Kwabena O. Duedu

Chronic noncommunicable diseases in 6 low- and middle-income countries: Findings from wave 1 of the world health organization's Study on Global Ageing and Adult Health (SAGE)

In this paper, we examine patterns of self-reported diagnosis of noncommunicable diseases (NCDs) and prevalences of algorithm/measured test-based, undiagnosed, and untreated NCDs in China, Ghana, India, Mexico, Russia, and South Africa. Nationally representative samples of older adults aged ≥50 years were analyzed from wave 1 of the World Health Organizations Study on Global Ageing and Adult Health (2007-2010; n = 34,149). Analyses focused on 6 conditions: angina, arthritis, asthma, chronic lung disease, depression, and hypertension. Outcomes for these NCDs were: 1) self-reported disease, 2) algorithm/measured test-based disease, 3) undiagnosed disease, and 4) untreated disease. Algorithm/measured test-based prevalence of NCDs was much higher than self-reported prevalence in all 6 countries, indicating underestimation of NCD prevalence in low- and middle-income countries. Undiagnosed prevalence of NCDs was highest for hypertension, ranging from 19.7% (95% confidence interval (CI): 18.1, 21.3) in India to 49.6% (95% CI: 46.2, 53.0) in South Africa. The proportion untreated among all diseases was highest for depression, ranging from 69.5% (95% CI: 57.1, 81.9) in South Africa to 93.2% (95% CI: 90.1, 95.7) in India. Higher levels of education and wealth significantly reduced the odds of an undiagnosed condition and untreated morbidity. A high prevalence of undiagnosed NCDs and an even higher proportion of untreated NCDs highlights the inadequacies in diagnosis and management of NCDs in local health-care systems.

A comparative survey of the prevalence of human parasites found in fresh vegetables sold in supermarkets and open-aired markets in Accra, Ghana

BackgroundConsuming raw vegetables offers essential nutrients that one may not get when such vegetables are usually cooked. However, eating them raw may pose a great risk for transmissions of pathogens. Such risks may be influenced by the sources of the vegetables and washing techniques used. The aim of the study was to compare the prevalence and diversity of parasitic pathogens associated with vegetables sold at the two types of markets in Ghana and compare effectiveness of various washing techniques.MethodsWe purchased two batches of samples of cabbage, sweet bell pepper, carrot, lettuce, tomato and onion within a two week interval. The vegetables were washed by three methods and the wash solution was concentrated and analyzed for parasites.ResultsThe prevalent parasites detected were Strongyloides stercoralis larvae (43%) and Cryptosporidium parvum oocyst (16%). Others present were Hookworm ova, Entamoeba histolytica cysts, Giardia lamblia cysts, Cyclospora cayetanensis oocysts, Entamoeba coli cysts, Trichuris trichiuria ova, Enterobius vermicularis ova, Isospora belli oocysts and Fasciolopsis buski ova. Contamination was highest in lettuce (61%) and cabbage and the least contaminated was tomato (18%). Contamination of vegetables sold at the open-aired markets was about ten-times that of the supermarkets.ConclusionsIn Ghana, the large open-aired markets are the most patronized and serve as a supply point for most corner shops and stalls. The results thus highlight the potential of fresh vegetables serving as a major source of food-borne disease outbreaks and the contribution of open-aired markets to their transmission. Urgent public education on handling of fresh vegetables is recommended.

A survey of pathogens associated with Cyperus esculentus L (tiger nuts) tubers sold in a Ghanaian city.

BackgroundCyperus esculentus L, is a minor but important crop in Ghana. They are noted mostly by their aphrodisiac properties among others. The nuts are often eaten raw as an unprocessed snack due to its rich flavour and texture. Though eaten raw, the nuts are sometimes handled unhygienically, posing a public health threat. This study therefore aimed at determining the level and distribution of parasitic and bacterial contaminants associated with the crop as it is sold.ResultsFour types of intestinal parasites were identified, and the most prevalent was Cryptosporidium parvum (30.0%). Nuts contaminated with parasites were found only among street vendors. Bacteriological examination showed three different groups of bacterial isolates with the most prevalent being coliforms (54.2%). Unlike parasites, bacteria isolates were found among samples from both street vendors and market places. Multiple drug resistance was displayed by Proteus vulgaris.ConclusionsBuying and eating nuts as well as other fruits taken raw from street vendors and market places could pose a significant public health threat. There is a need for efficient monitoring systems for food borne pathogens in Ghana.

