age groups in implementation areas with the equivalent ratio in comparison areas. To establish whether there was evidence of a difference between girls and boys in the vaccine's impact on mortality, the female-to-male mortality ratio in age groups eligible to receive the vaccine (relative to the ratio in non-eligible children) was compared between implementation and comparison areas. Preliminary findings contributed to WHO's recommendation in 2021 for widespread use of RTS,S in areas of moderate-to-high malaria transmission. FINDINGS: By April 30, 2021, 652 673 children had received at least one dose of RTS,S and 494 745 children had received three doses. Coverage of the first dose was 76% in Ghana, 79% in Kenya, and 73% in Malawi, and coverage of the third dose was 66% in Ghana, 62% in Kenya, and 62% in Malawi. 26 285 children aged 1-59 months were admitted to sentinel hospitals and 13 198 deaths were reported through mortality surveillance. Among children eligible to have received at least one dose of RTS,S, there was no evidence of an excess of meningitis or cerebral malaria cases in implementation areas compared with comparison areas (hospital admission with meningitis: IRR 0·63 [95% CI 0·22-1·79]; hospital admission with cerebral malaria: IRR 1·03 [95% CI 0·61-1·74]). The impact of RTS,S introduction on mortality was similar for girls and boys (relative mortality ratio 1·03 [95% CI 0·88-1·21]). Among children eligible for three vaccine doses, RTS,S introduction was associated with a 32% reduction (95% CI 5-51%) in hospital admission with severe malaria, and a 9% reduction (95% CI 0-18%) in all-cause mortality (excluding injury). INTERPRETATION: In the first 2 years of implementation of RTS,S, the three primary doses were effectively deployed through national immunisation programmes. There was no evidence of the safety signals that had been observed in the phase 3 trial, and introduction of the vaccine was associated with substantial reductions in hospital admission with severe malaria. Evaluation continues to assess the impact of four doses of RTS,S. FUNDING: Gavi, the Vaccine Alliance; the Global Fund to Fight AIDS, Tuberculosis and Malaria; and Unitaid.


Asunto(s)
Estudios de Factibilidad , Programas de Inmunización , Vacunas contra la Malaria , Malaria Cerebral , Humanos , Ghana/epidemiología , Malaui/epidemiología , Lactante , Femenino , Kenia/epidemiología , Vacunas contra la Malaria/administración & dosificación , Vacunas contra la Malaria/efectos adversos , Masculino , Preescolar , Malaria Cerebral/epidemiología , Malaria Cerebral/mortalidad , Estudios Prospectivos , Malaria Falciparum/prevención & control , Malaria Falciparum/epidemiología , Meningitis/epidemiología , Meningitis/prevención & control
4.
J Virol ; 98(3): e0183823, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38426726

RESUMEN

Nipah virus (NiV) is a highly lethal, zoonotic Henipavirus (HNV) that causes respiratory and neurological signs and symptoms in humans. Similar to other paramyxoviruses, HNVs mediate entry into host cells through the concerted actions of two surface glycoproteins: a receptor-binding protein (RBP) that mediates attachment and a fusion glycoprotein (F) that triggers fusion in an RBP-dependent manner. NiV uses ephrin-B2 (EFNB2) and ephrin-B3 (EFNB3) as entry receptors. Ghana virus (GhV), a novel HNV identified in a Ghanaian bat, uses EFNB2 but not EFNB3. In this study, we employ a structure-informed approach to identify receptor-interfacing residues and systematically introduce GhV-RBP residues into a NiV-RBP backbone to uncover the molecular determinants of EFNB3 usage. We reveal two regions that severely impair EFNB3 binding by NiV-RBP and EFNB3-mediated entry by NiV pseudotyped viral particles. Further analyses uncovered two-point mutations (NiVN557SGhV and NiVY581TGhV) pivotal for this phenotype. Moreover, we identify NiV interaction with Y120 of EFNB3 as important for the usage of this receptor. Beyond these EFNB3-related findings, we reveal two domains that restrict GhV binding of EFNB2, confirm the HNV-head as an immunodominant target for polyclonal and monoclonal antibodies, and describe putative epitopes for GhV- and NiV-specific monoclonal antibodies. Cumulatively, the work presented here generates useful reagents and tools that shed insight to residues important for NiV usage of EFNB3, reveal regions critical for GhV binding of EFNB2, and describe putative HNV antibody-binding epitopes. IMPORTANCE: Hendra virus and Nipah virus (NiV) are lethal, zoonotic Henipaviruses (HNVs) that cause respiratory and neurological clinical features in humans. Since their initial outbreaks in the 1990s, several novel HNVs have been discovered worldwide, including Ghana virus. Additionally, there is serological evidence of zoonotic transmission, lending way to concerns about future outbreaks. HNV infection of cells is mediated by the receptor-binding protein (RBP) and the Fusion protein (F). The work presented here identifies NiV RBP amino acids important for the usage of ephrin-B3 (EFNB3), a receptor highly expressed in neurons and predicted to be important for neurological clinical features caused by NiV. This study also characterizes epitopes recognized by antibodies against divergent HNV RBPs. Together, this sheds insight to amino acids critical for HNV receptor usage and antibody binding, which is valuable for future studies investigating determinants of viral pathogenesis and developing antibody therapies.


