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Marcel Tanner

Publications and source records attributed to Marcel Tanner.

At least 37 records · Page 2Linked to original sources

Tribendimidine: a promising, safe and broad-spectrum anthelmintic agent from China.

We review, for the first time, a 20-year Chinese story of research and development pertaining to tribendimidine, a promising anthelmintic agent that is safe and exhibits a broad spectrum of activity. Tribendimidine was first synthesized at the National Institute of Parasitic Diseases in Shanghai in the mid 1980s. In laboratory studies, tribendimidine showed high efficacy against Nippostrongylus braziliensis in rats, Necator americanus in hamsters, Ancylostoma caninum and Toxocara canis in dogs, and Syphacia mesocriceti in mice. Activity was also found against several species of cestodes in chicken. In clinical trials, a single oral dose of 400 mg tribendimidine, administered to patients infected only with N. americanus, or with N. americanus and Ancylostoma duodenalis, resulted in cure rates of 85.7% (132/154) and 89.8% (53/59), respectively. In comparison, a single oral dose of 400 mg albendazole resulted in significantly lower cure rates, namely 65.5% (91/139; chi(2) = 16.47, P < 0.001) and 71.7% (43/60; chi(2) = 6.29, P = 0.012), respectively. Single oral doses of tribendimidine (300 mg) and albendazole (400mg) were equally effective against Ascaris lumbricoides infections; cure rates were 96.0% (97/101) and 98.1% (101/103), respectively. In 5-14-year-old children with an Enterobius vermicularis infection, treated with a single oral dose of 200 mg tribendimidine, a cure rate of 81.6% (93/114) was observed. Tribendimidine was well-tolerated as only mild and transient side effects were observed. It would be of great public health significance if these findings are confirmed in other epidemiological settings, as more than one-quarter of the world population is currently affected by intestinal nematodes, with only very few drugs currently available on the market.

Animals↗

Effect of irrigated rice agriculture on Japanese encephalitis, including challenges and opportunities for integrated vector management.

Japanese encephalitis (JE) is a disease caused by an arbovirus that is spread by marsh birds, amplified by pigs, and mainly transmitted by the bite of infected Culex tritaeniorhynchus mosquitoes. The estimated annual incidence and mortality rates are 30,000--50,000 and 10,000, respectively, and the estimated global burden of JE in 2002 was 709,000 disability-adjusted life years lost. Here, we discuss the contextual determinants of JE, and systematically examine studies assessing the relationship between irrigated rice agriculture and clinical parameters of JE. Estimates of the sizes of the rural population and population in irrigated areas are presented, and trends of the rural population, the rice-irrigated area, and the rice production are analyzed from 1963 to 2003. We find that approximately 1.9 billion people currently live in rural JE-prone areas of the world. Among them 220 million people live in proximity to rice-irrigation schemes. In 2003, the total rice harvested area of all JE-endemic countries (excluding the Russian Federation and Australia) was 1,345,000 km(2). This is an increase of 22% over the past 40 years. Meanwhile, the total rice production in these countries has risen from 226 millions of tonnes to 529 millions of tonnes (+134%). Finally, we evaluate the effect of different vector control interventions in rice fields, including environmental measures (i.e. alternate wet and dry irrigation (AWDI)), and biological control approaches (i.e. bacteria, nematodes, invertebrate predators, larvivorous fish, fungi and other natural products). We conclude that in JE-endemic rural settings, where vaccination rates are often low, an integrated vector management approach with AWDI and the use of larvivorous fish as its main components can reduce vector populations, and hence has the potential to reduce the transmission level and the burden of JE.

Agriculture↗

Female genital mutilation in the context of migration: experience of African women with the Swiss health care system.

