Mortality and Case Fatality Due to Visceral Leishmaniasis in Brazil: A Nationwide Analysis of Epidemiology,Trends and Spatial Patterns

Background

Visceral leishmaniasis (VL) is a significant public health problem in Brazil and several regions of the world. This study investigated the magnitude, temporal trends and spatial distribution of mortality related to VL in Brazil.

Methods

We performed a study based on secondary data obtained from the Brazilian Mortality Information System. We included all deaths in Brazil from 2000 to 2011, in which VL was recorded as cause of death. We present epidemiological characteristics, trend analysis of mortality and case fatality rates by joinpoint regression models, and spatial analysis using municipalities as geographical units of analysis.

Results

In the study period, 12,491,280 deaths were recorded in Brazil. VL was mentioned in 3,322 (0.03%) deaths. Average annual age-adjusted mortality rate was 0.15 deaths per 100,000 inhabitants and case fatality rate 8.1%. Highest mortality rates were observed in males (0.19 deaths/100,000 inhabitants), <1 year-olds (1.03 deaths/100,000 inhabitants) and residents in Northeast region (0.30 deaths/100,000 inhabitants). Highest case fatality rates were observed in males (8.8%), ≥70 year-olds (43.8%) and residents in South region (17.7%). Mortality and case fatality rates showed a significant increase in Brazil over the period, with different patterns between regions: increasing mortality rates in the North (Annual Percent Change – APC: 9.4%; 95% confidence interval – CI: 5.3 to 13.6), and Southeast (APC: 8.1%; 95% CI: 2.6 to 13.9); and increasing case fatality rates in the Northeast (APC: 4.0%; 95% CI: 0.8 to 7.4). Spatial analysis identified a major cluster of high mortality encompassing a wide geographic range in North and Northeast Brazil.

Conclusions

Despite ongoing control strategies, mortality related to VL in Brazil is increasing. Mortality and case fatality vary considerably between regions, and surveillance and control measures should be prioritized in high-risk clusters. Early diagnosis and treatment are fundamental strategies for reducing case fatality of VL in Brazil.     

Leishmania-HIV Co-infection: Clinical Presentation and Outcomes in an Urban Area in Brazil

BackgroundVisceral leishmaniasis (VL) is an emerging condition affecting HIV-infected patients living in Latin America, particularly in Brazil. Leishmania-HIV coinfection represents a challenging diagnosis because the clinical picture of VL is similar to that of other disseminated opportunistic diseases. Additionally, coinfection is related to treatment failure, relapse and high mortality.ObjectiveTo assess the clinical-laboratory profile and outcomes of VL-HIV-coinfected patients using a group of non HIV-infected patients diagnosed with VL during the same period as a comparator.MethodsThe study was conducted at a reference center for infectious diseases in Brazil. All patients with suspected VL were evaluated in an ongoing cohort study. Confirmed cases were divided into two groups: with and without HIV coinfection. Patients were treated according to the current guidelines of the Ministry of Health of Brazil, which considers antimony as the first-choice therapy for non HIV-infected patients and recommends amphotericin B for HIV-infected patients. After treatment, all patients with CD4 counts below 350 cells/mm³ received secondary prophylaxis with amphotericin B.ResultsBetween 2011 and 2013, 168 patients with suspected VL were evaluated, of whom 90 were confirmed to have VL. In total, 51% were HIV coinfected patients (46 patients). HIV-infected patients had a lower rate of fever and splenomegaly compared with immunocompetent patients. The VL relapse rate in 6 months was 37% among HIV-infected patients, despite receiving secondary prophylaxis. The overall case-fatality rate was 6.6% (4 deaths in the HIV-infected group versus 2 deaths in the non HIV-infected group). The main risk factors for a poor outcome at 6 months after the end of treatment were HIV infection, bleeding and a previous VL episode.ConclusionAlthough VL mortality rates among HIV-infected individuals are close to those observed among immunocompetent patients treated with amphotericin B, HIV coinfection is related to a low clinical response and high relapse rates within 6 months.     

Risk factors for death in children with visceral leishmaniasis

Background

Despite the major public health importance of visceral leishmaniasis (VL) in Latin America, well-designed studies to inform diagnosis, treatment and control interventions are scarce. Few observational studies address prognostic assessment in patients with VL. This study aimed to identify risk factors for death in children aged less than 15 years admitted for VL treatment in a referral center in northeast Brazil.

