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Dabis F, Msellati P, Meda N, Welffens-Ekra C, You B, Manigart O, Leroy V, Simonon A, Cartoux M, Combe P, Ouangré A, Ramon R, Ky-Zerbo O, Montcho C, Salamon R, Rouzioux C, Van de Perre P, Mandelbrot L. 6-month efficacy, tolerance, and acceptability of a short regimen of oral zidovudine to reduce vertical transmission of HIV in breastfed children in Côte d'Ivoire and Burkina Faso: a double-blind placebo-controlled multicentre trial. DITRAME Study Group. DIminution de la Transmission Mère-Enfant. Lancet 1999; 353:786-92. [PMID: 10459959 DOI: 10.1016/s0140-6736(98)11046-2] [Citation(s) in RCA: 374] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Zidovudine reduces the rate of vertical transmission of HIV in non-breastfed populations. We assessed the acceptability, tolerance, and 6-month efficacy of a short regimen of oral zidovudine in African populations practising breastfeeding. METHODS A randomised double-blind placebo-controlled trial was carried out in public clinics of Abidjan, Côte d'Ivoire, and Bobo-Dioulasso, Burkina Faso. Eligible participants were women aged 18 years or older, who had confirmed HIV-1 infection and pregnancy of 36-38 weeks duration, and who gave written informed consent. Exclusion criteria were severe anaemia, neutropenia, abnormal liver function, and sickle-cell disease. Women were randomly assigned zidovudine (n=214; 300 mg twice daily until labour, 600 mg at beginning of labour, and 300 mg twice daily for 7 days post partum) or matching placebo (n=217). The primary outcome was the diagnosis of HIV-1 infection in the infant on the basis of sequential DNA PCR tests at days 1-8, 45, 90, and 180. We compared the probability of infection at a given age in the two groups. Analyses were by intention to treat. FINDINGS Women were enrolled between September, 1995, and February, 1998, when enrolment to the placebo group was stopped. Analysis was based on 421 women and 400 lifeborn infants. Baseline demographic, clinical, and laboratory characteristics were similar in the two groups. The Kaplan-Meier probability of HIV infection in the infant at 6 months was 18.0% in the zidovudine group (n=192) and 27.5% in the placebo group (n=197; relative efficacy 0.38 [95% CI 0.05-0.60]; p=0.027). Adjustment for centre, period of recruitment, mode of delivery, maternal CD4-cell count, duration of labour, prolonged rupture of membranes, and duration of breastfeeding did not change the treatment effect. The proportions of women taking more than 80% of the planned maximum dose were 75% before delivery, 81% during labour, and 83% post partum, without statistical difference between the groups. No major adverse biological or clinical event was reported in excess among women and children of the zidovudine group. INTERPRETATION A short course of oral zidovudine given during the peripartum period is well accepted and well tolerated, and provides a 38% reduction in early vertical transmission of HIV-1 infection despite breastfeeding.
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Clinical Trial |
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374 |
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Modiano D, Petrarca V, Sirima BS, Nebié I, Diallo D, Esposito F, Coluzzi M. Different response to Plasmodium falciparum malaria in west African sympatric ethnic groups. Proc Natl Acad Sci U S A 1996; 93:13206-11. [PMID: 8917569 PMCID: PMC24071 DOI: 10.1073/pnas.93.23.13206] [Citation(s) in RCA: 160] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The comparison of malaria indicators among populations that have different genetic backgrounds and are uniformly exposed to the same parasite strains is one approach to the study of human heterogeneties in the response to the infection. We report the results of comparative surveys on three sympatric West African ethnic groups, Fulani, Mossi, and Rimaibé, living in the same conditions of hyperendemic transmission in a Sudan savanna area northeast of Ouagadougou, Burkina Faso. The Mossi and Rimaibé are Sudanese negroid populations with a long tradition of sedentary farming, while the Fulani are nomadic pastoralists, partly settled and characterized by non-negroid features of possible caucasoid origin. Parasitological, clinical, and immunological investigations showed consistent interethnic differences in Plasmodium falciparum infection rates, malaria morbidity, and prevalence and levels of antibodies to various P. falciparum antigens. The data point to a remarkably similar response to malaria in the Mossi and Rimaibé, while the Fulani are clearly less parasitized, less affected by the disease, and more responsive to all antigens tested. No difference in the use of malaria protective measures was demonstrated that could account for these findings, and sociocultural or environmental factors do not seem to be involved. Known genetic factors of resistance to malaria did not show higher frequencies in the Fulani. The differences in the immune response were not explained by the entomological observations, which indicated substantially uniform exposure to infective bites. The available data support the existence of unknown genetic factors, possibly related to humoral immune responses, determining interethnic differences in the susceptibility to malaria.
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research-article |
29 |
160 |
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Gonçalves BP, Kapulu MC, Sawa P, Guelbéogo WM, Tiono AB, Grignard L, Stone W, Hellewell J, Lanke K, Bastiaens GJH, Bradley J, Nébié I, Ngoi JM, Oriango R, Mkabili D, Nyaurah M, Midega J, Wirth DF, Marsh K, Churcher TS, Bejon P, Sirima SB, Drakeley C, Bousema T. Examining the human infectious reservoir for Plasmodium falciparum malaria in areas of differing transmission intensity. Nat Commun 2017; 8:1133. [PMID: 29074880 PMCID: PMC5658399 DOI: 10.1038/s41467-017-01270-4] [Citation(s) in RCA: 149] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Accepted: 09/05/2017] [Indexed: 12/20/2022] Open
Abstract
A detailed understanding of the human infectious reservoir is essential for improving malaria transmission-reducing interventions. Here we report a multi-regional assessment of population-wide malaria transmission potential based on 1209 mosquito feeding assays in endemic areas of Burkina Faso and Kenya. Across both sites, we identified 39 infectious individuals. In high endemicity settings, infectious individuals were identifiable by research-grade microscopy (92.6%; 25/27), whilst one of three infectious individuals in the lowest endemicity setting was detected by molecular techniques alone. The percentages of infected mosquitoes in the different surveys ranged from 0.05 (4/7716) to 1.6% (121/7749), and correlate positively with transmission intensity. We also estimated exposure to malaria vectors through genetic matching of blood from 1094 wild-caught bloodfed mosquitoes with that of humans resident in the same houses. Although adults transmitted fewer parasites to mosquitoes than children, they received more mosquito bites, thus balancing their contribution to the infectious reservoir.
