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Burton H Singer

Publications and source records attributed to Burton H Singer.

At least 37 records · Page 2Linked to original sources
PubMed2004

Representation of authors and editors from countries with different human development indexes in the leading literature on tropical medicine: survey of current evidence.

OBJECTIVE: To assess the current international representation of members of editorial and advisory boards and authors in the leading peer reviewed literature on tropical medicine. DESIGN: Systematic review. MAIN OUTCOME MEASURES: Country affiliations, as classified by the human development index, of editorial and advisory board members of all tropical medicine journals referenced by the Institute of Scientific Information (ISI) as of late 2003 and of all contributing authors of full articles published in the six leading journals on tropical medicine in 2000-2. RESULTS: Sixteen (5.1%) of the 315 editorial and advisory board members from the 12 ISI referenced journals on tropical medicine are affiliated to countries with a low human development index and 223 (70.8%) to countries with a high index. Examination of the 2384 full articles published in 2000-2 in the six highest ranking tropical medicine journals showed that 48.1% of contributing authors are affiliated to countries with a high human development index, whereas the percentage of authors from countries with a low index was 13.7%. Articles written exclusively by authors from low ranked countries accounted for 5.0%. Our data indicate that research collaborations between a country with a high human development index and one that has either a medium or a low index are common and account for 26.5% and 16.1% of all full articles, respectively. CONCLUSION: Current collaborations should be transformed into research partnerships, with the goals of mutual learning and institutional capacity strengthening in the developing world.

Advisory Committees↗
PubMed2004

Opportunities and limiting factors of intensive vegetable farming in malaria endemic Côte d'Ivoire.

Poverty reduction policies guide development strategies. In economies that depend heavily on agriculture, in the face of rapid population growth, innovative approaches are required to satisfy food needs, increase household welfare and alleviate poverty. Irrigated agriculture is an important strategy to enhance crop production, but it must be well tailored to specific socio-ecological settings, as otherwise, it might increase the burden of water-related parasitic diseases and delay economic advance. The purpose of this study is to assess and quantify the effect of ill health, particularly malaria, on the performance of farm activity, with an emphasis on drip-irrigated vegetable farming in rural Côte d'Ivoire. Vegetable yields and revenues were monitored among 12 farmers and linked with longitudinal medical and entomological surveys. Over the course of 10 months, farmers were classified as sick, on average, for 14-15 days, with malaria accounting for 8-9 days (58%), confirming that malaria is the most important disease in this setting. There was a large heterogeneity among farmers, with malaria-related work losses ranging between 0 and 26 days. Work absenteeism correlated with overall yields and revenues. During a single cabbage production cycle, those farmers who were prescribed sick because of malaria for more than 2 days (mean: 4.2 days) had 47% lower yields and 53% lower revenues than farmers who missed a maximum of 2 days (mean: 0.3 days). This is consequential in an intensive cropping system, where substitutes for qualified workers are not readily available. We conclude that mitigating the burden of malaria is an important step towards reducing the vulnerability of people engaged in intensive agricultural production. This calls for targeted interventions to facilitate agriculture-based rural development that might spur social and economic development and reduce inequities in sub-Saharan Africa.

Adult↗
PubMed2004

Community health outreach program of the Chad-Cameroon petroleum development and pipeline project.