Methodology/Principal Findings

In a retrospective cohort, we reviewed 546 records of patients younger than 15 years admitted with the diagnosis of VL at the Instituto de Medicina Integral Professor Fernando Figueira between May 1996 and June 2006. Age ranged from 4 months to 13.7 years, and 275 (50%) were male. There were 57 deaths, with a case-fatality rate of 10%. In multivariate logistic regression, the independent predictors of risk of dying from VL were (adjusted OR, 95% CI): mucosal bleeding (4.1, 1.3–13.4), jaundice (4.4, 1.7–11.2), dyspnea (2.8, 1.2–6.1), suspected or confirmed bacterial infections (2.7, 1.2–6.1), neutrophil count <500/mm³ (3.1, 1.4–6.9) and platelet count <50,000/mm³ (11.7, 5.4–25.1). A prognostic score was proposed and had satisfactory sensitivity (88.7%) and specificity (78.5%).

Conclusions/Significance

Prognostic and severity markers can be useful to inform clinical decisions such as whether a child with VL can be safely treated in the local healthcare facility or would potentially benefit from transfer to referral centers where advanced life support facilities are available. High risk patients may benefit from interventions such as early use of extended-spectrum antibiotics or transfusion of blood products. These baseline risk-based supportive interventions should be assessed in clinical trials.     

Functional unit influence on building life cycle assessment

Purpose

The building sector is one of the most relevant sectors in terms of environmental impact. Different functional units (FUs) can be used in life cycle assessment (LCA) studies for a variety of purposes. This paper aimed to present different FUs used in the LCA of buildings and evaluate the influence of FU choice and setting in comparative studies.

Methods

As an example, we compared the “cradle to grave” environmental performance of four typical Brazilian residential buildings with different construction typologies, i.e., multi-dwelling and single dwelling, each with high and basic standards. We chose three types of FU for comparison: a dwelling with defined lifetime and occupancy parameters, an area of 1 m² of dwelling over a year period, and the accommodation of an occupant person of the dwelling over a day.

Results and discussion

The FU choice was found to bias the results considerably. As expected, the largest global warming indicator (GWi) values per dwelling unit and occupant were identified for the high standard dwellings. However, when measured per square meter, lower standard dwellings presented the largest GWi values. This was caused by the greater concentration of people per square meter in smaller area dwellings, resulting in larger water and energy consumption per square meter. The sensitivity analysis of FU variables such as lifetime and occupancy showed the GWi contribution of the infrastructure more relevant compared with the operation in high and basic standard dwellings. The definition of lifetime and occupancy parameters is key to avoid bias and to reduce uncertainty of the results when performing a comparison of dwelling environmental performances.

Conclusions

This paper highlights the need for adequate choice and setting of FU to support intended decision-making in LCA studies of the building sector. The use of at least two FUs presented a broader picture of building performance, helping to guide effective environmental optimization efforts from different approaches and levels of analysis. Information regarding space, time, and service dimensions should be either included in the FU setting or provided in the building LCA study to allow adjustment of the results for subsequent comparison.

     

Relative Risk of Visceral Leishmaniasis in Brazil: A Spatial Analysis in Urban Area

Background

Visceral leishmaniasis (VL) is a vector-borne disease whose factors involved in transmission are poorly understood, especially in more urban and densely populated counties. In Brazil, the VL urbanization is a challenge for the control program. The goals were to identify the greater risk areas for human VL and the risk factors involved in transmission.

Methodology

This is an ecological study on the relative risk of human VL. Spatial units of analysis were the coverage areas of the Basic Health Units (146 small-areas) of Belo Horizonte, Minas Gerais State, Brazil. Human VL cases, from 2007 to 2009 (n = 412), were obtained in the Brazilian Reportable Disease Information System. Bayesian approach was used to model the relative risk of VL including potential risk factors involved in transmission (canine infection, socioeconomic and environmental features) and to identify the small-areas of greater risk to human VL.

Principal Findings

The relative risk of VL was shown to be correlated with income, education, and the number of infected dogs per inhabitants. The estimates of relative risk of VL were higher than 1.0 in 54% of the areas (79/146). The spatial modeling highlighted 14 areas with the highest relative risk of VL and 12 of them are concentrated in the northern region of the city.