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research-article |
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149 |
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Müller O, Traoré C, Becher H, Kouyaté B. Malaria morbidity, treatment-seeking behaviour, and mortality in a cohort of young children in rural Burkina Faso. Trop Med Int Health 2003; 8:290-6. [PMID: 12667146 DOI: 10.1046/j.1365-3156.2003.01030.x] [Citation(s) in RCA: 125] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To describe the pattern of fever-associated morbidity, treatment-seeking behaviour for fever episodes, and cause-specific mortality in young children of a malaria-holoendemic area in rural Burkina Faso. METHODS In a longitudinal community-based intervention study, 709 representative children aged 6-31 months were followed daily over 6 months (including the main malaria transmission period) through village-based field staff. RESULTS Of 1848 disease episodes, 1640 (89%) were fever episodes, and of those, 894 (55%) were attributed to malaria (fever + > or =5000 parasites/microl). Eighty-five percent of fever episodes were treated, mainly with chloroquine and paracetamol, 69% of treatments took place in households, 16% in local health centres, 13% in villages, and 1% in hospitals. Treatment-seeking in a health centre or hospital was associated with accessibility and disease severity. Cerebral malaria and malnutrition-associated diarrhoea were the most frequently diagnosed causes of death. While most children with a post-mortem diagnosis of diarrhoea had not received any treatment, children who died of malaria had often received insufficient treatment. In particular, there was a lack of an appropriate second-line treatment at formal health services after chloroquine treatment had failed to resolve symptoms. CONCLUSIONS These findings call for more effective prevention and treatment of malaria, malnutrition and diarrhoea in rural African communities, as well as for better supervision of existing malaria treatment guidelines in formal health services.
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125 |
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Chandramohan D, Zongo I, Sagara I, Cairns M, Yerbanga RS, Diarra M, Nikièma F, Tapily A, Sompougdou F, Issiaka D, Zoungrana C, Sanogo K, Haro A, Kaya M, Sienou AA, Traore S, Mahamar A, Thera I, Diarra K, Dolo A, Kuepfer I, Snell P, Milligan P, Ockenhouse C, Ofori-Anyinam O, Tinto H, Djimde A, Ouédraogo JB, Dicko A, Greenwood B. Seasonal Malaria Vaccination with or without Seasonal Malaria Chemoprevention. N Engl J Med 2021; 385:1005-1017. [PMID: 34432975 DOI: 10.1056/nejmoa2026330] [Citation(s) in RCA: 121] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Malaria control remains a challenge in many parts of the Sahel and sub-Sahel regions of Africa. METHODS We conducted an individually randomized, controlled trial to assess whether seasonal vaccination with RTS,S/AS01E was noninferior to chemoprevention in preventing uncomplicated malaria and whether the two interventions combined were superior to either one alone in preventing uncomplicated malaria and severe malaria-related outcomes. RESULTS We randomly assigned 6861 children 5 to 17 months of age to receive sulfadoxine-pyrimethamine and amodiaquine (2287 children [chemoprevention-alone group]), RTS,S/AS01E (2288 children [vaccine-alone group]), or chemoprevention and RTS,S/AS01E (2286 children [combination group]). Of these, 1965, 1988, and 1967 children in the three groups, respectively, received the first dose of the assigned intervention and were followed for 3 years. Febrile seizure developed in 5 children the day after receipt of the vaccine, but the children recovered and had no sequelae. There were 305 events of uncomplicated clinical malaria per 1000 person-years at risk in the chemoprevention-alone group, 278 events per 1000 person-years in the vaccine-alone group, and 113 events per 1000 person-years in the combination group. The hazard ratio for the protective efficacy of RTS,S/AS01E as compared with chemoprevention was 0.92 (95% confidence interval [CI], 0.84 to 1.01), which excluded the prespecified noninferiority margin of 1.20. The protective efficacy of the combination as compared with chemoprevention alone was 62.8% (95% CI, 58.4 to 66.8) against clinical malaria, 70.5% (95% CI, 41.9 to 85.0) against hospital admission with severe malaria according to the World Health Organization definition, and 72.9% (95% CI, 2.9 to 92.4) against death from malaria. The protective efficacy of the combination as compared with the vaccine alone against these outcomes was 59.6% (95% CI, 54.7 to 64.0), 70.6% (95% CI, 42.3 to 85.0), and 75.3% (95% CI, 12.5 to 93.0), respectively. CONCLUSIONS Administration of RTS,S/AS01E was noninferior to chemoprevention in preventing uncomplicated malaria. The combination of these interventions resulted in a substantially lower incidence of uncomplicated malaria, severe malaria, and death from malaria than either intervention alone. (Funded by the Joint Global Health Trials and PATH; ClinicalTrials.gov number, NCT03143218.).
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Comparative Study |
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121 |
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Rihet P, Traoré Y, Abel L, Aucan C, Traoré-Leroux T, Fumoux F. Malaria in humans: Plasmodium falciparum blood infection levels are linked to chromosome 5q31-q33. Am J Hum Genet 1998; 63:498-505. [PMID: 9683598 PMCID: PMC1377308 DOI: 10.1086/301967] [Citation(s) in RCA: 113] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Plasmodium falciparum malaria remains a major cause of morbidity and mortality in many tropical countries, especially those in sub-Saharan Africa. Human genetic control of malaria infection is poorly understood; in particular, genes controlling P. falciparum blood infection levels remain to be identified. We recently evidenced the existence of complex genetic factors controlling blood infection levels in an urban population living in Burkina Faso. We performed, on 153 sibs from 34 families, sib-pair linkage analyses between blood infection levels and chromosome 5q31-q33, which contains numerous candidate genes encoding immunological molecules. Our results, obtained by means of the two-point Haseman-Elston (HE) method and a nonparametric (NP) approach, show linkage of parasitemia to D5S393 (P=.002) and D5S658 (P=.0004). Multipoint analyses confirmed linkage, with a peak close to D5S658 (P=.0013 and P=.0007 with the HE and NP methods, respectively). The heritability of the locus was .48, according to the two-point results, and .43, according to the multipoint results; this indicates that its variation accounted for approximately 45% of the variance of blood infection levels and that the locus plays a central role in the control of parasitemia. The identification of the gene is, therefore, of major interest in understanding the mechanisms controlling P. falciparum parasitemia.