A critical appraisal has been presented of the CHOP for a large-scale energy infrastructure development project that was implemented in two of the world's poorest countries. The project is under close scrutiny from various independent monitoring groups, civil society organizations, and human rights groups. Reviewing the achievements and shortcomings permits the extraction of important lessons that will be critical for the future adoption of the CHOP in the current setting and for the implementation of additional CHOPs elsewhere in the developing world. The authors believe that the design must be flexible, efficient, and innovative so that a CHOP promptly can address pressing public health issues as they arise (eg, epidemic outbreak) and include the needs and demands of the concerned communities. An innovative feature of the current project is the high degree and mix of public-private partnerships. The project's CHOP also relies on partnerships. As elaborated elsewhere, public-private partnerships should be seen as a social experiment--they reveal promise but are not the solution for every problem. For this CHOP, the focus is on partnerships between a multinational consortium, government agencies, and international organizations. The partnerships also include civil society organizations for monitoring and evaluation and local NGOs designated for the implementation of the selected public health interventions within the CHOP. The governments and their respective health policies often form the umbrella under which the partnerships operate. With the increase in globalization, however, the importance and capacities of governments have diminished, and there is growing private-sector involvement. Private enterprise is seen as an efficient, innovative, pragmatic, and powerful means to achieve environmental and social sustainability. Experiences with the partnership configurations in the current CHOP are of importance for tackling grand challenges in global health by applying a systemic approach. Other innovations of the project in general, and the CHOP in particular, are the strong emphases on institutional-capacity building, integration, and sustainability. In countries like Chad and Cameroon, there are serious shortages of well-qualified health personnel. The CHOP described in this article provides leverage for initiating better healthcare that will reduce the high burden of disease in the developing world. Reducing mortality rates for infants and children younger than 5 years in sub-Saharan Africa requires massive scaling-up of malaria-control interventions (eg, large-scale distribution of ITNs to protect millions of African children), thereby approaching the Abuja targets (see Armstrong Schellenberg et al). The local NGOs that took a lead within the framework of the CHOP in the distribution of ITNs and accompanying health education messages can extend these activities to communities living outside the vicinity of the project area. Serious shortcomings of the current CHOP, consistently identified by the external monitoring groups, include the lack of a regional health plan, cumulative impact assessment, and provision of clean water and sanitation outside the narrowly defined project area. This point is of central importance, particularly for Chad, where access to clean water and improved sanitation facilities is low. Another limitation of the current CHOP is the insufficient amount of significance addressed to tuberculosis and the apparent lack of concerted control efforts against HIV infection, AIDS, and tuberculosis. These criticisms, however, must be balanced against the lack of clarity in international discourse about the proper extent of responsibility of the corporate sector for dealing with the health problems of countries in which they do business. In an elegant analysis, the environmental risk factor "unsafe water, sanitation and hygiene" was shown to be one of the major contributors to loss of healthy life, particularly in the developing world. Provision of clean water and sanitation is a key factor for sustainable control of schistosomiasis and soil-transmitted helminths. Reduction of helminth infections might have a beneficial effect on the HIV and AIDS pandemic. The question still remains: What is, or should be, the scope and limits of responsibility of the corporate sector in solving these problems? There is a critical need for the monitoring and evaluation of the long-term impact of a CHOP that develops in parallel with a large development project, emphasizing the broadest possible determinants of health and well-being. To become operational, it requires the establishment and running of a longitudinal demographic surveillance system in the area and in adjacent areas that are unlikely to be affected by the project. This approach, coupled with regular household surveys for in-depth appraisal of health-seeking and asset indices, is the most promising source of data for impact measurement of health, poverty, and equity-related issues. It will facilitate subtle monitoring and surveillance activities, fostering a truly systemic approach by inclusion of all stake holders on the basis of the existing but constantly evolving system.

Cameroon↗
PubMed2004

Making a life worth living: neural correlates of well-being.

Despite the vast literature that has implicated asymmetric activation of the prefrontal cortex in approach-withdrawal motivation and emotion, no published reports have directly explored the neural correlates of well-being. Eighty-four right-handed adults (ages 57-60) completed self-report measures of eudaimonic well-being, hedonic well-being, and positive affect prior to resting electroencephalography. As hypothesized, greater left than right superior frontal activation was associated with higher levels of both forms of well-being. Hemisphere-specific analyses documented the importance of goal-directed approach tendencies beyond those captured by approach-related positive affect for eudaimonic but not for hedonic well-being. Appropriately engaging sources of appetitive motivation, characteristic of higher left than right baseline levels of prefrontal activation, may encourage the experience of well-being.

Attitude↗
PubMed2004

Increases in serum non-high-density lipoprotein cholesterol may be beneficial in some high-functioning older adults: MacArthur studies of successful aging.

