207 research outputs found
Management of childhood infections in rural Ghana - Filling information gaps
Many low-income countries are facing high childhood morbidity and mortality rates. Especially in sub-Saharan Africa and Asia, infectious diseases are the predominant cause of disability-adjusted life years in children. Hence, several national and international health institutions prioritise childhood infectious disease control. However, the success of these control efforts differs between, as well as within nations, highlighting the relevance of local implementation challenges. The aim of this thesis was to provide missing information for childhood infectious disease management in Ghana, with a special focus on the Ashanti Region, and to present these results within the context of available public health data. A conceptual research framework (CRF) was established, which defines data needed to inform childhood infectious disease control. The CRF comprises the components (i) population, (ii) health system, (iii) health services, (iv) disease data, (v) diagnosis and treatment, and (vi) intervention and prevention. The data generated within the frame of the thesis, along with further published documents, were reviewed taking into consideration the objectives posed by the CRF. The thesis demonstrates that Ghana and the Ashanti Region have a well-planned childhood infectious disease management system. Priorities in childhood infectious disease control are identified and formulated into health policies. Various disease-specific interventions are in place to control disease transmission. Furthermore, the organisation of preventive and curative services emphasises childhood infectious disease control. However, implementation challenges constrain successful delivery of health services at all administrative levels. Shortage of medical equipment and health care personnel hamper health service provision, especially in rural areas. Generally, poor people living in remote areas are disadvantaged in several ways they are more likely to be affected by resource constraints, they utilise health services less often, and they are at higher risk of contracting several diseases. Ghana has designed effective disease control programmes, which explicitly prioritise the poor and people living in remote areas. However, resource gaps as well as administrative barriers limit successful delivery of these measures. This thesis shows that no additional health programmes are needed to improve childhood infectious disease management, but the government needs to overcome obstacles identified at all administrative levels in order to successfully deliver established health services to the whole population
The Causal Effect of Malaria on Stunting: A Mendelian Randomization and Matching Approach
Background Previous studies on the association of malaria and stunted growth delivered inconsistent results. These conflicting results may be due to different levels of confounding and to considerable difficulties in elucidating a causal relationship. Randomized experiments are impractical and previous observational studies have not fully controlled for potential confounding including nutritional deficiencies, breastfeeding habits, other infectious diseases and socioeconomic status. Methods This study aims to estimate the causal effect between malaria episodes and stunted growth by applying a combination of Mendelian randomization, using the sickle cell trait, and matching. We demonstrate the method on a cohort of children in the Ashanti Region, Ghana. Results We found that the risk of stunting increases by 0.32 (P-value: 0.004, 95% CI: 0.09, 1.0) for every malaria episode. The risk estimate based on Mendelian randomization substantially differs from the multiple regression estimate of 0.02 (P-value: 0.02, 95% CI: 0.003, 0.03). In addition, based on the sensitivity analysis, our results were reasonably insensitive to unmeasured confounders. Conclusions The method applied in this study indicates a causal relationship between malaria and stunting in young children in an area of high endemicity and demonstrates the usefulness of the sickle cell trait as an instrument for the analysis of conditions that might be causally related to malaria
Feasibility of Electronic Health Information and Surveillance System (eHISS) for disease symptom monitoring: A case of rural Ghana.
The current surge of mobile phone use in many African countries creates the opportunity to provide caregivers with limited access to the health care system with vital health recommendations. At the same time such communication system can be utilised to collect tempero-spatial data on disease symptoms
a cross-sectional study on the association between urbanicity and the acquisition of immunity
Background Malaria incidence has declined considerably over the last decade.
This is partly due to a scale-up of control measures but is also attributed to
increasing urbanization. This study aimed to analyse the association between
malaria and urbanization and the effect of urbanicity on the acquisition of
semi-immunity. Methods In 2012, children with fever presenting to St Michaelâs
Hospital Pramso/Ghana were recruited. The malaria-positive-fraction (MPF) of
fever cases was calculated on community-level to approximate the malaria risk.
