Malaria transmission dynamics in Niono, Mali: the effect of the irrigation systems

The type of water management and drainage system could be a potential reason for variation in malaria transmission in rice cultivation areas. To investigate this we have compared the population dynamics of Anopheles mosquitoes (Diptera, Culicidae) in rice plots with controlled and uncontrolled water depth, i.e. casiers and hors-casiers, respectively in the Office du Niger, Mali. We also compared malaria transmission in areas with mixed and casiers plots. Larval collection was performed fortnightly with the standard WHO dipping technique. Adult Anopheles were collected both by pyrethrum spray and landing catches. During the dry season rice cultivation cycle, the larval density in the hors-casier was significantly higher than in the casier plots. The larval peak in the casier plots was considerably smaller than the one in the hors-casier. During the rainy season, no significant difference was observed between the two plot types. However, larval densities begin to rise approximately one month earlier in the casier then in the hors-casier plots, and continued to increase trough the rice development phases until the grain filling/maturation phase, declining thereafter. In contrast, in the hors-casier rice plots larval density increased throughout the rice development. This difference was not significantly reflected in the adult vector density and man biting rate. However, high relative frequencies of Anopheles funestus, survival and entomological inoculation rates of An. gambiae s.l. were observed in the mixed plot sector.     

Epidemiologic profile of women presenting to the National Hospital of Niamey,Niger for vaginal fistula repair

Objective

To describe the epidemiologic profile of women with vaginal fistulas presenting to the surgical mission trips of the International Organization for Women and Development (IOWD) at the National Hospital of Niamey, Niger.

Methods

In a cross-sectional retrospective study, data were assessed from a database of women who attended the IOWD at the National Hospital of Niamey, Niger, from October 2003 to April 2009. The database was compiled from the history and physical examination forms for each patient visit.

Results

During the study period, there were 1323 data entries and 896 initial patient visits. Overall, 580 women presented with obstetric fistulas. The median age was 29 years; the mean age at marriage was 16 years; 73.7% were married. The median age at first delivery was 18 years; the mean number of past full-term pregnancies was 3; the mean parity was 4. Vaginal (66.3%) or cesarean (27.7%) delivery was a common predisposing factor for developing an obstetric fistula. Overall, 97.4% of women labored for 24 hours or more; 75.4% delivered in hospital; 82.9% had a stillbirth.

Conclusion

Women presenting to the IOWD for fistula repair have specific epidemiologic characteristics. Better understanding of these characteristics might help to formulate future public health programs for fistula prevention.     

Patterns and prevalence of foetal anomalies in South – South Nigeria: A 2 year retrospective study using ultrasound screening

Although various rates of sonographic detection of foetal anomalies abound, no available data exist on the prevalence and patterns of anomalies in the South–South (Niger Delta) region of Nigeria. A retrospective analysis of the records of 10,440 prenatal sonograms and anomaly register over a two year period was performed. 72 foetuses were identified with a total of 88 anomalies.Anencephaly was the most common anomaly representing 23.99% (22), and achondroplasia with limb length discrepancy/dwarfism 7.95% (7). Systemic classification was as follows; CNS (42, 47.7%), urogenital (20, 22.7%), skeletal (11, 12%), GIT (9, 3.41%), others (12, 13.64%).The mean age for majority of anomalies was 25 years. A Chi-square test of significance, showed this is significantly lower than the mean age of 35 years earlier documented in literature.The study recommends a prospective screening program, use of a detailed anomaly protocol and guidelines, compulsory screening at 18–20 weeks gestational window, improved training of sonographers and use of 3D and more sophisticated equipment to improve detection rates.     

HIV seroprevalence surveys in Nigerien pregnant women: a comparison between 2002 and 2006

In the framework of HIV serosurveillance, serosurveys in pregnant women are a good alternative to population-based surveys, which are more difficult to implement. In 2002 and 2006, surveys were conducted in Niger to assess the HIV seroprevalence in pregnant women and to evaluate the trend of the HIV epidemic. The overall seroprevalence was 0.96% (95% CI 0.5-1.7%) and 1.3% (95% CI 0.9-1.8%) in 2002 and 2006, respectively, showing no significant change. In the 2006 overall sample, women living in urban areas were significantly more infected than those in rural environments, with prevalences of 1.9% and 0.7%, respectively (P=0.006). Women with higher school attainment were more often HIV-positive than other women (4.6% vs. 1.7%; P<0.001). The 2006 prevalence, which is among the lowest of the sub-Saharan region, was not significantly different from the national seroprevalence measured in adults in 2002 (0.87%, 95% CI 0.5-1.3%). Close monitoring of the epidemic must be continued.     

