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1.
PLoS Negl Trop Dis ; 14(12): e0008938, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33326420

RESUMEN

Soil-transmitted helminths (STH) are endemic and widespread across Sub-Saharan Africa. A community wide soil-transmitted helminth (STH) prevalence survey was performed on the island of Bubaque in Guinea-Bissau using both Kato-katz microscopy and qPCR methodology. Predictors of infection and morbidity indicators were identified using multivariable logistic regression, and diagnostic methods were compared using k statistics. Among 396 participants, prevalence of STH by microscopy was 23.2%, hookworm was the only species identified by this method and the mean infection intensity was 312 eggs per gram. qPCR analysis revealed an overall prevalence of any STH infection of 47.3%, with the majority A. duodenale (32.3%), followed by N. americanus (15.01%) and S. stercoralis (13.2%). A. lumbricoides, and T. trichiura infections were negligible, with a prevalence of 0.25% each. Agreement between diagnostic tests was k = 0.22, interpreted as fair agreement, and infection intensity measured by both methods was only minimally correlated (Rs = -0.03). STH infection overall was more common in females and adults aged 31-40. STH infection was associated with open defaecation, low socio-economic status and further distance to a water-source. The prevalence of anaemia (defined as a binary outcome by the WHO standards for age and sex) was 69.1%, and 44.2% of children were malnourished according to WHO child growth standards. Hookworm infection intensity by faecal egg count showed no statistically significant association with age (Rs 0.06) but S. Stercoralis infection intensity by qPCR cycle threshold was higher in pre-school aged children (Rs = 0.30, p-value 0.03) There was no statistically significant association between STH infection and anaemia (OR 1.0 p = 0.8), stunting (OR 1.9, p-value 0.5) and wasting (OR 2.0, p-value 0.2) in children. This study reveals a persistent reservoir of STH infection across the community, with high rates of anaemia and malnutrition, despite high-coverage of mebendazole mass-drug administration in pre-school children. This reflects the need for a new strategy to soil-transmitted helminth control, to reduce infections and ultimately eliminate transmission.


Asunto(s)
Antinematodos/uso terapéutico , Helmintiasis/epidemiología , Helmintos/aislamiento & purificación , Mebendazol/uso terapéutico , Suelo/parasitología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Niño , Preescolar , Estudios Transversales , Femenino , Guinea Bissau/epidemiología , Helmintiasis/parasitología , Helmintiasis/prevención & control , Humanos , Lactante , Masculino , Administración Masiva de Medicamentos , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Adulto Joven
2.
BMJ ; 370: m2397, 2020 07 22.
Artículo en Inglés | MEDLINE | ID: mdl-32699176

RESUMEN

OBJECTIVE: To assess the effects of food supplementation on improving working memory and additional measures including cerebral blood flow in children at risk of undernutrition. DESIGN: Randomized controlled trial. SETTING: 10 villages in Guinea-Bissau. PARTICIPANTS: 1059 children aged 15 months to 7 years; children younger than 4 were the primary population. INTERVENTIONS: Supervised isocaloric servings (≈1300 kJ, five mornings each week, 23 weeks) of a new food supplement (NEWSUP, high in plant polyphenols and omega 3 fatty acids, within a wide variety and high fortification of micronutrients, and a high protein content), or a fortified blended food (FBF) used in nutrition programs, or a control meal (traditional rice breakfast). MAIN OUTCOME MEASUREMENTS: The primary outcome was working memory, a core executive function predicting long term academic achievement. Additional outcomes were hemoglobin concentration, growth, body composition, and index of cerebral blood flow (CBFi). In addition to an intention-to-treat analysis, a predefined per protocol analysis was conducted in children who consumed at least 75% of the supplement (820/925, 89%). The primary outcome was assessed by a multivariable Poisson model; other outcomes were assessed by multivariable linear mixed models. RESULTS: Among children younger than 4, randomization to NEWSUP increased working memory compared with the control meal (rate ratio 1.20, 95% confidence interval 1.02 to 1.41, P=0.03), with a larger effect in the per protocol population (1.25, 1.06 to 1.47, P=0.009). NEWSUP also increased hemoglobin concentration among children with anemia (adjusted mean difference 0.65 g/dL, 95% confidence interval 0.23 to 1.07, P=0.003) compared with the control meal, decreased body mass index z score gain (-0.23, -0.43 to -0.02, P=0.03), and increased lean tissue accretion (2.98 cm2, 0.04 to 5.92, P=0.046) with less fat (-5.82 cm2, -11.28 to -0.36, P=0.04) compared with FBF. Additionally, NEWSUP increased CBFi compared with the control meal and FBF in both age groups combined (1.14 mm2/s×10-8, 0.10 to 2.23, P=0.04 for both comparisons). Among children aged 4 and older, NEWSUP had no significant effect on working memory or anemia, but increased lean tissue compared with FBF (4.31 cm2, 0.34 to 8.28, P=0.03). CONCLUSIONS: Childhood undernutrition is associated with long term impairment in cognition. Contrary to current understanding, supplementary feeding for 23 weeks could improve executive function, brain health, and nutritional status in vulnerable young children living in low income countries. Further research is needed to optimize nutritional prescriptions for regenerative improvements in cognitive function, and to test effectiveness in other vulnerable groups. TRIAL REGISTRATION: ClinicalTrials.gov NCT03017209.