The mean age of malaria cases was calculated for each community to estimate
the acquisition of semi-immunity. The level of urbanicity for the communities
was calculated and associations between MPF, urbanicity and immunity were
modelled using linear regression. Results Twenty-six villages were included
into the study with a mean MPF of 35 %. A linear decrease of 5 % (95 % CI: 4â6
%) in MPF with every ten-point increase in urbanicity was identified. The mean
age of malaria patients increased by 2.9 months (95 % CI: 1.0â4.8) with every
ten-point increase in urbanicity. Discussion The results confirm an
association between an increase in urbanicity and declining malaria risk and
demonstrate that the acquisition of semi-immunity is heterogeneous on a micro-
epidemiological scale and is associated with urbanicity
Associations between eight earth observation-derived climate variables and enteropathogen infection: An independent participant data meta-analysis of surveillance studies with broad spectrum nucleic acid diagnostics
Diarrheal disease, still a major cause of childhood illness, is caused by numerous, diverse infectious microorganisms, which are differentially sensitive to environmental conditions. Enteropathogenâspecific impacts of climate remain underexplored. Results from 15 studies that diagnosed enteropathogens in 64,788 stool samples from 20,760 children in 19 countries were combined. Infection status for 10 common enteropathogensâadenovirus, astrovirus, norovirus, rotavirus, sapovirus, Campylobacter, ETEC, Shigella, Cryptosporidium and Giardiaâwas matched by date with hydrometeorological variables from a global Earth observation datasetâprecipitation and runoff volume, humidity, soil moisture, solar radiation, air pressure, temperature, and wind speed. Models were fitted for each pathogen, accounting for lags, nonlinearity, confounders, and threshold effects. Different variables showed complex, nonâlinear associations with infection risk varying in magnitude and direction depending on pathogen species. Rotavirus infection decreased markedly following increasing 7âday average temperaturesâa relative risk of 0.76 (95% confidence interval: 0.69â0.85) above 28°Câwhile ETEC risk increased by almost half, 1.43 (1.36â1.50), in the 20â35°C range. Risk for all pathogens was highest following soil moistures in the upper range. Humidity was associated with increases in bacterial infections and decreases in most viral infections. Several virus species\u27 risk increased following lowerâthanâaverage rainfall, while rotavirus and ETEC increased with heavier runoff. Temperature, soil moisture, and humidity are particularly influential parameters across all enteropathogens, likely impacting pathogen survival outside the host. Precipitation and runoff have divergent associations with different enteric viruses. These effects may engender shifts in the relative burden of diarrheaâcausing agents as the global climate changes
Detection and Characterization of ESBL-Producing Escherichia coli From Humans and Poultry in Ghana
Introduction: The increasing incidence of infections caused by extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli in sub-Saharan Africa is of serious concern. Studies from countries with a highly industrialized poultry industry suggest the poultry production-food-consumer chain as a potential transmission route. In Africa, integrated studies at this humanâanimal interface are still missing.Aim: To determine the molecular epidemiology of ESBL-producing E. coli from the intestinal tract of humans and poultry in rural Ghana.Methods: During a 6-month period, fecal samples from all children admitted to the Agogo Hospital (Ghana) and broilers at eight poultry farms located within the hospital catchment area were collected. After screening on selective ESBL agar, whole genome sequencing (WGS) was performed on all ESBL isolates. The genomes were analyzed using multilocus sequence typing (MLST), ESBL genotyping and genome-based phylogenetic analyses.Results: Of 140 broilers and 54 children, 41 (29%) and 33 (61%) harbored ESBL E. coli, respectively, with prevalences on farms ranging between 0 and 85%. No predominant sequence type (ST) was detected among humans. ST10 was most prevalent among broilers (n = 31, 69%). The ESBL gene blaCTX-M-15 was predominant among broilers (n = 43, 96%) and humans (n = 32, 97%). Whole-genome-based phylogenetic analysis revealed three very closely related broiler/human isolate clusters (10% of ESBL isolates) with chromosomal and plasmid-mediated ESBL genes.Conclusion: The findings demonstrate a high frequency of intestinal ESBL-producing E. coli in rural Ghana. Considering that animal and human samples are independent specimens from the same geographic location, the number of closely related ESBL isolates circulating across these two reservoirs is substantial. Hence, poultry farms or meat products might be an important source for ESBL-producing bacteria in rural Ghana leading to difficult-to-treat infections in humans
Characterization of Salmonella enterica from invasive bloodstream infections and water sources in rural Ghana.