Variation and inheritance of oil content and fatty acid composition in niger (Guizotia abyssinica)

Niger (Guizotia abyssinica) is an economically important edible oilseed crop with a wide variation in seed oil content and fatty acid composition between populations. This study sought to determine the extent of this variation among the Ethiopian niger populations and to analyze the inheritance of high oil and oleic acid (C18:1) contents. The analysis of 153 niger populations revealed a twofold variation in seed oil content (27–56%) with 7% of the populations having more than 50% oil. These high oil content populations came from different regions and a wide altitudinal range (1400–2590 m asl). There was also a high variation in oleic acid content between populations (3.3–31.1%). Interestingly, the populations with more than 13% oleic acid were entirely collected from elevations of less than 2000 m asl. Breeding of selected genotypes for two generations revealed a highly significant positive correlation between the parents and their progenies both in oil and oleic acid contents. The study also suggests a significant contribution of environmental factors to the variation in both traits suggesting a moderate heritability. We conclude that there is a highly significant variation both in oil content and fatty acid composition in the niger populations that can be used for its improvement.     

Rotavirus Surveillance in Urban and Rural Areas of Niger,April 2010–March 2012

Knowledge of rotavirus epidemiology is necessary to make informed decisions about vaccine introduction and to evaluate vaccine impact. During April 2010–March 2012, rotavirus surveillance was conducted among 9,745 children <5 years of age in 14 hospitals/health centers in Niger, where rotavirus vaccine has not been introduced. Study participants had acute watery diarrhea and moderate to severe dehydration, and 20% of the children were enrolled in a nutrition program. Of the 9,745 children, 30.6% were rotavirus positive. Genotyping of a subset of positive samples showed a variety of genotypes during the first year, although G2P[4] predominated. G12 genotypes, including G12P[8], which has emerged as a predominant strain in western Africa, represented >80% of isolates during the second year. Hospitalization and death rates and severe dehydration among rotavirus case-patients did not differ during the 2 years. The emergence of G12P[8] warrants close attention to the characteristics of associated epidemics and possible prevention measures.     

Outbreak investigations and molecular characterization of foot‐and‐mouth disease viruses circulating in south‐west Niger

In Niger, the epidemiological situation regarding foot‐and‐mouth disease is unclear as many outbreaks are unreported. This study aimed (i) to identify Foot‐and‐mouth disease virus (FMDV ) strains currently circulating in cattle herds, and (ii) to identify risk factors associated with Foot‐and‐mouth disease (FMD )‐seropositive animals in clinical outbreaks. Epithelial tissues (n  = 25) and sera (n  = 227) were collected from cattle in eight districts of the south‐western part of Niger. Testing of clinical material revealed the presence of FMDV serotype O that was characterized within the O/WEST AFRICA topotype. The antigenic relationship between one of the FMDV isolates from Niger (O/NGR /4/2015) and three reference vaccine strains was determined by the two‐dimensional virus neutralization test (2dmVNT ), revealing a close antigenic match between the field isolate from Niger and three FMDV serotype O vaccine strains. Serological analyses using a non‐structural protein (NSP ) test provided evidence for previous FMDV infection in 70% (158/227) of the sera tested. Multivariate logistic regression analysis revealed that only the herd composition (presence of both cattle and small ruminants) was significantly associated with FMDV seropositivity as defined by NSP ‐positive results (p ‐value = .006). Of these positive sera, subsequent testing by liquid‐phase blocking ELISA (LPBE ) showed that 86% (136/158) were positive for one (or more) of four FMDV serotypes (A, O, Southern African Territories (SAT ) 1 and SAT 2). This study provides epidemiological information about FMD in the south‐western part of Niger and highlights the complex transboundary nature of FMD in Africa. These findings may help to develop effective control and preventive strategies for FMD in Niger as well, as other countries in West Africa.