Asunto(s)
Anemia/dietoterapia , Disfunción Cognitiva/dietoterapia , Suplementos Dietéticos/efectos adversos , Desnutrición/dietoterapia , Estado Nutricional/fisiología , Éxito Académico , Anemia/epidemiología , Estudios de Casos y Controles , Circulación Cerebrovascular/fisiología , Niño , Preescolar , Cognición/fisiología , Disfunción Cognitiva/fisiopatología , Suplementos Dietéticos/estadística & datos numéricos , Femenino , Alimentos Fortificados/provisión & distribución , Guinea Bissau/epidemiología , Humanos , Lactante , Análisis de Intención de Tratar/métodos , Masculino , Desnutrición/epidemiología , Desnutrición/prevención & control , Micronutrientes/provisión & distribución , Medición de Riesgo
3.
J Pediatric Infect Dis Soc ; 9(2): 166-172, 2020 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-30715451

RESUMEN

BACKGROUND AND HYPOTHESIS: Maternal priming might enhance the beneficial nonspecific effects (NSEs) of live measles vaccination (MV). Children with a bacillus Calmette-Guérin (BCG) vaccine scar have a lower mortality rate than those without a scar that is not explained by protection against tuberculosis. We examined the hypothesis that BCG scarring would have a stronger effect on a child if the mother also had a BCG scar. METHODS: In a randomized controlled trial (RCT) of early MV in children aged 4.5 months, the BCG-scar status of the children and their mother were registered at enrollment at 4.5 months of age. The children were followed up until they were 36 months of age. Using a Cox proportional hazards model, we compared mortality rate ratios according to maternal and child BCG-scar status after adjusting for where the BCG vaccine was given (the national hospital or elsewhere). We censored for other interventions that have immunomodulating effects on child survival, including neonatal vitamin A supplementation and early MV. RESULTS: A total of 2213 children had not received neonatal vitamin A supplementation and early MV; 83% of these children and 44% of the mothers had a BCG scar. Children whose mother had a BCG scar were not more likely to have a BCG scar than those whose mother did not have a BCG scar (risk ratio, 1.01 [95% confidence interval (CI), 0.98-1.05]). Among the children, having a BCG scar was associated with a 41% (95% CI, 5%-64%) lower mortality between the ages of 4.5 and 36 months. The reduction in mortality was 66% (95% CI, 33%-83%) if the mother also had a BCG scar but only 8% (95% CI, -83% to 53%) if the mother had no BCG scar (test of interaction, P = .04). CONCLUSIONS: Maternal BCG priming might be important for the effect of BCG vaccination on child survival. Ensuring better BCG vaccine scarring among mothers and children could have a considerable effect on child mortality levels.


Asunto(s)
Vacuna BCG , Mortalidad del Niño , Cicatriz , Vacunación , Preescolar , Femenino , Estudios de Seguimiento , Guinea Bissau/epidemiología , Humanos , Lactante , Masculino , Madres , Modelos de Riesgos Proporcionales , Tuberculosis/prevención & control , Vacunación/estadística & datos numéricos
4.
J Pediatric Infect Dis Soc ; 7(3): 226-233, 2018 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-28992261

RESUMEN

BACKGROUND: Two doses of measles vaccine (MV) might reduce the nonmeasles mortality rate more than 1 dose of MV does. The effect of 2 versus 1 dose on morbidity has not been examined. Within a randomized trial of the effect of 2 doses versus 1 dose of MV on mortality in Guinea-Bissau, we investigated the effect on hospital admissions. METHODS: Children were randomly assigned 1:2 to receive MV at 4.5 and 9 months of age or the currently recommended dose at 9 months. We compared hospital admission rates among children between 9 and 18 months of age in a Cox regression model with age as the underlying time scale. Half of the children had received neonatal vitamin A supplementation (NVAS) in another trial. The beneficial effect of MV at 4.5 and 9 months on mortality was limited to children who had not received NVAS; therefore, we investigated the interaction of MV with NVAS on admission rates. RESULTS: Among 5626 children (2 doses of MV, 1960 children; 1 dose of MV, 3666), we identified 311 hospital admissions of children between 9 and 18 months of age. Overall, compared to 1 dose of MV, 2 doses reduced the risk of hospital admission for children who had not received NVAS (hazard ratio [HR], 0.66 [95% confidence interval (CI), 0.47-0.93]), but we found no effect among NVAS recipients (HR, 1.16 [95% CI, 0.82-1.63]) (P = .02 for interaction). CONCLUSIONS: The benefit of 2 doses of MV was limited to children who had not received NVAS. NVAS is not generally recommended; hence, an early 2-dose measles vaccination policy might reduce hospital admissions more than the current policy of providing the first MV at 9 months of age. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT00168558.


Asunto(s)
Hospitalización/estadística & datos numéricos , Vacuna Antisarampión/administración & dosificación , Sarampión/prevención & control , Suplementos Dietéticos , Esquema de Medicación , Femenino , Guinea Bissau/epidemiología , Humanos , Esquemas de Inmunización , Lactante , Masculino , Sarampión/mortalidad , Modelos de Riesgos Proporcionales , Vitamina A/administración & dosificación , Vitaminas/administración & dosificación
5.
Br J Nutr ; 115(4): 619-28, 2016 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-26678511

RESUMEN

As WHO recommends vitamin A supplementation (VAS) at vaccination contacts after age 6 months, many children receive VAS together with measles vaccine (MV). We aimed to investigate the immunological effect of VAS given with MV. Within a randomised placebo-controlled trial investigating the effect on overall mortality of providing VAS with vaccines in Guinea-Bissau, we conducted an immunological sub-study of VAS v. placebo with MV, analysing leucocyte counts, whole blood in vitro cytokine production, vitamin A status and concentration of C-reactive protein (CRP). VAS compared with placebo was associated with an increased frequency of CRP ≥ 5 mg/l (28 v. 12%; P=0·005). Six weeks after supplementation, VAS had significant sex-differential effects on leucocyte, lymphocyte, monocyte and basophil cell counts, decreasing them in males but increasing them in females. Mainly in females, the effect of VAS on cytokine responses differed by previous VAS: in previous VAS recipients, VAS increased the pro-inflammatory and T helper cell type 1 (Th1) cytokine responses, whereas VAS decreased these responses in previously unsupplemented children. In previous VAS recipients, VAS was associated with increased IFN-γ responses to phytohaemagglutinin in females (geometric mean ratio (GMR): 3·97; 95% CI 1·44, 10·90) but not in males (GMR 0·44; 95% CI 0·14, 1·42); the opposite was observed in previously unsupplemented children. Our results corroborate that VAS provided with MV has immunological effects, which may depend on sex and previous VAS. VAS may increase the number of leucocytes, but also repress both the innate and lymphocyte-derived cytokine responses in females, whereas this repression may be opposite if the females have previously received VAS.