Asunto(s)
Infecciones por Henipavirus , Henipavirus , Receptores Virales , Humanos , Aminoácidos/genética , Anticuerpos Monoclonales/metabolismo , Proteínas Portadoras/metabolismo , Efrina-B3/genética , Efrina-B3/química , Efrina-B3/metabolismo , Epítopos/genética , Epítopos/metabolismo , Ghana , Virus Hendra/metabolismo , Henipavirus/clasificación , Henipavirus/genética , Henipavirus/metabolismo , Mutagénesis , Virus Nipah/metabolismo , Proteínas del Envoltorio Viral/genética , Internalización del Virus , Receptores Virales/metabolismo
5.
FASEB J ; 38(13): e23741, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38896550

RESUMEN

Access to scientific meetings and conferences is limited in low- and middle-income countries (LMIC). Efforts are being implemented to rectify this issue through short workshops, seminars, and conferences. Sena Institute of Technology (SIT), a nonprofit research institute based in Ghana, is one such organization championing this initiative. Through a partnership with the Federation of American Societies for Experimental Biology (FASEB), SIT hosted the first FASEB conference in Africa from August 27-30, 2023 in Ghana. The 3-day conference brought together scientists specialized in imaging, genetics, and cell biology from across the globe to discuss the theme "Imaging Cellular and Chromosome Dynamics." The Ghanaian Ministry of Environment, Science, Technology and Innovation (MESTI) and the Ghana Tourism Authority (GTA) provided local support to the meeting. At the end of the conference, participants recommended continuing engagement and the organization of more such meetings on the African continent.


Asunto(s)
Cromosomas , Humanos , Ghana
6.
Am J Respir Crit Care Med ; 209(6): 716-726, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38016085

RESUMEN

Rationale: The impact of a household air pollution (HAP) stove intervention on child lung function has been poorly described. Objectives: To assess the effect of a HAP stove intervention for infants prenatally to age 1 on, and exposure-response associations with, lung function at child age 4. Methods: The Ghana Randomized Air Pollution and Health Study randomized pregnant women to liquefied petroleum gas (LPG), improved biomass, or open-fire (control) stove conditions through child age 1. We quantified HAP exposure by repeated maternal and child personal carbon monoxide (CO) exposure measurements. Children performed oscillometry, an effort-independent lung function measurement, at age 4. We examined associations between Ghana Randomized Air Pollution and Health Study stove assignment and prenatal and infant CO measurements and oscillometry using generalized linear regression models. We used reverse distributed lag models to examine time-varying associations between prenatal CO and oscillometry. Measurements and Main Results: The primary oscillometry measure was reactance at 5 Hz, X5, a measure of elastic and inertial lung properties. Secondary measures included total, large airway, and small airway resistance at 5 Hz, 20 Hz, and the difference in resistance at 5 Hz and 20 Hz (R5, R20, and R5-20, respectively); area of reactance (AX); and resonant frequency. Of the 683 children who attended the lung function visit, 567 (83%) performed acceptable oscillometry. A total of 221, 106, and 240 children were from the LPG, improved biomass, and control arms, respectively. Compared with control, the improved biomass stove condition was associated with lower reactance at 5 Hz (X5 z-score: ß = -0.25; 95% confidence interval [CI] = -0.39, -0.11), higher large airway resistance (R20 z-score: ß = 0.34; 95% CI = 0.23, 0.44), and higher AX (AX z-score: ß = 0.16; 95% CI = 0.06, 0.26), which is suggestive of overall worse lung function. The LPG stove condition was associated with higher X5 (X5 score: ß = 0.16; 95% CI = 0.01, 0.31) and lower small airway resistance (R5-20 z-score: ß = -0.15; 95% CI = -0.30, 0.0), which is suggestive of better small airway function. Higher average prenatal CO exposure was associated with higher R5 and R20, and distributed lag models identified sensitive windows of exposure between CO and X5, R5, R20, and R5-20. Conclusions: These data support the importance of prenatal HAP exposure on child lung function. Clinical trial registered with www.clinicaltrials.gov (NCT01335490).


Asunto(s)
Contaminación del Aire , Preescolar , Femenino , Humanos , Lactante , Embarazo , Contaminación del Aire/efectos adversos , Resistencia de las Vías Respiratorias/fisiología , Ghana/epidemiología , Pulmón , Mujeres Embarazadas
7.
J Infect Dis ; 229(1): 203-213, 2024 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-37804095

RESUMEN

Members of the Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) family are important targets for protective immunity. Abnormal display of PfEMP1 on the surfaces of infected erythrocytes (IEs) and reduced cytoadhesion have been demonstrated in hemoglobin (Hb) AS and HbAC, inherited blood disorders associated with protection against severe P. falciparum malaria. We found that Ghanaian children with HbAS had lower levels of immunoglobulin G against several PfEMP1 variants and that this reactivity increased more slowly with age than in their HbAA counterparts. Moreover, children with HbAS have lower total parasite biomass than those with HbAA at comparable peripheral parasitemias, suggesting impaired cytoadhesion of HbAS IEs in vivo and likely explaining the slower acquisition of PfEMP1-specific immunoglobulin G in this group. In contrast, the function of acquired antibodies was comparable among Hb groups and appears to be intact and sufficient to control parasitemia via opsonization and phagocytosis of IEs.


