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1.
Clin Infect Dis ; 72(10): e596-e603, 2021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-32949460

RESUMO

BACKGROUND: Between 2002 and 2014, Guinea-Bissau had 17 national campaigns with oral polio vaccine (OPV) as well as campaigns with vitamin A supplementation (VAS), measles vaccine (MV), and H1N1 influenza vaccine. We examined the impact of these campaigns on child survival. METHODS: We examined the mortality rate between 1 day and 3 years of age of all children in the study area. We used Cox models with age as underlying time to calculate adjusted mortality rate ratios (MRRs) between "after-campaign" mortality and "before-campaign" mortality, adjusted for temporal change in mortality and stratified for season at risk. RESULTS: Mortality was lower after OPV-only campaigns than before, with an MRR for after-campaign vs before-campaign being 0.75 (95% confidence interval [CI], .67-.85). Other campaigns did not have similar effects, the MRR being 1.22 (95% CI, 1.04-1.44) for OPV + VAS campaigns, 1.39 (95% CI, 1.20-1.61) for VAS-only campaigns, 1.32 (95% CI, 1.09-1.60) for MV + VAS campaigns, and 1.13 (95% CI, .86-1.49) for the H1N1 campaign. Thus, all other campaigns differed significantly from the effect of OPV-only campaigns. Effects did not differ for trivalent, bivalent, or monovalent strains of OPV. With each additional campaign of OPV only, the mortality rate declined further (MRR, 0.86 [95% CI, .81-.92] per campaign). With follow-up to 3 years of age, the number needed to treat to save 1 life with the OPV-only campaign was 50 neonates. CONCLUSIONS: OPV campaigns can have a much larger effect on child survival than otherwise assumed. Stopping OPV campaigns in low-income countries as part of the endgame for polio infection may increase child mortality.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Poliomielite , Criança , Mortalidade da Criança , Guiné-Bissau , Humanos , Lactente , Recém-Nascido , Poliomielite/epidemiologia , Poliomielite/prevenção & controle , Vacina Antipólio Oral , Vacinação
2.
Sex Transm Infect ; 97(1): 51-55, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32345631

RESUMO

OBJECTIVES: Complications from sexually transmitted infections (STIs) can result in severe morbidity and mortality. To date, no STI population studies have been conducted on the Bijagos Islands, Guinea Bissau. Our objective was to estimate the prevalence of and identify risk factors for Chlamydia trachomatis (Ct), Neisseria gonorrhoea (Ng), Mycoplasma genitalium (Mg), Trichomonas vaginalis (Tv) and Treponema pallidum (Tp) on Bubaque, the most populated island. METHODS: A cross-sectional survey was conducted on the island of Bubaque among people aged 16-49 years. Participants were asked to answer a questionnaire on STI risk factors, to provide urine samples (men and women) and vaginal swabs (women) for PCR testing for Ct, Ng, Mg and Tv, and to provide dry blood spots for Tp particle agglutination assays. Data were analysed to estimate the prevalence of STIs and logistic regression was used to identify risk factors. RESULTS: In total, 14.9% of participants were found to have a curable STI, with the highest prevalence being observed for Tv (5.9%) followed by Ct (3.8%), Ng (3.8%), Mg (1.9%) and Tp (0.8%). Significant risk factors for having any STI included being female, younger age and concurrent partnership. Having had a previous STI that was optimally treated was a protective factor. CONCLUSIONS: This study demonstrates that there is a considerable burden of STI on the Bijagos Islands, stressing the need for diagnostic testing to facilitate early detection and treatment of these pathogens to stop ongoing transmission. Moreover, these results indicate the need to conduct further research into the STI burden on the Bijagos Islands to help inform and develop a national STI control strategy.


Assuntos
Infecções Sexualmente Transmissíveis/epidemiologia , Adolescente , Adulto , Infecções por Chlamydia/epidemiologia , Chlamydia trachomatis , Estudos Transversais , DNA/urina , Feminino , Gonorreia/epidemiologia , Guiné-Bissau/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Infecções por Mycoplasma/epidemiologia , Mycoplasma genitalium , Neisseria gonorrhoeae , Prevalência , Fatores de Risco , Sífilis/epidemiologia , Treponema pallidum , Vaginite por Trichomonas/epidemiologia , Trichomonas vaginalis , Adulto Jovem
3.
Infection ; 49(4): 631-643, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33528814

RESUMO

PURPOSE: To estimate the life expectancy (LE) of HIV-infected patients in the West African country Guinea-Bissau and compare it with the background population. METHODS: Using data from the largest HIV outpatient clinic at the Hospital Nacional Simão Mendes in the capital Bissau, a retrospective observational cohort study was performed. The study included patients attending the clinic between June 2005 and January 2018. A total of 8958 HIV-infected patients were included. In the analysis of the background population, a total of 109,191 people were included. LE incorporating loss to follow-up (LTFU) was estimated via Kaplan-Meier estimators using observational data on adult HIV-infected patients and background population. RESULTS: The LE of 20-year-old HIV-infected patients was 9.8 years (95% CI 8.3-11.5), corresponding to 22.3% (95% CI 18.5-26.7%) of the LE of the background population. (LE for 20-year-olds in the background population was 44.0 years [95% CI 43.0-44.9].) Patients diagnosed with CD4 cell counts below 200 cells/µL had a LE of 5.7 years (95% CI 3.6-8.2). No increase in LE with later calendar period of diagnosis was observed. CONCLUSIONS: LE was shown to be markedly lower among HIV-infected patients compared with the background population. While other settings have shown marked improvements in prognosis of HIV-infected patients in recent years, no improvement in Bissau was observed over time (9.8 years (95% CI 7.6-12.2) and 9.9 years (95% CI 7.6-12.1) for the periods 2005-2010 and 2014-2016, respectively).