Asunto(s)
Suplementos Dietéticos , Inmunidad Heteróloga , Leucocitos/inmunología , Vacuna Antisarampión/uso terapéutico , Sarampión/prevención & control , Deficiencia de Vitamina A/prevención & control , Vitamina A/uso terapéutico , Biomarcadores/sangre , Biomarcadores/metabolismo , Células Sanguíneas/citología , Células Sanguíneas/inmunología , Células Sanguíneas/metabolismo , Células Sanguíneas/patología , Células Cultivadas , Citocinas/sangre , Citocinas/metabolismo , Suplementos Dietéticos/efectos adversos , Femenino , Estudios de Seguimiento , Guinea Bissau/epidemiología , Humanos , Lactante , Recuento de Leucocitos , Leucocitos/citología , Leucocitos/metabolismo , Leucocitos/patología , Perdida de Seguimiento , Masculino , Sarampión/inmunología , Sarampión/metabolismo , Sarampión/patología , Vacuna Antisarampión/efectos adversos , Estado Nutricional , Prevalencia , Caracteres Sexuales , Vitamina A/efectos adversos , Deficiencia de Vitamina A/epidemiología , Deficiencia de Vitamina A/inmunología , Deficiencia de Vitamina A/metabolismo
6.
Br J Nutr ; 114(7): 1072-9, 2015 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-26285696

RESUMEN

While prenatal Fe supplementation prevents maternal Fe deficiency and anaemia, it is uncertain whether it improves infant health outcomes, at least when taken by Fe-replete women. Inflammation as well as physiological changes complicates the assessment of Fe status during pregnancy. In the present study, we measured the concentrations of serum ferritin and soluble transferrin receptors (sTfR), Hb and the acute-phase proteins C-reactive protein (CRP) and α1-antichymotrypsin (ACT) in a cross-sectional study among 738 pregnant women attending antenatal care in Guinea-Bissau, West Africa. Multiple linear regression analysis was used to identify the predictors of Fe status markers. The mean gestational age was 23 (sd 7) weeks. Serum ferritin values were lower with progressing gestation, from 27% lower during weeks 16-20 of gestation up to 59% lower after 29 weeks of gestation compared with early pregnancy. Using cut-off values for Fe deficiency as established in non-pregnant individuals, 52% of the women had sTfR levels >2·3 mg/l, while only 25% had serum ferritin levels 2·3 mg/l decreased to 47% after adjustment for elevated serum CRP and ACT levels. On the contrary, the proportion of serum ferritin < 12 µg/l increased to 33% after adjustment for ACT and CRP. The high proportion of elevated serum sTfR calls for pregnancy-specific cut-offs since increased erythropoiesis is expected in response to increased plasma volume of pregnancy. The present study further underlines the need to adjust for inflammation when serum sTfR and serum ferritin are used to assess Fe status in pregnancy.


Asunto(s)
Reacción de Fase Aguda/sangre , Reacción de Fase Aguda/epidemiología , Anemia Ferropénica/epidemiología , Biomarcadores/sangre , Hierro/sangre , Complicaciones Hematológicas del Embarazo/epidemiología , Adolescente , Adulto , Anemia Ferropénica/sangre , Proteína C-Reactiva/metabolismo , Estudios Transversales , Suplementos Dietéticos , Femenino , Ferritinas/sangre , Guinea Bissau/epidemiología , Humanos , Hierro de la Dieta/administración & dosificación , Modelos Lineales , Embarazo , Complicaciones Hematológicas del Embarazo/sangre , Receptores de Transferrina/sangre , Adulto Joven , alfa 1-Antiquimotripsina/sangre
7.
Pediatrics ; 134(3): e739-48, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25136048

RESUMEN

BACKGROUND: The World Health Organization recommends vitamin A supplementation (VAS) at routine vaccination contacts after 6 months of age based on the assumption that it reduces mortality by 24%. The policy has never been evaluated in randomized controlled trials for its effect on overall mortality. We conducted a randomized double-blind trial to evaluate the effect of VAS with vaccines. METHODS: We randomized children aged 6 to 23 months 1:1 to VAS (100000 IU if aged 6-11 months, 200000 IU if aged 12-23 months) or placebo at vaccination contacts in Guinea-Bissau. Mortality rates were compared in Cox proportional-hazards models overall, and by gender and vaccine. RESULTS: Between August 2007 and November 2010, 7587 children were enrolled. Within 6 months of follow-up 80 nonaccident deaths occurred (VAS: 38; placebo: 42). The mortality rate ratio (MRR) comparing VAS versus placebo recipients was 0.91 (95% confidence interval 0.59-1.41) and differed significantly between boys (MRR 1.92 [0.98-3.75]) and girls (MRR 0.45 [0.24-0.87]) (P = .003 for interaction between VAS and gender). At enrollment, 42% (3161/7587) received live measles vaccine, 29% (2154/7587) received inactivated diphtheria-tetanus-pertussis-containing vaccines, and 21% (1610/7587) received both live and inactivated vaccines. The effect of VAS did not differ by vaccine group. CONCLUSIONS: This is the first randomized controlled trial to assess the effect of the policy on overall mortality. VAS had no overall effect, but the effect differed significantly by gender. More trials to ensure an optimal evidence-based vitamin A policy are warranted.