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research-article |
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113 |
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Parent du Châtelet I, Traore Y, Gessner BD, Antignac A, Naccro B, Njanpop-Lafourcade BM, Ouedraogo MS, Tiendrebeogo SR, Varon E, Taha MK. Bacterial Meningitis in Burkina Faso: Surveillance Using Field-Based Polymerase Chain Reaction Testing. Clin Infect Dis 2005; 40:17-25. [PMID: 15614687 DOI: 10.1086/426436] [Citation(s) in RCA: 108] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2004] [Accepted: 08/10/2004] [Indexed: 11/04/2022] Open
Abstract
BACKGROUND In addition to frequent epidemics of group A meningococcal disease, endemic bacterial meningitis due mostly to Neisseria meningitidis, pneumococcus, and Haemophilus influenzae type b is a serious problem in sub-Saharan Africa. The improved ability to identify the etiologic agent in cases of bacterial meningitis will facilitate more rapid administration of precise therapy. METHODS To describe the epidemiology of bacterial meningitis and evaluate the usefulness of field-based polymerase chain reaction (PCR) testing, we implemented population-based meningitis surveillance in Burkina Faso during 2002-2003 by use of PCR, culture, and antigen detection tests. RESULTS Among persons aged 1 month to 67 years, the incidences of meningococcal meningitis, pneumococcal meningitis, and Haemophilus influenzae type b meningitis were 19 cases (n=179), 17 cases (n=162), and 7.1 cases (n=68) per 100,000 persons per year, respectively. Of the cases of meningococcal meningitis, 72% were due to N. meningitidis serogroup W135. Pneumococcal meningitis caused 61% of deaths and occurred in a seasonal pattern that was similar to that of meningococcal meningitis. Of cases of pneumococcal meningitis and N. meningitidis serogroup W135 meningitis, 71% occurred among persons >2 years of age. Most patients, regardless of the etiology of their illness and the existence of an epidemic, received short-course therapy with oily chloramphenicol. Compared with culture as the gold standard, the sensitivity and specificity of PCR in the field were high; this result was confirmed in Burkina Faso and Paris. CONCLUSIONS Precise and rapid identification of etiologic agents is critical for improvement in the treatment and prevention of meningitis, and, thus, PCR should be considered for wider use in Africa. Vaccines against Streptococcus pneumoniae, N. meningitidis (including serogroup W135), and H. influenzae type b all will have a major impact on the bacterial meningitis burden. Antibiotic recommendations need to consider the importance of S. pneumoniae, even during the epidemic season.
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MESH Headings
- Adolescent
- Adult
- Aged
- Burkina Faso/epidemiology
- Child
- Child, Preschool
- Haemophilus influenzae type b/isolation & purification
- Humans
- Incidence
- Infant
- Meningitis, Bacterial/epidemiology
- Meningitis, Bacterial/mortality
- Meningitis, Bacterial/prevention & control
- Meningitis, Haemophilus/diagnosis
- Meningitis, Haemophilus/epidemiology
- Meningitis, Haemophilus/prevention & control
- Meningitis, Meningococcal/diagnosis
- Meningitis, Meningococcal/epidemiology
- Meningitis, Meningococcal/prevention & control
- Meningitis, Pneumococcal/diagnosis
- Meningitis, Pneumococcal/epidemiology
- Meningitis, Pneumococcal/prevention & control
- Middle Aged
- Neisseria meningitidis/isolation & purification
- Polymerase Chain Reaction/methods
- Population Surveillance
- Quality Control
- Sensitivity and Specificity
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108 |
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Schoeps A, Gabrysch S, Niamba L, Sié A, Becher H. The effect of distance to health-care facilities on childhood mortality in rural Burkina Faso. Am J Epidemiol 2011; 173:492-8. [PMID: 21262911 DOI: 10.1093/aje/kwq386] [Citation(s) in RCA: 106] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
This study aims to investigate the relation between distance to health facilities, measured as continuous travel time, and mortality among infants and children younger than 5 years of age in rural Burkina Faso, an area with low health facility density. The study included 24,555 children born between 1993 and 2005 in the Nouna Health and Demographic Surveillance System. The average walking time from each village to the closest health facility was obtained for both the dry and the rainy season, and its effect on infant (<1 year), child (1-4 years), and under-5 mortality overall was analyzed by Cox regression. The authors observed 3,426 childhood deaths, corresponding to a 5-year survival of 85%. Walking distance was significantly related to both infant and child mortality, although the shape of this effect varied distinctly between the 2 age groups. Overall, under-5 mortality, adjusted for confounding, was more than 50% higher at a distance of 4 hours compared with having a health facility in the village (P < 0.0001, 2 sided). The region of residence was an additional determinant for under-5 mortality. The findings of this study emphasize the importance of geographic accessibility of health care for child survival in sub-Saharan Africa and demonstrate the need to improve health-care access to achieve the Millennium Development Goals.
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Multicenter Study |
14 |
106 |
9
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Koukounari A, Gabrielli AF, Toure S, Bosque-Oliva E, Zhang Y, Sellin B, Donnelly CA, Fenwick A, Webster JP. Schistosoma haematobium infection and morbidity before and after large-scale administration of praziquantel in Burkina Faso. J Infect Dis 2007; 196:659-69. [PMID: 17674306 DOI: 10.1086/520515] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2006] [Accepted: 02/22/2007] [Indexed: 11/03/2022] Open
Abstract
BACKGROUND In sub-Saharan Africa, 112 million people are infected with Schistosoma haematobium, with the most intense infections in children 5-15 years old. METHODS We describe a longitudinal epidemiological study that evaluates the relationship between S. haematobium infection and associated morbidity in children before and after the large-scale administration of praziquantel for schistosomiasis and albendazole for soil-transmitted helminths. RESULTS At baseline, higher intensities of S. haematobium infection were observed in children with anemia and/or severe microhematuria, but there was no apparent association between the risk of undernutrition and intensity of S. haematobium infection. Significant reductions in the prevalence and intensity of S. haematobium infection 1 year after treatment were, however, observed. Children who benefited the most from anthelmintic treatment in terms of increased hemoglobin concentrations were those who had anemia at baseline and those with highly positive microhematuria scores at baseline. CONCLUSIONS This study suggests that even a single round of mass chemotherapy can have a substantial impact on S. haematobium infection and its associated morbidity in children.
