New malaria-control policies and child mortality in senegal: reaching millennium development goal 4.

BACKGROUND: The Demographic Surveillance System established in 1962 in Niakhar, Senegal, is the oldest in Africa. Here, we analyze trends in overall child mortality, malaria, and other causes of death in Niakhar from the beginning of data collection to 2010. METHODS: After an initial census, demographic data were updated yearly from 1963 through 2010. From 1984, causes of death were determined by the verbal autopsy technique. RESULTS: During 1963-2010, infant and under-5 mortality rates decreased from 223‰ to 18‰ and from 485‰ to 41‰, respectively. The decrease was progressive during the entire observation period, except during 1990-2000, when a plateau and then an increase was observed. Malaria-attributable mortality in under-5 children decreased from 13.5‰ deaths per 1000 children per year during 1992-1999 to 2.2‰ deaths per 1000 children per year in 2010. During this period, all-cause mortality among children aged <5 years decreased by 80%. CONCLUSIONS: Inadequate treatment for chloroquine-resistant malaria and an epidemic of meningitis during the 1990s were the 2 factors that interrupted a continuous decrease in child mortality. Direct and indirect effects of new malaria-control policies, introduced in 2003 and completed during 2006-2008, are likely to have been the key cause of the recent dramatic decrease in child mortality.

Reduction in risk-taking behaviors among MSM in Senegal between 2004 and 2007 and prevalence of HIV and other STIs. ELIHoS Project, ANRS 12139.

An epidemiological survey conducted in Senegal in 2004 among men having sex with men (MSM) revealed high HIV prevalence and a high rate of risky behaviors within this population. Consequently, several prevention campaigns targeting MSM were implemented. A second survey was carried out in 2007 to assess the impact of these measures. This paper aims to examine trends in HIV and STI prevalence and in sexual behaviors between 2004 and 2007. The two surveys were conducted in four urban sites among 440 and 501 MSM--recruited using the snowball sampling method--in 2004 and 2007, respectively. A similar methodology was applied for both surveys. This consisted of a closed-ended questionnaire concerning socio-demographic, behavioral, and biomedical information plus a clinical examination including urine and blood tests to detect STIs and HIV infection. Between 2004 and 2007, the frequency of different sexual practices reported by MSM remained stable, but condom use for each type of sexual practice rose. The percentage of men who reported consistent condom use during previous-month anal sex has increased by about 35% (p<0.01). The percentage of men who reported consistent condom use during previous-month non-commercial sex with women has increased by 14% (p<0.01). HIV prevalence remained stable from 22.4% [95% CI: 18.6-26.8] in 2004 to 21.8% [95% CI: 18.3-25.7] in 2007 (adjusted OR = 1.05, p=0.8). Gonorrhea prevalence decreased from 5.5% [95% CI: 3.6-8.3] in 2004 to 2.6% [95% CI: 1.5-4.5] in 2007 (adjusted OR=0.5, p=0.07). The prevention campaigns, STI and HIV care and support programs conducted in Senegal among MSM have been followed by a reduction of risk-taking behaviors and STI prevalence among this population. Specific targeting of this group within HIV/STI prevention programs seems to be effective in decreasing sexual infections.

Evolution of malaria mortality and morbidity after the emergence of chloroquine resistance in Niakhar, Senegal.

BACKGROUND: Recently, it has been assumed that resistance of Plasmodium to chloroquine increased malaria mortality. The study aimed to assess the impact of chemoresistance on mortality attributable to malaria in a rural area of Senegal, since the emergence of resistance in 1992, whilst chloroquine was used as first-line treatment of malaria, until the change in national anti-malarial policy in 2003. METHODS: The retrospective study took place in the demographic surveillance site (DSS) of Niakhar. Data about malaria morbidity were obtained from health records of three health care facilities, where diagnosis of malaria was based on clinical signs. Source of data concerning malaria mortality were verbal autopsies performed by trained fieldworkers and examined by physicians who identified the probable cause of death. RESULTS: From 1992 to 2004, clinical malaria morbidity represented 39% of total morbidity in health centres. Mean malaria mortality was 2.4 per thousand and 10.4 per thousand among total population and children younger than five years, respectively, and was highest in the 1992-1995 period. It tended to decline from 1992 to 2003 (Trend test, total population p = 0.03, children 0-4 years p = 0.12 - children 1-4 years p = 0.04- children 5-9 years p = 0.01). CONCLUSION: Contrary to what has been observed until 1995, mortality attributable to malaria did not continue to increase dramatically in spite of the growing resistance to chloroquine and its use as first-line treatment until 2003. Malaria morbidity and mortality followed parallel trends and rather fluctuated accordingly to rainfall.

Season of birth is not associated with risk of early adult death in rural Senegal.

BACKGROUND: In a rural area of the Gambia, West Africa, young adults born in the 'hungry' season had a high excess of deaths (mortality ratios (MR): 3.7 from 14.5 years and 10.3 from 25 years, P < 0.0001). Among several potential causal factors, fetal undernutrition was considered the most plausible. This study is a similar analysis of children and young adults living in rural Senegal, close to the Gambia. METHODS: A cohort of 9192 subjects born 1962-2001 with prospectively collected dates of birth and death was analysed. MR by season of birth (July-December/January-June) was estimated using Cox's proportional hazards analysis. The nutritional status of non-pregnant women was analysed at monthly intervals 1990-1996. RESULTS: MR by season of birth was slightly greater than 1 during infancy, and close to 1 from 1-5 years and from 5-14.5 years. From 14.5 years old the MR was 0.77 (95% CI: 0.47, 1.25, P = 0.29), compared with 0.53 (95% CI: 0.28, 1.02, P = 0.056) from 20 years and 0.33 (95% CI: 0.09, 1.25, P = 0.10) from 25 years. The weight of women varied strongly by season: means were 3.0-3.9 kg lower at the end of the rainy season (September-November) than during the dry season (February-May, P < 0.001 for each year). CONCLUSIONS: This study found no increased risk of death among young adults born during the hungry season in a rural West African area despite large seasonal variations in women's nutritional status. The strongly increased risk in adult Gambians is probably not explained by fetal undernutrition.