Asunto(s)
Vacuna contra Difteria, Tétanos y Tos Ferina/administración & dosificación , Vacuna Antisarampión/administración & dosificación , Vacunación/mortalidad , Vacunación/métodos , Vitamina A/administración & dosificación , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Guinea Bissau/epidemiología , Humanos , Lactante , Masculino , Mortalidad/tendencias
8.
BMC Pediatr ; 14: 214, 2014 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-25163399

RESUMEN

BACKGROUND: The effect of oral polio vaccine administered already at birth (OPV0) on child survival was not examined before being recommended in 1985. Observational data suggested that OPV0 was harmful for boys, and trials have shown that neonatal vitamin A supplementation (NVAS) at birth may be beneficial for boys. We set out to test this research question in a randomised trial. METHODS: The trial was carried out at the Bandim Health Project, Guinea-Bissau. We planned to enrol 900 low-birth weight (LBW) boys in a randomised trial to investigate whether NVAS instead of OPV0 could lower infant mortality for LBW boys. At birth, the children were randomised to OPV (usual treatment) or VAS (intervention treatment) and followed for 6 months for growth and 12 months for survival. Hazard Ratios (HR) for mortality were calculated using Cox regression. We compared the individual anthropometry measurements to the 2006 WHO growth reference. We compared differences in z-scores by linear regression. Relative risks (RR) of being stunted or underweight were calculated in Poisson regression models with robust standard errors. RESULTS: In the rainy season we detected a cluster of deaths in the VAS group and the trial was halted immediately with 232 boys enrolled. The VAS group had significantly higher mortality than the OPV0 group in the rainy season (HR: 9.91 (1.23 - 80)). All deaths had had contact with the neonatal nursery; of seven VAS boys enrolled during one week in September, six died within two months of age, whereas only one died among the six boys receiving OPV (p = 0.05). Growth (weight and arm-circumference) in the VAS group was significantly worse until age 3 months. CONCLUSION: VAS at birth instead of OPV was not beneficial for the LBW boys in this study. With the premature closure of the trial it was not possible to answer the research question. However, the results of this study call for extra caution when testing the effect of NVAS in the future. TRIAL REGISTRATION: http://www.clinicaltrials.gov NCT00625482. Registered 18 February 2008.


Asunto(s)
Desarrollo Infantil/efectos de los fármacos , Suplementos Dietéticos/efectos adversos , Mortalidad Infantil , Recién Nacido de Bajo Peso/crecimiento & desarrollo , Vacuna Antipolio Oral , Vitamina A/efectos adversos , Vitaminas/efectos adversos , Administración Oral , Causas de Muerte , Países en Desarrollo , Terminación Anticipada de los Ensayos Clínicos , Estudios de Seguimiento , Guinea Bissau/epidemiología , Humanos , Lactante , Recién Nacido , Masculino , Vacuna Antipolio Oral/administración & dosificación , Modelos de Riesgos Proporcionales , Lluvia , Estaciones del Año , Vitamina A/administración & dosificación , Vitaminas/administración & dosificación
9.
J Infect Dis ; 209(11): 1731-8, 2014 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-24436454

RESUMEN

Observational studies and trials from low-income countries indicate that measles vaccine has beneficial nonspecific effects, protecting against non-measles-related mortality. It is not known whether measles vaccine protects against hospital admissions. Between 2003 and 2007, 6417 children who had received the third dose of diphtheria, tetanus, and pertussis vaccine were randomly assigned to receive measles vaccine at 4.5 months or no measles vaccine; all children were offered measles vaccine at 9 months of age. Using hospital admission data from the national pediatric ward in Bissau, Guinea-Bissau, we compared admission rates between enrollment and the 9-month vaccination in Cox models, providing admission hazard rate ratios (HRRs) for measles vaccine versus no measles vaccine. All analyses were conducted stratified by sex and reception of neonatal vitamin A supplementation (NVAS). Before enrollment the 2 groups had similar admission rates. Following enrollment, the measles vaccine group had an admission HRR of 0.70 (95% confidence interval [CI], .52-.95), with a ratio of 0.53 (95% CI, .32-.86) for girls and 0.86 (95% CI, .58-1.26) for boys. For children who had not received NVAS, the admission HRR was 0.53 (95% CI, .34-.84), with an effect of 0.30 (95% CI, .13-.70) for girls and 0.73 (95% CI, .42-1.28) for boys (P = .08, interaction test). The reduction in admissions was separately significant for measles infection (admission HRR, 0 [95% CI, 0-.24]) and respiratory infections (admission HRR, 0.37 [95% CI, .16-.89]). Early measles vaccine may have major benefits for infant morbidity patterns and healthcare costs. Clinical trials registration NCT00168558.