Conclusions

The spatial analysis used in this study is useful for the identification of small-areas according to risk of human VL and presents operational applicability in control and surveillance program in an urban environment with an unequal spatial distribution of the disease. Thus the frequent monitoring of relative risk of human VL in small-areas is important to direct and prioritize the actions of the control program in urban environment, especially in big cities.     

Asymptomatic Leishmania infection in HIV-positive outpatients on antiretroviral therapy in Pernambuco,Brazil

BackgroundVisceral leishmaniasis (VL) in HIV-positive individuals is a global health problem. HIV-Leishmania coinfection worsens prognosis and mortality risk, and HIV-Leishmania coinfected individuals are more susceptible to VL relapses. Early initiation of antiretroviral therapy can protect against Leishmania infection in individuals living in VL-endemic areas, and regular use of antiretrovirals might prevent VL relapses in these individuals. We conducted a cross-sectional study in Petrolina, Brazil, an VL-endemic area, to estimate the prevalence of asymptomatic Leishmania cases among HIV-positive outpatients.MethodsWe invited any HIV-positive patients, aged ≥ 18-years-old, under antiretroviral therapy, and who were asymptomatic for VL. Patients were tested for Leishmania with enzyme-linked immunosorbent assays (ELISA)-rK39, immunochromatographic test (ICT)-rK39, direct agglutination test (DAT), latex agglutination test (KAtex), and conventional polymerase chain reaction (PCR). HIV-Leishmania coinfection was diagnosed when at least one VL test was positive.ResultsA total of 483 patients were included. The sample was predominantly composed of single, < 48-years-old, black/pardo, heterosexual males, with fewer than 8 years of schooling. The prevalence of asymptomatic HIV-Leishmania coinfection was 9.11% (44/483). HIV mono-infected and HIV-Leishmania coinfected groups differed statistically significantly in terms of race (p = 0.045), marital status (p = 0.030), and HIV viral load (p = 0.046). Black/pardo patients, married patients, and those with an HIV viral load up to 100,000 copies/ml presented higher odds for HIV-Leishmania coinfection.ConclusionsA considerable number of asymptomatic Leishmania cases were observed among HIV-positive individuals in a VL-endemic area. Given the potential impact on transmission and health costs, as well as the impact on these coinfected individuals, studies of asymptomatic Leishmania carriers can be useful for guiding public health policies in VL-endemic areas aiming to control and eliminate the disease.     

Chronic Arsenic Exposure and Risk of Post Kala-azar Dermal Leishmaniasis Development in India: A Retrospective Cohort Study

BackgroundVisceral leishmaniasis (VL), with the squeal of Post-kala-azar dermal leishmaniasis (PKDL), is a global threat for health. Studies have shown sodium stibogluconate (SSG) resistance in VL patients with chronic arsenic exposure. Here, we assessed the association between arsenic exposure and risk of developing PKDL in treated VL patients.MethodsIn this retrospective study, PKDL patients (n = 139), earlier treated with SSG or any other drug during VL, were selected from the study cohort. Trained physicians, unaware of arsenic exposure, interviewed them and collected relevant data in a questionnaire format. All probable water sources were identified around the patient’s house and water was collected for evaluation of arsenic concentration. A GIS-based village-level digital database of PKDL cases and arsenic concentration in groundwater was developed and individual point location of PKDL cases were overlaid on an integrated GIS map. We used multivariate logistic regression analysis to assess odds ratios (ORs) for association between arsenic exposure and PKDL development.ResultsOut of the 429 water samples tested, 403 had arsenic content of over 10 μg/L, with highest level of 432 μg/L among the seven study villages. Multivariate adjusted ORs for risk of PKDL development in comparison of arsenic concentrations of 10.1–200 μg/L and 200.1–432.0 μg/L were 1.85 (1.13–3.03) and 2.31 (1.39–3.8) respectively. Interestingly, similar results were found for daily dose of arsenic and total arsenic concentration in urine sample of the individual. The multivariate-adjusted OR for comparison of high baseline arsenic exposure to low baseline arsenic exposure of the individuals in the study cohort was 1.66 (95% CI 1.02–2.7; p = 0.04).ConclusionOur findings indicate the need to consider environmental factors, like long time arsenic exposure, as an additional influence on treated VL patients towards risk of PKDL development in Bihar.     