Asunto(s)
Hemoglobina Falciforme , Malaria Falciparum , Niño , Humanos , Hemoglobina Falciforme/metabolismo , Plasmodium falciparum , Malaria Falciparum/parasitología , Ghana , Proteínas Protozoarias , Eritrocitos/parasitología , Inmunoglobulina G , Anticuerpos Antiprotozoarios , Proteínas de la Membrana/metabolismo
8.
J Infect Dis ; 230(2): e486-e495, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-38438123

RESUMEN

BACKGROUND: The RTS,S/AS01E (RTS,S) malaria vaccine is recommended for children in malaria endemic areas. This phase 2b trial evaluates RTS,S fractional- and full-dose regimens in Ghana and Kenya. METHODS: In total, 1500 children aged 5-17 months were randomized (1:1:1:1:1) to receive RTS,S or rabies control vaccine. RTS,S groups received 2 full RTS,S doses at months 0 and 1 and either full (groups R012-20, R012-14-26) or fractional doses (one-fifth; groups Fx012-14-26, Fx017-20-32). RESULTS: At month 32 post-dose 1, vaccine efficacy against clinical malaria (all episodes) ranged from 38% (R012-20; 95% confidence interval [CI]: 24%-49%) to 53% (R012-14-26; 95% CI: 42%-62%). Vaccine impact (cumulative number of cases averted/1000 children vaccinated) was 1344 (R012-20), 2450 (R012-14-26), 2273 (Fx012-14-26), and 2112 (Fx017-20-32). To account for differences in vaccine volume (fractional vs full dose; post hoc analysis), we estimated cases averted/1000 RTS,S full-dose equivalents: 336 (R012-20), 490 (R012-14-26), 874 (Fx012-14-26), and 880 (Fx017-20-32). CONCLUSIONS: Vaccine efficacy was similar across RTS,S groups. Vaccine impact accounting for full-dose equivalence suggests that using fractional-dose regimens could be a viable dose-sparing strategy. If maintained through trial end, these observations underscore the means to reduce cost per regimen thus maximizing impact and optimizing supply. CLINICAL TRIALS REGISTRATION: NCT03276962 (ClinicalTrials.gov).


Asunto(s)
Vacunas contra la Malaria , Malaria Falciparum , Eficacia de las Vacunas , Humanos , Vacunas contra la Malaria/administración & dosificación , Vacunas contra la Malaria/inmunología , Ghana , Lactante , Kenia , Femenino , Masculino , Malaria Falciparum/prevención & control , Malaria Falciparum/epidemiología , Esquemas de Inmunización , Malaria/prevención & control , Plasmodium falciparum/inmunología
9.
Emerg Infect Dis ; 30(3): 605-608, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38316032

RESUMEN

The invasive Anopheles stephensi mosquito has rapidly expanded in range in Africa over the past decade. Consistent with World Health Organization guidelines, routine entomologic surveillance of malaria vectors in Accra, Ghana, now includes morphologic and molecular surveillance of An. stephensi mosquitoes. We report detection of An. stephensi mosquitoes in Ghana.


Asunto(s)
Anopheles , Malaria , Animales , Ghana/epidemiología , Mosquitos Vectores , Malaria/epidemiología
10.
BMC Immunol ; 25(1): 14, 2024 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-38336647

RESUMEN

BACKGROUND: Haemoglobin (Hb) variants such as sickle cell trait (SCT/HbAS) play a role in protecting against clinical malaria, but little is known about the development of immune responses against malaria parasite (Plasmodium falciparum surface protein 230 (Pfs230) and Plasmodium falciparum erythrocyte binding antigen 175 region-3 (PfEBA175-3R)) and vector (on the An. gambiae Salivary Gland Protein-6 peptide 1 (gSG6-P1)) antigens in individuals with variants Hb genotypes. This study assessed antibody (IgG) responses against malaria parasite, Pfs230 and PfEBA175-3R and vector, gSG6-P1 in febrile individuals with variant Hb genotypes. METHODS: The study was conducted on symptomatic malaria patients attending various healthcare facilities throughout Ghana. Microscopy and ELISA were used to determine the natural IgG antibody levels of gSG6-P1, PfEBA175-3R & Pfs230, and Capillarys 2 Flex Piercing was used for Hb variants determination. RESULTS: Of the 600 symptomatic malaria patients, 50.0% of the participants had malaria parasites by microscopy. The majority 79.0% (398/504) of the participants had Hb AA, followed by HbAS variant at 11.3% (57/504) and HbAC 6.7% (34/504). There were significantly (p < 0.0001) reduced levels of gSG6-P1 IgG in individuals with both HbAC and HbAS genotypes compared to the HbAA genotype. The levels of gSG6-P1 IgG were significantly (p < 0.0001) higher in HbAS compared to HbAC. Similarly, Pfs230 IgG and PfEBA-175-3R IgG distributions observed across the haemoglobin variants were significantly higher in HbAC relative to HbAS. CONCLUSION: The study has shown that haemoglobin variants significantly influence the pattern of anti-gSG6-P1, Pfs230, and PfEBA-175 IgG levels in malaria-endemic population. The HbAS genotype is suggested to confer protection against malaria infection. Reduced exposure to infection ultimately reduces the induction of antibodies targeted against P. falciparum antigens.