Asunto(s)
Vacuna Antisarampión/inmunología , Sarampión/prevención & control , Suplementos Dietéticos , Femenino , Guinea Bissau/epidemiología , Hospitalización , Humanos , Esquemas de Inmunización , Lactante , Masculino , Sarampión/epidemiología , Vacuna Antisarampión/administración & dosificación , Factores de Riesgo , Factores Sexuales , Vitamina A/administración & dosificación , Vitamina A/farmacología
10.
BMC Pediatr ; 13: 190, 2013 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-24252418

RESUMEN

BACKGROUND: The World Health Organization recommends high-dose vitamin A supplementation (VAS) for children above six months of age in low-income countries. VAS has been associated with up-regulation of the Th2 response. We aimed to determine if VAS is associated with atopy in childhood. METHODS: Infants in Guinea-Bissau were randomly allocated VAS or placebo, either at six and nine months of age, or only at nine months of age. At six months of age, children were furthermore randomized to measles vaccine or inactivated polio vaccine. At nine months of age all children received measles vaccine. Children were revisited seven years later and skin prick testing was performed. Atopy was defined as a skin prick reaction ≥ 3 mm. RESULTS: 40 of 263 children (15%) were atopic. Overall VAS had no significant effect on the risk of atopy (Prevalence Ratio 1.23; 95% CI 0.69-2.18). The Prevalence Ratio was 1.60 (0.66-3.90) for males and 1.00 (0.46-2.15) for females. CONCLUSIONS: There was no significant effect of VAS in infancy on atopy later in childhood. The role of infant VAS in the development of atopy is still unclear.


Asunto(s)
Suplementos Dietéticos/efectos adversos , Hipersensibilidad Inmediata/etiología , Vitamina A/efectos adversos , Antropometría , Femenino , Estudios de Seguimiento , Guinea Bissau/epidemiología , Humanos , Hipersensibilidad Inmediata/epidemiología , Hipersensibilidad Inmediata/inmunología , Lactante , Pruebas Intradérmicas , Masculino , Vacuna Antisarampión , Vacuna Antipolio de Virus Inactivados , Células Th2/efectos de los fármacos , Vitamina A/farmacología
11.
Paediatr Int Child Health ; 33(3): 151-60, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23930727

RESUMEN

BACKGROUND: Childhood malnutrition is the leading risk factor for the global burden of disease. Guinea-Bissau is a politically unstable country with high levels of childhood malnutrition and mortality. AIM: To determine the nutritional status of children on three remote islands of the Bijagós Archipelago, Bubaque, Rubane and Soga, and to identify factors associated with malnutrition and anaemia in this population in order to provide a baseline for future public health interventions. METHODS: A cross-sectional, population-based, door-to-door household survey of randomly selected households was undertaken to collect data on children aged 0-59 months (n = 872). Dietary information was collected using a validated questionnaire. Anthropometric measurements were collected using World Health Organization techniques. Capillary blood samples were analysed using a Hemocue®, with anaemia defined as Hb<11 g/dl. RESULTS: The prevalences of stunted, wasted and underweight children were 21.8%, 9.4% and 3.7%, respectively. These figures indicate moderate chronic malnutrition. The significant predictor variables for stunting were: age in months (OR 1.03), rural residence (OR 2.32), anaemia (OR 3.55) and residence on Soga island (OR 0.44). Stunting was more prevalent in males (25.4%) than in females (18.6%) (P = 0.03). The prevalence of anaemia was 80.2%. Age (OR 0.96), male gender (OR 1.81) and stunting (OR 2.87) were significant predictors. The Minimum Acceptable Diet was achieved by only 8.7% of children. CONCLUSION: The prevalence of malnutrition on the Bijagós Archipelago is less than half that on the mainland. This study is the first to determine the prevalence of anaemia in Guinea-Bissau, which, at 80.2%, is of severe public health concern. Future research should focus on the aetiology of stunting and anaemia, especially the contribution of infectious diseases and mother-child interaction. Iron supplementation should be strongly considered in this population.


Asunto(s)
Anemia/epidemiología , Anemia/etiología , Trastornos de la Nutrición del Niño/complicaciones , Trastornos de la Nutrición del Niño/epidemiología , Antropometría , Preescolar , Estudios Transversales , Femenino , Guinea Bissau/epidemiología , Humanos , Lactante , Recién Nacido , Masculino , Prevalencia , Distribución Aleatoria , Encuestas y Cuestionarios
12.
BMC Pediatr ; 13: 87, 2013 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-23702185

RESUMEN

BACKGROUND: Vitamin A supplementation (VAS) may amplify the effect of vaccines. We therefore investigated if neonatal VAS given with and without Bacille Calmette-Guérin (BCG) vaccine to low-birth-weight (LBW) neonates had an effect on growth in the first year of life. We hypothesised that VAS would be particularly beneficial when provided with BCG. METHODS: We conducted a randomised two-by-two factorial trial in Guinea-Bissau; 1,717 LBW neonates were randomly allocated to VAS or placebo at birth as well as early or the usual postponed BCG vaccination. Anthropometric measurements were obtained at 2, 6, and 12 months after inclusion. RESULTS: Overall there was no effect of neonatal VAS on growth in the first year of life. By 2 months, VAS tended to have a beneficial effect on weight and head circumference when given with BCG but not when given without BCG (interaction: weight-for-age p = 0.07 and head circumference-for-age: p = 0.06). By 6 months, there was a beneficial effect of VAS on head circumference and weight among children who had not received DTP vaccine 2 months after inclusion (weight: 0.18 (0.00; 0.36) and head circumference 0.27 (0.06; 0.48)), but no beneficial effect among those who had received DTP. CONCLUSION: The results support other trials indicating that neonatal VAS does not have consistent effects on childhood growth and if anything the effects seem to be temporary. They also show that the effect may differ by vaccination status, being beneficial when given with BCG at birth and when DTP is delayed. TRIAL REGISTRATION: www.ClinicalTrials.gov (NCT00168610).


