Papers by Alexander Debrah
PLOS Neglected Tropical Diseases, 2020
Morbidity burden of lymphatic filariasis (LF) relies on the information from the Mass Drug Admini... more Morbidity burden of lymphatic filariasis (LF) relies on the information from the Mass Drug Administration (MDA) programme where Community Health Volunteers (CHVs) passively report cases identified. Consequently, the exact prevalence of morbidity cases is not always accurate. The use of mobile phone technology to report morbidity cases was piloted in Ghana using a text-based short messaging service (SMS) tool by CHVs. Though successful, illiterate CHVs could not effectively use the SMS tool. The aim of this study was to evaluate the use of a mobile phone-based Interactive Voice Response System (mIVRS) by CHVs in reporting LF morbidity cases and acute dermatolymphangioadenitis (ADLA) attacks in Ghana. The mIVRS was designed as a surveillance tool to capture LF data in Kassena Nankana Districts of Ghana. One hundred CHVs were trained to identify and report lymphedema and hydrocele cases as well as ADLA attacks by calling a hotline linked to the mIVRS. The system asked a series of quest...
Bookmarks Related papers MentionsView impact
Infection, Jan 18, 2023
Bookmarks Related papers MentionsView impact
Journal of Inflammation Research, Apr 1, 2021
Bookmarks Related papers MentionsView impact
Journal of Tropical Medicine, Aug 1, 2020
Bookmarks Related papers MentionsView impact
Human Immunology
Bookmarks Related papers MentionsView impact
Infection
Purpose Human tuberculosis is characterized by immunopathology that affects T-cell phenotype and ... more Purpose Human tuberculosis is characterized by immunopathology that affects T-cell phenotype and functions. Previous studies found impaired T-cell response to phytohemagglutinin (PHA) in patients with acute tuberculosis. However, the influence of disease severity, affected T-cell subsets, and underlying mechanisms remain elusive. Methods Here we investigated PHA-induced and antigen-specific T-cell effector cytokines in tuberculosis patients (n = 55) as well as in healthy asymptomatic contacts (n = 32) from Ghana. Effects of Mycobacterium (M.) tuberculosis sputum burden and treatment response were analyzed and compared during follow-up. Finally, cytokine characteristics of the aberrant plasma milieu in tuberculosis were analyzed as a potential cause for impaired PHA response. Results PHA-induced IFN-γ expression was significantly lower in sputum-positive tuberculosis patients as compared to both, contacts and paucibacillary cases, and efficiently discriminated the study groups. T-cel...
Bookmarks Related papers MentionsView impact
Immunology
Monocyte‐derived macrophages contribute centrally to immune protection in Mycobacterium tuberculo... more Monocyte‐derived macrophages contribute centrally to immune protection in Mycobacterium tuberculosis infection and changes in monocyte phenotype characterize immunopathology in tuberculosis patients. Recent studies highlighted an important role of the plasma milieu in tuberculosis immunopathology. Here, we investigated monocyte pathology in patients with acute tuberculosis and determined tuberculosis plasma milieu effects on phenotype as well as cytokine signalling of reference monocytes. Patients with tuberculosis (n = 37) and asymptomatic contacts (controls n = 35) were recruited as part of a hospital‐based study in the Ashanti region of Ghana. Multiplex flow cytometry phenotyping of monocyte immunopathology was performed and effects of individual blood plasma samples on reference monocytes prior to and during treatment were characterized. Concomitantly, cell signalling pathways were analysed to elucidate underlying mechanisms of plasma effects on monocytes. Multiplex flow cytomet...
Bookmarks Related papers MentionsView impact
Vaccines, Apr 17, 2023
Bookmarks Related papers MentionsView impact
BackgroundOnchocerciasis is the world’s second leading cause of infectious blindness and a major ... more BackgroundOnchocerciasis is the world’s second leading cause of infectious blindness and a major public health problem in many parts of the world, including Ghana, with severe impact on the skin also. Mass drug administration (MDA) with ivermectin began in the Sefwi Akontombra district of the Western North Region of Ghana in 1994. The aim of this cross-sectional study was to evaluate the impact of about three decades of MDA on onchocerciasis and its clinical manifestations by investigating the current nodule and microfilaria (MF) prevalence in the Sefwi Akontombra district using established protocols. MethodologyThis cross-sectional study had participants examined for signs of dermal/skin onchocerciasis and palpated, and those with ≥1 palpable sub-cutaneous nodule had skin snips taken from the left and right iliac crests for later parasitological (microfilariae) assessment. Logistic regression models were used to identify independent predictive and risk factors significantly associa...
Bookmarks Related papers MentionsView impact
Infection
Background Mycobacterium (M.) tuberculosis-caused immunopathology is characterized by aberrant ex... more Background Mycobacterium (M.) tuberculosis-caused immunopathology is characterized by aberrant expression of plasma cytokines in human tuberculosis. Disease severity and long-term anti-mycobacterial treatment are potentially influenced by immunopathology and normalization of plasma cytokine levels during therapy may indicate treatment efficacy and recovery. Study design and methods In this study, we analyzed the concentrations of selected plasma cytokines (i.e., IL-6, IP-10, IL-10, IL-22, IFNγ, GM-CSF, IL-8) and M. tuberculosis sputum burden in patients with tuberculosis (n = 76). Cytokine levels were compared to healthy contacts (n = 40) and changes under treatment were monitored (i.e., 6 and 16 weeks after treatment start). According to differences in M. tuberculosis sputum burden and conversion, tuberculosis patients were classified as paucibacillary as well as ‘rapid’ or ‘slow’ treatment responders. A subgroup of tuberculosis patients had fatal disease courses. Results Six of se...
Bookmarks Related papers MentionsView impact
http://isrctn.com/, 2022
Bookmarks Related papers MentionsView impact
Calibration curve of the O-150 qPCR assay. Calibration samples have been analyzed in 4-fold. Geom... more Calibration curve of the O-150 qPCR assay. Calibration samples have been analyzed in 4-fold. Geometric mean and 95% confidence interval are indicated. (PDF 34 kb)
Bookmarks Related papers MentionsView impact
Cq values of actb qPCR assay on the 150 gDNA samples. Mean and standard deviation are indicated, ... more Cq values of actb qPCR assay on the 150 gDNA samples. Mean and standard deviation are indicated, as well as the line indicating meanâ +â 2 standard deviations. The four samples that had Cq values above this cut-off were excluded in further analyses. (PDF 29 kb)
Bookmarks Related papers MentionsView impact
Model of association for filarial lymphedema risk alleles (DOCX 13 kb)
Bookmarks Related papers MentionsView impact
List of genotyped single nucleotide polymorphisms (DOCX 35 kb)
Bookmarks Related papers MentionsView impact
Overnight trap collections for dry season and wet season (6Â pm â 6Â am). (DOCX 67Â kb)
Bookmarks Related papers MentionsView impact
Evening trap and hlc collections (4â 7Â pm) for dry season and wet season. (DOCX 106Â kb)
Bookmarks Related papers MentionsView impact
Demographic sistribution of volunteers in study communities. (DOCX 83Â kb)
Bookmarks Related papers MentionsView impact
Parasites & Vectors, 2016
Bookmarks Related papers MentionsView impact
Parasitology Research, 2008
Bookmarks Related papers MentionsView impact
Uploads
Papers by Alexander Debrah