Microbial Carriage of Cockroaches at a Tertiary Care Hospital in Ghana

Cockroaches are common in the environment of many hospitals in Ghana; however, little is known about their public health risks. To evaluate potential risks, we investigated the external and internal microbial flora of 61 cockroaches from a tertiary hospital in Ghana and evaluated the antibiotic resistance profiles of the common bacterial species. Standard methods were used in all the microbiological investigations and antibiotic susceptibility testing. A rotavirus carriage rate of 19.7% was observed among the cockroaches. Four types of intestinal parasites were carried externally by the cockroaches, and the most prevalent was Hookworm (4.9%). Eight nosocomial bacteria were isolated from the cockroaches, and the most prevalent was Klebsiella pneumoniae, which occurred internally in 29.5% of the cockroaches and 26.2% externally. Multiple drug resistance among common bacteria isolated from the cockroaches ranged from 13.8% (Escherichia coli) to 41.1% (Klebsiella pneumoniae). Cockroaches constitute an important reservoir for pathogenic microorganisms, and may be important vectors of multiple resistant nosocomial pathogens in the studied hospital.

The effects of co-infection with human parvovirus B19 and Plasmodium falciparum on type and degree of anaemia in Ghanaian children

OBJECTIVE To determin the extent to which parvovirus B19 (B19V) and co-infection of B19V and malaria contribute to risk of anaemia in children. METHODS B19V DNA and malaria parasites were screened for 234 children at the PML Childrens Hospital in Accra. The role of B19V and co-infection with B19V and malaria in anaemia was evaluated by analysing full blood cell counts, malaria and B19V DNA results from these children. RESULTS The prevalence of B19V, malaria and co-infection with B19V and malaria was 4.7%, 41.9% and 2.6%, respectively. Malaria posed a greater risk in the development of mild anaemia compared to severe anaemia (OR=5.28 vrs 3.15) whereas B19V posed a higher risk in the development of severe anaemia compared to mild anaemia (OR=4.07 vrs 1.00) from a non-anaemic child. Persons with co-infection with B19V and malaria had 2.23 times the risk (95% CI=0.40-12.54) of developing severe anaemia should they already have a mild anaemia. The degree of anaemia was about three times affected by co-infection (Pillais trace=0.551, P=0.001) as was affected by malaria alone (Pillais trace=0.185, P=0.001). B19V alone did not significantly affect the development of anaemia in a non-anaemic child. Microcytic anaemia was associated with B19V and co-infection with B19V and malaria more than normocytic normochromic anaemia. CONCLUSIONS B19V was associated with malaria in cases of severe anaemia. The association posed a significant risk for exacerbation of anaemia in mild anaemic children. B19V and co-infection with B19V and malaria may be associated with microcytic anaemia rather than normocytic normochromic anaemia as seen in cases of B19V infection among persons with red cell abnormalities.

Two-colour fluorescence fluorimetric analysis for direct quantification of bacteria and its application in monitoring bacterial growth in cellulose degradation systems

Monitoring bacterial growth is an important technique required for many applications such as testing bacteria against compounds (e.g. drugs), evaluating bacterial composition in the environment (e.g. sewage and wastewater or food suspensions) and testing engineered bacteria for various functions (e.g. cellulose degradation). T?=1,^FigItem(1) ^ReloadFigure=Yesraditionally, rapid estimation of bacterial growth is performed using spectrophotometric measurement at 600nm (OD600) but this estimation does not differentiate live and dead cells or other debris. Colony counting enumerates live cells but the process is laborious and not suitable for large numbers of samples. Enumeration of live bacteria by flow cytometry is a more suitable rapid method with the use of dual staining with SYBR I Green nucleic acid gel stain and Propidium Iodide (SYBR-I/PI). Flow cytometry equipment and maintenance costs however are relatively high and this technique is unavailable in many laboratories that may require a rapid method for evaluating bacteria growth. We therefore sought to adapt and evaluate the SYBR-I/PI technique of enumerating live bacterial cells for a cheaper platform, a fluorimeter. The fluorimetry adapted SYBR-I/PI enumeration of bacteria in turbid growth media had direct correlations with OD600 (p>0.001). To enable comparison of fluorescence results across labs and instruments, a fluorescence intensity standard unit, the equivalent fluorescent DNA (EFD) was proposed, evaluated and found useful. The technique was further evaluated for its usefulness in enumerating bacteria in turbid media containing insoluble particles. Reproducible results were obtained which OD600 could not give. An alternative method based on the assessment of total protein using the Pierce Coomassie Plus (Bradford) Assay was also evaluated and compared. In all, the SYBR-I/PI method was found to be the quickest and most reliable. The protocol is potentially useful for high-throughput applications such as monitoring of growth of live bacterial cells in 96-well microplates and in assessing in vivo activity of cellulose degrading enzyme systems.