Arsenic Exposure and Outcomes of Antimonial Treatment in Visceral Leishmaniasis Patients in Bihar,India: A Retrospective Cohort Study

BackgroundIn the late twentieth century, emergence of high rates of treatment failure with antimonial compounds (SSG) for visceral leishmaniasis (VL) caused a public health crisis in Bihar, India. We hypothesize that exposure to arsenic through drinking contaminated groundwater may be associated with SSG treatment failure due to the development of antimony-resistant parasites.MethodsA retrospective cohort design was employed, as antimony treatment is no longer in routine use. The study was performed on patients treated with SSG between 2006 and 2010. Outcomes of treatment were assessed through a field questionnaire and treatment failure used as a proxy for parasite resistance. Arsenic exposure was quantified through analysis of 5 water samples from within and surrounding the patient’s home. A logistic regression model was used to evaluate the association between arsenic exposure and treatment failure. In a secondary analysis survival curves and Cox regression models were applied to assess the risk of mortality in VL patients exposed to arsenic.ResultsOne hundred and ten VL patients treated with SSG were analysed. The failure rate with SSG was 59%. Patients with high mean local arsenic level had a non-statistically significant higher risk of treatment failure (OR = 1.78, 95% CI: 0.7–4.6, p = 0.23) than patients using wells with arsenic concentration <10 μg/L. Twenty one patients died in our cohort, 16 directly as a result of VL. Arsenic levels ≥ 10 μg/L increased the risk of all-cause (HR 3.27; 95% CI: 1.4–8.1) and VL related (HR 2.65; 95% CI: 0.96–7.65) deaths. This was time dependent: 3 months post VL symptom development, elevated risks of all-cause mortality (HR 8.56; 95% CI: 2.5–29.1) and of VL related mortality (HR 9.27; 95% CI: 1.8–49.0) were detected.Discussion/ConclusionThis study indicates a trend towards increased treatment failure in arsenic exposed patients. The limitations of the retrospective study design may have masked a strong association between arsenic exposure and selection for antimonial resistance in the field. The unanticipated strong correlation between arsenic exposure and VL mortality warrants further investigation.     

Risk Factors for Death from Visceral Leishmaniasis in an Urban Area of Brazil

Background

Over the last three decades, the epidemiological profile of visceral leishmaniasis (VL) has changed with epidemics occurring in large urban centers of Brazil, an increase in HIV/AIDS co-infection, and a significant increase in mortality. The objective of this study was to identify the risk factors associated with death among adult patients with VL from an urban endemic area of Brazil.

Methodology

A prospective cohort study included 134 adult patients with VL admitted to the University Hospital of the Federal University of Mato Grosso do Sul between August 2011 and August 2013.

Principal Findings

Patients ranged from 18 to 93 years old, with a mean age of 43.6 (±15.7%). Of these patients, 36.6% were co-infected with HIV/AIDS, and the mortality rate was 21.6%. In a multivariate analysis, the risk factors associated with death were secondary bacterial infection (42.86, 5.05–363.85), relapse (12.17, 2.06–71.99), edema (7.74, 1.33–45.05) and HIV/AIDS co-infection (7.33, 1.22–43.98).

Conclusions/Significance

VL has a high mortality rate in adults from endemic urban areas, especially when coinciding with high rates of HIV/AIDS co-infection.     

Arrangement of functional units within the Rapana thomasiana hemocyanin subunit RtH2

