Urban arbovirus exposure in blood donations from an endemic area of Brazil.

Background And Objectives: In Brazil, urban arboviruses, such as dengue virus (DENV), Zika virus (ZIKV) and chikungunya virus (CHIKV), constitute a major public health problem, and due to their endemicity and asymptomatic cases, they pose a potential threat to blood donations. Rio de Janeiro (RJ), Brazil, has been impacted by extensive DENV epidemics over the last 30 years and, after 2015, by CHIKV and ZIKV.

Materials And Methods: Urban arboviruses DENV, ZIKV and CHIKV were investigated in blood donations (n = 778) at the State Institute of Hematology, HEMORIO (RJ) from 2019 to 2022 by serological and molecular methods.

Antiviral and Virucidal Activities of (Cat's Claw) against the Chikungunya Virus.

(UT) is a medicinal plant popularly known as cat's claw belonging to the Rubiaceae family that has been reported to display antiviral and anti-inflammatory activities. The chikungunya virus (CHIKV) outbreaks constitute a Brazilian public health concern. CHIKV infection develops an abrupt onset of fever, usually accompanied by a skin rash, besides incapacitating polyarthralgia.

The Innate Immune Response in DENV- and CHIKV-Infected Placentas and the Consequences for the Fetuses: A Minireview.

Dengue virus (DENV) and chikungunya (CHIKV) are arthropod-borne viruses belonging to the and families, respectively. Infection by both viruses can lead to a mild indistinct fever or even lead to more severe forms of the diseases, which are characterized by a generalized inflammatory state and multiorgan involvement. Infected mothers are considered a high-risk group due to their immunosuppressed state and the possibility of vertical transmission.

Miconia albicans (Melastomataceae) to treat Chikungunya viral infection: An effectual symptom-driven ethnomedicinal repurposing of an anti-inflammatory species?

Ethnopharmacological Relevance: Miconia albicans (MA) is consumed all over the Brazilian territory as a remedy to treat rheumatoid arthritis and has been increasingly used to alleviate the deleterious symptoms caused by Chikungunya virus (CHIKV).

Aim Of The Study: To investigate the effect of MA leaf and stem hydroethanolic extracts (LE and SE, respectively), their fractions enriched in triterpene acids or polyphenols as well isolated constituents, on CHIKV hosted in Vero cells.

Materials And Methods: Polyphenol profiles of LE and SE were dereplicated by HPLC-DAD-ESI-MS/MS, aided by standards.

Increased Indoleamine 2,3-Dioxygenase 1 (IDO-1) Activity and Inflammatory Responses during Chikungunya Virus Infection.

Chikungunya virus (CHIKV) infection causes intense cytokine/chemokine inflammatory responses and debilitating joint pain. Indoleamine2,3-dioxygenase 1 (IDO-1) is an enzyme that initiates the tryptophan degradation that is important in initial host innate immune defense against infectious pathogens. Besides that, IDO-1 activation acts as a regulatory mechanism to prevent overactive host immune responses.

Serological Diagnosis of Dengue.

A reliable and specific diagnosis is imperative in viral diagnosis, both for clinical management and surveillance, and to ensure that early treatment and control measures are carried out. The number of days of illness is important to choose the most appropriate method to be used and for the correct interpretation of the results obtained. Specific IgM is elicited after that period, indicating an active infection and usually lasts up to 3 months.

Molecular Diagnosis of Dengue.

Several protocols for genomic amplification using reverse transcription followed by polymerase chain reaction (RT-PCR), important in the identification of the infecting serotype, have been used in the rapid diagnosis of Dengue Virus (DENV) infections. The qualitative protocol described by Lanciotti et al. (J Clin Microbiol 30: 545-551, 1992) suggested by WHO detects the four DENV serotypes simultaneously in one procedure "semi-nested," generating amplified products with specific sizes in base pairs for each serotype and it has been the most used in the past two decades.

Clinical, Virological, and Immunological Profiles of DENV, ZIKV, and/or CHIKV-Infected Brazilian Patients.

Background: Arboviruses co-circulating within a population that are transmitted by the same vector have the potential to cause coinfections. Coinfections with dengue virus (DENV), Zika virus (ZIKV), and chikungunya virus (CHIKV) have been occurring in Brazil, but it is not well-understood how human responses vary during mono- or coinfections and whether they play different roles in pathogenesis.

Methods: We investigated the clinical, virological, and immunological status during patients' acute infections, focusing on the CCL/CXC chemokines, proinflammatory, as well as anti-inflammatory cytokines levels quantified by ELISAs.

The inability of a dengue NS1 ELISA to detect Zika infections.