Assuntos
Infecções por HIV , Expectativa de Vida , Adulto , Guiné-Bissau/epidemiologia , Infecções por HIV/epidemiologia , Hospitais , Humanos , Estudos Retrospectivos , Adulto Jovem
4.
Artigo em Inglês | MEDLINE | ID: mdl-31907183

RESUMO

Higher chloroquine doses can effectively treat up to 93 to 96% of malaria infections caused by Plasmodium falciparum carrying the resistance-conferring chloroquine resistance transporter (pfcrt) 76T allele. The tolerability of 50 (double the standard dose) and 70 mg/kg total chloroquine doses were assessed in this study. Fifteen 4- to 8-year-old children with uncomplicated malaria were given 10 mg/kg of chloroquine twice daily for 2 days and 5 mg/kg twice daily on the third day. Fifteen additional children were given 5 mg/kg twice daily for 2 more days. Chloroquine concentrations, blood pressure, electrocardiograms (ECGs), parasite density, and adverse events were assessed until day 28. Both dosages were well tolerated, and symptoms resolved by day 3 in parallel with increasing chloroquine concentrations. The median corrected QT (QTc) interval was 12 to 26 ms higher at expected peak concentrations than at day 0 (P < 0.001). Pfcrt 76T was associated with delayed parasite clearance. Day 28 clinical and parasitological responses against P. falciparum with pfcrt 76T were 57% (4/7) and 67% (4/6) after treatment with 50 and 70 mg/kg, respectively. Dosages were well tolerated, and no severe cardiac adverse events occurred. The QTc interval increase was similar to that found in adults taking 25 mg/kg of chloroquine. (This study has been registered at ClinicalTrials.gov under identifier NCT01814423.).


Assuntos
Antimaláricos/administração & dosagem , Cloroquina/administração & dosagem , Resistência a Medicamentos/genética , Malária Falciparum/tratamento farmacológico , Proteínas de Membrana Transportadoras/genética , Plasmodium falciparum/efeitos dos fármacos , Proteínas de Protozoários/genética , Antimaláricos/efeitos adversos , Criança , Pré-Escolar , Cloroquina/efeitos adversos , Relação Dose-Resposta a Droga , Eletrocardiografia , Feminino , Expressão Gênica , Guiné-Bissau , Humanos , Síndrome do QT Longo/induzido quimicamente , Síndrome do QT Longo/diagnóstico , Síndrome do QT Longo/fisiopatologia , Malária Falciparum/parasitologia , Masculino , Proteínas de Membrana Transportadoras/metabolismo , Carga Parasitária , Plasmodium falciparum/genética , Plasmodium falciparum/crescimento & desenvolvimento , Proteínas de Protozoários/metabolismo , Resultado do Tratamento
5.
Trop Med Int Health ; 25(2): 255-263, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31746078

RESUMO

OBJECTIVE: Hepatitis B virus (HBV) and hepatitis C virus (HCV) are prevalent in West Africa. To address the WHO 2030 goals of a 90% reduction in incidence and a 65% reduction in mortality for both infections, we assessed the prevalence of HBV and HCV from surveys in the general population. METHODS: Participants in this cross-sectional survey were included from randomly selected houses in a demographic surveillance site in Bissau, Guinea-Bissau. Participants were interviewed and had a blood sample drawn for viral analyses (HBsAg, anti-HBs, anti-HBc, anti-HCV and HCV RNA). Risk factors of HBV and HCV infection were determined by binomial regression adjusted for sex and age. RESULTS: A total of 2715 participants were included in this study. The overall HBsAg prevalence was 18.7% (95% CI: 17.3-20.2%). HBsAg was associated with male sex (adjusted risk ratio (aRR): 1.64), and prevalence decreased with age >34 years. HBV exposure was found in 91.9% of participants. Although 72.6% of individuals without sexual debut had been exposed to HBV, ever engaging in a sexual relationship was associated with higher risk of HBV exposure (aRR 1.18). The anti-HCV prevalence was 0.5% (95% CI: 0.3-0.9%), and 78.6% of those had detectable HCV RNA. Risk factors for anti-HCV sero-positivity were age above 55 (aRR 10.60), a history of blood transfusion (aRR 5.07) and being in a polygamous marriage (aRR 3.52). CONCLUSION: In Guinea-Bissau initiatives to implement treatment and widespread testing are needed to reach the WHO 2030 goals.