For the determination of the number and linear sequential arrangement of functional units (FUs) within the polypeptide chain of the Rapana hemocyanin subunit RtH2, a panel of mono-, di-, tri- and penta-FU fragments was generated by limited proteolysis of the purified subunit with four different enzymes. The individual cleavage products were isolated, characterized by SDS-PAGE and N-terminally sequenced. Most of the information about the FU sequential arrangement within RtH2 was obtained after limited proteolysis of the subunit with plasmin. Overall correlation of the data revealed the sequential order of the eight FUs within the polypeptide chain of RtH2, termed RtH2-a to RtH2-h. The sites, most sensitive to proteolytic cleavage with plasmin, are located at the C-terminus, between the FUs ef, fg and gh. A second main cleavage site was observed between the FUs cd. Endoproteinase GluC hydrolyzes these sites, too, but produces exclusively a mixture of mono-, di- and tri-FU fragments. The most stable fragments, the trimer abc and the dimer gh, are found in all cleavage mixtures of RtH2 studied. RtH2-h is compared with the corresponding h-FUs of the gastropodan hemocyanins of Pila leopoldvillensis, Helix pomatia, Megathura crenulata and Haliotis tuberculata, and a remarkable similarity is observed between them: an increased M(r) of approximately 65000 instead of approximately 50000, estimated for an average FU, suggesting that the sequence of RtH2-h is elongated by about 95 amino acid residues at the C-terminal part of the molecule, as found for beta(c)-HpH, HtH1 and HtH2.     

Creation of pacemaker remote monitoring networks between hospital and pharmacies during Covid-19 outbreak

IntroductionRemote Monitoring (RM) of Cardiac Implantable Electronic Devices (CIEDs) is proven to be safe and efficient. It has been adopted in our center since years. At the time of the recent Covid-19 outbreak, we introduced and tested a collaborative organizational model, through a new RM device (Totem), creating a network with the surrounding territory and limiting CIED patients’ presence in hospital.MethodsWe involved 4 neighbor pharmacies where Totem devices were installed; we called and informed 64 patients with Totem compatible pacemaker (PM) about the possibility to perform their PM follow-up (FU) in-pharmacy; 58 gave their consent and their data were inserted into our RM database.ResultsDuring an 18-month FU period, a total of 70 RM transmissions have been received: one alert of high atrial burden triggering a pharmacological optimization, one alert of high ventricular impedance leading to a new ventricular lead implantation and four alerts of elective replacement indicator. Fulfilled questionnaires revealed complete patient satisfaction.ConclusionsA collaborative network between our hospital and the surrounding territory to perform RM FUs of CIEDs during Covid-19 pandemic was feasible, leading to patient compliance and satisfaction and revealing important technical and clinical alerts.     

Keyhole Limpet Hemocyanin Type 2 (KLH2): Detection and Immunolocalization of a Labile Functional Unit h

Keyhole limpet hemocyanin (KLH) is a mixture of two hemocyanin isoforms, termed KLH1 and KLH2. Within KLH1 eight oxygen-binding functional units (FUs), 1-a to 1-h, have been identified, in contrast to KLH2, which was previously thought to be organized in seven FUs (2-a to 2-g). By limited proteolysis of KLH2 subunits, isolation of the polypeptide fragments, and N-terminal sequencing, we have now identified an eighth FU of type h, with a molecular mass of 43 kDa. This is unusually small for a FU h from a gastropodan hemocyanin. It is also shown that KLH2 didecamers can be split into a stable and homogeneous population of decamers by dialysis against 50 mM Tris/HCl, pH 7.5, in the absence of divalent cations. Electron microscopic immunolocalization using a specific monoclonal antibody reveals that FU KLH2-h is located at the collar of the decamer.     

Passive case detection for canine visceral leishmaniasis control in urban Brazil: Determinants of population uptake

BackgroundIn Brazil, the transmission of Leishmania infantum in urban settings is closely related to infection among dogs, with occasional transmission to humans. Serological screening of dogs for Leishmania spp. infection on requests of their owners (passive case detection) represents a frequent, but little studied, practice within the scope of Brazilian public health. This study identified factors associated with canine visceral leishmaniasis (CVL) diagnosis-seeking behavior of dog owners in Rondonópolis (236,000 inhabitants), a municipality in Central-Western Brazil where VL is endemic. Also, we evaluated the profile of dog owners and their animals screened on free demand.Methodology/Principal findingsUsing mixed effects negative binomial regression, we modelled the number of dogs screened for Leishmania infection on free demand per neighborhood from 2011 to 2016 as a function of time-dependent predictors (current or recent canine seropositivity and human VL incidence), distance to the screening site, and demographic variables. We assessed potential delays in the effect of time-dependent predictors on the outcome. Among 12,536 dogs screened for Leishmania infection, 64.2% were tested during serosurveys and 35.8% were tested on free demand. Of these, 63.9% were positive. Uptake of screening under free demand was strongly associated with higher levels of canine seropositivity in the neighborhood (current or recent) and decreasing distance to the screening site. A subsample of dog owners (n = 93) who sought CVL screening between 2016 and 2017 were interviewed in more detail. Owners with better socioeconomic status and dogs with apparent CVL clinical manifestations prevailed among them.Conclusions/SignificanceTo support timely CVL management, passive case detection along with awareness activities aimed at dog owners should be encouraged in endemic areas. Screening sites should be prioritized in accessible zones, as well as in socio-economically disadvantage areas. In parallel, CVL active case detection should be continued as a surveillance tool to guide control actions.     