UNLABELLED: objectives: To examine the association between changes in serum non-high-density lipoprotein cholesterol (non-HDL-C) over a 2.5-year period and risk of adverse health outcomes in the following 4.5 years in high-functioning older adults. DESIGN: Prospective cohort, established in 1988, with a follow-up in 1991 and 1995. SETTING: Population-based, community-dwelling men and women. PARTICIPANTS: A random sample (n=267) from the MacArthur cohort (N=1,189). The cohort represented the highest-functioning tertile of 4,030 screened candidates aged 70 to 79. MEASUREMENTS: Change in non-HDL-C between 1988 and 1991 was measured as a predictor of health outcomes between 1991 and 1995, including all-cause mortality, and among survivors, incident heart attack or stroke, development of new disability in basic activities of daily living, and decline in performance on the Short Portable Mental Status Questionnaire. RESULTS: More-positive change in non-HDL-C between 1988 and 1991 was associated with fewer adverse outcomes between 1991 and 1995. In individuals whose total cholesterol at baseline was in the middle two quartiles (195-244 mg/dL), each 10-mg/dL increase in the 1988-to-1991 change in non-HDL-C was associated with an adjusted mortality odds ratio (OR) of 0.67 (95% confidence interval (CI)=0.51-0.88). In individuals without cardiovascular disease at baseline, the adjusted OR for new physical disability was 0.79 (95% CI=0.65-0.95) and for cognitive decline was 0.81 (95% CI=0.67-0.98). CONCLUSION: Increases in cholesterol over time have beneficial associations in some older adults. The role of cholesterol changes in the health of older individuals needs further exploration.

Activities of Daily Living↗
PubMed2004

Integrated urban malaria control: a case study in dar es salaam, Tanzania.

The rapid growth of cities in sub-Saharan Africa, much of it driven by rural-urban migration, is associated with complex transformations of these ecosystems and an intricate set of challenges for malaria control. Urban malaria transmission is substantially less intense and much more focal than in rural and peri-urban settings. However, the danger of epidemics is higher and the presence of substantial non-immune populations places people of all ages at comparable levels of risk. The limited number of breeding sites in urban centers suggests that prevention strategies based on vector control, with emphasis on environmental management, should be a central feature of urban malaria control programs. We focus on malaria in the city of Dar es Salaam, Tanzania. Following a brief review of the 100-year history of malaria control in this urban center, we describe and evaluate a control program that operated from 1988 to 1996 as a consequence of a bilateral agreement between the governments of Tanzania and Japan. We present an innovative urban malaria risk mapping methodology based on high-resolution aerial photography with ground-based validation. This strategy clarifies that remote sensing technology at a level of resolution of one meter is essential if this kind of information is to play a role in guiding the detailed specification of intervention strategies for urban malaria control. The Tanzania-Japan multiple-intervention malaria control program, adaptively implemented over time, is described and evaluated with implications for urban malaria control in sub-Saharan Africa more generally.

Animals↗
PubMed2004

Urbanization in sub-saharan Africa and implication for malaria control.

Malaria not only remains a leading cause of morbidity and mortality, but it also impedes socioeconomic development, particularly in sub-Saharan Africa. Rapid and unprecedented urbanization, going hand-in-hand with often declining economies, might have profound implications for the epidemiology and control of malaria, as the relative disease burden increases among urban dwellers. Reviewing the literature and using a modeling approach, we find that entomologic inoculation rates in cities range from 0 to 54 per year, depending on the degree of urbanization, the spatial location within a city, and overall living conditions. Using the latest United Nations figures on urbanization prospects, nighttime light remotely sensed images, and the "Mapping Malaria Risk in Africa" results on climate suitability for stable malaria transmission, we estimate that 200 million people (24.6% of the total African population) currently live in urban settings where they are at risk of contracting the disease. Importantly, the estimated total surface area covered by these urban settings is only approximately 1.1-1.6% of the total African surface. Considering different plausible scenarios, we estimate an annual incidence of 24.8-103.2 million cases of clinical malaria attacks among urban dwellers in Africa. These figures translate to 6-28% of the estimated global annual disease incidence. Against this background, basic health care delivery systems providing early diagnosis and early treatment and preventive actions through mother and child health programs and the promotion of insecticide-treated bed nets for the rapidly growing numbers of the urban poor must be improved alongside well-tailored and integrated malaria control strategies. We propose environmental management and larviciding within well-specified productive sites as a main feature for such an integrated control approach. Mitigation of the current burden of malaria in urban African settings, in turn, is a necessity for stimulating environmentally and socially sustainable development.

Africa South of the Sahara↗
PubMed2003

Now you feel it, now you don't: frontal brain electrical asymmetry and individual differences in emotion regulation.

Recent theoretical accounts of emotion regulation assign an important role in this process to the prefrontal cortex, yet there is little relevant data available to support this hypothesis. The current study assessed the relation between individual differences in asymmetric prefrontal activation and an objective measure of uninstructed emotion regulation. Forty-seven participants 57 to 60 years old viewed emotionally arousing and neutral visual stimuli while eyeblink startle data were collected. Startle probes were also presented after picture presentation to capture the persistence or attenuation of affect following the offset of an emotional stimulus. Subjects with greater relative left-sided anterior activation in scalp-recorded brain electrical signals displayed attenuated startle magnitude after the offset of negative stimuli. This relation between resting frontal activation and recovery following an aversive event supports the idea of a frontally mediated mechanism involved in one form of automatic emotion regulation.