Asunto(s)
Antígenos de Grupos Sanguíneos , Malaria Falciparum , Malaria , Humanos , Ghana/epidemiología , Hemoglobinas/metabolismo , Malaria Falciparum/epidemiología , Plasmodium falciparum , Genotipo , Inmunoglobulina G , Inmunidad
11.
BMC Immunol ; 25(1): 44, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38987710

RESUMEN

BACKGROUND: Malaria is a life-threatening parasitic disease typically transmitted through the bite of an infected Anopheles mosquito. There is ample evidence showing the potential of malaria infection to affect the counts of lymphocyte subpopulations in the peripheral blood, but the extent of alteration might not be consistent in all geographical locations, due to several local factors. Although Ghana is among the malaria-endemic countries, there is currently no available data on the level of alterations that occur in the counts of lymphocyte subpopulations during P. falciparum malaria infection among adults. AIM: The study was to determine the immunophenotypic alterations in the level of peripheral blood lymphocytes and their subsets in adults with uncomplicated P. falciparum malaria infection and apparently healthy participants. METHODS: The study was a cross-sectional comparative study conducted in two municipalities of the Volta region of Ghana. Blood samples were collected from study participants and taken through serology (P. falciparum/Pan Rapid Diagnostic Kits), microscopy (Thick and thin blood films) and Haematological (Flow cytometric and Full blood count) analysis. RESULTS: A total of 414 participants, comprising 214 patients with malaria and 200 apparently healthy individuals (controls) were recruited into this study. Parasite density of the malaria patients ranged from 75/µL to 84,364/µL, with a mean of 3,520/µL. It was also observed that the total lymphocytes slightly decreased in the P. falciparum-infected individuals (Mean ± SD: 2.08 ± 4.93 × 109/L) compared to the control group (Mean ± SD: 2.47 ± 0.80 × 109/L). Again, there was a significant moderate positive correlation between parasite density and haematocrit levels (r = 0.321, p < 0.001). Apart from CD45 + T-cells, more people in the control group had normal values for the lymphocyte subsets measured compared to the malaria patients. CONCLUSIONS: From the results obtained, there was high parasite density among the malaria patients suggestive of high intensity of infection in the case group. The malaria patients again showed considerable haematological alterations in lymphocyte sub-sets and the parasite density appeared to be strongly associated with CD4 + T-cell reduction. Also, the parasite density significantly associated with decreasing haematocrit levels. This indicates that lymphocyte subset enumeration can be used to effectively support malaria diagnosis.


Asunto(s)
Inmunofenotipificación , Malaria Falciparum , Plasmodium falciparum , Humanos , Malaria Falciparum/inmunología , Malaria Falciparum/sangre , Malaria Falciparum/diagnóstico , Malaria Falciparum/parasitología , Masculino , Femenino , Adulto , Plasmodium falciparum/inmunología , Estudios Transversales , Ghana , Persona de Mediana Edad , Adulto Joven , Subgrupos Linfocitarios/inmunología , Adolescente , Linfocitos/inmunología , Recuento de Linfocitos
12.
J Antimicrob Chemother ; 79(7): 1529-1539, 2024 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-38751093

RESUMEN

OBJECTIVES: Comprehensive data on the genomic epidemiology of hospital-associated Klebsiella pneumoniae in Ghana are scarce. This study investigated the genomic diversity, antimicrobial resistance patterns, and clonal relationships of 103 clinical K. pneumoniae isolates from five tertiary hospitals in Southern Ghana-predominantly from paediatric patients aged under 5 years (67/103; 65%), with the majority collected from urine (32/103; 31%) and blood (25/103; 24%) cultures. METHODS: We generated hybrid Nanopore-Illumina assemblies and employed Pathogenwatch for genotyping via Kaptive [capsular (K) locus and lipopolysaccharide (O) antigens] and Kleborate (antimicrobial resistance and hypervirulence) and determined clonal relationships using core-genome MLST (cgMLST). RESULTS: Of 44 distinct STs detected, ST133 was the most common, comprising 23% of isolates (n = 23/103). KL116 (28/103; 27%) and O1 (66/103; 64%) were the most prevalent K-locus and O-antigen types. Single-linkage clustering highlighted the global spread of MDR clones such as ST15, ST307, ST17, ST11, ST101 and ST48, with minimal allele differences (1-5) from publicly available genomes worldwide. Conversely, 17 isolates constituted novel clonal groups and lacked close relatives among publicly available genomes, displaying unique genetic diversity within our study population. A significant proportion of isolates (88/103; 85%) carried resistance genes for ≥3 antibiotic classes, with the blaCTX-M-15 gene present in 78% (n = 80/103). Carbapenem resistance, predominantly due to blaOXA-181 and blaNDM-1 genes, was found in 10% (n = 10/103) of the isolates. CONCLUSIONS: Our findings reveal a complex genomic landscape of K. pneumoniae in Southern Ghana, underscoring the critical need for ongoing genomic surveillance to manage the substantial burden of antimicrobial resistance.