Prevalence of Intestinal Parasites and Association with Malnutrition at a Ghanaian Orphanage

Parasitic infections particularly neglected tropical diseases affect millions of individuals in sub-Saharan Africa. It is associated with poverty and limited resources, which is a key characteristic of orphanages. Unfortunately, there is very scarce baseline data about the prevalence of parasitic infections within orphanages and other institutions with limited resources and special needs in Ghana. We conducted a cross-sectional survey among 101 inhabitants of one of the major orphanages in Ghana. We collected demographic and anthropological data to assess living conditions as well as nutritional status and how these relate to parasitic infections. Parasitic infections were detected from stool samples collected and analyzed by standard parasitological techniques. The prevalence of parasitic infections was 15.8%. Parasites isolated were Ascaris lumbricoides (5%), Trichuris trichiura (1%), hookworm (1%), Clonorchis sinensis (2%), Fasciola hepatica (2%), Hymenolepis nana (2%), Schistosoma mansoni (3%), Taenia spp. (1%), Strongyloides stercoralis (2%), and Giardia duodenalis (1%). There was a significant association between malnutrition and parasitic infections. The prevalence of intestinal parasites among inmates is high. With the exception of S. stercoralis, which infects via skin penetration, all others have some association with water either drunk or for play. The need for proper evaluation of water supply and its safety is strongly encouraged.

Beyond Genetic Engineering: Technical Capabilities in the Application Fields of Biocatalysis and Biosensors

Synthetic biology allows the generation of complex recombinant systems using libraries of modular components. Two major near-market applications are whole-cell biosensors and biocatalysts for conversion of lignocellulosic biomass to biofuels and chemical feedstocks. Whole cell biosensors consist of cells genetically modified so that binding of a specific analyte to a receptor in the cell triggers generation of a specific output which can be detected and quantified. Since these systems are intrinsically modular in nature, with separate systems for signal detection, signal processing, and generation of the output, they are well suited to a synthetic biology approach. Likewise, effective degradation of cellulosic biomass requires a battery of different enzymes working together to degrade the matrix, expose the polysaccharide fibres, hydrolyse these to release sugars, and convert the sugars to useful products. Synthetic biology provides a useful set of tools to generate such systems. In this chapter we consider how synthetic biology has been applied to these applications, and look at possible future developments in these areas.

Citrobacter freundii as a test platform for recombinant cellulose degradation systems

Cellulosic biomass represents a huge reservoir of renewable carbon, but converting it into useful products is challenging. Attempts to transfer cellulose degradation capability to industrially useful micro‐organisms have met with limited success, possibly due to poorly understood synergy between multiple cellulases. This is best studied by co‐expression of many combinations of cellulases and associated proteins. Here, we describe the development of a test platform based on Citrobacter freundii, a cellobiose‐assimilating organism closely related to Escherichia coli. Standard E. coli cloning vectors worked well in Cit. freundii. Expression of cellulases CenA and Cex of Cellulomonas fimi in Cit. freundii gave recombinant strains which were able to grow at the expense of cellulosic filter paper or microcrystalline cellulose (Avicel) in a mineral medium supplemented with a small amount of yeast extract. Periodic physical agitation of the cultures was highly beneficial for growth at the expense of filter paper. This provides a test platform for the expression of combinations of genes encoding biomass‐degrading enzymes to develop effective genetic cassettes for degradation of different biomass streams.

Multidrug Resistant Enteric Bacterial Pathogens in a Psychiatric Hospital in Ghana: Implications for Control of Nosocomial Infections

Enteric bacteria are commonly implicated in hospital-acquired or nosocomial infections. In Ghana, these infections constitute an important public health problem but little is known about their contribution to antibiotic resistance. The aim of the study was to determine the extent and pattern of antibiotic resistance of enteric bacteria isolated from patients and environmental sources at the Accra Psychiatric Hospital. A total of 265 samples were collected from the study site including 142 stool and 82 urine samples from patients, 7 swab samples of door handle, and 3 samples of drinking water. Enteric bacteria were isolated using standard microbiological methods. Antibiograms of the isolates were determined using the disc diffusion method. Overall, 232 enteric bacteria were isolated. Escherichia coli was the most common (38.3%), followed by Proteus (19.8%), Klebsiella (17.7%), Citrobacter (14.7%), Morganella (8.2%), and Pseudomonas (1.3%). All isolates were resistant to ampicillin but sensitive to cefotaxime. The resistance ranged from 15.5% to 84.5%. Multidrug resistance was most prevalent (100%) among isolates of Proteus and Morganella and least prevalent among isolates of Pseudomonas (33.3%). Multidrug resistance among enteric bacteria at the study hospital is high and hence there is a need for screening before therapy to ensure prudent use of antibiotics.