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Research Support, Non-U.S. Gov't |
18 |
105 |
10
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Collenberg E, Ouedraogo T, Ganamé J, Fickenscher H, Kynast-Wolf G, Becher H, Kouyaté B, Kräusslich HG, Sangaré L, Tebit DM. Seroprevalence of six different viruses among pregnant women and blood donors in rural and urban Burkina Faso: A comparative analysis. J Med Virol 2006; 78:683-92. [PMID: 16555290 DOI: 10.1002/jmv.20593] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
A seroprevalence study was carried out of six different human pathogenic viruses, namely human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), human T-cell leukemia virus (HTLV), human herpesvirus type 8 (HHV-8), and dengue virus among pregnant women and blood donors from rural (Nouna) and urban (Ouagadougou) Burkina Faso, West Africa. A total of 683 samples from blood donors (n = 191) and pregnant women (n = 492) were collected from both sites and screened for the different virus infection markers resulting in the following prevalence values for Nouna or Ouagadougou, respectively: HIV 3.6/4.6, anti-HBV core (anti-HBc) 69.6/76.4, HBV surface antigen (HBsAg)14.3/17.3, HCV 2.2/1.5, HTLV 1.4/0.5, HHV-8 11.5/13.5, dengue virus 26.3/36.5. Individuals aged > or =25 years were more likely to be infected with HIV than those below 24 years (P < 0.05). Infection with HIV increased the likelihood of co-infection with other viruses, such as HHV-8, HBV and HTLV. Co-infection studies involving five viruses (HBV-HBsAg, HHV-8, HIV, HCV, and HTLV) showed that 4.8% (33/683) of the studied population were dually infected, with HBsAg+ HHV-8 (13/33), HBsAg+HIV (8/33) and HIV+HHV-8 (8/33) being the most common co-infections. Of the population studied 0.6% (4/683) was triply infected, the most common infection being with HBV+HIV+HHV-8 (3/4). There was no difference in the prevalence of HIV, anti-HBc, HBsAg, HCV, HTLV, and HHV-8 either among blood donors or pregnant women in urban or rural setting, while dengue virus prevalence was relatively lower in rural (26.3%) than in urban (36.5%) Burkina Faso.
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Research Support, Non-U.S. Gov't |
19 |
105 |
11
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Delrieu I, Yaro S, Tamekloé TAS, Njanpop-Lafourcade BM, Tall H, Jaillard P, Ouedraogo MS, Badziklou K, Sanou O, Drabo A, Gessner BD, Kambou JL, Mueller JE. Emergence of epidemic Neisseria meningitidis serogroup X meningitis in Togo and Burkina Faso. PLoS One 2011; 6:e19513. [PMID: 21625480 PMCID: PMC3098835 DOI: 10.1371/journal.pone.0019513] [Citation(s) in RCA: 104] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2011] [Accepted: 03/31/2011] [Indexed: 11/19/2022] Open
Abstract
Serogroup X meningococci (NmX) historically have caused sporadic and clustered meningitis cases in sub-Saharan Africa. To study recent NmX epidemiology, we analyzed data from population-based, sentinel and passive surveillance, and outbreak investigations of bacterial meningitis in Togo and Burkina Faso during 2006–2010. Cerebrospinal fluid specimens were analyzed by PCR. In Togo during 2006–2009, NmX accounted for 16% of the 702 confirmed bacterial meningitis cases. Kozah district experienced an NmX outbreak in March 2007 with an NmX seasonal cumulative incidence of 33/100,000. In Burkina Faso during 2007–2010, NmX accounted for 7% of the 778 confirmed bacterial meningitis cases, with an increase from 2009 to 2010 (4% to 35% of all confirmed cases, respectively). In 2010, NmX epidemics occurred in northern and central regions of Burkina Faso; the highest district cumulative incidence of NmX was estimated as 130/100,000 during March–April. Although limited to a few districts, we have documented NmX meningitis epidemics occurring with a seasonal incidence previously only reported in the meningitis belt for NmW135 and NmA, which argues for development of an NmX vaccine.
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Research Support, Non-U.S. Gov't |
14 |
104 |
12
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Nebié Y, Meda N, Leroy V, Mandelbrot L, Yaro S, Sombié I, Cartoux M, Tiendrébeogo S, Dao B, Ouangré A, Nacro B, Fao P, Ky-Zerbo O, Van de Perre P, Dabis F. Sexual and reproductive life of women informed of their HIV seropositivity: a prospective cohort study in Burkina Faso. J Acquir Immune Defic Syndr 2001; 28:367-72. [PMID: 11707674 DOI: 10.1097/00126334-200112010-00010] [Citation(s) in RCA: 102] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND In the context of the DITRAME-ANRS 049 research program that evaluated interventions aimed at reducing mother-to-child transmission of HIV (MTCT) in Bobo-Dioulasso (Burkina Faso), Voluntary HIV counseling and testing (VCT) services were established for pregnant women. HIV-infected women were advised to disclose their HIV serostatus to their male partners who were also offered VCT, to use condoms to reduce sexual transmission, and to choose an effective contraception method to avoid unwanted pregnancies. This study aimed at assessing how HIV test results were shared with male sexual partners, the level of use of modern contraceptive methods, and the pregnancy incidence among these women informed of the risks surrounding sexual and reproductive health during HIV infection. METHODS From 1995 to 1999, a quarterly prospective follow-up of a cohort of HIV-positive women. RESULTS Overall, 306 HIV-positive women were monitored over an average period of 13.5 months following childbirth, accounting for a total of 389 person-years. The mean age at enrollment in the cohort was 25.1 (standard deviation, 5.2 years). In all, 18% of women informed their partners, 8% used condoms at each instance of sexual intercourse to avoid HIV transmission, and 39% started using hormonal contraception. A total of 48 pregnancies occurred after HIV infection was diagnosed, an incidence of 12.3 pregnancies per 100 person-years. Pregnancy incidence was 4 per 100 person-years in the first year of monitoring and this rose significantly to 18 per 100 person-years in the third year. The only predictor of the occurrence of a pregnancy after HIV diagnosis was the poor outcome of the previous pregnancy (stillbirth, infant death). Severe immunodeficiency and change in marital status were the only factors that prevented the occurrence of a pregnancy after HIV diagnosis. CONCLUSION Our study shows a poor rate of HIV test sharing and a poor use of contraceptive methods despite regular advice and counseling. Pregnancy incidence remained comparable with the pregnancy rate in the general population. To improve this situation, approaches for involving husbands or partners in VCT and prevention of MTCT interventions should be developed, evaluated, and implemented.