OBJECTIF: Le virus de l'hépatite B (VHB) et le virus de l'hépatite C (VHC) sont répandus en Afrique de l'Ouest. Pour atteindre les objectifs de 2030 de l'OMS d'une réduction de 90% de l'incidence et de 65% de la mortalité pour les deux infections, nous avons évalué la prévalence du VHB et du VHC à partir d'enquêtes dans la population générale. MÉTHODES: Les participants inclus dans cette enquête transversale provenaient de foyers sélectionnés au hasard dans un site de surveillance démographique à Bissau, en Guinée-Bissau. Les participants ont été interrogés et ont subi un prélèvement d'échantillon de sang pour des analyses virales (HBsAg, anti-HBs, anti-HBc, anti-HCV et ARN du HCV). Les facteurs de risque d'infection par le VHB et le VHC ont été déterminés par la régression binomiale ajustée en fonction du sexe et de l'âge. RÉSULTATS: 2.715 participants ont été inclus dans cette étude. La prévalence globale de l'HBsAg était de 18,7% (IC95%: 17,3-20,2%). L'HBsAg était associé au sexe masculin (rapport de risque ajusté (aRR): 1,64), et la prévalence diminuait avec l'âge >34 ans. Une exposition au VHB a été observée chez 91,9% des participants. Bien que 72,6% des personnes sans début d'activité sexuelle aient été exposées au VHB, le fait de s'engager dans des relations sexuelles était associé à un risque plus élevé d'exposition au VHB (aRR: 1,18). La prévalence d'anti-VHC était de 0,5% (IC95%: 0,3-0,9%) et 78,6% d'entre eux avaient de l'ARN du VHC détectable. Les facteurs de risque de séropositivité anti-VHC étaient l'âge de plus de 55 ans (aRR: 10,60), les antécédents de transfusion sanguine (aRR: 5,07) et le fait d'être dans un mariage polygame (aRR: 3,52). CONCLUSION: En Guinée-Bissau, des initiatives pour mettre en œuvre un traitement et des tests généralisés sont nécessaires pour atteindre les objectifs de l'OMS 2030.


Assuntos
Hepatite B/epidemiologia , Hepatite C/epidemiologia , Adulto , Estudos Transversais , Feminino , Guiné-Bissau/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco
6.
Malar J ; 19(1): 412, 2020 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-33203419

RESUMO

BACKGROUND: Malaria remains a significant public health problem in Guinea-Bissau, West Africa. Government control measures include bed net distribution campaigns, however, local knowledge, attitudes and practices towards bed nets and malaria are uncharacterized on the remote Bijagos Archipelago. METHODS: Knowledge, attitude and practice questionnaires were conducted with household heads, aiming to explore the understanding of malaria and factors influencing bed net uptake and usage. Nets were observed in situ to appraise net quality and behaviour. All 14 villages and one semi-urban neighbourhood on Bubaque Island were included. One in 5 households containing school-aged children were randomly selected. RESULTS: Of 100 participants, 94 were aware of malaria and 66 of those considered it a significant or severe problem, primarily because of its impact on health and income. Transmission, symptoms and risk factors were well known, however, 28.0% of participants felt under-informed. Some 80.0% reported contact with distribution campaigns, with inter-village variability. Campaign contact was associated with feeling well informed (OR 3.44; P = 0.024) and inversely with perceiving malaria a household (OR 0.18; P = 0.002) or regional problem (OR 0.25; P = 0.018). Every household contained nets; every identifiable example was a long-lasting insecticide-treated net (LLIN), however, 23.0% of households contained at least one expired net. Replacements were in demand; 89.0% of households reported that all residents used nets, and average occupancy was 2.07 people per net; 65.2% stated that the repurposing of bed nets was common. Correctly using bed nets, defined by age, integrity and demonstration, was 35.0% and strongly associated with completing intermittent preventative treatment in pregnancy (RR 3.63; P = 0.014). CONCLUSIONS: Knowledge of malaria is good in these communities. Bed nets are used widely and are valued for their role in preventing malaria. However, their use is frequently sub-optimal and offers a target for improving malaria control by adapting popular distribution campaigns to provide more education alongside fresh LLINs. The impact of this could be significant as LLINs represent the mainstay of malaria prevention in Guinea-Bissau; however, the persistence of malaria despite the high uptake of LLINs seen in this study suggests that novel supplementary approaches must also be considered.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Malária/psicologia , Controle de Mosquitos/estatística & dados numéricos , Mosquiteiros/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Guiné-Bissau , Humanos , Ilhas , Masculino , Pessoa de Meia-Idade , Adulto Jovem
7.
Malar J ; 19(1): 27, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31941507

RESUMO

BACKGROUND: Bubaque is the most populous island of the Bijagos archipelago, a group of malaria-endemic islands situated off the coast of Guinea-Bissau, West Africa. Malaria vector control on Bubaque relies almost exclusively on the use of long-lasting insecticidal nets (LLINs). However, there is little information on local vector bionomics and insecticide resistance. METHODS: A survey of mosquito species composition was performed at the onset of the wet season (June/July) and the beginning of the dry season (November/December). Sampling was performed using indoor adult light-traps and larval dipping. Anopheles mosquitoes were identified to species level and assessed for kdr allele frequency by TaqMan PCR. Females were analysed for sporozoite positivity by CSP-ELISA. Resistance to permethrin and α-cypermethrin was measured using the CDC-bottle bioassay incorporating the synergist piperonyl-butoxide. RESULTS: Several Anopheles species were found on the island, all belonging to the Anopheles gambiae sensu lato (s.l.) complex, including An. gambiae sensu stricto, Anopheles coluzzii, Anopheles melas, and An. gambiae/An. coluzzii hybrids. Endophagic Anopheles species composition and abundance showed strong seasonal variation, with a majority of An. gambiae (50% of adults collected) caught in June/July, while An. melas was dominant in November/December (83.9% of adults collected). Anopheles gambiae had the highest sporozoite rate in both seasons, with infection rates of 13.9% and 20% in June/July and November/December, respectively. Moderate frequencies of the West African kdr allele were found in An. gambiae (36%), An. coluzzii (35%), An. gambiae/An. coluzzii hybrids (42%). Bioassays suggest moderate resistance to α-cypermethrin, but full susceptibility to permethrin. CONCLUSIONS: The island of Bubaque maintained an An. gambiae s.l. population in both June/July and November/December. Anopheles gambiae was the primary vector at the onset of the wet season, while An. melas is likely to be responsible for most dry season transmission. There was moderate kdr allele frequency and synergist assays suggest likely metabolic resistance, which could reduce the efficacy of LLINs. Future control of malaria on the islands should consider the seasonal shift in mosquito species, and should employ continuous monitoring for insecticide resistance.


