Microbiota That Affect Risk for Shigellosis in Children in Low-Income Countries

Pathogens in the gastrointestinal tract exist within a vast population of microbes. We examined associations between pathogens and composition of gut microbiota as they relate to Shigella spp./enteroinvasive Escherichia coli infection. We analyzed 3,035 stool specimens (1,735 nondiarrheal and 1,300 moderate-to-severe diarrheal) from the Global Enteric Multicenter Study for 9 enteropathogens. Diarrheal specimens had a higher number of enteropathogens (diarrheal mean 1.4, nondiarrheal mean 0.95; p<0.0001). Rotavirus showed a negative association with Shigella spp. in cases of diarrhea (odds ratio 0.31, 95% CI 0.17–0.55) and had a large combined effect on moderate-to-severe diarrhea (odds ratio 29, 95% CI 3.8–220). In 4 Lactobacillus taxa identified by 16S rRNA gene sequencing, the association between pathogen and disease was decreased, which is consistent with the possibility that Lactobacillus spp. are protective against Shigella spp.–induced diarrhea. Bacterial diversity of gut microbiota was associated with diarrhea status, not high levels of the Shigella spp. ipaH gene.     

Repeated artemisinin-based combination therapies in a malaria hyperendemic area of Mali: efficacy, safety, and public health impact

Artemisinin-based combination therapies (ACTs) are the first-line treatment of uncomplicated malaria. The public health benefit and safety of repeated administration of a given ACT are poorly studied. We conducted a randomized trial comparing artemether-lumefantrine, artesunate plus amodiaquine (AS+AQ) and artesunate plus sulfadoxine-pyrimethamine (AS+SP) in patients 6 months of age and older with uncomplicated malaria in Mali from July 2005 to July 2007. The patient received the same initial treatment of each subsequent uncomplicated malaria episode except for treatment failures where quinine was used. Overall, 780 patients were included. Patients in the AS+AQ and AS+SP arms had significantly less risk of having malaria episodes; risk ratio (RR) = 0.84 (P = 0.002) and RR = 0.80 (P = 0.001), respectively. The treatment efficacy was similar and above 95% in all arms. Although all drugs were highly efficacious and well tolerated, AS+AQ and AS+SP were associated with less episodes of malaria.     

Acceptability of children's testing for HIV infection during routine care activities in the Pediatrics Department of Sourô Sanou Teaching Hospital in Bobo-Dioulasso (Burkina Faso)

Background

In order to contribute to the fight against the pediatric HIV infection, we have assessed, through a study in which we have systematically proposed to carry out children's testing, the rate of acceptability and the feasibility of children's HIV testing during the routine activities of the department. We have also analyzed the reasons for the acceptability or the refusal of the child's HIV testing by the accompanying person.

Reduced levels of T-cell subsets CD4+ and CD8+ in homozygous sickle cell anaemia patients with splenic defects

T-lymphocyte subsets were studied in two patient groups: (1) 50 patients with homozygous sickle cell anaemia (SCA) (mean age 12 (range 3-32) years old) in good health at the time of the study who showed no infectious complication. (2) 50 patients (mean age 13 (range 4-29) years old) with normal haemoglobin rate. The global response revealed a significant increase in levels of CD3+ (P=0.04) and CD8+ (P=0.04) cells when compared with the control group, there was no significant difference in levels of CD4+ cells (P=0.05) between the two groups. However, there was a relationship between T-cell subpopulation levels and spleen status. The average values of T-cell subsets (CD4+ and CD8+) in patients with SCA-induced splenic defects (asplenic, splenomegaly or splenectomized patients) were significantly reduced when compared to SCA patients with normal spleens and the control groups. These data show that T-cell activity was reduced in patients with splenic defects. A correlation between splenic status and a perturbed host defence system in patients with SCA suggests that monitoring T-cell subsets might have prognostic value in the course of sickle cell disease.     

Anti-ulcer, anti-inflammatory and antioxidant activities of the n-butanol fraction from Pteleopsis suberosa stem bark

Pteleopsis suberosa Engl. et Diels (Combretaceae) is a tree distributed in many African countries. The decoction from the stem bark is orally administered for the treatment of gastric ulcers in traditional medicine. Previous pharmacological studies reported the anti-ulcer activity of extracts from P. suberosa stem bark. In the present study, the anti-ulcer and anti-inflammatory effects of the n-butanol fraction (RBuOH) obtained from a methanol extract of P. suberosa bark were investigated on ethanol-induced gastric ulcers in rats and carrageenan-induced paw oedema in mice. Misoprostol (0.50 mg/kg, p.o.) and indomethacin (8.00 mg/kg, p.o.) were used as positive controls for anti-ulcer and anti-inflammatory activities, respectively. Results showed that RBuOH treatment significantly reduced the incidence of gastric lesions (50 mg/kg, P<0.05; 100 and 200 mg/kg, P<0.01) and restored the decreased levels of total sulfhydryl groups (T-SH) and non-protein sulfhydryl groups (NP-SH) (50, 100 mg/kg, P<0.05; 200 mg/kg, P<0.01) in the stomach homogenate. Moreover, RBuOH treatment attenuated MDA levels as index of lipid peroxidation in gastric mucosa. Administration of RBuOH at the same dosage (50, 100 and 200 mg/kg) reduced significantly (P<0.01) carrageenan-induced paw oedema in dose-dependent manner (from 42.81% to 87.81% inhibition, 5h after carrageenan injection). The anti-inflammatory effect of RBuOH at 200 mg/kg was comparable with that of indomethacin. Finally, RBuOH proved to possess elevated free radical scavenger capacity on 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay (IC(50) 23.48 microg/ml) which may contribute to the observed anti-ulcer and anti-inflammatory activities.     

Cost of integrated vector control with improved sanitation and road infrastructure coupled with the use of slow-release Bacillus sphaericus granules in a tropical urban setting

A field test of integrated vector control was conducted in a tropical urban setting with a combination of a floating, slow-release, granular formulation of Bacillus sphaericus and environmental engineering measures (renovation of roads, collective water pumps, and cesspool lids). The targets were Culex quinquefasciatus and Anopheles gambiae in the two biggest towns of Burkina Faso (West Africa). Within the intervention zone, water pumping stations were improved and the surroundings drained to prevent the accumulation of stagnant water. Roads were leveled and given either simple gutters on each side or a concrete channel on one side to drain runoff water. Garbage containers were installed to provide an alternative to the drainage channels for waste disposal. Septic tanks were modified so that they could be emptied without destroying their lid. This study showed that it is possible to implement mosquito control in a tropical urban environment with teams of young people rapidly trained to apply a biological larvicide without any tools other than an iron bar to lift cesspool lids. Environmental improvements were initially costly, but demanded little subsequent expenditure. Local inhabitants' committees were mobilized to provide people with information and monitor the efficacy of the measures. Compared with what people spent individually on mosquito prevention and malaria medicine, these measures were not expensive, but many expected the community to pay for them from existing taxes, e.g., for water treatment and disposal. The necessary funding and logistics require a municipal organization with neighborhood support, if the measures are to be effective.