Affect↗
PubMed2003

Random spatial distribution of Schistosoma mansoni and hookworm infections among school children within a single village.

Schistosomes and soil-transmitted helminths currently infect a third of the world's human population. An important feature of these parasitic infections is their focal distribution, which has significant implications for control. Only a few studies have been carried out at the microepidemiological scale, comparing infection levels among individuals or households within a single village. In this study, data are presented from a cross-sectional survey, examining all children attending a primary school in rural Côte d'Ivoire over several consecutive days for Schistosoma mansoni, soil-transmitted helminths, and intestinal protozoa. All houses in the main village were mapped, and school children were linked to these households for small-area spatial analyses. Comparison between the 260 school children who live within the main village and the 89 children who reside in nearby settlements revealed significant differences in the overall prevalence and intensity of infections with S. mansoni and hookworm, confirming the focal nature of these 2 parasites. On the other hand, S. mansoni and hookworm infections exhibited random spatial patterns within the main village. The validity of these results is discussed in the context of this epidemiological setting, drawing attention to the issue of scale. Our findings have direct implications for intervention because they call for a uniform, community-wide approach to control schistosomiasis and soil-transmitted helminthiasis. Implementation can be relatively straightforward, and the proposed control approach might be cost-effective and prove sustainable.

Adolescent↗
PubMed2002

Association between Schistosoma mansoni and hookworm infections among schoolchildren in Côte d'Ivoire.

Infections with Schistosoma mansoni and hookworms are widespread in sub-Saharan Africa and the burden of disease associated with both parasites is enormous. Although there is a large overlap in their geographic distribution, little is known about the association between S. mansoni and hookworm infections and the underlying mechanisms. We explored this association among 325 schoolchildren from Côte d'Ivoire, by screening multiple stool specimens over consecutive days. We found a highly significant positive association between S. mansoni and hookworm infections with an adjusted odds ratio of 2.25 (95% confidence interval: 1.31-3.85; P=0.003). Increasing infection intensity of S. mansoni was significantly correlated with an increased likelihood of concomitant hookworm infections (chi(2)=20.72; P<0.001). Egg counts in stool specimens derived from a single day did not consistently reveal the positive association between the two parasites, which underlines the importance of repeated stool examinations. Several self-reported water contact patterns were significantly associated either with S. mansoni, hookworm or concomitant infections. Our findings are of considerable importance for tailoring effective health education messages that are readily adapted to the local epidemiological setting. Complemented with other control interventions, these measures might significantly reduce the burden caused by S. mansoni and hookworm infections.

Adolescent↗
PubMed2002

Allostatic load as a predictor of functional decline. MacArthur studies of successful aging.

Allostatic load has been proposed as a cumulative measure of dysregulation across multiple physiological systems, and has been postulated to impact health risks. In the allostatic load model, increased risk is hypothesized to result not only from large and clinically significant dysregulation in individual systems, but also from more modest dysregulation, if present in multiple systems. Our objective was to construct an allostatic load score by optimally combining several physiologic measurements, and to examine its association with future functional decline. We analyzed data from a 7-year longitudinal study of a community-based cohort, whose age at baseline was between 70 and 79 years. Canonical correlation analysis was used to study the association of 10 biological measurements representing allostatic load with declines in scores on five tests each of physical and cognitive function over two follow-up periods: 1998-1991 and 1991-1995. We used bootstrapping to evaluate the stability of the canonical correlation and canonical weights. The canonical correlation between allostatic load and the 20 decline scores was 0.43 (P =.03) and the [25th, 75th] percentile interval of its distribution over 200 bootstrapped subsamples of the cohort was [0.48, 0.53]. These findings were not substantially affected by adjusting for covariates and cardiovascular disease. We conclude that a summary measure of physiologic dysregulation, such as allostatic load, is an independent predictor of functional decline in elderly men and women.

Adaptation, Physiological↗
PubMed2002

The economic payoffs of integrated malaria control in the Zambian copperbelt between 1930 and 1950.