Asunto(s)
Antibacterianos , Variación Genética , Infecciones por Klebsiella , Klebsiella pneumoniae , Tipificación de Secuencias Multilocus , Centros de Atención Terciaria , Humanos , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/efectos de los fármacos , Klebsiella pneumoniae/aislamiento & purificación , Centros de Atención Terciaria/estadística & datos numéricos , Ghana/epidemiología , Infecciones por Klebsiella/microbiología , Infecciones por Klebsiella/epidemiología , Antibacterianos/farmacología , Preescolar , Lactante , Pruebas de Sensibilidad Microbiana , Genotipo , Femenino , Masculino , Niño , Farmacorresistencia Bacteriana Múltiple/genética , Infección Hospitalaria/microbiología , Infección Hospitalaria/epidemiología , Genoma Bacteriano , Farmacorresistencia Bacteriana/genética , Adulto , Epidemiología Molecular
13.
HIV Med ; 25(5): 577-586, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38240173

RESUMEN

BACKGROUND: Antiretroviral therapy (ART)-associated metabolic abnormalities, including impairment of glucose metabolism, are prevalent in adults living with HIV. However, the prevalence and pathogenesis of impaired glucose metabolism in children and adolescents living with HIV, particularly in sub-Saharan Africa, are not well characterized. We investigated the prevalence of impaired glucose metabolism among children and adolescents living with perinatally infected HIV in Ghana. METHODS: In this multicentre, cross-sectional study, we recruited participants from 10 paediatric antiretroviral treatment clinics from January to June 2022 in 10 facilities in Greater Accra and Eastern regions of Ghana. We determined impaired glucose metabolism in the study sample by assessing fasting blood sugar (FBS), insulin resistance as defined by the homeostatic model assessment for insulin resistance (HOMA-IR) index and glycated haemoglobin (HbA1c) levels. The prevalence of impaired glucose metabolism using each criterion was stratified by age and sex. The phenotypic correlates of glucose metabolism markers were also assessed among age, sex, body mass index (BMI) and waist-to-hip ratio (WHR). RESULTS: We analysed data from 393 children and adolescents living with HIV aged 6-18 years. A little over half (205/393 or 52.25%) of the children were female. The mean age of the participants was 11.60 years (SD = 3.50), with 122/393 (31.00%) aged 6-9 years, 207/393 (52.67%) aged 10-15 years, and 62/393 (15.78%) aged 16-18 years. The prevalence rates of glucose impairment in the study population were 15.52% [95% confidence interval (CI): 12.26-19.45], 22.39% (95% CI: 18.54-26.78), and 26.21% (95% CI: 22.10-30.78) using HbA1c, HOMA-IR, and FBS criteria, respectively. Impaired glucose metabolism detected by FBS and HOMA-IR was higher in the older age group, whereas the prevalence of abnormal HbA1c levels was highest among the youngest age group. Age and BMI were positively associated with FBS and HOMA-IR (p < 0.001). However, there was negative correlation of WHR with HOMA-IR (p < 0.01) and HbA1c (p = 0.01). CONCLUSION: The high prevalence of impaired glucose metabolism observed among the children and adolescents living with HIV in sub-Saharan Africa is of concern as this could contribute to the development of metabolic syndrome in adulthood.


Asunto(s)
Glucemia , Infecciones por VIH , Resistencia a la Insulina , Humanos , Adolescente , Femenino , Masculino , Infecciones por VIH/epidemiología , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/complicaciones , Niño , Ghana/epidemiología , Estudios Transversales , Prevalencia , Glucemia/metabolismo , Glucemia/análisis , Índice de Masa Corporal , Hemoglobina Glucada/análisis , Hemoglobina Glucada/metabolismo , Trastornos del Metabolismo de la Glucosa/epidemiología
14.
BMC Microbiol ; 24(1): 163, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38745280