BACKGROUND: In contrast to other European countries, the Swiss health care system does not deal with the specific needs of women with female genital mutilation (FGM) in a consistent manner, though migrants from countries where FGM is commonly practised are living in Switzerland. METHODS: For this study, the interaction of women who had undergone FGM, with the Swiss health services was analysed both from the perspective of the women concerned and that of health care professionals (doctors and midwives). The methods used were mainly qualitative, including focus group discussions with 29 women from Somalia and Eritrea and telephone interviews with 37 health care professionals. RESULTS: It is estimated that some 6000 girls and women with FGM could be living in Switzerland. The fact that health care providers rarely see such patients and the absence of professional guidelines give rise to misunderstandings. Counselling of the women is often inadequate, and there is a striking lack of communication about FGM between health care providers and users, as well as within the women's communities. As a surprising finding, reinfibulation is carried out in Switzerland when requested by the patient. CONCLUSIONS: This study shows that at present the specific gynaecological and obstetric health care needs of migrant women who have undergone FGM are not adequately addressed in the Swiss health system. The situation could be easily improved by taking into consideration the fairly simple measures suggested by the women and the health care providers taking part in this study. KEY POINTS: Due to international migration, female genital mutilation (FGM) has become an issue of increasing concern in host countries such as Switzerland. Objectives of this study were to analyze how immigrant women with FGM experience gynaecological/obstetrical care in the Swiss health care system, and to investigate if gynaecologists/obstetricians and midwives treat and counsel FGM related complications adequately. Specific health care needs of women with FGM should--and easily could--be better considered by the Swiss health care system. Recommended measures include capacity building and professional guidelines on FGM for health care providers; and access to culturally appropriate information and self-help groups for the communities concerned.

Adolescent↗

Disparities in parasitic infections, perceived ill health and access to health care among poorer and less poor schoolchildren of rural Côte d'Ivoire.

Differences in the state of health between rural and urban populations living in Africa have been described, yet only few studies analysed inequities within poor rural communities. We investigated disparities in parasitic infections, perceived ill health and access to formal health services among more than 4000 schoolchildren from 57 primary schools in a rural area of western Côte d'Ivoire, as measured by their socioeconomic status. In a first step, we carried out a cross-sectional parasitological survey. Stool specimens and finger prick blood samples were collected and processed with standardized, quality-controlled methods, for diagnosis of Schistosoma mansoni, soil-transmitted helminths, intestinal protozoa and Plasmodium. Then, a questionnaire survey was carried out for the appraisal of self-reported morbidity indicators, as well as housing characteristics and household assets ownership. Mean travel distance from each village to the nearest health care delivery structure was provided by the regional health authorities. Poorer schoolchildren showed a significantly higher infection prevalence of hookworm than better-off children. However, higher infection prevalences of intestinal protozoa (i.e. Blastocystis hominis, Endolimax nana and Iodamoeba butschlii) were found with increasing socioeconomic status. Significant negative associations were observed between socioeconomic status and light infection intensities with hookworm and S. mansoni, as well as with several self-reported morbidity indicators. The poorest school-attending children lived significantly further away from formal health services than their richer counterparts. Our study provides evidence for inequities among schoolchildren's parasitic infection status, perceived ill health and access to health care in a large rural part of Côte d'Ivoire. These findings call for more equity-balanced parasitic disease control interventions, which in turn might be an important strategy for poverty alleviation.

Adolescent↗

Effect of irrigation and large dams on the burden of malaria on a global and regional scale.