Assuntos
Anopheles/classificação , Resistência a Inseticidas , Malária/transmissão , Mosquitos Vetores/classificação , Animais , Anopheles/enzimologia , Anopheles/genética , Bioensaio/métodos , DNA/isolamento & purificação , Feminino , Técnicas de Genotipagem , Guiné-Bissau , Resistência a Inseticidas/genética , Ilhas , Malária/prevenção & controle , Mosquitos Vetores/enzimologia , Mosquitos Vetores/genética , Projetos Piloto , Estações do Ano , Inquéritos e Questionários , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética
8.
Demography ; 57(5): 1705-1726, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32914335

RESUMO

Neonatal deaths (occurring within 28 days of birth) account for close to one-half of all deaths among children under age 5 worldwide. In most low- and middle-income countries, data on neonatal deaths come primarily from household surveys. We conducted a validation study of survey data on neonatal mortality in Guinea-Bissau (West Africa). We used records from an urban health and demographic surveillance system (HDSS) that monitors child survival prospectively as our reference data set. We selected a stratified sample of 599 women aged 15-49 among residents of the HDSS and collected the birth histories of 422 participants. We cross-tabulated survey and HDSS data. We used a mathematical model to investigate biases in survey estimates of neonatal mortality. Reporting errors in survey data might lead to estimates of the neonatal mortality rate that are too high, which may limit our ability to track progress toward global health objectives.


Assuntos
Inquéritos Epidemiológicos/normas , Mortalidade Perinatal/tendências , População Urbana/estatística & dados numéricos , Adolescente , Adulto , Coleta de Dados/normas , Feminino , Guiné-Bissau/epidemiologia , Humanos , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Fatores Socioeconômicos , Adulto Jovem
9.
Trop Med Int Health ; 24(2): 166-174, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30430696

RESUMO

OBJECTIVE: Improving civil registration and vital statistics (CRVS) systems is essential to monitoring health objectives locally and globally. The barriers to birth and particularly death registration in low- and middle-income countries are however poorly understood. METHODS: We conducted a survey among women of reproductive age in Bissau, the capital of Guinea-Bissau. We asked women with a birth in the past two years whether their child had been registered and had obtained a birth certificate. We elicited the sources of information about birth registration and asked respondents to list their reasons for (not) registering a birth. If their child had died, we asked similar questions about death registration. RESULTS: Most women (86%) had received messages about birth registration, but few women whose child had died had heard about the need to register deaths (22%). The primary sources of information about birth registration were messages broadcast on the radio or displayed at health facilities. Information about death registration was primarily obtained through informal social networks. Only 16% of births, and 2% of deaths, had been registered. The main barriers to birth registration were administrative pre-requisites and paternal absence. The main reasons for not registering a death were lack of knowledge about death registration and lack of perceived benefits. CONCLUSION: Strengthening CRVS systems requires addressing the specific barriers preventing birth and death registration. In Bissau, interventions to improve knowledge about death registration are needed. Simplifying registration procedures, as well as providing additional incentives, might help improve the coverage of birth registration.


Assuntos
Mortalidade Infantil , Sistema de Registros/estatística & dados numéricos , Estatísticas Vitais , Declaração de Nascimento , Coeficiente de Natalidade , Atestado de Óbito , Feminino , Guiné-Bissau , Humanos , Lactente , Recém-Nascido , Masculino , Inquéritos e Questionários
10.
Malar J ; 18(1): 252, 2019 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-31349834

RESUMO

BACKGROUND: Large-scale surveillance of molecular markers of anti-malarial drug resistance is an attractive method of resistance monitoring, to complement therapeutic efficacy studies in settings where the latter are logistically challenging. METHODS: Between 2014 and 2017, this study sampled malaria rapid diagnostic tests (RDTs), used in routine clinical care, from two health centres in Bissau, Guinea-Bissau. In order to obtain epidemiological insights, RDTs were collected together with patient data on age and sex. A subset of positive RDTs from one of the two sites (n = 2184) were tested for Plasmodium DNA content. Those testing positive for Plasmodium DNA by PCR (n = 1390) were used for library preparation, custom designed dual indexing and next generation Miseq targeted sequencing of Plasmodium falciparum genes pfcrt, pfmdr1, pfdhfr, pfdhps and pfk13. RESULTS: The study found a high frequency of the pfmdr1 codon 86N at 88-97%, a significant decrease of the pfcrt wildtype CVMNK haplotype and elevated levels of the pfdhfr/pfdhps quadruple mutant ranging from 33 to 51% between 2014 and 2017. No polymorphisms indicating artemisinin tolerance were discovered. The demographic data indicate a large proportion of young adults (66%, interquartile range 11-28 years) presenting with P. falciparum infections. While a total of 5532 gene fragments were successfully analysed on a single Illumina Miseq flow cell, PCR-positivity from the library preparation varied considerably from 13 to 87% for different amplicons. Furthermore, pre-screening of samples for Plasmodium DNA content proved necessary prior to library preparation. CONCLUSIONS: This study serves as a proof of concept for using leftover clinical material (used RDTs) for large-scale molecular surveillance, encompassing the inherent complications regarding to methodology and analysis when doing so. Factors such as RDT storage prior to DNA extraction and parasitaemia of the infection are likely to have an effect on whether or not parasite DNA can be successfully analysed, and are considered part of the reason the data yield is suboptimal. However, given the necessity of molecular surveillance of anti-malarial resistance in settings where poor infrastructure, poor economy, lack of educated staff and even surges of political instability remain major obstacles to performing clinical studies, obtaining the necessary data from used RDTs, despite suboptimal output, becomes a feasible, affordable and hence a justifiable method.


