[Change of protocol in the verbal autopsy method and measure of malaria mortality in rural areas in Senegal]. / Changement de protocole dans la méthode d'autopsie verbale et mesure de la mortalité palustre en milieu rural sénégalais.

In rural Senegal, three populations have been followed up since several decades and the malaria mortality trend has been observed since the mid-1980s. However, limits are associated with the verbal autopsy method used to determine causes of death, especially deaths due to malaria. A change in protocol occurred in recent years in two of these three sites with the involvement of two physicians (instead of only one) in the diagnosis. The objective is here to measure its potential impact on diagnosis of malaria deaths. Five hundred and fifteen diagnoses reported on child deaths occurred from 2000 to 2005 have been analysed. We have identified, on the basis of a multinomial logistic regression model, factors affecting the determination of malaria deaths among the characteristics of the child, the death, the illness and its symptoms, and we also took into account method factors. Factors related to the method do not play on the malaria diagnosis. This result insures the continuity of the series on malaria mortality statistics since 2000 in the two sites despite changes in the method. However, the new protocol leads to vanish possibility of having deaths among ill-defined or unknown causes. In the African context of absence of health statistics, data obtained through the verbal autopsy method in demographic surveillance system can provide accurate information in the epidemiological field, even regarding malaria.

[The incidence of snakebite in a rural zone of southeastern Senegal]. / L'incidence des morsures de serpent en zone rurale au Sénégal oriental.

In order to complete an exploratory study on the risk of death due to snakebite in a rural zone of South-Eastern Senegal, we have carried out a survey to estimate the incidence of snakebites in the same population. The study made on a sample of almost 600 subjects showed an annual incidence of 677 bites per 100.000 inhabitants, that is one of the most important rate ever reported in the world until now. Based on these results and data collected previously on deaths due to snakebites in this same population, we provide an estimate of snakebite case fatality rate of 2.1% in this area of Senegal.

[Methodology for household surveys: the case of two investigations carried out (example of Bandafassi, Senegal)]. / Mesurer l'incidence des morsures de serpent: méthodologie d'enquête auprès des ménages (l'exemple de Bandafassi, Sénégal).

The survey area of Bandafassi, in Eastern Senegal, was the subject of two studies each allowing to measure the risk of bite and death consecutive to a snakebite in a rural area. Two different methods were being used to carry out these investigations. Although both were based on the visit of households, the sample of the first study was designed to be representative of the population (the zone of study of Bandafassi is the subject of a regular demographic follow-up since 1970) while the second study was carried out by interviewing the concession (groups of households) heads. Therefore, the analysis of these surveys must take into account the sampling discrepancies. In spite of the different methodologies, similarities in the results obtained validate both methods and permitted to explain the small variations observed and to measure bias relative to this type of investigations.

[Mortality from snake bites, wild and domestic animal bites and arthropod stings in the savannah zone of eastern Senegal]. / La mortalité par les morsures de serpent, d'animaux sauvages et domestiques et les piqûres d'arthropodes en zone de savane soudanienne du Sénégal oriental.

From 1976 to 1999, we conducted a prospective study of overall and cause-specific mortality among the population of 42 villages of south-eastern Senegal. Of 4,228 deaths registered during this period, 26 were brought on by snakebites, 4 by invertebrate stings and 8 by other wild or domestic animals. The average annual mortality rate from snakebite was 14 deaths per 100,000 population. Among persons aged 1 year or more, 0.9% (26/2,880) of deaths were caused by snakebite and this cause represented 28% (26/94) of the total number of deaths by accident. We also investigated the snake fauna of the area. Of 1,280 snakes belonging to 34 species that were collected, one-third were dangerous and the proportion of Viperidae, Elapidae and Atractaspididae was 23%, 11% and 0.6%, respectively. The saw-scaled viper Echis ocellatus was the most abundant species (13.6%). Other venomous species were Causus maculatus (6.5%), Naja katiensis (5.5%), Bitis arietans (2.7%), Elapsoidea trapei (2.4%), Naja nigricollis (1.2%), Naja melanoleuca (1.1%), Atractaspis aterrima (0.4%), Dendroaspis polylepis (0.3%) and Naja haje (0.1%).

High mortality from snakebite in south-eastern Senegal.

Over 24 years, from 1976 to 1999, we conducted a prospective study of overall and cause-specific mortality among the population of 42 villages of south-eastern Senegal. Of 4228 deaths registered during this period, 26 were caused by snakebite, 4 by invertebrate stings and 8 by other wild or domestic animals. The average annual mortality rate from snakebite was 14 deaths per 100,000 population. Among persons aged > or = 1 year, 0.9% (26/2880) of deaths were caused by snakebite and this cause represented 28% (26/94) of total deaths by accidents. We also investigated the snake fauna of the area. Of 1280 snakes belonging to 34 species that were collected, one-third were dangerous and the proportion of Viperidae, Elapidae and Atractaspidae was 23%, 11% and 0.6%, respectively. The saw-scaled viper Echis ocellatus was the most abundant species (13.6%). Other venomous species were Causus maculatus (6.5%), Naja katiensis (5.5%), Bitis arietans (2.7%), Elapsoidea trapei (2.4%), Naja nigricollis (1.2%), Naja melanoleuca (1.1%), Atractaspis aterrima (0.4%), Dendroaspis polylepis (0.3%) and Naja haje (0.1%).