Human-made ecologic transformations have occurred at an unprecedented rate over the past 50 years. Prominent among them are water resource development projects. An estimated 40,000 large dams and 800,000 small dams have been built, and 272 million hectares of land are currently under irrigation worldwide. The establishment and operation of water projects has had a history of facilitating a change in the frequency and transmission dynamics of malaria, but analyses of these environmental risk factors are sparse. Here, we present a comprehensive review of studies that assessed the impact of irrigation and dam building on malaria prevalence or incidence, stratified by the World Health Organization's (WHO) sub-regions of the world, and link these studies with the latest statistics on disability adjusted life years, irrigated agriculture, and large dams. We also present estimates of the population at risk due to proximity to irrigation schemes and large dam reservoirs. In WHO sub-regions 1 and 2, which have 87.9% of the current global malaria burden, only 9.4 million people are estimated to live near large dams and irrigation schemes. In contrast, the remaining sub-regions concentrate an estimated 15.3 million people near large dams and up to 845 million near irrigation sites, while here only 12.1% of the global malaria burden is concentrated. Whether an individual water project triggers an increase in malaria transmission depends on the contextual determinants of malaria, including the epidemiologic setting, socioeconomic factors, vector management, and health seeking behavior. We conclude that in unstable malaria endemic areas, integrated malaria control measures, coupled with sound water management, are mandatory to mitigate the current burden of malaria in locations near irrigation or dam sites.

Endemic Diseases↗

Effect of water resource development and management on lymphatic filariasis, and estimates of populations at risk.

Lymphatic filariasis (LF) is a debilitating disease overwhelmingly caused by Wuchereria bancrofti, which is transmitted by various mosquito species. Here, we present a systematic literature review with the following objectives: (i) to establish global and regional estimates of populations at risk of LF with particular consideration of water resource development projects, and (ii) to assess the effects of water resource development and management on the frequency and transmission dynamics of the disease. We estimate that globally, 2 billion people are at risk of LF. Among them, there are 394.5 million urban dwellers without access to improved sanitation and 213 million rural dwellers living in close proximity to irrigation. Environmental changes due to water resource development and management consistently led to a shift in vector species composition and generally to a strong proliferation of vector populations. For example, in World Health Organization (WHO) subregions 1 and 2, mosquito densities of the Anopheles gambiae complex and Anopheles funestus were up to 25-fold higher in irrigated areas when compared with irrigation-free sites. Although the infection prevalence of LF often increased after the implementation of a water project, there was no clear association with clinical symptoms. Concluding, there is a need to assess and quantify changes of LF transmission parameters and clinical manifestations over the entire course of water resource developments. Where resources allow, integrated vector management should complement mass drug administration, and broad-based monitoring and surveillance of the disease should become an integral part of large-scale waste management and sanitation programs, whose basic rationale lies in a systemic approach to city, district, and regional level health services and disease prevention.

Elephantiasis, Filarial↗

A Bayesian-based approach for spatio-temporal modeling of county level prevalence of Schistosoma japonicum infection in Jiangsu province, China.

Spatio-temporal variations of Schistosoma japonicum infection risk in Jiangsu province, China, were examined and the relationships between key climatic factors and infection prevalence at the county level were determined. The parasitological data were collected annually by means of cross-sectional surveys carried out in 47 counties from 1990 to 1998. Climatic factors, namely land surface temperature (LST) and normalized difference vegetation index (NDVI), were obtained from remote sensing satellite sensors. Bayesian spatio-temporal models were employed to analyze the data. The best fitting model showed that spatial autocorrelation in Jiangsu province decreased dramatically from 1990 to 1992 and increased gradually thereafter. A likely explanation of this finding arises from the large-scale administration of praziquantel for morbidity control of schistosomiasis. Our analysis suggested a negative association between NDVI and risk of S. japonicum infection. On the other hand, an increase in LST contributed to a significant increase in S. japonicum infection prevalence. We conclude that combining geographic information system, remote sensing and Bayesian-based statistical approaches facilitate integrated risk modeling of S. japonicum, which in turn is of relevance for allocation of scarce resources for control of schistosomiasis japonica in Jiangsu province and elsewhere in China, where the disease remains of public health and economic significance.

Bayes Theorem↗

Metabonomic investigations in mice infected with Schistosoma mansoni: an approach for biomarker identification.