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102 |
13
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Yaro S, Lourd M, Traoré Y, Njanpop-Lafourcade BM, Sawadogo A, Sangare L, Hien A, Ouedraogo MS, Sanou O, Parent du Châtelet I, Koeck JL, Gessner BD. Epidemiological and molecular characteristics of a highly lethal pneumococcal meningitis epidemic in Burkina Faso. Clin Infect Dis 2006; 43:693-700. [PMID: 16912941 DOI: 10.1086/506940] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2006] [Accepted: 04/17/2006] [Indexed: 11/03/2022] Open
Abstract
BACKGROUND Public health and clinical strategies for meningitis epidemics in sub-Saharan Africa usually assume that Neisseria meningitidis infection causes most disease. METHODS During 24 months from 2002 to 2005, we collected clinical and laboratory information for suspected acute bacterial meningitis cases from 3 districts in Burkina Faso. Streptococcus pneumoniae was identified by culture, polymerase chain reaction, or antigen detection in cerebrospinal fluid. Pneumococcal genotyping was performed on strains using multilocus variable-number tandem repeat typing and multilocus sequence typing. RESULTS Samples of cerebrospinal fluid were collected from 1686 persons; 249 (15%) had S. pneumoniae identified (annual incidence, 14 cases per 100,000 persons). Of these patients, 115 (46%) died, making S. pneumoniae the most commonly identified organism and responsible for two-thirds of deaths due to bacterial meningitis. During the meningitis epidemic season, an average of 38 cases of S. pneumoniae infection were identified each month, compared with an average of 8.7 cases during other months. Of 48 pneumococci that were tested, 21 (44%) were identified as serotype 1, and the remaining 27 (56%) were identified as 15 different serogroups and/or serotypes. Both serotype 1 and other serogroups and/or serotypes were seasonal. The genotypes of serotype 1 isolates were closely related but diversified over the study period and were similar to, but not identical to, the predominant genotypes found previously in Ghana. CONCLUSIONS Intervention strategies during the epidemic season in Burkina Faso (and perhaps elsewhere) must now account for pneumococcal meningitis occurring in an epidemic pattern similar to meningococcal meningitis. Although a serotype 1 clone was commonly isolated, over half of the cases were caused by other serogroups and/or serotypes, and genetic diversification increased over a relatively short period.
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Research Support, Non-U.S. Gov't |
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100 |
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Ducatez MF, Olinger CM, Owoade AA, Tarnagda Z, Tahita MC, Sow A, De Landtsheer S, Ammerlaan W, Ouedraogo JB, Osterhaus ADME, Fouchier RAM, Muller CP. Molecular and antigenic evolution and geographical spread of H5N1 highly pathogenic avian influenza viruses in western Africa. J Gen Virol 2007; 88:2297-2306. [PMID: 17622635 DOI: 10.1099/vir.0.82939-0] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In Africa, highly pathogenic avian influenza H5N1 virus was first detected in northern Nigeria and later also in other regions of the country. Since then, seven other African countries have reported H5N1 infections. This study reports a comparison of full-length genomic sequences of H5N1 isolates from seven chicken farms in Nigeria and chicken and hooded vultures in Burkina Faso with earlier H5N1 outbreaks worldwide. In addition, the antigenicity of Nigerian H5N1 isolates was compared with earlier strains. All African strains clustered within three sublineages denominated A (south-west Nigeria, Niger), B (south-west Nigeria, Egypt, Djibouti) and C (northern Nigeria, Burkina Faso, Sudan, Côte d'Ivoire), with distinct nucleotide and amino acid signatures and distinct geographical distributions within Africa. Probable non-African ancestors within the west Asian/Russian/European lineage distinct from the south-east Asian lineages were identified for each sublineage. All reported human cases in Africa were caused by sublineage B. Substitution rates were calculated on the basis of sequences from 11 strains from a single farm in south-west Nigeria. As H5N1 emerged essentially at the same time in the north and south-west of Nigeria, the substitution rates confirmed that the virus probably did not spread from the north to the south, given the observed sequence diversity, but that it entered the country via three independent introductions. The strains from Burkina Faso seemed to originate from northern Nigeria. At least two of the sublineages also circulated in Europe in 2006 as seen in Germany, further suggesting that the sublineages had already emerged outside of Africa and seemed to have followed the east African/west Asian and Black Sea/Mediterranean flyways of migratory birds.
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Research Support, Non-U.S. Gov't |
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95 |
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Costantini C, Sagnon NF, della Torre A, Diallo M, Brady J, Gibson G, Coluzzi M. Odor-mediated host preferences of West African mosquitoes, with particular reference to malaria vectors. Am J Trop Med Hyg 1998; 58:56-63. [PMID: 9452293 DOI: 10.4269/ajtmh.1998.58.56] [Citation(s) in RCA: 93] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The role of odors in mosquito host preferences was studied in a village near Ouagadougou, Burkina Faso. Two odor-baited entry-traps were put beside one another and a choice of host odor-laden air was blown out of them. Odors of a human and a calf (of similar mass) were drawn from two tents in which each was separately concealed. Allowances were made for trap position, differences in human-subject attractiveness, CO2 levels, and trap contamination with alternative host odors. Choices for the human-baited trap greater than the 0.5 random expectation were made by Anopheles gambiae s.l. (0.96) and An. pharoensis (0.68). The choices for the human-baited trap of Culex antennatus were significantly lower than 0.5 (0.25), whereas for the Cx. decens species group (0.56), the difference was not significant. Interpretation of the latter result was complicated by the significant effect of CO2 levels on the index. Species caught in low numbers but whose trap distribution showed a bias towards the human-baited trap were An. funestus (total numbers in the human-baited trap to the calf-baited trap = 9:0), Mansonia africana (17: 1), Aedes dalzieli (22:4), and Ae. hirsutus (13:1); species showing bias towards the calf-baited trap were An. rufipes (0:11), Cx. duttoni (0:17), and Cx. nebulosus (2:35). Mansonia uniformis was the only species distributed randomly between the two traps. Molecular identification of the An. gambiae s.l. samples revealed a marked difference in trap distribution: for the human-baited trap the ratio was 52% An. arabiensis to 48% An. gambiae s.s.; for the calf-baited trap, it was 92% An. arabiensis to 8% An. gambiae s.s.
