Intestinal helminths as predictors of some malaria clinical outcomes and IL-1β levels in outpatients attending two public hospitals in Bamenda,North West Cameroon

This study aimed at determining the impact of intestinal helminths on malaria parasitaemia, anaemia and pyrexia considering the levels of IL-1β among outpatients in Bamenda. A cohort of 358 consented participants aged three (3) years and above, both males and females on malaria consultation were recruited in the study. At enrolment, patients’ axillary body temperatures were measured and recorded. Venous blood was collected for haemoglobin concentration and malaria parasitaemia determination. Blood plasma was used to measure human IL-1β levels using Human ELISA Kit. The Kato-Katz technique was used to process stool samples. Five species of intestinal helminths Ascaris lumbricoides (6.4%), Enterobius vermicularis (5.0%), Taenia species (4.2%), Trichuris trichiura (1.1%) and hookworms (0.8%) were identified. The overall prevalence of Plasmodium falciparum and intestinal helminths was 30.4% (109/358) and 17.6% (63/358) respectively. The prevalence of intestinal helminths in malaria patients was 17.4% (19/109). Higher Geometric mean parasite density (GMPD ±SD) (malaria parasitaemia) was significantly observed in patients co-infected with Enterobius vermicularis (5548 ± 2829/μL, p = 0.041) and with Taenia species (6799 ± 4584/μL, p = 0.020) than in Plasmodium falciparum infected patients alone (651 ± 6076/ μL). Higher parasitaemia of (1393 ± 3031/μL) and (3464 ± 2828/μL) were recorded in patients co-infected with Ascaris lumbricoides and with hookworms respectively but the differences were not significant (p > 0.05). Anaemia and pyrexia prevalence was 27.1% (97/358) and 33.5% (120/358) respectively. Malaria patients co-infected with Enterobius vermicularis and Ascaris lumbricoides had increased risk of anaemia (OR = 13.712, p = 0.002 and OR = 16.969, p = 0.014) respectively and pyrexia (OR = 18.07, p = 0.001 and OR = 22.560, p = 0.007) respectively than their counterparts. Increased levels of IL-1β were significantly observed in anaemic (148.884 ± 36.073 pg/mL, t = 7.411, p = 0.000) and pyretic (127.737 ± 50.322 pg/mL, t = 5.028, p = 0.000) patients than in non-anaemic (64.335 ± 38.995pg/mL) and apyretic patients (58.479 ± 36.194pg/mL). Malaria patients co-infected with each species of intestinal helminths recorded higher IL-1β levels (IL-1β > 121.68 ± 58.86 pg/mL) and the overall mean (139.63 ± 38.33pg/mL) was higher compared with levels in malaria (121.68 ± 58.86 pg/mL) and helminth (61.78 ± 31.69pg/mL) infected patients alone. Intestinal helminths exacerbated the clinical outcomes of malaria in the patients and increased levels of IL-1β were observed in co-infected patients with anaemia, pyrexia and higher parasitaemia.     

Treating Cattle to Protect People? Impact of Footbath Insecticide Treatment on Tsetse Density in Chad

Background

In Chad, several species of tsetse flies (Genus: Glossina ) transmit African animal trypanosomoses (AAT), which represents a major obstacle to cattle rearing, and sleeping sickness, which impacts public health. After the failure of past interventions to eradicate tsetse, the government of Chad is now looking for other approaches that integrate cost-effective intervention techniques, which can be applied by the stake holders to control tsetse-transmitted trypanosomoses in a sustainable manner. The present study thus attempted to assess the efficacy of restricted application of insecticides to cattle leg extremities using footbaths for controlling Glossina m. submorsitans, G . tachinoides and G . f . fuscipes in southern Chad.