Assuntos
Testes Diagnósticos de Rotina/estatística & dados numéricos , Monitoramento Epidemiológico , Malária Falciparum/diagnóstico , Plasmodium falciparum/genética , Estudo de Prova de Conceito , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Guiné-Bissau , Humanos , Lactente , Recém-Nascido , Masculino , Adulto Jovem
11.
J Trop Pediatr ; 65(5): 446-456, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30590828

RESUMO

BACKGROUND: In addition to vaccines' specific effects, vaccines may have non-specific effects (NSEs) altering the susceptibility to unrelated infections. Non-live vaccines have been associated with negative NSEs. In 2010, a campaign with the non-live H1N1-influenza vaccine targeted children 6-59 months in Guinea-Bissau. METHODS: Bandim Health Project runs a health and demographic surveillance system site in Guinea-Bissau. Using a Cox proportional hazards model, we compared all-cause consultation rates after vs. before the campaign, stratified by participation status. RESULTS: Among 10 290 children eligible for the campaign, 60% had participated, 18% had not and for 22% no information was obtained. After the H1N1 campaign, the consultation rates tended to decline less for participants [HR = 0.80 (95% confidence interval, CI: 0.75; 0.85)] than for non-participants [HR = 0.68 (95% CI: 0.58; 0.79)], p = 0.06 for same effect. CONCLUSION: The decline in the vaccinated group may have been smaller than the decline in the non-vaccinated group consistent with H1N1-vaccine increasing susceptibility to unrelated infections.


Assuntos
Programas de Imunização , Vírus da Influenza A Subtipo H1N1 , Vacinas contra Influenza/efeitos adversos , Influenza Humana/prevenção & controle , Visita a Consultório Médico/estatística & dados numéricos , Pré-Escolar , Suplementos Nutricionais , Feminino , Guiné-Bissau , Humanos , Lactente , Masculino , Modelos de Riscos Proporcionais , Vitamina A/uso terapêutico , Vitaminas/uso terapêutico
12.
Clin Infect Dis ; 66(10): 1573-1580, 2018 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-29177407

RESUMO

Background: In addition to protecting against measles, measles vaccine (MV) may have beneficial nonspecific effects. We tested the effect of an additional early MV on mortality and measles antibody levels. Methods: Children aged 4-7 months at rural health and demographic surveillance sites in Burkina Faso and Guinea-Bissau were randomized 1:1 to an extra early standard dose of MV (Edmonston-Zagreb strain) or no extra MV 4 weeks after the third diphtheria-tetanus-pertussis-hepatitis B-Haemophilus influenzae type b vaccine. All children received routine MV at 9 months. We assessed mortality through home visits and compared mortality from enrollment to age 3 years using Cox proportional hazards models, censoring for subsequent nontrial MV. Subgroups of participants had blood sampled to assess measles antibody levels. Results: Among 8309 children enrolled from 18 July 2012 to 3 December 2015, we registered 145 deaths (mortality rate: 16/1000 person-years). The mortality was lower than anticipated and did not differ by randomization group (hazard ratio, 1.05; 95% confidence interval, 0.75-1.46). At enrollment, 4% (16/447) of children in Burkina Faso and 21% (90/422) in Guinea-Bissau had protective measles antibody levels. By age 9 months, no measles-unvaccinated/-unexposed child had protective levels, while 92% (306/333) of early MV recipients had protective levels. At final follow-up, 98% (186/189) in the early MV group and 97% (196/202) in the control group had protective levels. Conclusions: Early MV did not reduce all-cause mortality. Most children were susceptible to measles infection at age 4-7 months and responded with high antibody levels to early MV. Clinical Trials Registration: NCT01644721.


Assuntos
Anticorpos Antivirais/sangue , Esquemas de Imunização , Vacina contra Sarampo/administração & dosagem , Vacina contra Sarampo/imunologia , Sarampo/prevenção & controle , Burkina Faso/epidemiologia , Feminino , Guiné-Bissau/epidemiologia , Humanos , Lactente , Masculino , Sarampo/sangue , Sarampo/imunologia , Vírus do Sarampo/imunologia
13.
Malar J ; 17(1): 91, 2018 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-29471822