RESUMEN

Spontaneous fermentation of cereals like millet involves a diverse population of microbes from various sources, including raw materials, processing equipment, fermenting receptacles, and the environment. Here, we present data on the predominant microbial species and their succession at each stage of the Hausa koko production process from five regions of Ghana. The isolates were enumerated using selective media, purified, and phenotypically characterised. The LAB isolates were further characterised by 16S rRNA Sanger sequencing, typed using (GTG)5 repetitive-PCR, and whole genome sequencing, while 28S rRNA Sanger sequencing was performed for yeast identification. The pH of the millet grains ranged from mean values of 6.02-6.53 to 3.51-3.99 in the final product, depending on the processors. The mean LAB and yeast counts increased during fermentation then fell to final counts of log 2.77-3.95 CFU/g for LAB and log 2.10-2.98 CFU/g for yeast in Hausa koko samples. At the various processing stages, the counts of LAB and yeast revealed significant variations (p < 0.0001). The species of LAB identified in this study were Limosilactobacillus pontis, Pediococcus acidilactici, Limosilactobacillus fermentum, Limosilactobacillus reuteri, Pediococcus pentosaceus, Lacticaseibacillus paracasei, Lactiplantibacillus plantarum, Schleiferilactobacillus harbinensis, and Weissella confusa. The yeasts were Saccharomyces cf. cerevisiae/paradoxus, Saccharomyces cerevisiae, Pichia kudriavzevii, Clavispora lusitaniae and Candida tropicalis. The identification and sequencing of these novel isolates and how they change during the fermentation process will pave the way for future controlled fermentation, safer starter cultures, and identifying optimal stages for starter culture addition or nutritional interventions. These LAB and yeast species are linked to many indigenous African fermented foods, potentially acting as probiotics in some cases. This result serves as the basis for further studies into the technological and probiotic potential of these Hausa koko microorganisms.


Asunto(s)
Fermentación , Alimentos Fermentados , Microbiología de Alimentos , Mijos , Levaduras , Ghana , Levaduras/clasificación , Levaduras/aislamiento & purificación , Levaduras/genética , Levaduras/metabolismo , Alimentos Fermentados/microbiología , Mijos/microbiología , Lactobacillales/clasificación , Lactobacillales/aislamiento & purificación , Lactobacillales/genética , Lactobacillales/metabolismo , ARN Ribosómico 16S/genética , Filogenia , Concentración de Iones de Hidrógeno , Grano Comestible/microbiología
15.
BMC Microbiol ; 24(1): 250, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38978012

RESUMEN

BACKGROUND: ESBL-producing Escherichia coli pose a growing health risk in community and healthcare settings. We investigated the resistome, virulome, mobilome, and genetic relatedness of multidrug-resistant (MDR) E. coli isolates from patients and their environment in a Ghanaian teaching hospital. MATERIALS AND METHODS: Twenty-three MDR ESBL-producing or carbapenem-resistant E. coli isolates from a collection of MDR Gram-negative bacteria (GNB) from patients and environments were selected for genomic analyses. Whole genome sequencing and bioinformatics tools were used to analyze genomic characteristics and phylogeny. RESULTS: The prevalence and incidence of rectal carriage of ESBL E. coli among patients were 13.65% and 11.32% respectively. The ß-lactamase genes, blaTEM-1B (10 isolates) and blaCTX-M-15 (12 isolates) were commonly associated with IncFIB plasmid replicons and co-occurred with aminoglycoside, macrolide, and sulfamethoxazole/trimethoprim resistance. Insertion sequences, transposons, and class I integrons were found with blaCTX-M-15. Carriage and environmental isolates carried multiple virulence genes, with terC being the most prevalent in 21 isolates. Seventeen sequence types (STs) were identified, including a novel ST (ST13846). Phylogenetic analysis grouped the isolates into four main clusters, with one outlier. High genetic relatedness was observed between two carriage isolates of ST940 and between a carriage isolate and an environmental isolate of ST648. Isolates with different STs, collected at different times and locations, also showed genetic similarities. CONCLUSION: We identified ESBL-producing E. coli with diverse genomic characteristics circulating in different hospital directorates. Clonal relatedness was observed among isolates from patients and the environment, as well as between different patients, suggesting transmission within and between sources.


Asunto(s)
Antibacterianos , Farmacorresistencia Bacteriana Múltiple , Infecciones por Escherichia coli , Escherichia coli , Hospitales de Enseñanza , Filogenia , beta-Lactamasas , Humanos , Ghana/epidemiología , Escherichia coli/genética , Escherichia coli/efectos de los fármacos , Escherichia coli/aislamiento & purificación , Escherichia coli/clasificación , beta-Lactamasas/genética , Farmacorresistencia Bacteriana Múltiple/genética , Infecciones por Escherichia coli/microbiología , Infecciones por Escherichia coli/epidemiología , Antibacterianos/farmacología , Secuenciación Completa del Genoma , Plásmidos/genética , Pruebas de Sensibilidad Microbiana , Genoma Bacteriano/genética , Genómica , Factores de Virulencia/genética , Masculino , Femenino , Adulto
16.
Mol Ecol ; 33(11): e17357, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38683054