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Didelot-Rousseau MN, Nagot N, Costes-Martineau V, Vallès X, Ouedraogo A, Konate I, Weiss HA, Van de Perre P, Mayaud P, Segondy M. Human papillomavirus genotype distribution and cervical squamous intraepithelial lesions among high-risk women with and without HIV-1 infection in Burkina Faso. Br J Cancer 2006; 95:355-62. [PMID: 16832413 PMCID: PMC2360631 DOI: 10.1038/sj.bjc.6603252] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Human papillomavirus (HPV) infection and cervical squamous intraepithelial lesions (SILs) were studied in 379 high-risk women. Human papillomavirus DNA was detected in 238 of 360 (66.1%) of the beta-globin-positive cervical samples, and 467 HPV isolates belonging to 35 types were identified. Multiple (2-7 types) HPV infections were observed in 52.9% of HPV-infected women. The most prevalent HPV types were HPV-52 (14.7%), HPV-35 (9.4%), HPV-58 (9.4%), HPV-51 (8.6%), HPV-16 (7.8%), HPV-31 (7.5%), HPV-53 (6.7%), and HPV-18 (6.4%). Human immunodeficiency virus type 1 (HIV-1) seroprevalence was 36.0%. Human papillomavirus prevalence was significantly higher in HIV-1-infected women (87 vs 54%, prevalence ratio (PR) = 1.61, 95% confidence interval (CI): 1.4-1.8). High-risk HPV types (71 vs 40%, PR = 1.79, 95% CI: 1.5-2.2), in particular HPV-16+18 (22 vs 9%, PR = 2.35, 95% CI: 1.4-4.0), and multiple HPV infections (56 vs 23%, PR = 2.45, 95% CI: 1.8-3.3) were more prevalent in HIV-1-infected women. High-grade SIL (HSIL) was identified in 3.8% of the women. Human immunodeficiency virus type 1 infection was strongly associated with presence of HSIL (adjusted odds ratio = 17.0; 95% CI 2.2-134.1, P = 0.007) after controlling for high-risk HPV infection and other risk factors for HSIL. Nine of 14 (63%) HSIL cases were associated with HPV-16 or HPV-18 infection, and might have been prevented by an effective HPV-16/18 vaccine.
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Research Support, Non-U.S. Gov't |
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Pagnoni F, Convelbo N, Tiendrebeogo J, Cousens S, Esposito F. A community-based programme to provide prompt and adequate treatment of presumptive malaria in children. Trans R Soc Trop Med Hyg 1997; 91:512-7. [PMID: 9463653 DOI: 10.1016/s0035-9203(97)90006-7] [Citation(s) in RCA: 93] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
A community-based programme to ensure prompt and adequate treatment of presumptive episodes of clinical malaria in children has been established in a rural province of Burkina Faso. The implementation strategy was based on training a core group of mothers in every village and supplying community health workers with essential antimalarial drugs specially packed in age-specific bags containing a full course of treatment. Drugs were sold under a cost-recovery scheme. The programme was run in 1994 by the national malaria control centre (CNLP), and in 1995 it was developed to the provincial health team (PHT). Knowledge and awareness of malaria increased with the intervention. Drug consumption by age group was compatible with the distribution of disease, and no major problem of misuse emerged. The actual implementation costs of the intervention were US$ 0.06 per child living in the province. An evaluation of the impact of the intervention on the severity of malaria, using routine data from the health information system and taking as an indicator the proportion of malaria cases which were recorded as severe in health centres, was performed. In 1994, when the intervention was implemented on a provincial scale by CNLP, this proportion was lower than the average of the 4 preceding years (3.7% vs. 4.9%). In 1995, when the programme was implemented by the PHT, the proportion of severe cases was lower in health centres achieving a programme coverage of > or = 50% in their catchment area compared with the others (4.2% vs. 6.1%). Our experience shows that a low-cost, community-based intervention aimed at providing children with prompt and adequate treatment of presumptive episodes of clinical malaria is feasible, and suggests that it may lead to a reduction in the morbidity from severe malaria.
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Sauerborn R, Nougtara A, Hien M, Diesfeld HJ. Seasonal variations of household costs of illness in Burkina Faso. Soc Sci Med 1996; 43:281-90. [PMID: 8844931 DOI: 10.1016/0277-9536(95)00374-6] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
This paper assesses the seasonal variations of the time and financial costs of illness for rural households in Burkina Faso. It is based on a multiple round survey of 566 households, which included a time allocation study. The economic parameters of households which influence health seeking behavior changed substantially between the dry and rainy seasons: revenues fell in the rainy season and were exceeded by expenditures. Household production was at its peak in the rainy season resulting in significantly higher opportunity costs of time. At the same time illness perception changed: in the rainy season, significantly fewer illness episodes were perceived, and of those, the proportion perceived as severe decreased over-proportionally. Households shifted their healer choice in the rainy season away from high cost treatment, such as the hospital and dispensary, to low cost home treatment. For all these reasons, households incurred significantly fewer costs of illness in the rainy season (27% of dry season costs). Household health care expenditures were reduced to 1/6 of dry season levels, the time costs incurred by healthy household members to tend to the sick was reduced to 1/5 and the time costs of work incapacity due to sickness fell to about 1/2 of dry season levels. The authors stress the need to carry out research in all relevant seasons when studying health seeking behavior and the household costs of illness in order to avoid serious seasonal bias. They suggest policy options to increase health care utilization in the rainy season by reducing the financial and time costs of access to health care. Finally, the authors put forward a hypothesis to be tested by future research: They argue that the cognitive (changes in illness perception) and behavioral changes (different health care seeking) reflect the high opportunity costs of time and the low availability of cash households face during the rainy season. The paper discusses the negative implication that untreated illness has on the health status of household members.