RESUMO

BACKGROUND: Plasmodium falciparum malaria remains a major health burden and genomic research represents one of the necessary approaches for continued progress towards malaria control and elimination. Sample acquisition for this purpose is troublesome, with the majority of malaria-infected individuals living in rural areas, away from main infrastructure and the electrical grid. The aim of this study was to describe a low-tech procedure to sample P. falciparum specimens for direct whole genome sequencing (WGS), without use of electricity and cold-chain. METHODS: Venous blood samples were collected from malaria patients in Bandim, Guinea-Bissau and leukocyte-depleted using Plasmodipur filters, the enriched parasite sample was spotted on Whatman paper and dried. The samples were stored at ambient temperatures and subsequently used for DNA-extraction. Ratios of parasite:human content of the extracted DNA was assessed by qPCR, and five samples with varying parasitaemia, were sequenced. Sequencing data were used to analyse the sample content, as well as sample coverage and depth as compared to the 3d7 reference genome. RESULTS: qPCR revealed that 73% of the 199 samples were applicable for WGS, as defined by a minimum ratio of parasite:human DNA of 2:1. WGS revealed an even distribution of sequence data across the 3d7 reference genome, regardless of parasitaemia. The acquired read depths varied from 16 to 99×, and coverage varied from 87.5 to 98.9% of the 3d7 reference genome. SNP-analysis of six genes, for which amplicon sequencing has been performed previously, confirmed the reliability of the WGS-data. CONCLUSION: This study describes a simple filter paper based protocol for sampling P. falciparum from malaria patients for subsequent direct WGS, enabling acquisition of samples in remote settings with no access to electricity.


Assuntos
Dessecação , Eritrócitos/parasitologia , Plasmodium falciparum/genética , Manejo de Espécimes/métodos , Sequenciamento Completo do Genoma/métodos , DNA de Protozoário/química , DNA de Protozoário/genética , DNA de Protozoário/isolamento & purificação , Guiné-Bissau , Humanos , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA , Temperatura
14.
BMC Public Health ; 18(1): 984, 2018 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-30086732

RESUMO

BACKGROUND: Measles vaccine (MV) may protect against non-measles mortality. We tested whether survival depended on age of measles vaccination. METHODS: Bandim Health Project follows children under 5 years of age through a Health and Demographic Surveillance System in rural Guinea-Bissau. Children aged 6-36 months with a vaccination card inspected were followed to the next visit or for a maximum of 6 months. In Cox proportional-hazards models adjusted for age and village cluster, we compared the survival of children vaccinated with MV early (< 9 months), as recommended (9-11 months) or late (> 12+ months) with the survival of measles-unvaccinated children. Among measles-vaccinated children, we modelled the effect of age at measles vaccination linearly to assess mortality changes per month increase in vaccination age. RESULTS: From 1999 to 2006, 14,813 children (31,725 observations) were included. Children vaccinated with MV had a Hazard Ratio (HR) of 0.76 (95% CI: 0.63-0.91) compared with measles-unvaccinated children; censoring measles deaths did not change the results (HR = 0.79 (0.65-0.95)). For early MV the HR was 0.68 (0.53-0.87), for MV as recommended the HR was 0.77 (0.62-0.96) and for late MV the HR was 0.86 (0.67-1.11). Limiting the analysis to measles-vaccinated children, age at measles vaccination was associated with a 2.6% (0.4-5.1%) increase in mortality per month increase in vaccination age. CONCLUSION: Early MV was associated with a large survival advantage. The current policy to increase vaccination age, when measles control improves, may not optimize the impact of MV on child survival.


Assuntos
Fatores Etários , Mortalidade da Criança , Esquemas de Imunização , Vacina contra Sarampo/administração & dosagem , Vacinação/mortalidade , Pré-Escolar , Feminino , Guiné-Bissau/epidemiologia , Humanos , Lactente , Masculino , Sarampo/mortalidade , Sarampo/prevenção & controle , Modelos de Riscos Proporcionais
15.
Clin Infect Dis ; 65(7): 1183-1190, 2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29579158

RESUMO

Background: BCG vaccine may reduce overall mortality by increasing resistance to nontuberculosis infections. In 2 randomized trials in Guinea-Bissau of early BCG-Denmark (Statens Serum Institut) given to low-weight (LW) neonates (<2500 g at inclusion) to reduce infant mortality rates, we observed a very beneficial effect in the neonatal period. We therefore conducted the present trial to test whether early BCG-Denmark reduces neonatal mortality by 45%. We also conducted a meta-analysis of the 3 BCG-Denmark trials. Methods: In 2008-2013, we randomized LW neonates to "early BCG-Denmark" (intervention group; n = 2083) or "control" (local policy for LW and no BCG-Denmark; n = 2089) at discharge from the maternity ward or at first contact with the health center. The infants were randomized (1:1) without blinding in blocks of 24. Data was analyzed in Cox hazards models providing mortality rate ratios (MRRs). We had prespecified an analysis censoring follow-up at oral poliovirus vaccine campaigns. Results: Early administration of BCG-Denmark was associated with a nonsignificant reduction in neonatal mortality rate (MRR, 0.70; 95% confidence interval [CI], .47-1.04) and a 34% reduction (0.66; .44-1.00) when censoring for oral poliovirus vaccine campaigns. There was no reduction in mortality rate for noninfectious diseases, but a 43% reduction in infectious disease mortality rate (MRR, 0.57; 95% CI, .35-.93). A meta-analysis of 3 BCG trials showed that early BCG-Denmark reduced mortality by 38% (MRR, 0.62; 95% CI, .46-.83) within the neonatal period and 16% (0.84; .71-1.00) by age 12 months. Conclusion: Early administration of BCG-Denmark in LW infants is associated with major reductions in mortality rate. It is important that all LW infants receive early BCG in areas with high neonatal mortality rates. Clinical Trials Registration: NCT00625482.