Schistosomiasis, a chronic and debilitating parasitic disease, affects approximately 200 million people in the developing world and imposes a substantial public health and economic impact. Accurately diagnosing at the individual level, monitoring disease progression, and assessing the impact of pharmacological interventions at the population level are of prime importance for controlling schistosomiasis. Using a Schistosoma mansoni-mouse model, we present a characterization of a parasitic infection by metabolic profiling, employing (1)H NMR spectroscopy and multivariate pattern recognition techniques. We infected 10 mice with 80 S. mansoni cercariae each and collected urine samples 49 and 56 days postinfection. Urine samples were also obtained from 10 uninfected control mice at the same time. The metabolic signature of an S. mansoni infection consists of reduced levels of the tricarboxylic acid cycle intermediates, including citrate, succinate, and 2-oxoglutarate, and increased levels of pyruvate, suggesting stimulated glycolysis. A disturbance of amino acid metabolism was also associated with an S. mansoni infection, as indicated by depletion of taurine, 2-oxoisocaproate, and 2-oxoisovalerate and elevation of tryptophan in the urine. A range of microbial-related metabolites, i.e., trimethylamine, phenylacetylglycine, acetate, p-cresol glucuronide, butyrate, propionate, and hippurate, were also coupled with an S. mansoni infection, indicating disturbances in the gut microbiota. Our work highlights the potential of metabolic profiling to enhance our understanding of biological responses to parasitic infections. It also holds promise as a basis for novel diagnostic tests with high sensitivity and specificity and for improved disease surveillance and control.

Animals↗

Multiple parasite infections and their relationship to self-reported morbidity in a community of rural Côte d'Ivoire.

BACKGROUND: Concomitant parasitic infections are common in the developing world, yet most studies focus on a single parasite in a narrow age group. We investigated the extent of polyparasitism and parasite associations, and related these findings to self-reported morbidity. METHODS: Inhabitants of 75 randomly selected households from a single village in western Côte d'Ivoire provided multiple faecal specimens and a single finger prick blood sample. The Kato-Katz technique and a formol-ether concentration method were employed to screen faecal samples for Schistosoma mansoni, soil-transmitted helminths and intestinal protozoa. Giemsa-stained blood smears were analysed for malaria parasites. A questionnaire was administered for collection of demographic information and self-reported morbidity indicators. RESULTS: Complete parasitological data were obtained for 500/561 (89.1%) participants, similarly distributed among sex, with an age range from 5 days to 91 years. The prevalences of Plasmodium falciparum, hookworms, Entamoeba histolytica/E. dispar, and S. mansoni were 76.4%, 45.0%, 42.2%, and 39.8%, respectively. Three-quarters of the population harboured three or more parasites concurrently. Multivariate analysis revealed significant associations between several pairs of parasites. Some parasitic infections and the total number of parasites were significantly associated with self-reported morbidity indicators. CONCLUSIONS: Our data confirm that polyparasitism is very common in rural Côte d'Ivoire and that people have clear perceptions about the morbidity caused by some of these parasitic infections. Our findings can be used for the design and implementation of sound intervention strategies to mitigate morbidity and co-morbidity.

Adolescent↗

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↗

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↗

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↗

Efficacy and side effects of praziquantel against Schistosoma mansoni in a community of western Côte d'Ivoire.

Praziquantel is efficacious against the adult stages of all human schistosome parasites, and has become the drug of choice for morbidity control of schistosomiasis. There is concern that resistance to praziquantel might develop or already exists, and could be further facilitated through new control initiatives relying on large-scale administration of praziquantel. Therefore, monitoring praziquantel efficacy in different epidemiological settings is required. We assessed the efficacy and side effects of praziquantel against Schistosoma mansoni in a rural community of western Côte d'Ivoire. Three consecutive stool specimens from 545 children and adults were examined by the Kato-Katz technique, revealing an overall prevalence of 40.9%. S. mansoni-infected individuals were treated with a single oral dose of praziquantel at 40 mg/kg. The most frequent side effects were abdominal pain, dizziness and diarrhoea. The overall cure rate, assessed 6 weeks post-treatment, was 60.9%. Moderate or heavy infections were only cleared in half or one-third of the individuals, respectively. The total egg count reduction was 61.4%. Infection intensity pre-treatment was significantly associated with age, cure rate, reported diarrhoea and dizziness. Our findings call for additional studies that rigorously evaluate the efficacy of praziquantel against different schistosome species in entire communities, using similarly sensitive diagnostic approaches as employed here.