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Beiersmann C, Sanou A, Wladarsch E, De Allegri M, Kouyaté B, Müller O. Malaria in rural Burkina Faso: local illness concepts, patterns of traditional treatment and influence on health-seeking behaviour. Malar J 2007; 6:106. [PMID: 17686147 PMCID: PMC1971712 DOI: 10.1186/1475-2875-6-106] [Citation(s) in RCA: 91] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2007] [Accepted: 08/08/2007] [Indexed: 11/10/2022] Open
Abstract
UNLABELLED The literature on health care seeking behaviour in sub-Saharan Africa for children suffering from malaria is quite extensive. This literature, however, is predominantly quantitative and, inevitably, fails to explore how the local concepts of illness may affect people's choices. Understanding local concepts of illness and their influence on health care-seeking behaviour can complement existing knowledge and lead to the development of more effective malaria control interventions. METHODS In a rural area of Burkina Faso, four local concepts of illness resembling the biomedical picture of malaria were described according to symptoms, aetiology, and treatment. Data were collected through eight focus group discussions, 17 semi-structured interviews with key informants, and through the analysis of 100 verbal autopsy questionnaires of children under-five diagnosed with malaria. RESULTS Sumaya, dusukun yelema, kono, and djoliban were identified as the four main local illness concepts resembling respectively uncomplicated malaria, respiratory distress syndrome, cerebral malaria, and severe anaemia. The local disease categorization was found to affect both treatment and provider choice. While sumaya is usually treated by a mix of traditional and modern methods, dusukun yelema and kono are preferably treated by traditional healers, and djoliban is preferably treated in modern health facilities. Besides the conceptualization of illness, poverty was found to be another important influencing factor of health care-seeking behaviour. CONCLUSION The findings complement previous evidence on health care-seeking behaviour, by showing how local concepts of illness strongly influence treatment and choice of provider. Local concepts of illness need to be considered when developing specific malaria control programmes.
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Tiono AB, Ouédraogo A, Ouattara D, Bougouma EC, Coulibaly S, Diarra A, Faragher B, Guelbeogo MW, Grisales N, Ouédraogo IN, Ouédraogo ZA, Pinder M, Sanon S, Smith T, Vanobberghen F, Sagnon N, Ranson H, Lindsay SW. Efficacy of Olyset Duo, a bednet containing pyriproxyfen and permethrin, versus a permethrin-only net against clinical malaria in an area with highly pyrethroid-resistant vectors in rural Burkina Faso: a cluster-randomised controlled trial. Lancet 2018; 392:569-580. [PMID: 30104047 DOI: 10.1016/s0140-6736(18)31711-2] [Citation(s) in RCA: 84] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 07/16/2018] [Accepted: 07/19/2018] [Indexed: 11/17/2022]
Abstract
BACKGROUND Substantial reductions in malaria incidence in sub-Saharan Africa have been achieved with massive deployment of long-lasting insecticidal nets (LLINs), but pyrethroid resistance threatens control. Burkina Faso is an area with intense malaria transmission and highly pyrethroid-resistant vectors. We assessed the effectiveness of bednets containing permethrin, a pyrethroid, and pyriproxyfen, an insect growth regulator, versus permethrin-only (standard) LLINs against clinical malaria in children younger than 5 years in Banfora, Burkina Faso. METHODS In this two-group, step-wedge, cluster-randomised, controlled, superiority trial, standard LLINs were incrementally replaced with LLINs treated with permethrin plus pyriproxyfen (PPF) in 40 rural clusters in Burkina Faso. In each cluster, 50 children (aged 6 months to 5 years) were followed up by passive case detection for clinical malaria. Cross-sectional surveys were done at the start and the end of the transmission seasons in 2014 and 2015. We did monthly collections from indoor light traps to estimate vector densities. Primary endpoints were the incidence of clinical malaria, measured by passive case detection, and the entomological inoculation rate. Analyses were adjusted for clustering and for month and health centre. This trial is registered as ISRCTN21853394. FINDINGS 1980 children were enrolled in the cohort in 2014 and 2157 in 2015. At the end of the study, more than 99% of children slept under a bednet. The incidence of clinical malaria was 2·0 episodes per child-year in the standard LLIN group and 1·5 episodes per child-year in the PPF-treated LLIN group (incidence rate ratio 0·88 [95% CI 0·77-0·99; p=0·04]). The entomological inoculation rate was 85 (95% CI 63-108) infective bites per transmission season in the standard LLIN group versus 42 (32-52) infective bites per transmission season in the PPF-treated LLIN group (rate ratio 0·49, 95% CI 0·32-0·66; p<0·0001). INTERPRETATION PPF-treated LLINs provide greater protection against clinical malaria than do standard LLINs and could be used as an alternative to standard LLINs in areas with intense transmission of Plasmodium falciparum malaria and highly pyrethroid-resistant vectors. FUNDING EU Seventh Framework Programme.
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Comparative Study |
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Filippi V, Ganaba R, Baggaley RF, Marshall T, Storeng KT, Sombié I, Ouattara F, Ouedraogo T, Akoum M, Meda N. Health of women after severe obstetric complications in Burkina Faso: a longitudinal study. Lancet 2007; 370:1329-37. [PMID: 17933647 DOI: 10.1016/s0140-6736(07)61574-8] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
BACKGROUND Little is known about the health of women who survive obstetric complications in poor countries. Our aim was to determine how severe obstetric complications in Burkina Faso affect a range of health, social, and economic indicators in the first year post partum. METHODS We did a prospective cohort study of women with severe obstetric complications recruited in hospitals when their pregnancy ended with a livebirth (n=199), perinatal death (74), or a lost pregnancy (64). For every woman with severe obstetric complications, two unmatched control women with uncomplicated delivery were sampled in the same hospital (677). All women were followed up for 1 year. FINDINGS Women with severe obstetric complications were poorer and less educated at baseline than were women with uncomplicated delivery. Women with severe obstetric complications, and their babies, were significantly more likely to die after discharge: six (2%) of the 337 women with severe obstetric complications died within 1 year, compared with none of the women with uncomplicated delivery (unadjusted p=0.001); 17 babies of women with severe obstetric complications died within 1 year, compared with 18 of those born by uncomplicated delivery (hazard ratio for mortality 4.67, 95% CI 1.68-13.04, adjusted for loss to follow-up and confounders; p=0.003). Women with severe obstetric complications were significantly more likely to have experienced depression and anxiety at 3 months (odds ratio 1.82, 95% CI 1.18-2.80), to have experienced suicidal thoughts within the past year at all time points (2.27, 1.33-3.89 at 3 months; 2.30, 1.17-4.50 at 6 months; 2.26, 1.30-3.95 at 12 months), and to report the pregnancy having had a negative effect on their lives at all time points (1.54, 1.04-2.30 at 3 months; 2.30, 1.56-3.39 at 6 months; 2.44, 1.63-3.65 at 12 months) than were women with uncomplicated delivery. INTERPRETATION Women who give birth with severe obstetric complications are at greater risk of death and mental-health problems than are women with uncomplicated delivery. Greater resources are needed to ensure that these women receive adequate care before and after discharge from hospital.