BACKGROUND: Non-typhoidal Salmonella (NTS) cause the majority of bloodstream infections in Ghana, however the mode of transmission and source of invasive NTS in Africa are poorly understood. This study compares NTS from water sources and invasive bloodstream infections in rural Ghana. METHODS: Blood from hospitalised, febrile children and samples from drinking water sources were analysed for Salmonella spp. Strains were serotyped to trace possible epidemiological links between human and water-derived isolates.. Antibiotic susceptibility testing was performed, RESULTS: In 2720 blood culture samples, 165 (6%) NTS were isolated. S. Typhimurium (70%) was the most common serovar followed by S. Enteritidis (8%) and S. Dublin (8%). Multidrug resistance (MDR) was found in 95 (58%) NTS isolates, including five S. Enteritidis. One S. Typhimurium showed reduced fluroquinolone susceptibility. In 511 water samples, 19 (4%) tested positive for S. enterica with two isolates being resistant to ampicillin and one isolate being resistant to cotrimoxazole. Serovars from water samples were not encountered in any of the clinical specimens. CONCLUSION: Water analyses demonstrated that common drinking water sources were contaminated with S. enterica posing a potential risk for transmission. However, a link between S. enterica from water sources and patients could not be established, questioning the ability of water-derived serovars to cause invasive bloodstream infections
Health System Resource Gaps and Associated Mortality from Pandemic Influenza across Six Asian Territories
BACKGROUND: Southeast Asia has been the focus of considerable investment in pandemic influenza preparedness. Given the wide variation in socio-economic conditions, health system capacity across the region is likely to impact to varying degrees on pandemic mitigation operations. We aimed to estimate and compare the resource gaps, and potential mortalities associated with those gaps, for responding to pandemic influenza within and between six territories in Asia. METHODS AND FINDINGS: We collected health system resource data from Cambodia, Indonesia (Jakarta and Bali), Lao PDR, Taiwan, Thailand and Vietnam. We applied a mathematical transmission model to simulate a "mild-to-moderate" pandemic influenza scenario to estimate resource needs, gaps, and attributable mortalities at province level within each territory. The results show that wide variations exist in resource capacities between and within the six territories, with substantial mortalities predicted as a result of resource gaps (referred to here as "avoidable" mortalities), particularly in poorer areas. Severe nationwide shortages of mechanical ventilators were estimated to be a major cause of avoidable mortalities in all territories except Taiwan. Other resources (oseltamivir, hospital beds and human resources) are inequitably distributed within countries. Estimates of resource gaps and avoidable mortalities were highly sensitive to model parameters defining the transmissibility and clinical severity of the pandemic scenario. However, geographic patterns observed within and across territories remained similar for the range of parameter values explored. CONCLUSIONS: The findings have important implications for where (both geographically and in terms of which resource types) investment is most needed, and the potential impact of resource mobilization for mitigating the disease burden of an influenza pandemic. Effective mobilization of resources across administrative boundaries could go some way towards minimizing avoidable deaths
Transcriptomic signatures differentiate survival from fatal outcomes in humans infected with Ebola virus
Background In 2014, Western Africa experienced an unanticipated explosion of Ebola virus infections. What distinguishes fatal from non-fatal outcomes remains largely unknown, yet is key to optimising personalised treatment strategies. We used transcriptome data for peripheral blood taken from infected and convalescent recovering patients to identify early stage host factors that are associated with acute illness and those that differentiate patient survival from fatality. Results The data demonstrate that individuals who succumbed to the disease show stronger upregulation of interferon signalling and acute phase responses compared to survivors during the acute phase of infection. Particularly notable is the strong upregulation of albumin and fibrinogen genes, which suggest significant liver pathology. Cell subtype prediction using messenger RNA expression patterns indicated that NK-cell populations increase in patients who survive infection. By selecting genes whose expression properties discriminated between fatal cases and survivors, we identify a small panel of responding genes that act as strong predictors of patient outcome, independent of viral load. Conclusions Transcriptomic analysis of the host response to pathogen infection using blood samples taken during an outbreak situation can provide multiple levels of information on both disease state and mechanisms of pathogenesis. Host biomarkers were identified that provide high predictive value under conditions where other predictors, such as viral load, are poor prognostic indicators. The data suggested that rapid analysis of the host response to infection in an outbreak situation can provide valuable information to guide an understanding of disease outcome and mechanisms of disease
- âŚ