Asunto(s)
Suplementos Dietéticos , Recién Nacido de Bajo Peso , Deficiencia de Vitamina A/prevención & control , Vitamina A/administración & dosificación , Adyuvantes Inmunológicos/administración & dosificación , Vacuna BCG/administración & dosificación , Peso Corporal , Femenino , Estudios de Seguimiento , Guinea Bissau/epidemiología , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Estudios Retrospectivos , Vacunación , Deficiencia de Vitamina A/epidemiología , Vitaminas/administración & dosificación
13.
BMC Public Health ; 13: 172, 2013 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-23442248

RESUMEN

BACKGROUND: The World Health Organization (WHO) classifies Guinea-Bissau as having severe vitamin A deficiency (VAD). To date, no national survey has been conducted. We assessed vitamin A status among children in rural Guinea-Bissau to assess status and identify risk factors for VAD. METHODS: In a vitamin A supplementation trial in rural Guinea-Bissau, children aged 6 months to 2 years who were missing one or more vaccines were enrolled, vaccinated and randomized to vitamin A or placebo. Provided consent, a dried blood spot (DBS) sample was obtained from a subgroup of participants prior to supplementation. Vitamin A status and current infection was assessed by an ELISA measuring retinol-binding protein (RBP) and C-reactive protein (CRP). VAD was defined as RBP concentrations equivalent to plasma retinol <0.7 µmol/L; infection was defined as CRP >5 ml/L. In Poisson regression models providing prevalence ratios (PR), we investigated putative risk factors for VAD including sex, age, child factors, maternal factors, season (rainy: June-November; dry: December-May), geography, and use of health services. RESULTS: Based on DBS from 1102 children, the VAD prevalence was 65.7% (95% confidence interval 62.9-68.5), 11% higher than the WHO estimate of 54.7% (9.9-93.0). If children with infection were excluded, the prevalence was 60.2% (56.7-63.7). In the age group 9-11 months, there was no difference in prevalence of VAD among children who had received previous vaccines in a timely fashion and those who had not. Controlled for infection and other determinants of VAD, the prevalence of VAD was 1.64 (1.49-1.81) times higher in the rainy season compared to the dry, and varied up to 2-fold between ethnic groups and regions. Compared with having an inactivated vaccine as the most recent vaccine, having a live vaccine as the most recent vaccination was associated with lower prevalence of VAD (PR=0.84 (0.74-0.96)). CONCLUSIONS: The prevalence of VAD was high in rural Guinea-Bissau. VAD varied significantly with season, ethnicity, region, and vaccination status. TRIAL REGISTRATION: Clinicaltrials.gov NCT00514891.


Asunto(s)
Salud Rural/estadística & datos numéricos , Deficiencia de Vitamina A/epidemiología , Preescolar , Etnicidad/estadística & datos numéricos , Femenino , Guinea Bissau/epidemiología , Humanos , Lactante , Masculino , Factores de Riesgo , Estaciones del Año , Vacunación/estadística & datos numéricos , Deficiencia de Vitamina A/etnología
14.
Vaccine ; 30(47): 6694-9, 2012 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-22959984

RESUMEN

BACKGROUND: WHO recommends oral polio vaccine at birth (OPV0) in polio endemic countries. During a period without OPV in Guinea-Bissau in 2004, we observed that not receiving OPV0 was associated with significantly decreased mortality in boys and better immune response to BCG vaccination. In 2007, whilst conducting a trial of BCG and vitamin A supplementation (VAS) at birth to low birthweight (LBW) children, OPV was again lacking for a short period. We used this natural experiment to test the previous observations. METHODS: In the trial LBW infants were randomised to early or delayed BCG and VAS or placebo at birth. We noted whether the children received OPV0 or not. We compared children who received No OPV0 with those who received OPV0 in the 2 months before and the 2 months after the period without OPV. Mortality was compared in Cox regression models providing adjusted hazard ratios (aHR); the immune response to BCG was assessed in Poisson models providing adjusted prevalence ratios (aPR). RESULTS: Ninety-nine children received No OPV0 and were compared with 243 children who received OPV0. No OPV0 was associated with insignificantly higher mortality during the first year of life, the aHR being 1.83 (95% CI: 0.93-3.61). The effect was similar in boys and girls. Overall, there was no significant association between No OPV0 and having a positive PPD response (aPR=1.33 (0.64-2.78)) or a scar (aPR=1.02 (0.93-1.11)) after BCG vaccination, though No OPV0 boys were more likely to develop a scar (aPR: 1.10 (1.01-1.20)). CONCLUSIONS: The findings did not support our previous observation that not receiving OPV0 was associated with reduced mortality in boys. The findings weakly supported that OPV0 leads to a dampened response to simultaneously administered BCG vaccine in boys.


Asunto(s)
Vacuna BCG/uso terapéutico , Vacuna Antipolio Oral/efectos adversos , Vacuna Antipolio Oral/uso terapéutico , Vacunación/mortalidad , Vacuna BCG/inmunología , Femenino , Guinea Bissau/epidemiología , Humanos , Lactante , Mortalidad Infantil , Recién Nacido , Masculino , Distribución de Poisson , Modelos de Riesgos Proporcionales , Factores Sexuales , Vitamina A/uso terapéutico
15.
AIDS Res Hum Retroviruses ; 28(11): 1434-43, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22747336

