Frequency of pleural effusion in dengue patients by severity, age and imaging modality: a systematic review and meta-analysis.

Background: Identification of pleural effusion (PE) in dengue infection is an objective measure of plasma leakage and may predict disease progression. However, no studies have systematically assessed the frequency of PE in patients with dengue, and whether this differs across age and imaging modality.

Methods: We searched Pubmed, Embase Web of Science and Lilacs (period 1900-2021) for studies reporting on PE in dengue patients (hospitalized and outpatient).

Left ventricular function by strain in uncomplicated malaria: a prospective study from the Brazilian Amazon.

We hypothesized that adults with uncomplicated malaria have lower left ventricular contractile function compared to the general population and that this improves after antimalarial treatment. We examined uncomplicated malaria and the general population from the Western part of the Brazilian Amazon Basin. All persons underwent an echocardiographic examination and peripheral blood smears.

Potential role of transthoracic echocardiography for screening LV systolic dysfunction in patients with a history of dengue infection. A cross-sectional and cohort study and review of the literature.

Background: Dengue virus can affect the cardiovascular system and men may be at higher risk of severe complications than women. We hypothesized that clinical dengue virus (DENV) infection could induce myocardial alterations of the left ventricle (LV) and that these changes could be detected by transthoracic echocardiography.

Methodology/principal Findings: We examined individuals from Acre in the Amazon Basin of Brazil in 2020 as part of the Malaria Heart Study.

Is self-rated health associated with cardiovascular risk factors and disease in a low-income setting? A cross-sectional study from the Amazon Basin of Brazil.

Objective: Prior studies have suggested that self-rated health may be a useful indicator of cardiovascular disease. Consequently, we aimed to assess the relationship between self-rated health, cardiovascular risk factors and subclinical cardiac disease in the Amazon Basin.

Design: Cross-sectional study.

Prevalence and Dynamic Changes in Lung Ultrasound Findings among Adults with Uncomplicated Malaria and Controls in the Amazon Basin, Brazil.

Malaria patients are at risk of cardiopulmonary complications but diagnosis and management can be difficult in resource-limited settings. B-lines on lung ultrasound (LUS) mark changes in lung density; however, little is known about their role in malaria. We aimed to examine the prevalence of B-lines in adults with malaria at baseline and follow-up compared with controls in the Amazon Basin.

Prevalence of rheumatic heart disease in adults from the Brazilian Amazon Basin.

Background: Rheumatic heart disease (RHD) continues to be a burden in low- and middle-income countries and prevalence estimates are lacking from South America. We aimed to determine the prevalence of RHD in the Brazilian Amazon Basin.

Methods: We examined a random sample of adults (≥18 years) from the general population, who underwent echocardiographic image acquisition by a medical doctor.

Naturally acquired antibody response to a Plasmodium falciparum chimeric vaccine candidate GMZ2.6c and its components (MSP-3, GLURP, and Pfs48/45) in individuals living in Brazilian malaria-endemic areas.

Background: The GMZ2.6c malaria vaccine candidate is a multi-stage Plasmodium falciparum chimeric protein which contains a fragment of the sexual-stage Pfs48/45-6C protein genetically fused to GMZ2, a fusion protein of GLURP and MSP-3, that has been shown to be well tolerated, safe and immunogenic in clinical trials performed in a malaria-endemic area of Africa. However, there is no data available on the antigenicity or immunogenicity of GMZ2.

Frequency of Electrocardiographic Alterations and Pericardial Effusion in Patients With Uncomplicated Malaria.

Studies have proposed that malaria may lead to electrocardiographic (ECG) changes and pericardial inflammation. We aimed to investigate the frequency of ECG alterations, determined by ECG and Holter monitoring, and pericardial effusion in patients with malaria infection. We performed a prospective observational study of adult patients with uncomplicated malaria in Amazonas, Brazil.

Reference values for left ventricular dimensions, systolic and diastolic function: a study from the Amazon Basin of Brazil.

Country- and ethnicity-specific reference values for echocardiographic parameters are necessary for decision making. No prior studies have examined reference values in adults from the Amazon Basin of Brazil. We performed echocardiographic examinations in 290 healthy adults (mean age 37 ± 14 years, 40% male) from the Brazilian Amazon.

Tropical diseases and risk of hypertension in the Amazon Basin: a cross-sectional study.

Although infectious diseases have been associated with cardiovascular conditions, little is known about tropical disease burden and hypertension. We hypothesized that a history of tropical infections was associated with hypertension. We examined participants from outpatient clinics in the Amazon Basin who were interviewed about prior exposure to tropical diseases, including dengue, malaria hospitalization, and leishmaniasis.

Cardiopulmonary alterations by ultrasound in a patient with uncomplicated mixed malaria infection: a case report from the Amazon Basin.

Background: Information on cardiopulmonary complications in clinical malaria is sparse and diagnosis may be difficult in resource-limited areas due to lack of proper diagnostic tools and access to medical care. A case of pericardial effusion and pulmonary alterations assessed by ultrasound in a patient with uncomplicated mixed malaria infection is described.

Case Presentation: A previously healthy 23-year-old male from the Amazon Basin was diagnosed with mixed infection of Plasmodium vivax and Plasmodium falciparum by peripheral blood smear.

Levels of hepatitis B antibody titers are affected by age and doses gap time in children from a high endemic area of the western Amazon.