Nautilus pompilius hemocyanin: 9 A cryo-EM structure and molecular model reveal the subunit pathway and the interfaces between the 70 functional units

Hemocyanins are giant extracellular oxygen carriers in the hemolymph of many molluscs. Nautilus pompilius (Cephalopoda) hemocyanin is a cylindrical decamer of a 350 kDa polypeptide subunit that in turn is a “pearl-chain” of seven different functional units (FU-a to FU-g). Each globular FU has a binuclear copper centre that reversibly binds one O₂ molecule, and the 70-FU decamer is a highly allosteric protein. Its primary structure and an 11 Å cryo-electron microscopy (cryo-EM) structure have recently been determined, and the crystal structures of two related FU types are available in the databanks. However, in molluscan hemocyanin, the precise subunit pathway within the decamer, the inter-FU interfaces, and the allosteric unit are still obscure, but this knowledge is crucial to understand assembly and allosterism of these proteins. Here we present the cryo-EM structure of Nautilus hemocyanin at 9.1 Å resolution (FSC_1/2-bit criterion), and its molecular model obtained by rigid-body fitting of the individual FUs. In this model we identified the subunit dimer, the subunit pathway, and 15 types of inter-FU interface. Four interface types correspond to the association mode of the two protomers in the published Octopus FU-g crystal. Other interfaces explain previously described morphological structures such as the fenestrated wall (which shows D5 symmetry), the three horizontal wall tiers, the major and minor grooves, the anchor structure and the internal collar (which unexpectedly has C5 symmetry). Moreover, the potential calcium/magnesium and N-glycan binding sites have emerged. Many interfaces have amino acid constellations that might transfer allosteric interaction between FUs. From their topologies we propose that the prime allosteric unit is the oblique segment between major and minor groove, consisting of seven FUs from two different subunits. Thus, the 9 Å structure of Nautilus hemocyanin provides fundamentally new insight into the architecture and function of molluscan hemocyanins.     

Patterns and temporal trends in the incidence of childhood and adolescence cancer in Cyprus 1998–2017: A population-based study from the Cyprus Paediatric Oncology Registry

BackgroundDespite its rarity, cancer in children and adolescents (CAC) is a major health issue worldwide. The lack of appropriate cancer registries is an obstacle for defining its incidence and survival, and informing cancer control. As in Cyprus, CAC epidemiology has not previously been comprehensively examined, we determined incidence rates and temporal trends of cancer in the 0–19 age group during 1998–2017.MethodsWe established the population based Paediatric Oncology Registry of Cyprus (PORCY) for the period 1998–2017. World age standardised incidence rate per million children and adolescents per year (ASRW) were calculated and time trends were assessed using Joinpoint regression analysis. Comparisons were made with other countries using the International Incidence of Childhood Cancer, third volume.ResultsFor all cancers combined, for ages 0–19-years, ASRW was 203.54 (95% CI 189.49, 217.59) one of the highest rates globally. The most frequent CAC were leukaemias followed by lymphomas, specified epithelial neoplasms and central nervous system tumours, differing to what is described in most other countries. For all cancers, both combined and individual types, except thyroid carcinoma (where incidence was rising), no significant temporal variation was found.ConclusionsTo inform cancer control activities, we conducted the first ever population-based epidemiological study of childhood and adolescent cancer (0–19 years) in Cyprus. The striking findings indicate high overall incidence rates that are among the world’s highest, a higher frequency of lymphomas and thyroid cancer than brain tumours, and rising incidence for thyroid, but not for other, cancers. These novel findings, will help the formulation of hypotheses to provide explanation for the high rates for all CAC in Cyprus and may contribute to the global efforts for improving prevention of cancer in this age group.     