RESUMEN

We present a framework for identifying when conditions are favourable for transmission of vector-borne diseases between communities by incorporating predicted disease prevalence mapping with landscape analysis of sociological, environmental and host/parasite genetic data. We explored the relationship between environmental features and gene flow of a filarial parasite of humans, Onchocerca volvulus, and its vector, blackflies in the genus Simulium. We generated a baseline microfilarial prevalence map from point estimates from 47 locations in the ecological transition separating the savannah and forest in Ghana, where transmission of O. volvulus persists despite onchocerciasis control efforts. We generated movement suitability maps based on environmental correlates with mitochondrial population structure of 164 parasites from 15 communities and 93 vectors from only four sampling sites, and compared these to the baseline prevalence map. Parasite genetic distance between sampling locations was significantly associated with elevation (r = .793, p = .005) and soil moisture (r = .507, p = .002), while vector genetic distance was associated with soil moisture (r = .788, p = .0417) and precipitation (r = .835, p = .0417). The correlation between baseline prevalence and parasite resistance surface maps was stronger than that between prevalence and vector resistance surface maps. The centre of the study area had high prevalence and suitability for parasite and vector gene flow, potentially contributing to persistent transmission and suggesting the importance of re-evaluating transmission zone boundaries. With suitably dense sampling, this framework can help delineate transmission zones for onchocerciasis and would be translatable to other vector-borne diseases.


Asunto(s)
Flujo Génico , Insectos Vectores , Onchocerca volvulus , Oncocercosis , Simuliidae , Animales , Oncocercosis/transmisión , Oncocercosis/epidemiología , Insectos Vectores/genética , Insectos Vectores/parasitología , Simuliidae/genética , Simuliidae/parasitología , Humanos , Ghana/epidemiología , Onchocerca volvulus/genética , Prevalencia , Genética de Población , Ambiente
17.
Reprod Biol Endocrinol ; 22(1): 131, 2024 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-39468518

RESUMEN

BACKGROUND: Assisted Reproductive Techniques (ART) have significantly advanced infertility treatment worldwide. However their availability and use in sub-Saharan Africa, remains limited although infertility is highly prevalent, with significant psycho-social challenges including stigma. This study assessed the awareness, attitudes, and perceptions of ART among non-medical tertiary students in Ghana. METHOD: A cross-sectional study was conducted among non-medical students in tertiary institutions in Ghana. Pre-tested questionnaires were administered to both post-graduate and undergraduate students after obtaining informed consent. Ethical approval was obtained from the Review Board at Community Health Department of the University of Ghana Medical School. The data collected was analyzed using SPSS (version-27) and the results presented using frequency tables, graphs, and charts. significance was P-value below 0.05 was considered statistically significant. RESULTS: Overall, 196 participants from the two largest universities and other tertiary institutions in Ghana took part in this study. Majority (63.5%) of respondents demonstrated awareness on ART services, but 60.3% showed poor knowledge of the types of ART. Males generally exhibited lower knowledge of ART services compared to females, and knowledge of ART services showed an inverse relationship with age. In-vitro fertilization (IVF) was the most widely recognized and recommended ART technique, known by 65.1% of respondents who were aware of the types of ART. Most participants expressed reluctance to accept or recommend gamete donation due to religious reasons, fear of complications, and a preference for conventional means of procreation. CONCLUSION: The majority of tertiary students in Ghana are aware of ART for infertility treatment however, many are hesitant toward donor-gamete treatment protocols. Fear of complications and related costs pose major barriers to considering ART among the respondents. Participants unanimously suggested government subsidies and the inclusion of ART under the national health insurance coverage package.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Técnicas Reproductivas Asistidas , Estudiantes , Humanos , Femenino , Técnicas Reproductivas Asistidas/psicología , Masculino , Estudios Transversales , Ghana , Adulto , Adulto Joven , Estudiantes/psicología , Encuestas y Cuestionarios , Concienciación , Aceptación de la Atención de Salud/psicología , Aceptación de la Atención de Salud/estadística & datos numéricos , Adolescente , Universidades
18.
BMC Cancer ; 24(1): 920, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39080553

RESUMEN

BACKGROUND: The two major causes of cancer-related deaths among women in Ghana are breast cancer (BC) and cervical cancer (CC). These types of cancers typically do not show any symptoms until they have progressed. Therefore, it is important to screen for early detection. This research aimed to investigate the rate of breast cancer and cervical cancer screening, as well as the factors associated with it, among women of reproductive age in Ghana. METHODS: This study analysed data from the 2022 Ghana Demographic and Health Survey. A total of 15,014 women aged 15 to 49 years were included in the analysis. Descriptive statistics and binary logistic regression were employed to analyse the data with the aid of STATA/SE, version 17. RESULTS: It was found that 18.4% and 5.0% of the women had screened for BC and CC, respectively. Women aged 45-49 years were about three times more likely (aOR = 2.83, 95% CI: 1.88-4.24) to screen for BC compared to those aged 15-19 years. Women who had tested for HIV had increased odds (aOR = 1.88, 95% CI: 1.56-2.25) of screening for BC compared to their counterparts. Women within the richest wealth index (aOR = 1.95, 95% CI: 1.40-2.72) had increased odds of screening for BC compared to those in the poorest wealth index. Regarding CC screening, women with higher education (aOR = 2.56, 95% CI: 1.53-4.29) were two times more likely to screen for CC compared to those with no formal education. Women who did not use tobacco (aOR = 0.45, 95% CI: 0.21-0.96) had decreased odds of CC screening compared to their counterparts. CONCLUSIONS: This study showed that the uptake of BC and CC screening services among women in Ghana was very low. The drivers of BC and CC screening included enabling, predisposing, and need factors. Stakeholders can leverage the mass media to raise awareness and educate women in reproductive age about the importance of BC and CC screening. This study provides relevant information that can inform BC and CC policies and programmes in Ghana.