Assuntos
Vacina BCG/administração & dosagem , Vacina BCG/imunologia , Recém-Nascido de Baixo Peso/imunologia , Doenças Transmissíveis/imunologia , Dinamarca , Feminino , Guiné-Bissau , Humanos , Lactente , Mortalidade Infantil , Recém-Nascido , Masculino , Vacina Antipólio Oral/administração & dosagem , Vacina Antipólio Oral/imunologia , Vacinação/métodos
16.
Trop Med Int Health ; 22(7): 846-856, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28464403

RESUMO

OBJECTIVES: In many African countries, child mortality is higher in the rainy season than in the dry season. We investigated the effect of season on child mortality by time periods, sex and age in rural Guinea-Bissau. METHODS: Bandim health project follows children under-five in a health and demographic surveillance system in rural Guinea-Bissau. We compared the mortality in the rainy season (June to November) between 1990 and 2013 with the mortality in the dry season (December to May) in Cox proportional hazards models providing rainy vs. dry season mortality rate ratios (r/d-mrr). Seasonal effects were estimated in strata defined by time periods with different frequency of vaccination campaigns, sex and age (<1 month, 1-11 months, 12-59 months). Verbal autopsies were interpreted using InterVa-4 software. RESULTS: From 1990 to 2013, overall mortality was declined by almost two-thirds among 81 292 children (10 588 deaths). Mortality was 51% (95% ci: 45-58%) higher in the rainy season than in the dry season throughout the study period. The seasonal difference increased significantly with age, the r/d-mrr being 0.94 (0.86-1.03) among neonates, 1.57 (1.46-1.69) in post-neonatal infants and 1.83 (1.72-1.95) in under-five children (P for same effect <0.001). According to the InterVa, malaria deaths were the main reason for the seasonal mortality difference, causing 50% of all deaths in the rainy season, but only if the InterVa included season of death, making the argument self-confirmatory. CONCLUSION: The mortality declined throughout the study, yet rainy season continued to be associated with 51% higher overall mortality.


Assuntos
Mortalidade da Criança , Clima , População Rural/estatística & dados numéricos , Estações do Ano , Fatores Etários , Pré-Escolar , Feminino , Guiné-Bissau , Humanos , Lactente , Recém-Nascido , Masculino , Modelos de Riscos Proporcionais , Fatores Sexuais
17.
J Infect Dis ; 213(8): 1315-21, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26656124

RESUMO

BACKGROUND: Due to development of multidrug-resistant Plasmodium falciparum new antimalarial therapies are needed. In Guinea-Bissau, routinely used triple standard-dose chloroquine remained effective for decades despite the existence of "chloroquine-resistant" P. falciparum. This study aimed to determine the in vivo efficacy of higher chloroquine concentrations against P. falciparum with resistance-conferring genotypes. METHODS: Standard or double-dose chloroquine was given to 892 children aged <15 years with uncomplicated malaria during 3 clinical trials (2001-2008) with ≥ 35 days follow-up. The P. falciparum resistance-conferring genotype (pfcrt 76T) and day 7 chloroquine concentrations were determined. Data were divided into age groups (<5, 5-9, and 10-14 years) because concentrations increase with age when chloroquine is prescribed according to body weight. RESULTS: Adequate clinical and parasitological responses were 14%, 38%, and 39% after standard-dose and 66%, 84%, and 91% after double-dose chloroquine in children aged <5, 5-9, and 10-14 years, respectively, and infected with P. falciparum genotypes conferring chloroquine resistance (n = 195, P < .001). In parallel, median chloroquine concentrations were 471, 688, and 809 nmol/L for standard-dose and 1040, 1494, and 1585 nmol/L for double-dose chloroquine. CONCLUSIONS: Chloroquine resistance is dose dependent and can be overcome by higher, still well-tolerated doses.


Assuntos
Antimaláricos/administração & dosagem , Antimaláricos/uso terapêutico , Cloroquina/administração & dosagem , Cloroquina/uso terapêutico , Malária Falciparum/tratamento farmacológico , Plasmodium falciparum/efeitos dos fármacos , Antimaláricos/farmacologia , Criança , Pré-Escolar , Cloroquina/farmacologia , Resistência a Medicamentos , Feminino , Humanos , Masculino , Proteínas de Membrana Transportadoras/genética , Carga Parasitária , Plasmodium falciparum/genética , Proteínas de Protozoários/genética
18.
Clin Infect Dis ; 63(suppl 5): S312-S321, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27941110

RESUMO

BACKGROUND: If malaria patients who cannot be treated orally are several hours from facilities for injections, rectal artesunate prior to hospital referral can prevent death and disability. The goal is to reduce death from malaria by having rectal artesunate treatment available and used. How best to do this remains unknown. METHODS: Villages remote from a health facility were randomized to different community-based treatment providers trained to provide rectal artesunate in Ghana, Guinea-Bissau, Tanzania, and Uganda. Prereferral rectal artesunate treatment was provided in 272 villages: 109 through community-based health workers (CHWs), 112 via trained mothers (MUMs), 25 via trained traditional healers (THs), and 26 through trained community-chosen personnel (COMs); episodes eligible for rectal artesunate were established through regular household surveys of febrile illnesses recording symptoms eligible for prereferral treatment. Differences in treatment coverage with rectal artesunate in children aged <5 years in MUM vs CHW (standard-of-care) villages were assessed using the odds ratio (OR); the predictive probability of treatment was derived from a logistic regression analysis, adjusting for heterogeneity between clusters (villages) using random effects. RESULTS: Over 19 months, 54 013 children had 102 504 febrile episodes, of which 32% (31 817 episodes) had symptoms eligible for prereferral therapy; 14% (4460) children received treatment. Episodes with altered consciousness, coma, or convulsions constituted 36.6% of all episodes in treated children. The overall OR of treatment between MUM vs CHW villages, adjusting for country, was 1.84 (95% confidence interval [CI], 1.20-2.83; P = .005). Adjusting for heterogeneity, this translated into a 1.67 higher average probability of a child being treated in MUM vs CHW villages. Referral compliance was 81% and significantly higher with CHWs vs MUMs: 87% vs 82% (risk ratio [RR], 1.1 [95% CI, 1.0-1.1]; P < .0001). There were more deaths in the TH cluster than elsewhere (RR, 2.7 [95% CI, 1.4-5.6]; P = .0040). CONCLUSIONS: Prereferral episodes were almost one-third of all febrile episodes. More than one-third of patients treated had convulsions, altered consciousness, or coma. Mothers were effective in treating patients, and achieved higher coverage than other providers. Treatment access was low. CLINICAL TRIALS REGISTRATION: ISRCTN58046240.