Background: Despite completion of the vaccine schedule for hepatitis B virus (HBV), children may display levels of HBV surface antibodies (anti-HBs) that are considered inadequate for sufficient protection (<10 IU/L).

Aims: Our aim was to investigate if age and gap time between HBV vaccine doses may negatively affect the levels of anti-HBs in children, and if these relationships are modified by sex.

Methods: In a high-endemic HBV region of the western Brazilian Amazon we enrolled children who had completed the HBV vaccine schedule.

Plasmodium vivax metacaspase 1 (PvMCA1) catalytic domain is conserved in field isolates from Brazilian Amazon.

In the present study, we investigated the genetic diversity of Plasmodium vivax metacaspase 1 (PvMCA1) catalytic domain in two municipalities of the main malaria hotspot in Brazil, i.e., the Juruá Valley, and observed complete sequence identity among all P.

Recombinant Plasmodium vivax circumsporozoite surface protein allelic variants: antibody recognition by individuals from three communities in the Brazilian Amazon.

Circumsporozoite protein (CSP) variants of P. vivax, besides having variations in the protein repetitive portion, can differ from each other in aspects such as geographical distribution, intensity of transmission, vectorial competence and immune response. Such aspects must be considered to P.

Plasmodium falciparum infection dysregulates placental autophagy.

Plasmodium (P.) falciparum malaria during pregnancy has been frequently associated with severe consequences such as maternal anemia, abortion, premature birth, and reduced birth weight. Placental damage promotes disruption of the local homeostasis; though, the mechanisms underlying these events are still to be elucidated.

Ethno-knowledge and attitudes regarding snakebites in the Alto Juruá region, Western Brazilian Amazonia.

Background: The Alto Juruá region, located in the extreme western part of the Brazilian Amazonia, possesses an indigenous and riverine population which is involved in agricultural and forest extraction activities, and is a region that stands out for its high incidence of snakebites.

Objectives: To assess the attitudes of the victims, the characteristics of the snakes and the circumstances of the snakebites which occurred in a region where human populations are highly exposed to snakes.

Methods: The study was conducted at the Regional Hospital of Juruá in the Municipality of Cruzeiro do Sul (Acre), which regularly attends victims of snakebites in the Alto Juruá region.

Antibody Responses Against TRAP Recombinant and Synthetic Antigens in Naturally Exposed Individuals From the Brazilian Amazon.

Thrombospondin-related adhesive protein (TRAP) is essential for sporozoite motility and the invasion of mosquitoes' salivary gland and vertebrate's hepatocyte and is, thus, considered a promising pre-erythrocytic vaccine candidate. Despite the existence of a few reports on naturally acquired immune response against TRAP (PvTRAP), it has never been explored so far in the Amazon region, so results are conflicting. Here, we characterized the (IgG and IgG subclass) antibody reactivity against recombinant PvTRAP in a cross-sectional study of 299 individuals exposed to malaria infection in three municipalities (Cruzeiro do Sul, Mâncio Lima and Guajará) from the Acre state of the Brazilian Amazon.

Plasmodium vivax ookinete surface protein (Pvs25) is highly conserved among field isolates from five different regions of the Brazilian Amazon.

The Plasmodium vivax Ookinete Surface Protein (Pvs25) is one of the leading malaria Transmission-Blocking Vaccine candidates based on its high immunogenicity in animal models, transmission-blocking activity of antibodies elicited in clinical trials and high conservation among P. vivax isolates from endemic areas. However, the polymorphism in gene encoding Pvs25 in endemic areas from South America has been poorly studied so far.

Analysis of the lymphocyte cell population during malaria caused by Plasmodium vivax and its correlation with parasitaemia and thrombocytopaenia.

Background: The mechanisms of activation and regulation of T lymphocytes and their cytokines in malaria caused by Plasmodium vivax are complex and poorly understood. Previous data suggest that T cells balance protective immune responses with immune mediated pathology in malaria. This study investigates the lymphocytic profile of patients infected with P.

Malaria during pregnancy and newborn outcome in an unstable transmission area in Brazil: A population-based record linkage study.

Background: Malaria in pregnancy (MiP) is one of the major causes of mortality and morbidity in tropical regions, causing maternal anemia, intrauterine growth retardation, preterm birth, and low birth weight (LBW). The integration of the information systems on pregnancy and malaria could prove to be a useful method of improved decision making for better maternal-child health.

Methods: A population-based observational study acquired information retrospectively from all live births that occurred between 2006 and 2014 in Cruzeiro do Sul (Acre, Brazil).

Polymorphisms in Plasmodium vivax Circumsporozoite Protein (CSP) Influence Parasite Burden and Cytokine Balance in a Pre-Amazon Endemic Area from Brazil.

Mechanisms involved in severe P. vivax malaria remain unclear. Parasite polymorphisms, parasite load and host cytokine profile may influence the course of infection.

Effectiveness of the Live Births Information System in the Far-Western Brazilian Amazon.

The Live Birth Information System (SINASC) was implemented in 1990 for the purpose of providing information about the live-birth characteristics for the establishment of specific health indicators. This work evaluates the information quality of SINASC in relation to its data completeness and coverage for five municipalities from the State of Acre from 2005 to 2010. Lack of information (not filled out or stated as "unknown") was estimated for each variable.