It has long been suggested that malaria is delaying the economic development of countries that are most severely affected by the disease. Several studies have documented the economic consequences of malaria at the household level, primarily in communities engaged in subsistence farming. A missing element is the appraisal of the economic impact of malaria on the industrial and service sectors that will probably become the backbone of many developing economies. We estimate the economic effects of integrated malaria control implemented during the colonial period and sustained for 20 years in four copper mining communities of the former Northern Rhodesia (now Zambia). Integrated malaria control was characterized by strong emphasis on environmental management, while part of the mining communities also benefited from rapid diagnosis and treatment and the use of bednets. The programmes were highly successful as an estimated 14,122 deaths, 517,284 malaria attacks and 942,347 work shift losses were averted. Overall, 127,226 disability adjusted life years (DALYs) were averted per 3-year incremental period. The cumulative costs of malaria control interventions were 11,169,472 US dollars (in 1995 US dollars). Because the control programmes were so effective, the mining companies attracted a large reservoir of migrant labourers and sustained healthy work forces. The programmes averted an estimated 796,622 US dollars in direct treatment costs and 5,678,745 US dollars in indirect costs as a result of reduced work absenteeism. Within a few years of programme initiation, Northern Rhodesia became the leading copper producer in Africa, and mining generated the dominant share of national income. Copper production and revenues, which increased dramatically during malaria control interventions, amounted to the equivalent of 7.1 billion US dollars (in 1995 US dollars). Integrated malaria control in copper mining communities was a sound investment. It had payoff for public and occupational health, generally, and without it copper extraction and social and economic development would have been impossible.

Absenteeism↗
PubMed2002

A gender gap in the next generation of physician-scientists: medical student interest and participation in research.

BACKGROUND: For 2 decades, the number of physician-scientists has not kept pace with the overall growth of the medical research community. Concomitantly, the number of women entering medical schools has increased markedly. We have explored the effect of the changing gender composition of medical schools on the present and future pipeline of young physician-scientists. METHODS: We analyzed data obtained from the Association of American Medical Colleges, the National Institutes of Health, and the Howard Hughes Medical Institute pertaining to the expressed research intentions or research participation of male and female medical students in the United States. RESULTS: A statistically significant decline in the percentage of matriculating and graduating medical students--both men and women-who expressed strong research career intentions occurred during the decade between 1987 and 1997. Moreover, matriculating and graduating women were significantly less likely than men to indicate strong research career intentions. Each of these trends has been observed for medical schools overall and for research-intensive ones. Cohort data obtained by tracking individuals from matriculation to graduation revealed that women who expressed strong research career intentions upon matriculation were more likely than men to decrease their research career intentions during medical school. Medical student participation in research supported the gender gap identified by assessing research intentions. Female medical student participation in the Medical Scientist Training Program and the Howard Hughes Medical Institute/National Institutes of Health-sponsored Cloisters Program has increased but lags far behind the growth in the female population in medical schools. CONCLUSION: Three worrisome trends in the research career intentions and participation of the nation's medical students (a decade-long decline for both men and women, a large and persistent gender gap, and a negative effect of the medical school experience for women) presage a further decline in the physician-scientist pipeline unless they are reversed promptly and decisively.

Biomedical Research↗
PubMed2002

Polyparasitism with Schistosoma mansoni, geohelminths, and intestinal protozoa in rural Côte d'Ivoire.

Single species infections with schistosomes, geohelminths, and intestinal protozoans are common over large parts of sub-Saharan Africa, and it is expected that polyparasitism affects a considerable proportion of the population, hence posing a great toll on public health. However, few investigations have been carried out to quantify the extent of polyparasitism. Here, a detailed assessment is reported for the epidemiology of Schistosoma mansoni, geohelminths, and intestinal protozoan infections, with particular emphasis on polyparasitism among 260 community members in rural Cĵte d'Ivoire. Schistosoma mansoni, Entamoeba coli, and hookworm were the predominant species with prevalences of 71.5, 64.6, and 51.9%, respectively. Only 8 individuals displayed no infection, whereas two-thirds of the population harbored 3 or more parasites concurrently. There were a series of significant pairwise parasite co-occurrences, e.g., between S. mansoni and hookworms and between S. mansoni and E. coli. It is concluded that polyparasitism in the population studied here was very common, which is probably the case also in other areas of rural Cĵte d'Ivoire and elsewhere in sub-Saharan Africa. These findings call for integrated approaches to effectively control multiple parasitic and protozoan infections.

Adolescent↗