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The objective of this work is to develop a simple methodology for high resolution crop suitability analysis under current and future climate, easily applicable and useful in Least Developed Countries. The approach addresses both regional planning in the context of climate change projections and pre-emptive short-term rural extension interventions based on same-year agricultural season forecasts, while implemented with off-the-shelf resources. The developed tools are applied operationally in a case-study developed in three regions of Guinea-Bissau and the obtained results, as well as the advantages and limitations of methods applied, are discussed. In this paper we show how a simple approach can easily generate information on climate vulnerability and how it can be operationally used in rural extension services. [ABSTRACT FROM AUTHOR]

Introduction: Though still high, the infant mortality rate in Guinea-Bissau has declined. We aimed to identify risk factors including vaccination coverage, for infant mortality in the rural population of Guinea-Bissau and assess whether these risk factors changed from 1992–3 to 2002–3. Methods: The Bandim Health Project (BHP) continuously surveys children in rural Guinea-Bissau. We investigated the association between maternal and infant factors (especially DTP and measles coverage) and infant mortality. Hazard ratios (HR) were calculated using Cox regression. We tested for interactions with sex, age groups (defined by current vaccination schedule) and cohort to assess whether the risk factors were the same for boys and girls, in different age groups in 1992–3 and in 2002–3. Results: The infant mortality rate declined from 148/1000 person years (PYRS) in 1992–3 to 124/1000 PYRS in 2002–3 (HR = 0.88;95%CI:0.77–0.99); this decline was significant for girls (0.77;0.64–0.94) but not for boys (0.97;0.82–1.15) (p = 0.10 for interaction). Risk factors did not differ significantly by cohort in either distribution or effect. Mortality decline was most marked among girls aged 9–11 months (0.56;0.37–0.83). There was no significant mortality decline for girls 1.5–8 months of age (0.93;0.68–1.28) (p = 0.05 for interaction). DTP and measles coverage increased from 1992–3 to 2002–3. Conclusions: Risk factors did not change with the decline in mortality. Due to beneficial non-specific effects for girls, the increased coverage of measles vaccination may have contributed to the disproportional decline in mortality by sex and age group. [ABSTRACT FROM AUTHOR]

Background: Artemether-lumefantrine (AL) was introduced for treatment of uncomplicated malaria in Guinea-Bissau in 2008. Malaria then resurged and recurrent malaria after treatment with AL and stock-outs of AL were common. This study therefore aimed to assess the efficacy of AL and identify an alternative second line antimalarial. Dihydroartemisinin-piperaquine (DP) was chosen as it has been shown to be safe and efficacious and to reduce the incidence of recurrent malaria. Methods and Findings: In a multicentre randomised open-label non-inferiority clinical trial, AL or DP were given over 3 days to children aged 6 months-15 years with uncomplicated P. falciparum mono-infection. Intake was observed and AL was given with milk. Children were seen on days 0, 1, 2 and 3 and then weekly days 7–42. Recurring P. falciparum were classified as recrudescence or new infections by genotyping. Between November 2012 and July 2015, 312 children were randomised to AL (n = 155) or DP (n = 157). The day 42 PCR adjusted per protocol adequate clinical and parasitological responses were 95% and 100% in the AL and DP groups respectively, Mantel-Haenszel weighted odds ratio (OR) 0.22 (95% CI 0–0.68), p = 0.022. In a modified intention to treat analysis in which treatment failures day 0 and reinfections were also considered as treatment failures adequate clinical and parasitological responses were 94% and 97% (OR 0.42 [95% CI, 0.13–1.38], p = 0.15). Parasite clearance and symptom resolution were similar with both treatments. Conclusions: Both treatments achieved the WHO recommended efficacy for antimalarials about to be adopted as policy. DP was not inferior to AL for treatment of uncomplicated P. falciparum malaria in Guinea-Bissau. Trial Registration: ClinicalTrials.gov [ABSTRACT FROM AUTHOR]