Mercury distribution in two commercial fish species (Pimelodus maculatus and Calophysus macropterus) - Case study of river Acre (Acre state,Brazilian Amazon)

Abstract

Total mercury (Hg) concentrations were assessed during July 2017 in two commercial fish species Pimelodus maculatus and Calophysus macropterus from two locations of Acre river (Acre State, Brazilian Amazon) - Iñapari (undeveloped areas) and Assis Brazil (urban areas). The current study aimed to assess: (i) Hg spatial variations; (ii) the assimilation efficiencies in different tissues and (iii) the ecological quality of these ecosystems based on tissue Hg concentrations. Both species showed significantly (p?<?.05) different Hg concentrations between tissues. Hg concentrations were significantly higher than those previously reported for these Amazon regions. Hg concentrations in Assis Brazil were significantly higher (p?<?.05) than in Iñapari, indicating an anthropogenic influence. Bioaccumulation factors indicated that kidney and liver are the main Hg retention tissues. Considering European and Brazilian mercury guidelines in foodstuff, Iñapari and Assis Brazil are “Unpolluted” during July 2017, although hepatic Hg concentrations in C. macropterus from Assis Brazil showed evidences of anthropogenic contamination.     

Remote Sensing and Geographic Information Systems and risk of American visceral leishmaniasis in Bahia, Brazil

The spatial distribution of American visceral leishmaniasis (VL) was studied within the context of the environmental characteristics of northwest Bahia State in Brazil during an epidemic year. Geographic Information Systems (GIS) and Remote Sensing (RS) were used to characterize the landscape epidemiology of VL in order to identify and map high risk areas and endemic zones in a northwestern Bahia study area. Normalized Difference Vegetation Index (NDVI) was shown to be one of the most important risk factors in the area of study. Low NDVI values were related to high numbers of sand flies and high numbers of human and canine VL positive cases. Caatinga vegetation type was the dominant vegetation type in the endemic area. The use of RS and GIS allowed the identification of classes of VL risk that may be useful information to guide control program interventions.     

Prevalence, features and risk factors for malaria co-infections amongst visceral leishmaniasis patients from Amudat Hospital, Uganda

Background and methodology

Due to geographic overlap of malaria and visceral leishmaniasis (VL), co-infections may exist but have been poorly investigated. To describe prevalence, features and risk factors for VL-malaria co-infections, a case-control analysis was conducted on data collected at Amudat Hospital, Uganda (2000–2006) by Médecins sans Frontières. Cases were identified as patients with laboratory-confirmed VL and malaria at hospital admission or during hospitalization; controls were VL patients with negative malaria smears. A logistic regression analysis was performed to study the association between patients'' characteristics and the occurrence of the co-infection.

Results

Of 2414 patients with confirmed VL, 450 (19%) were positively diagnosed with concomitant malaria. Most co-infected patients were males, residing in Kenya (69%). While young age was identified by multivariate analysis as a risk factor for concurrent VL and malaria, particularly the age groups 0–4 (odds ratio (OR): 2.44; 95% confidence interval (CI): 1.52–3.92) and 5–9 years (OR: 2.23, 95% CI: 1.45-3-45), mild (OR: 0.53; 95% CI: 0.32–0.88) and moderate (OR: 0.45; 95% CI: 0.27–0.77) anemia negatively correlated with the co-morbidity. VL patients harboring skin infections were nearly three times less likely to have the co-infection (OR: 0.35; 95% CI: 0.17–0.72), as highlighted by the multivariate model. Anorexia was slightly more frequent among co-infected patients (OR: 1.71; 95% CI: 0.96–3.03). The in-hospital case-fatality rate did not significantly differ between cases and controls, being 2.7% and 3.1% respectively (OR: 0.87; 95% CI: 0.46–1.63).

Conclusions

Concurrent malaria represents a common condition among young VL patients living in the Pokot region of Kenya and Uganda. Although these co-morbidities did not result in a poorer prognosis, possibly due to early detection of malaria, a positive trend towards more severe symptoms was identified, indicating that routine screening of VL patients living in malaria endemic-areas and close monitoring of co-infected patients should be implemented.