Asunto(s)
Neoplasias de la Mama , Detección Precoz del Cáncer , Encuestas Epidemiológicas , Neoplasias del Cuello Uterino , Humanos , Femenino , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/epidemiología , Adulto , Ghana/epidemiología , Persona de Mediana Edad , Detección Precoz del Cáncer/estadística & datos numéricos , Adolescente , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/diagnóstico , Adulto Joven , Tamizaje Masivo/estadística & datos numéricos , Factores Socioeconómicos
19.
Trop Med Int Health ; 29(6): 477-488, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38599337

RESUMEN

INTRODUCTION: Scabies is an underdiagnosed skin infestation caused by the Sarcoptes scabiei mite. The infection causes severe itching and a skin rash but can be effectively treated using topical or systemic drugs. Scabies outbreaks are commonly reported in resource-poor countries, including Ghana. Traditional healers play an important role in primary care in rural areas. The role of these traditional healers in the management of scabies has so far not been explored. The aim of this study was therefore to investigate the perceptions of traditional healers regarding the causation and management of scabies. METHODS: A phenomenological qualitative approach was employed. Traditional healers in the Asante Akim North and Central districts in Ghana were approached with an interview request. Using a semi-structured interview protocol, 15 traditional healers were interviewed. The results were coded and analysed, after which seven themes were extrapolated. RESULTS: Scabies infections were frequently reported by traditional healers. Itching and skin rash were unanimously regarded as the major symptoms of scabies. The majority acknowledged the infectious nature of scabies, but no participant reported the causative organism. A dichotomous disease classification was noted, consisting of 'natural' and 'spiritual' variants each with a unique disease profile and management requirements, as reported by the traditional healers. All but two traditional healers reported to treat scabies using almost exclusively herbs and spiritual rituals. CONCLUSION: The majority of traditional healers were open to collaboration with allopathic healthcare providers. Collaboration could broaden the primary care network in rural areas, but mistrust and lack of transparency form potential barriers to collaboration. We, therefore, emphasise the need for additional efforts to investigate strategies for future collaboration.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Medicinas Tradicionales Africanas , Escabiosis , Escabiosis/tratamiento farmacológico , Humanos , Ghana , Femenino , Masculino , Adulto , Persona de Mediana Edad , Investigación Cualitativa , Animales , Entrevistas como Asunto , Percepción , Practicantes de la Medicina Tradicional
20.
Trop Med Int Health ; 29(3): 206-213, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38093593

RESUMEN

BACKGROUND: Healthcare resources are often limited in areas of sub-Saharan Africa. This makes accurate and timely diagnoses challenging and delays treatment of childhood febrile illness. We explored longitudinal characteristics related to symptoms, diagnosis and treatment of hospitalised febrile children in a rural area of Ghana highly endemic for malaria. METHODS: Febrile children under 15 years, admitted to the study hospital paediatric ward, were recruited to the study and clinical data were collected throughout hospitalisation. Descriptive statistics were reported for all cases; for longitudinal analyses, a subset of visits with limited missing data was used. RESULTS: There were 801 hospitalised children included in longitudinal analyses. Malaria (n = 581, 73%) and sepsis (n = 373, 47%) were the most prevalent suspected diagnoses on admission. One-third of malaria suspected diagnoses (n = 192, 33%) were changed on the discharge diagnosis, compared to 84% (n = 315) of sepsis suspected diagnoses. Among malaria-only discharge diagnoses, 98% (n/N = 202/207) received an antimalarial and 33% (n/N = 69/207) an antibiotic; among discharge diagnoses without malaria, 28% (n/N = 108/389) received an antimalarial and 83% (n/N = 324/389) an antibiotic. CONCLUSIONS: Suspected diagnoses were largely based on clinical presentation and were frequently changed; changed diagnoses were associated with lingering symptoms, underscoring the need for faster and more accurate diagnostics. Medications were over-prescribed regardless of diagnosis stability, possibly because of a lack of confidence in suspected diagnoses. Thus, better diagnostic tools are needed for childhood febrile illnesses to enhance the accuracy of and confidence in diagnoses, and to cut down unjustified medication use, reducing the risk of antimicrobial and malaria resistance.


Asunto(s)
Antimaláricos , Malaria , Sepsis , Niño , Humanos , Lactante , Antimaláricos/uso terapéutico , Ghana/epidemiología , Fiebre/diagnóstico , Fiebre/etiología , Fiebre/tratamiento farmacológico , Malaria/diagnóstico , Malaria/tratamiento farmacológico , Malaria/epidemiología , Antibacterianos/uso terapéutico , Hospitales , Sepsis/diagnóstico , Sepsis/tratamiento farmacológico , Sepsis/epidemiología
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