Methodology/Principal Findings

Two sites were included, one close to the historical human African trypanosomiasis (HAT) focus of Moundou and the other to the active foci of Bodo and Moissala. At both sites, a treated and an untreated herd were compared. In the treatment sites, cattle were treated on a regular basis using a formulation of deltamethrin 0.005% (67 to 98 cattle were treated in one of the sites and 88 to 102 in the other one). For each herd, tsetse densities were monthly monitored using 7 biconical traps set along the river and beside the cattle pen from February to December 2009. The impact of footbath treatment on tsetse populations was strong (p < 10^-3) with a reduction of 80% in total tsetse catches by the end of the 6-month footbath treatment.

Conclusions/Significance

The impact of footbath treatment as a vector control tool within an integrated strategy to manage AAT and HAT is discussed in the framework of the “One Health” concept. Like other techniques based on the treatment of cattle, this technology should be used under controlled conditions, in order to avoid the development of insecticide and acaricide resistance in tsetse and tick populations, respectively.     

Selection of antimalarial drug resistance after intermittent preventive treatment of infants and children (IPTi/c) in Senegal

Senegal has since 2003 used sulphadoxine-pyrimethamine (SP) for Intermittent Preventive Treatment (IPT) of malaria in risk groups. However, the large-scale IPT strategy may result in increasing drug resistance. Our study investigated the possible impact of SP-IPT given to infants and children on the prevalence of SP-resistant haplotypes in the Plasmodium falciparum genes Pfdhfr and Pfdhps, comparing sites with and without IPTi/c. P. falciparum positives samples (n = 352) were collected from children under 5 years of age during two cross-sectional surveys in 2010 and 2011 in three health districts (two on IPTi/c and one without IPTi/c intervention) located in the southern part of Senegal. The prevalence of SP-resistance-related haplotypes in Pfdhfr and Pfdhps was determined by nested PCR followed by sequence-specific oligonucleotide probe (SSOP)–ELISA. The prevalence of the Pfdhfr double mutant haplotypes (CNRN and CICN) was stable between years at < 10% in the control group (P = 0.69), while it rose significantly in the IPTi/c group from 2% in 2010 to 20% in 2011 (P = 0.008). The prevalence of the Pfdhfr triple mutant haplotype (CIRN) increased in both groups, but only significantly in the IPTi/c group from 41% to 65% in 2011 (P = 0.005). Conversely, the Pfdhps 437G mutation decreased in both groups from 44.6% to 28.6% (P = 0.07) and from 66.7% to 47.5% (P = 0.02) between 2010 and 2011 in the control and the IPTi/c groups, respectively. Combined with Pfdhfr, there was a weak trend for decreasing prevalence of quadruple mutants (triple Pfdhfr + Pfdhps 437G) in both groups (P = 0.15 and P = 0.34). During the two cross-sectional surveys, some significant changes were observed in the SP-resistance-related genes. However, since these changes were observed in the two groups, the IPTi/c strategy does only seem to have limited impact on resistance development and other factors as well. However, continuous monitoring will be needed, due to the up-scaling of the IPTi/c strategy in Senegal according to WHO recommendations.     

Upper Limb Evaluation and One-Year Follow Up of Non-Ambulant Patients with Spinal Muscular Atrophy: An Observational Multicenter Trial

Assessment of the upper limb strength in non-ambulant neuromuscular patients remains challenging. Although potential outcome measures have been reported, longitudinal data demonstrating sensitivity to clinical evolution in spinal muscular atrophy patients are critically lacking. Our study recruited 23 non-ambulant patients, 16 patients (males/females = 6/10; median age 15.4 years with a range from 10.7 to 31.1 years) with spinal muscular atrophy type II and 7 patients (males/females = 2/5; median age 19.9 years with a range from 8.3 to 29.9 years) with type III. The Brooke functional score was on median 3 with a range from 2 to 6. The average total vital capacity was 46%, and seven patients required non-invasive ventilation at night. Patients were assessed at baseline, 6 months, and 1 year using the Motor Function Measure and innovative devices MyoGrip, MyoPinch, and MoviPlate, which assess handgrip strength, key pinch strength, and hand/finger extension-flexion function, respectively. The study demonstrated the feasibility and reliability of these measures for all patients, and sensitivity to negative changes after the age of 14 years. The younger patients showed an increase of the distal force in the follow-up period. The distal force measurements and function were correlated to different functional scales. These data represent an important step in the process of validating these devices as potential outcome measures for future clinical trials.