Background: Co-infection with human immunodeficiency virus (HIV) and hepatitis B virus (HBV) may lead to accelerated hepatic disease progression with higher rates of liver cirrhosis and liver-related mortality compared with HBV mono-infection. Co or super-infection with hepatitis Delta virus (HDV) may worsen the liver disease and complicate treatment possibilities. Methods: In this cross-sectional study we included HIV-infected individuals who had a routine blood analysis performed at an HIV clinic in Bissau, Guinea-Bissau between the 28th of April and 30th of September 2011. All patients were interviewed, had a clinical exam performed and had a blood sample stored. The patients' samples were tested for HBV and HDV serology, and HBV/HDV viral loads were analyzed using in-house real-time PCR methods. Results: In total, 576 patients (417 HIV-1, 104 HIV-2 and 55 HIV-1/2) were included in this study. Ninety-four (16.3%) patients were HBsAg positive of whom 16 (17.0%) were HBeAg positive. In multivariable logistic regression analysis, CD4 cell count <200 cells/ µl and animist religion were significantly associated with HBsAg positivity. Due to scarcity of available plasma, virological analyses were not performed for eight patients. HBV DNA was detected in 42 of 86 samples (48.8%) positive for HBsAg and genotyping was performed in 26 patients; 25 of whom had genotype E and one genotype D. Among 9 patients on antiretroviral treatment (ART), one patient had the [L180M, M204V] mutation associated with lamivudine resistance. Among the HBsAg positive patients 25.0% were also positive for anti-HDV and 4/9 (44.4%) had detectable HDV RNA. Conclusion: HBV and HDV were frequent co-infections among HIV positive patients in Guinea-Bissau and chronic infection was associated with severe immunosuppression. Lamivudine was widely used among HBsAg positive patients with the risk of developing resistant HBV. [ABSTRACT FROM AUTHOR]

Background: After measles vaccine (MV), all-cause mortality is reduced more than can be explained by the prevention of measles, especially in females. Objective: We aimed to study the biological mechanisms underlying the observed non-specific and sex-differential effects of MV on mortality. Methods: Within a large randomised trial of MV at 4.5 months of age blood samples were obtained before and six weeks after randomisation to early MV or no early MV. We measured concentrations of cytokines and soluble receptors from plasma (interleukin-1 receptor agonist (IL-1Ra), IL-6, IL-8, IL-10, tumor necrosis factor (TNF)-α, monocyte chemoattractant protein (MCP)-1, soluble urokinase-type plasminogen activator receptor), and secreted cytokines (interferon-γ, TNF-α, IL-5, IL-10, IL-13, IL-17) after in vitro challenge with innate agonists and recall antigens. We analysed the effect of MV in multiple imputation regression, overall and stratified by sex. The majority of the infants had previously been enrolled in a randomised trial of neonatal vitamin A. Post hoc we explored the potential effect modification by neonatal vitamin A. Results: Overall, MV versus no MV was associated with higher plasma MCP-1 levels, but the effect was only significant among females. Additionally, MV was associated with increased plasma IL-1Ra. MV had significantly positive effects on plasma IL-1Ra and IL-8 levels in females, but not in males. These effects were strongest in vitamin A supplemented infants. Vitamin A shifted the effect of MV in a pro-inflammatory direction. Conclusions: In this explorative study we found indications of sex-differential effects of MV on several of the plasma biomarkers investigated; in particular MV increased levels in females, most strongly in vitamin A recipients. The findings support that sex and micronutrient supplementation should be taken into account when analysing vaccine effects. Trial Registration: clinicaltrials.gov number NCT 00168545 [ABSTRACT FROM AUTHOR]

Background: The mechanisms behind heterologous immunity and non-specific effects of vaccines on mortality are not well understood. We examined associations between cytokine responses and subsequent mortality in low-birth-weight infants in Guinea-Bissau. Methods: A low-birth-weight trial randomized children to Bacille Calmette-Guérin (BCG) at birth or later according to local policy. Blood samples were obtained from a sub-group at age 6 weeks. Interleukin (IL)-5, IL-10, IL-13, interferon (IFN)-γ, and tumor necrosis factor (TNF)-α were measured in whole-blood cell cultures stimulated with lipopolysaccharide (LPS), phytohaemagglutinin (PHA), or purified protein derivative (PPD). The outcome was mortality between bleeding and 1 year of age. Non-linear associations between cytokine responses and mortality were examined. Results: Cytokine measurements were available from 390 children. The mortality rate (MR) was high (6.8/100 person-years-observation (PYO)). Both low and high cytokine responses to LPS and PHA were associated with high mortality (MR up to 25/100 PYO in the lowest 10% and 9.2/100 PYO in the highest 10%). In BCG-vaccinated children, higher IFN-γ responses to PPD were associated with better survival (MR ratio = 0.43 (0.24–0.77)). Conclusions: Data presented a rare opportunity to explore associations between cytokine responses and mortality. Both low and high cytokine responses were associated with high mortality; a balanced response to invading pathogens seems preferable. [ABSTRACT FROM AUTHOR]