RESUMEN

The high HIV-1 prevalence, up to 4.6% in Guinea-Bissau, West Africa, makes it a relevant location for testing of therapeutic vaccines. With the aim of performing a clinical study in Guinea-Bissau, after first testing the vaccine for safety in Denmark, Europe, we here describe the design of a universal epitope peptide-based T cell vaccine with relevance for any geographic locations. The two major obstacles when designing such a vaccine are the high diversities of the HIV-1 genome and of the human major histocompatibility complex (MHC) class I. We selected 15 CD8-restricted epitopes predicted from conserved regions of HIV-1 that were subdominant (i.e., infrequently targeted) within natural infections. Moreover, the epitopes were predicted to be restricted to at least one of the five common HLA supertypes (HLA-A01, A02, A03, B07, and B44). Here, we validated the resulting peptide-specific, HLA-restricted T cell specificities using peptide-MHC class I tetramer labeling of CD8(+) T cells from HIV-1-infected individuals. The selected vaccine epitopes are infrequently targeted in HIV-1-infected individuals from both locations. Moreover, we HLA-typed HIV-1-infected individuals and demonstrated that the selected vaccine epitopes, when targeted, are restricted to the five most common HLA supertypes at both locations. Thus, the HLA supertype-directed approach achieved HLA coverage of 95% and 100% of the examined cohorts in Guinea-Bissau and Denmark, respectively. In conclusion, the selected vaccine epitopes match the host populations and HIV-1 strains of these two distant geographic regions, justifying clinical testing in both locations.


Asunto(s)
Vacunas contra el SIDA , Linfocitos T CD8-positivos/inmunología , Epítopos de Linfocito T/inmunología , Infecciones por VIH/prevención & control , VIH-1/inmunología , Antígenos HLA/inmunología , Vacunas de ADN , Vacunas contra el SIDA/inmunología , Adolescente , Adulto , Dinamarca/epidemiología , Evaluación Preclínica de Medicamentos , Femenino , Guinea Bissau/epidemiología , Infecciones por VIH/epidemiología , Infecciones por VIH/inmunología , Prueba de Histocompatibilidad , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Valor Predictivo de las Pruebas , Alineación de Secuencia , Vacunas de ADN/inmunología
16.
BMC Pediatr ; 11: 77, 2011 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-21884606

RESUMEN

BACKGROUND: Vitamin A supplementation (VAS) given to children between 6 months and 5 years of age is known to reduce mortality in low-income countries. We have previously observed that girls benefit more from a lower dose of VAS than the one recommended by WHO, the effect being strongest if diphtheria-tetanus-pertussis vaccine (DTP) was the most recent vaccination. We aimed to test these observations. METHODS: During national immunisations days in Guinea-Bissau, West Africa, combining oral polio vaccination and VAS, we randomised 8626 children between 6 months and 5 years of age to receive the dose of VAS recommended by WHO or half this dose. Mortality rate ratios (MRRs) were assessed after 6 and 12 month. RESULTS: The overall mortality rate among participants was lower than expected. There was no significant difference in mortality at 6 months and 12 months of follow up between the low dose VAS group and the recommended dose VAS group. The MRRs were 1.23 (0.60-2.54) after 6 months and 1.17 (0.73-1.87) after 12 months. This tendency was similar in boys and girls. The low dose was not associated with lower mortality in girls if the most recent vaccine was DTP (MRR = 0.60 (0.14-2.50) after 6 months). CONCLUSION: Our sample size does not permit firm conclusions since mortality was lower than expected. We could not confirm a beneficial effect of a lower dose of VAS on mortality in girls. TRIAL REGISTRATION: The study was registered under clinicaltrials.gov, number NCT00168636.


Asunto(s)
Mortalidad , Vitamina A/administración & dosificación , Vitaminas/administración & dosificación , Preescolar , Países en Desarrollo , Relación Dosis-Respuesta a Droga , Femenino , Estudios de Seguimiento , Guinea Bissau/epidemiología , Humanos , Lactante , Masculino , Vigilancia de la Población , Distribución por Sexo , Vacunación
17.
PLoS One ; 6(8): e23265, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21853099

RESUMEN

OBJECTIVES: Within a randomised trial of neonatal vitamin A supplementation (VAS) in Guinea-Bissau, neonatal VAS did not affect overall infant mortality. We conducted a post-hoc analysis to test the hypothesis that neonatal VAS primes the response to subsequent vitamin A. METHODS: All trial children were offered VAS after follow-up ended at 1 year of age (FU-VAS). We compared mortality between 1 and 3 years of age according to initial randomization to neonatal VAS or placebo in Cox-regression models; we expected that children randomized to neonatal VAS compared with those randomized to placebo would have lower mortality after reception of FU-VAS. RESULTS: Of 4345 infants enrolled in the original trial, 3646 lived in the study area at 1 year of age and 2958 received FU-VAS. Between 1 and 3 years of age, 112 children died. After FU-VAS, neonatal VAS was associated with lower mortality than placebo: Mortality Rate Ratio (MRR) = 0.54 (95%CI: 0.31-0.94). The effect was more pronounced in girls (MRR = 0.37 (0.16-0.89)) than boys (MRR = 0.73 (0.35-1.51)). The beneficial effect of neonatal VAS may have been particularly strong for girls who received both VAS in a campaign and FU-VAS (MRR = 0.15 (0.03-0.67)). Among children who had not received FU-VAS, mortality in the second and third year of life did not differ according to reception of neonatal VAS or placebo. Hence, in the second and third year of life the effect of neonatal VAS versus placebo was different in girls who had or had not received FU-VAS (p for homogeneity = 0.01). CONCLUSIONS: The present results suggest that neonatal VAS primes the response in girls such that they get a beneficial effect after a subsequent dose of VAS. TRIAL REGISTRATION: Clinicaltrials.gov NCT00168597.