Trial Registration

ClinicalTrials.gov NCT00993161     

Upper Limb Strength and Function Changes during a One-Year Follow-Up in Non-Ambulant Patients with Duchenne Muscular Dystrophy: An Observational Multicenter Trial

IntroductionUpper limb evaluation of patients with Duchenne Muscular Dystrophy is crucially important to evaluations of efficacy of new treatments in non-ambulant patients. In patients who have lost ambulation, there are few validated and informative outcome measures. In addition, longitudinal data demonstrating sensitivity to clinical evolution of outcome measures over short-term periods are lacking.ResultsOur study confirmed preliminary data previously reported regarding feasibility of use and of reliability of the MyoSet and the correlation at baseline between distal strength and clinical outcomes such as FVC, Brooke score, age, and duration since loss of ambulation. A significant correlation was observed between the distal upper limb strength and clinical variables. The sensitive dynamometers (MyoGrip and MyoPinch) and MoviPlate captured a 12-month change in non-ambulant Duchenne muscular dystrophy patients of all ages.

Trial Registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT00993161","term_id":"NCT00993161"}}NCT00993161 {"type":"clinical-trial","attrs":{"text":"NCT00993161","term_id":"NCT00993161"}}NCT00993161     

Genetic Diversity within Schistosoma haematobium: DNA Barcoding Reveals Two Distinct Groups

Background

Schistosomiasis in one of the most prevalent parasitic diseases, affecting millions of people and animals in developing countries. Amongst the human-infective species S. haematobium is one of the most widespread causing urogenital schistosomiasis, a major human health problem across Africa, however in terms of research this human pathogen has been severely neglected.

Methodology/Principal Findings

To elucidate the genetic diversity of Schistosoma haematobium, a DNA ‘barcoding’ study was performed on parasite material collected from 41 localities representing 18 countries across Africa and the Indian Ocean Islands. Surprisingly low sequence variation was found within the mitochondrial cytochrome oxidase subunit I (cox1) and the NADH-dehydrogenase subunit 1 snad1). The 61 haplotypes found within 1978 individual samples split into two distinct groups; one (Group 1) that is predominately made up of parasites from the African mainland and the other (Group 2) that is made up of samples exclusively from the Indian Ocean Islands and the neighbouring African coastal regions. Within Group 1 there was a dominance of one particular haplotype (H1) representing 1574 (80%) of the samples analyzed. Population genetic diversity increased in samples collected from the East African coastal regions and the data suggest that there has been movement of parasites between these areas and the Indian Ocean Islands.

Conclusions/Significance

The high occurrence of the haplotype (H1) suggests that at some point in the recent evolutionary history of S. haematobium in Africa the population may have passed through a genetic ‘bottleneck’ followed by a population expansion. This study provides novel and extremely interesting insights into the population genetics of S. haematobium on a large geographic scale, which may have consequence for control and monitoring of urogenital schistosomiasis.     

Groundfish assemblages diversity in upwelling ecosystems: insights from the Mauritanian Exclusive Economic Zone

Upwelling ecosystems exhibit strong spatio-temporal variations of environmental conditions that drive the dynamics of marine diversity and ressources. Yet little is known in these ecosystems concerning the diversity of groundfishes. We studied the effects of environment (sea surface temperature, chlorophyll a concentration and bathymetric strata) and fishing pressure on this variability in the Mauritanian Exclusive Economic Zone (MEEZ), based on abundance data collected from 2158 hauls from scientific surveys performed on the continental shelf (15–200 m) between 1997 and 2010. First, for each haul (i.e. alpha-diversity), Species richness S and Berger Parker dominance D_bp were used as proxies of two complementary groups of nine indices, belonging to three main components of diversity (species number, evenness and taxonomic diversity), identified by a principal component analysis based on Spearman correlation coefficient. Thus the set of diversity indices used in this work suggests that a single component of diversity cannot represent the biodiversity of MEEZ groundfish. Second, generalized linear models (GLM) highlighted the stability of both indices for environmental variables, fishing effort and time, while, as shown by a previous study in the MEEZ, these variables influence species composition (i.e. beta-diversity). A longitudinal gradient of S and D_bp was highlighted, with coastal strata being richer in species and abundances more evenly distributed among species than offshore strata. Overall, this study provides a baseline of groundfish diversity in the MEEZ, that is also useful for comparison to other upwelling ecosystems, and essential for monitoring its potential shifts faced to climate change.