Men who have sex with men (MSM) and factors associated with not using a condom at last sexual intercourse with a man and with a woman in Senegal.

BACKGROUND: Men who have sex with other men (MSM) are a vulnerable population in Africa that has been insufficiently explored. Given the high rate of bisexuality among MSM (73% in the past year), it is important to understand their risk-taking behaviors regarding both men and women. METHODOLOGY/PRINCIPAL FINDINGS: A socio-behavioral survey was carried out in 2007 among 501 MSM recruited using the snowball sampling method. We explore in this article why a condom was not used during last sexual intercourse with a man and with a woman, taking into account the respondent's characteristics, type of relationship and the context of the sexual act. In the survey, 489 men reported that they had had sexual intercourse at least once with another man during the previous year, and 358 with a man and with a woman. The main risk factors for not using a condom at last sexual intercourse with another man were having sex in a public place (aOR = 6.26 [95%CI: 2.71-14.46]), non-participation in an MSM prevention program (aOR = 3.47 [95%CI: 2.12-5.69]), a 19 years old or younger partner (aOR = 2.6 [95%CI: 1.23-4.53]), being 24 years or younger (aOR = 2.07 [95%CI: 1.20-3.58]) or being 35 years or over (aOR = 3.08 [95%CI:1.11-8.53]) and being unemployed (aOR = 0.36 [95%CI: 0.10-1.25]). The last sexual intercourse with the respondent's wife was hardly ever protected (2%). With women, the other factors were a 15 years or younger partner (aOR = 6.45 [95%CI: 2.56-16.28]), being educated (primary: aOR = 0.45 [95%CI: 0.21-0.95], secondary or higher: aOR = 0.26 [95%CI: 0.11-0.62]), being a student (aOR = 2.20 [95%CI: 1.07-4.54]) or unemployed (aOR = 3.72 [95%CI: 1.31-10.61]) and having participated in a MSM prevention program (aOR = 0.57 [95%CI: 0.34-0.93]). CONCLUSION: Having participated in a prevention program specifically targeting MSM constitutes a major prevention factor. However, these programs targeting MSM must address their heterosexual practices and the specific risks involved.

Early breastfeeding cessation in rural Senegal: causes, modes, and consequences.

OBJECTIVES: We studied reasons for cessation of breastfeeding before the age of 15 months, replacement feeding modes, and child mortality in West Africa. METHODS: Data were gathered for 12208 children born between 1987 and 1997 in a rural area of Senegal. Interviews were conducted with caregivers of early-weaned children, and child mortality risks were assessed. RESULTS: Fewer than 1% of children had been weaned early. The main reasons for early weaning were maternal death and new pregnancy (in 41% and 27% of cases, respectively). Twenty percent of children had been relactated by a wet nurse, and 16% had received formula. Many early-weaned children died before the age of 2 years (26%), particularly those weaned early as a result of the mother's death (hazard ratio = 5.1; 95% confidence interval [CI] = 1.74, 15.0). Girls had a lower hazard ratio than boys (0.16; 95% CI=0.05, 0.41). CONCLUSIONS: Our results showed that early cessation of breastfeeding was rare but that associated mortality was high, especially when the mother had died.

Cause-specific mortality rates in sub-Saharan Africa and Bangladesh.

OBJECTIVE: To provide internationally comparable data on the frequencies of different causes of death. METHODS: We analysed verbal autopsies obtained during 1999 -2002 from 12 demographic surveillance sites in sub-Saharan Africa and Bangladesh to find cause-specific and age-specific mortality rates. The cause-of-death codes used by the sites were harmonized to conform to the ICD-10 system, and summarized with the classification system of the Global Burden of Disease 2000 (Version 2). FINDINGS: Causes of death in the African sites differ strongly from those in Bangladesh, where there is some evidence of a health transition from communicable to noncommunicable diseases, and little malaria. HIV dominates in causes of mortality in the South African sites, which contrast with those in highly malaria endemic sites elsewhere in sub-Saharan Africa (even in neighbouring Mozambique). The contributions of measles and diarrhoeal diseases to mortality in sub-Saharan Africa are lower than has been previously suggested, while malaria is of relatively greater importance. CONCLUSION: The different patterns of mortality we identified may be a result of recent changes in the availability and effectiveness of health interventions against childhood cluster diseases.

Non-specific effects of vaccination on child survival? A prospective study in Senegal.

OBJECTIVES: Several studies have shown an association between vaccination and child mortality in developing countries. The present paper examines this issue using data from a Senegalese rural area which has been monitored from 1983 to the present. METHODS: We analysed two birth cohorts, comprising 7796 and 3573 persons who had received either BCG and DTP (diphtheria-tetanus-pertussis) simultaneously or neither of these vaccines, and who had been followed from birth to 2 years of age. The association between vaccinations and mortality was assessed by Cox proportional hazards model. RESULTS: Mortality ratios for recipients of the BCG/DTP combination were 0.59 (95% CI: 0.46-0.74) for the first cohort and 0.70 (0.50-0.97) for the second cohort. Mortality ratios for measles vaccine recipients were 0.98 (0.75-1.27) for the first cohort and 0.87 (0.57-1.30) for the second cohort. CONCLUSIONS: The BCG/DTP combination was associated with a reduction in mortality whereas measles vaccination was not associated with mortality.