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Multicenter Study |
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Abstract
Human onchocerciasis (river blindness) is the filarial infection caused by Onchocerca volvulus and transmitted among people through the bites of the Simulium vector. Some 86 million people around the world are at risk of acquiring the nematode, with 18 million people infected and 600,000 visually impaired, half of them partially or totally blind. 99% of cases occur in tropical Africa; scattered foci exist in Latin America. Until recently control programmes, in operation since 1975, have consisted of antivectorial measures. With the introduction of ivermectin in 1988, safe and effective chemotherapy is now available. With the original Onchocerciasis Control Programme of West Africa coming to an end, both the new African Programme for Onchocerciasis Control and the Onchocerciasis Elimination Programme for the Americas, rely heavily on ivermectin self-sustained mass delivery. In consequence, the need for understanding the processes regulating parasite abundance in human and simuliid populations is of utmost importance. We present a simple mathematical framework built around recent analyses of exposure- and density-dependent processes operating, respectively, within the human and vector hosts. An expression for the basic reproductive ratio, R0, is derived and related to the minimum vector density required for parasite persistence in localities of West Africa in general and northern Cameroon in particular. Model outputs suggest that constraints acting against parasite establishment in both humans and vectors are necessary to reproduce field observations, but those in humans may not fully protect against reinfection. Analyses of host age-profiles of infection prevalence, intensity, and aggregation for increasing levels of endemicity and intensity of transmission in the Vina valley of northern Cameroon are in agreement with these results and discussed in light of novel work on onchocerciasis immunology.
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Meissner PE, Mandi G, Coulibaly B, Witte S, Tapsoba T, Mansmann U, Rengelshausen J, Schiek W, Jahn A, Walter-Sack I, Mikus G, Burhenne J, Riedel KD, Schirmer RH, Kouyaté B, Müller O. Methylene blue for malaria in Africa: results from a dose-finding study in combination with chloroquine. Malar J 2006; 5:84. [PMID: 17026773 PMCID: PMC1617109 DOI: 10.1186/1475-2875-5-84] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2006] [Accepted: 10/08/2006] [Indexed: 11/10/2022] Open
Abstract
The development of safe, effective and affordable drug combinations against malaria in Africa is a public health priority. Methylene blue (MB) has a similar mode of action as chloroquine (CQ) and has moreover been shown to selectively inhibit the Plasmodium falciparum glutathione reductase. In 2004, an uncontrolled dose-finding study on the combination MB-CQ was performed in 435 young children with uncomplicated falciparum malaria in Burkina Faso (CQ monotherapy had a > 50% clinical failure rate in this area in 2003). Three serious adverse events (SAE) occurred of which one was probably attributable to the study medication. In the per protocol safety analysis, there were no dose specific effects. The overall clinical and parasitological failure rates by day 14 were 10% [95% CI (7.5%, 14.0%)] and 24% [95% CI (19.4%, 28.3%)], respectively. MB appears to have efficacy against malaria, but the combination of CQ-MB is clearly not effective in the treatment of malaria in Africa.
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Research Support, Non-U.S. Gov't |
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Vaugelade J, Pinchinat S, Guiella G, Elguero E, Simondon F. Non-specific effects of vaccination on child survival: prospective cohort study in Burkina Faso. BMJ 2004; 329:1309. [PMID: 15550402 PMCID: PMC534835 DOI: 10.1136/bmj.38261.496366.82] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/25/2004] [Indexed: 11/03/2022]
Abstract
OBJECTIVE To study the effect of vaccination on mortality before 2 years of age in a developing country. DESIGN Prospective cohort study. SETTING Rural communities in Burkina Faso. PARTICIPANTS 9085 children born in the study area between 1985 and 1993. MAIN OUTCOME MEASURE Child death rate. RESULTS Mortality before 2 years of age was lower in children who had been vaccinated: those vaccinated with BCG only had significantly lower mortality (risk ratio for vaccinated v unvaccinated children 0.37, 95% confidence interval 0.29 to 0.48) as did those vaccinated with diphtheria, tetanus, and pertussis only (0.24, 0.13 to 0.43). The second dose of diphtheria, tetanus, and pertussis was not associated with lower mortality (0.80, 0.58 to 1.12). CONCLUSION Vaccination with diphtheria, tetanus, and pertussis as well as BCG is associated with better survival of children up to 2 years of age.
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research-article |
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Sankoh OA, Yé Y, Sauerborn R, Müller O, Becher H. Clustering of childhood mortality in rural Burkina Faso. Int J Epidemiol 2001; 30:485-92. [PMID: 11416070 DOI: 10.1093/ije/30.3.485] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND Childhood mortality is a major public health problem in sub-Saharan Africa. For the implementation of efficient public health systems, knowledge of the spatial distribution of mortality is required. METHODS Data from a demographic surveillance research project were analysed which comprised information obtained for about 30 000 individuals from 39 villages in northwest Burkina Faso (West Africa) in the period 1993--1998. Total childhood mortality rates were calculated and the geographical distribution of total childhood mortality was investigated. In addition, data from a cohort of 686 children sampled from 16/39 of the villages followed up during a randomized controlled trial in 1999 were also used to validate the results from the surveillance data. A spatial scan statistic was used to test for clusters of total childhood mortality in both space and time. RESULTS Several statistically significant clusters of higher childhood mortality rates comprising different sets of villages were identified; one specific village was consistently identified in both study populations indicating non-random distribution of childhood mortality. Potential risk factors which were available in the database (ethnicity, religion, distance to nearest health centre) did not explain the spatial pattern. CONCLUSION The findings indicate non-random clustering of total childhood mortality in the study area. The study may be regarded as a first step in prioritizing areas for follow-up public health efforts.
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