With the paradigm shift from the reduction of morbidity and mortality to the interruption of transmission, the focus of malaria control broadens from symptomatic infections in children ?5 years of age to include asymptomatic infections in older children and adults. In addition, as control efforts intensify and the number of interventions increases, there will be decreases in prevalence, incidence and transmission with additional decreases in morbidity and mortality. Expected secondary consequences of these changes include upward shifts in the peak ages for infection (parasitemia) and disease, increases in the ages for acquisition of antiparasite humoral and cellular immune responses and increases in false-negative blood smears and rapid diagnostic tests. Strategies to monitor these changes must include: (1) studies of the entire population (that are not restricted to children ?5 or ?10 years of age), (2) study sites in both cities and rural areas (because of increasing urbanization across sub-Saharan Africa) and (3) innovative strategies for surveillance as the prevalence of infection decreases and the frequency of false-negative smears and rapid diagnostic tests increases.
The study sites for the West African ICEMR are in three countries (The Gambia, Senegal, Mali) and are located within 750 km of each other. In addition, the National Malaria Control Programmes of these countries have virtually identical policies: (1) Artemisinin Combination Therapies (ACTs) for the treatment of symptomatic Plasmodium falciparum infection, (2) Long-Lasting Insecticide-treated bed Nets (LLINs) to reduce the Entomololgic Inoculation Rate (EIR), and (3) sulfadoxine-pyrimethamine for the Intermittent Preventive Treatment of malaria during pregnancy (IPTp). However, the prevalence of P. falciparum malaria and the status of malaria control vary markedly across the four sites with differences in the duration of the transmission season (from 4-5 to 10-11 months), the intensity of transmission (with EIRs from unmeasurably low to 4-5 per person per month), multiplicity of infection (from a mean of 1.0 to means of 2-5) and the status of malaria control (from areas which have virtually no control to areas that are at the threshold of malaria elimination). The most important priority is the need to obtain comparable data on the population-based prevalence, incidence and transmission of malaria before new candidate interventions or combinations of interventions are introduced for malaria control.
Approximately one million newborn babies die every year as a result of birth asphyxia in developing countries. The objectives of this study are to develop the management of birth asphyxia and to establish a community-based surveillance system of vital events in rural areas of Oueléssébougou, Mali. Traditional birth attendants, female leaders of village associations and village health workers were trained to carry out communication activities designed to change behaviours in the management of birth asphyxia. The study has improved health facility-based delivery (from 80 to 93%) and the identification of birth asphyxia (11 to 12% new born babies have been resuscitated). As a result of training and supervising community actors, the quality of delivery is improved and neonatal mortality is reduced.
In African cities where environmental, social and economic problems facilitate the development of urban pathology, inadequate or ineffective health facilities raise the question of access to quality care, especially for slum dwellers. The city of Nouakchott marked by a multifaceted urban crisis is an illustration of this troubling situation. To analyse the spatial organisation and functioning of the healthcare system by assessing the use of health services, we studied this utilisation in August 2004 in three areas of the city by a cross-sectional survey of 836 households. The results show that therapeutic itineraries are as diverse as health care provision is varied. About 50.8 % of those seeking health care reported using modern services (public health clinics, private clinics, private doctors or nurses) for the most common diseases (acute respiratory infection and diarrhea) in their community, but this rate varied significantly by disease, social category and neighborhood. Thus, this mediocre level of utilisation of public health clinics is due to the poor quality of care provided. Moreover, healthcare services are often used only in case of severe or worsening illness, with signs (e.g., cough and persistent fever, or weight loss) seen to suggest more serious diseases, such as tuberculosis, meningitis or severe malaria. Geographic accessibility of health services was relatively good (70 %). It was the economic, socio-cultural, organizational and functional factors that appeared to determine the choice to use modern health care. The slackening of socio-cultural and organizational constraints and adaptation to economic ones should help to improve health policies and foster a functioning healthcare system.
We present results of two intensive mark-release-recapture surveys conducted during the wet and dry seasons of 2008 in the villages of Fourda and Kenieroba, Mali. The former is a small fishing village by the Niger River with a moderate to high densities of Anopheles gambiae Giles s.s. (Diptera: Culicidae) throughout the year, while the latter is a large agricultural community 2 km inland that experiences strong seasonal fluctuation in An. gambiae densities. We estimate the population size of female An. gambiae in Fourda to be in less than 3,000 during the dry season. We found evidence of large population size and migration from Fourda in Kenieroba during the wet season, but very low numbers and no sign of migrants during the dry season. We suggest that malaria vector control measures aimed at adult mosquitoes might be made more efficient in this region and other seasonal riparian habitats by targeting disruption of mosquito populations by the river during the dry season. This would decrease the size of an already small population, and would be likely to delay the explosive growth in vector numbers in the larger inland villages as rainfall increases.
Despite the protection provided by several factors, including maternal antibodies, the burden of malaria in young infants may be higher than previously thought. Infants with congenital or neonatal malaria may have a different clinical presentation than older children, and diagnosis may be confused with other neonatal diseases due to an overlap of clinical manifestations. In addition, there is little information on the use of artemisinin-based combination therapy in young infants. There is the need for a more accurate estimate of the parasite prevalence and the incidence of clinical malaria in infants under 6 months old, as well as a better characterization of risk factors, pharmacokinetic profiles, safety and efficacy of currently available anti-malarial treatments, in order to develop evidence-based treatment guidelines for this population.
This survey was carried out in the coastal lowlands of Guinea-Conakry in order to make an inventory of plants used by traditional healers, herbalists and diabetic patients for the management of diabetes mellitus.
The epidemiology of malaria in the Senegal River Gorgol valley, southern Mauritania, requires particular attention in the face of ongoing and predicted environmental and climate changes. While "malaria cases" are reported in health facilities throughout the year, past and current climatic and ecological conditions do not favour transmission in the dry season (lack of rainfall and very high temperatures). Moreover, entomological investigations in neighbouring regions point to an absence of malaria transmission in mosquito vectors in the dry season. Because the clinical signs of malaria are non-specific and overlap with those of other diseases (e.g. acute respiratory infections and diarrhoea), new research is needed to better understand malaria transmission patterns in this region to improve adaptive, preventive and curative measures.
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