     

Bidirectional Introgressive Hybridization between a Cattle and Human Schistosome Species

Schistosomiasis is a disease of great medical and veterinary importance in tropical and subtropical regions, caused by parasitic flatworms of the genus Schistosoma (subclass Digenea). Following major water development schemes in the 1980s, schistosomiasis has become an important parasitic disease of children living in the Senegal River Basin (SRB). During molecular parasitological surveys, nuclear and mitochondrial markers revealed unexpected natural interactions between a bovine and human Schistosoma species: S. bovis and S. haematobium, respectively. Hybrid schistosomes recovered from the urine and faeces of children and the intermediate snail hosts of both parental species, Bulinus truncatus and B. globosus, presented a nuclear ITS rRNA sequence identical to S. haematobium, while the partial mitochondrial cox1 sequence was identified as S. bovis. Molecular data suggest that the hybrids are not 1st generation and are a result of parental and/or hybrid backcrosses, indicating a stable hybrid zone. Larval stages with the reverse genetic profile were also found and are suggested to be F1 progeny. The data provide indisputable evidence for the occurrence of bidirectional introgressive hybridization between a bovine and a human Schistosoma species. Hybrid species have been found infecting B. truncatus, a snail species that is now very abundant throughout the SRB. The recent increase in urinary schistosomiasis in the villages along the SRB could therefore be a direct effect of the increased transmission through B. truncatus. Hybridization between schistosomes under laboratory conditions has been shown to result in heterosis (higher fecundity, faster maturation time, wider intermediate host spectrum), having important implications on disease prevalence, pathology and treatment. If this new hybrid exhibits the same hybrid vigour, it could develop into an emerging pathogen, necessitating further control strategies in zones where both parental species overlap.     

Bottlenecks for High Coverage of Intermittent Preventive Treatment in Pregnancy: The Case of Adolescent Pregnancies in Rural Burkina Faso

Background

While IPTp-SP is currently being scaled up in sub-Saharan Africa (SSA), the coverage with the required ≥2 doses of SP remains considerably short of the Roll Back Malaria (RBM) goal of 80%, not to mention of the recently advocated universal coverage.

Methods

The study triangulates quantitative data from a health center randomized community-based trial on IPTp-SP effectiveness and the additional benefit of a promotional campaign with qualitative data from focused ethnography.

Findings

In rural Burkina Faso, despite the significantly higher risk of malaria infection among adolescent primigravidae (PG) (OR 2.44 95%CI 1.81–3.28, p<0.001), making them primary target beneficiaries of IPTp-SP, adolescents adhered to the required three or more ANC visits significantly less (PG: 46.6%; SG 43.7%) than adults (PG: 61.9%; SG 54.9%) and had lower SP uptake during the malaria transmission season, further showing the difficulty of reaching this age group. Adolescents'' structural constraints (such as their social position and household labor requirements) and needs (such as anonymity in the health encounter) leave them highly vulnerable during their pregnancies and, especially, during the high malaria transmission season.

Conclusion

Our study shows that adolescents need to be targeted specifically, prior to their first pregnancy and with measures adapted to their social context, addressing their structural constraints and needs and going beyond standard health promotion campaigns. Unless such specific measures are taken, adolescents'' social vulnerability will present a serious bottleneck for the effectiveness of IPTi-SP.