Asunto(s)
Suplementos Dietéticos , Parto/fisiología , Vitamina A/administración & dosificación , Mortalidad del Niño , Preescolar , Femenino , Estudios de Seguimiento , Guinea Bissau/epidemiología , Humanos , Lactante , Recién Nacido , Masculino , Vitamina A/uso terapéutico , Vitaminas
18.
Br J Nutr ; 105(12): 1819-22, 2011 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-21294931

RESUMEN

Vitamin A treatment reduces mortality during acute measles infection, and vitamin A supplementation (VAS) to children above 6 months of age may reduce the incidence of measles infection. The effect of VAS at birth on measles incidence is unknown. In a randomised placebo-controlled trial in Guinea-Bissau, normal-birth-weight newborns were randomised to 50 000 IU (15 mg) VAS or placebo. During the trial, a measles epidemic occurred. We linked data from the trial with data from the measles infection surveillance and studied the effect of VAS on the measles incidence before 12 months of age in both sexes. A total of 165 measles cases were identified among the 4183 children followed from 28 d of age. Up to 6 months of age, the incidence rate ratio of measles for VAS compared with placebo was 0·54 (95 % CI 0·25, 1·15) among boys and 1·57 (95 % CI 0·80, 3·08) among girls (test of interaction, P = 0·04). The corresponding figures at 12 months were 0·67 (95 % CI 0·43, 1·05) and 1·17 (95 % CI 0·76, 1·79) (test of interaction, P = 0·08). VAS compared with placebo tended to be associated with less measles hospitalisation or death during the first 6 months of life in boys (P = 0·06), but not in girls. VAS at birth may affect the susceptibility to measles infection during the first 6 months of life in a sex-differential manner.


Asunto(s)
Suplementos Dietéticos , Sarampión/prevención & control , Vitamina A/administración & dosificación , Epidemias , Femenino , Guinea Bissau/epidemiología , Hospitalización/estadística & datos numéricos , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Sarampión/sangre , Sarampión/epidemiología , Vacuna Antisarampión , Vigilancia de la Población/métodos , Modelos de Riesgos Proporcionales , Factores Sexuales
19.
Int J Tuberc Lung Dis ; 15(2): 251-6, i, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21219690

RESUMEN

OBJECTIVE: To evaluate the level and prognostic value of procalcitonin (PCT) in a West African out-patient cohort with pulmonary tuberculosis (PTB). METHOD: Patients were clinically scored (TB score), grouped into severity classes (SCs) upon diagnosis and followed for 12 months. Patients were categorised by comparisons of severity class (SC I+II or SC III) and levels of PCT and C-reactive protein (CRP) at diagnosis. Fifty healthy volunteers from the study area were used as controls. The association with TB score was explored using Spearman's rank correlation test. Survival curves stratified after baseline levels of PCT and CRP were compared using the log-rank test. RESULTS: We included 218 patients in the study. PCT and CRP levels were low, but were significantly higher in patients than in controls (P < 0.001), and were higher for SC III compared to SC I+II patients (P = 0.021 for PCT, P < 0.001 for CRP). Human immunodeficiency virus (HIV) status did not influence results. We found positive correlations between both PCT and CRP and TB score. There was a significantly increased risk of mortality with increasing baseline PCT (P = 0.01), whereas high CRP did not predict mortality rate (P = 0.887). CONCLUSION: In West African PTB patients, PCT levels were low but increased significantly with increasing severity of disease, and can predict mortality risk.


Asunto(s)
Calcitonina/sangre , Precursores de Proteínas/sangre , Tuberculosis Pulmonar/sangre , Adulto , Biomarcadores/sangre , Proteína C-Reactiva/análisis , Péptido Relacionado con Gen de Calcitonina , Estudios de Casos y Controles , Distribución de Chi-Cuadrado , Suplementos Dietéticos , Femenino , Guinea Bissau/epidemiología , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Pacientes Ambulatorios , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Índice de Severidad de la Enfermedad , Tasa de Supervivencia , Factores de Tiempo , Resultado del Tratamiento , Tuberculosis Pulmonar/diagnóstico , Tuberculosis Pulmonar/tratamiento farmacológico , Tuberculosis Pulmonar/mortalidad , Regulación hacia Arriba , Vitamina D/uso terapéutico
20.
J Infect Dis ; 202 Suppl: S243-51, 2010 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-20684711

RESUMEN

BACKGROUND: Prophylactic vitamin A supplementation (VAS) reduces mortality and may reduce morbidity associated with diarrhea in children >6 months of age. Rotavirus is the most common cause of acute dehydrating diarrhea among children worldwide. METHODS: In a randomized placebo-controlled study of 50,000 IU of vitamin A versus placebo given with bacille Calmette-Guérin vaccine at birth, 287 infants were followed up with weekly interviews and stool sample obtainment to test the hypothesis that VAS reduced the risk of rotavirus infection. RESULTS: VAS was associated with increased risk of rotavirus infection and diarrhea (incidence rate ratio [IRR] of infection, 1.72 [95% confidence interval (CI), 1.04-2.85]; IRR of diarrhea, 3.74 [95% CI, 1.40-9.98]) among children <6 months of age. There was no effect in older children. VAS had a beneficial effect on nonrotavirus diarrhea in boys <6 months of age (IRR, 0.51; 95% CI, 0.27-0.95) and a detrimental effect in girls >6 months of age (IRR, 1.84; 95% CI, 0.96-3.55). CONCLUSION: VAS at birth did not reduce rotavirus morbidity. The effect of VAS on nonrotavirus diarrhea may differ by sex, being more beneficial in boys. Clinical trials registration. NCT00168597 .


Asunto(s)
Vacuna BCG/administración & dosificación , Diarrea/prevención & control , Infecciones por Rotavirus/prevención & control , Vitamina A/uso terapéutico , Vitaminas/uso terapéutico , Factores de Edad , Diarrea/epidemiología , Diarrea/virología , Brotes de Enfermedades/prevención & control , Femenino , Guinea Bissau/epidemiología , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Infecciones por Rotavirus/epidemiología , Factores Sexuales , Vitamina A/administración & dosificación , Vitaminas/administración & dosificación
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