Administration, Oral↗

The changing epidemiology of malaria in Ifakara Town, southern Tanzania.

Between 1995 and 2000 there were marked changes in the epidemiology of malaria in Ifakara, southern Tanzania. We documented these changes using parasitological and clinical data from a series of community- and hospital-based studies involving children up to the age of 5 years. There was a right shift and lowering in the age-specific parasite prevalence in the community-based cohort studies. The incidence of clinical malaria in placebo-receiving infants in additional study cohorts dropped from 0.8 in 1995 to 0.43 episodes per infant per year in 2000, an incidence rate ratio of 0.53 (95% confidence interval: 0.404, 0.70, P<0.0001). At the same time, there was an increase in the total number of malaria admissions and a marked right shift in the age pattern of these admissions (median age in 1995 1.55 years vs. 2.33 in 2000, P<0.0001). However, the burden of malaria deaths remained in infants. We discuss how these dramatic changes in the epidemiology of malaria may have arisen from the use of currently available malaria control tools. Caution is required in the interpretation of hospital-based data as it is likely to underestimate the impact of anaemia on mortality in the community, where most paediatric deaths occur. Even in low/moderate malaria transmission settings, where older children suffer most malaria episodes, targeting effective malaria control at infants may produce important reductions in infant mortality caused by malaria.

Age Distribution↗

Diarrhoea, vomiting and the role of milk consumption: perceived and identified risk in Bamako (Mali).

OBJECTIVES: To evaluate the public health impact of milk contamination in Bamako, Mali. METHODS: A case-control study assessed the risk-factors for food-borne toxi-infections with diarrhoea and vomiting as main clinical picture. A total of 131 schoolchildren between 5 and 20 years of age were interviewed by trained interviewers in schools in Bamako. A structured questionnaire was used to record health problems, food and particularly milk consumption habits and socio-economic indicators. RESULTS: Final multivariate logistic regression analysis identified regular consumption of boiled milk [odds ratio(OR) = 4.38; 95% CI = 1.15-16.71], age between 5 and 10 years (OR vs. age group 11-15 years = 3.28; 95% CI = 1.09-9.85) and the existence of dry latrines in the household (OR = 7.65; 95% CI = 1.92-30.55) as risk factors for diarrhoea and vomiting. Other milk products and the socio-economic level of the household were not significantly associated with the outcome. Many people were unaware of the potential risks of milk consumption. CONCLUSIONS: Milk products may be a risk factor for food-borne toxi-infections. Attention has to be paid to products considered 'safe', such as boiled or pasteurized milk. The low awareness of potential risks of many people may increase the risk of milk consumption. To achieve a sustainable increase in local milk production in Africa, milk quantity and production and transformation quality should be improved simultaneously.

Adolescent↗

Mosquito nets and the poor: can social marketing redress inequities in access?

Treated mosquito nets are a practical malaria control tool. However, implementation of efficient delivery mechanisms remains a challenge. We investigated whether social marketing of treated mosquito nets results in decreased equity in rural Tanzania, through household surveys before the start of a social marketing programme and 3 years later. About 12,000 household heads were asked about ownership of nets and other assets including a tin roof, radio, or bicycle. A socio-economic status score was developed for each household. Net ownership was calculated for households in each quintile of this score, from poorest to least poor. In 1997, about 20% of the poorest households and over 60% of the least poor households owned a mosquito net. Three years later, more than half of the poorest households owned a net, as did over 90% of the least poor: the ratio of net ownership among the poorest to least poor increased from 0.3 in 1997 to 0.6 in 2000. Social marketing in the presence of an active private sector for nets was associated with increased equity.

Animals↗

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↗