Assuntos
Antimaláricos/administração & dosagem , Antimaláricos/uso terapêutico , Malária/tratamento farmacológico , Administração Retal , Artemisininas/administração & dosagem , Artemisininas/uso terapêutico , Artesunato , Pré-Escolar , Agentes Comunitários de Saúde , Feminino , Gana/epidemiologia , Guiné-Bissau/epidemiologia , Humanos , Lactente , Malária/epidemiologia , Masculino , Encaminhamento e Consulta , Tanzânia/epidemiologia , Uganda/epidemiologia
19.
Mol Ecol ; 25(22): 5719-5731, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27661465

RESUMO

Speciation with gene flow may be aided by reduced recombination helping to build linkage between genes involved in the early stages of reproductive isolation. Reduced recombination on chromosome X has been implicated in speciation within the Anopheles gambiae complex, species of which represent the major Afrotropical malaria vectors. The most recently diverged, morphologically indistinguishable, species pair, A. gambiae and Anopheles coluzzii, ubiquitously displays a 'genomic island of divergence' spanning over 4 Mb from chromosome X centromere, which represents a particularly promising candidate region for reproductive isolation genes, in addition to containing the diagnostic markers used to distinguish the species. Very low recombination makes the island intractable for experimental recombination studies, but an extreme hybrid zone in Guinea Bissau offers the opportunity for natural investigation of X-island recombination. SNP analysis of chromosome X hemizygous males revealed: (i) strong divergence in the X-island despite a lack of autosomal divergence; (ii) individuals with multiple-recombinant genotypes, including likely double crossovers and localized gene conversion; (iii) recombination-driven discontinuity both within and between the molecular species markers, suggesting that the utility of the diagnostics is undermined under high hybridization. The largely, but incompletely protected nature of the X centromeric genomic island is consistent with a primary candidate area for accumulation of adaptive variants driving speciation with gene flow, while permitting some selective shuffling and removal of genetic variation.


Assuntos
Anopheles/genética , Ilhas Genômicas , Hibridização Genética , Cromossomo X/genética , Animais , Fluxo Gênico , Genótipo , Guiné-Bissau , Masculino , Polimorfismo de Nucleotídeo Único , Recombinação Genética , Isolamento Reprodutivo
20.
Clin Infect Dis ; 61(6): 950-9, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26060293

RESUMO

BACKGROUND: Previous studies have found that BCG vaccination has nonspecific beneficial effects on child survival, especially among children who developed a BCG scar. These studies have mostly been done in settings with a high scar frequency. In rural Guinea-Bissau, many children do not develop a scar; we tested the hypothesis that among BCG-vaccinated children, a vaccination scar was associated with lower mortality and fewer hospital admissions. METHODS: During 2009-2011, children <5 years of age in villages followed by Bandim Health Project's demographic surveillance system had their scar status assessed at semiannual visits. We compared mortality and hospital admission rates of scar-positive and scar-negative BCG-vaccinated children during 6 months of follow-up in Cox proportional hazards models. RESULTS: Among 15 911 BCG-vaccinated children, only 52% had a scar. There were 106 non-injury-related deaths among scar-positive children and 137 among scar-negative children. The mortality rate ratio (MRR) was 0.74 (95% confidence interval [CI], .56-.96) overall; 0.48 (95% CI, .26-.90) in infancy, 0.69 (95% CI, .45-1.05) in the second year of life, and 0.89 (95% CI, .61-1.31) in the third-fifth year of life. The association between scar positivity and lower mortality differed significantly by cause of death and was strongest for respiratory infections (MRR, 0.20 [95% CI, .07-.55]). There were 99 hospital admissions among scar-positive children and 125 admissions among scar-negative children, resulting in an incidence rate ratio of 0.74 (95% CI, .60-.92). CONCLUSIONS: Among BCG-vaccinated children in a setting with low scar prevalence, having a scar is associated with lower mortality and morbidity. BCG scar prevalence may be an important marker of vaccination program quality.


Assuntos
Vacina BCG/administração & dosagem , Vacina BCG/imunologia , Cicatriz/induzido quimicamente , Cicatriz/epidemiologia , Doenças Transmissíveis/mortalidade , Doenças Transmissíveis/patologia , Hospitalização , Vacina BCG/efeitos adversos , Pré-Escolar , Estudos de Coortes , Feminino , Guiné-Bissau/epidemiologia , Humanos , Incidência , Lactente , Masculino , População Rural , Análise de Sobrevida
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