The presence of dengue virus (DENV), Zika virus (ZIKV) and Chikungunya virus (CHIKV) in Brazil, may result in a difficult diagnosis due to the signs and symptoms shared by those. Moreover, as DENV and ZIKV belong to the same family, serological assays may show a high rate of cross-reactivity. Here, we evaluated a Dengue NS1 capture assay for early and differential diagnosis of dengue during the Zika epidemic occurred in Brazil in 2016.

30 years of fatal dengue cases in Brazil: a review.

Background: Over the last 30 years, extensive dengue epidemics have occurred in Brazil, characterized by emergences and re-emergences of different serotypes, a change in the epidemiological profile and an increase in the number of severe and fatal cases. Here, we present a review on the dengue fatal cases that occurred in Brazil in 30 years (1986-2015).

Methods: We performed an ecological study by using secondary data on dengue fatal cases obtained in the National System of Reported Diseases (Sistema de Informação de Agravos de Notificação -SINAN) and in the Mortality Information System (SIM), both maintained by the Brazilian Ministry of Health.

Simultaneous circulation of arboviruses and other congenital infections in pregnant women in Rio de Janeiro, Brazil.

Background: Arboviruses (Zika, dengue and chikungunya) represent a major risk for pregnant women, especially because their vertical transmission can lead to neurological damage in newborns. Early diagnosis can be difficult due to similar clinical presentation with other congenital infections that are associated with congenital abnormalities.

Objectives: To investigate the circulation of arboviruses and other pathogens responsible for congenital infections, reporting clinical aspects and geographic distribution of maternal rash in a metropolitan region of Rio de Janeiro (Brazil).

First detection and molecular characterization of a DENV-1/DENV-4 co-infection during an epidemic in Rio de Janeiro, Brazil.

In the 80s, dengue viruses type 1 and 4 (DENV-1 and 4) were isolated in North region of Brazil. However, it was only after the DENV-1 introduction in the state of Rio de Janeiro (RJ) in mid-1980s, that dengue became a nationwide public health problem. In 2009, this serotype re-emerged causing an explosive epidemic in the country.

Following in the Footsteps of the Chikungunya Virus in Brazil: The First Autochthonous Cases in Amapá in 2014 and Its Emergence in Rio de Janeiro during 2016.

Currently, Brazil lives a triple arboviruses epidemic (DENV, ZIKV and CHIKV) making the differential diagnosis difficult for health professionals. Here, we aimed to investigate chikungunya cases and the possible occurrence of co-infections during the epidemic in Amapá (AP) that started in 2014 when the first autochthonous cases were reported and in Rio de Janeiro (RJ) in 2016. We further performed molecular characterization and genotyping of representative strains.

30 years of dengue fatal cases in Brazil: a laboratorial-based investigation of 1047 cases.

Background: Dengue viruses (DENV) have emerged and reemerged in Brazil in the past 30 years causing explosive epidemics. The disease may range from clinically asymptomatic infections to severe and fatal outcomes. We aimed to describe the epidemiological, clinical and laboratorial aspects of the dengue fatal cases received by a Regional Reference Laboratory, Brazil in 30 years.

NS1 Antigenemia and Viraemia Load: Potential Markers of Progression to Dengue Fatal Outcome?

Dengue is a worldwide problem characterized by a multifactorial pathogenesis. Considering the viral components, it is known that high viremia or high levels of the secreted nonstructural protein 1 (NS1) may be associated with a more severe disease. We aimed to characterize the NS1 antigenemia and viremia in dengue fatal and non-fatal cases, as potential markers of progression to a fatal outcome.

Clinical and Laboratory Profile of Zika and Dengue Infected Patients: Lessons Learned From the Co-circulation of Dengue, Zika and Chikungunya in Brazil.

Background: The current triple epidemic caused by dengue, zika and chikungunya constitutes a serious health problem in Brazil. The aim of this study was to investigate acute samples (up to the 7 days of symptoms) from patients presenting acute fever syndrome suspected as arboviral infection and characterize the clinical and laboratorial profile during the co-circulation of dengue, zika and chikungunya in Campo Grande, Mato Grosso do Sul (MS), midwest region of Brazil.

Methods: All suspected cases (n=134) were tested by using serological and molecular diagnostic tests including DENV, ZIKV and CHIKV RT-PCR, Dengue nonstructural protein 1 (NS1) antigen capture ELISA, anti- DENV IgM ELISA and anti-CHIKV IgM ELISA.

Evidence of dengue virus replication in a non-traumatic spleen rupture case.

The present report describes a case of splenic rupture due to dengue, a rare complication of dengue that should be considered in any patient with suspected dengue disease who started with left upper quadrant abdominal pain and hypotension. The pathophysiology of this entity is not yet well elucidated, but one of the theories present in the literature is that it is due to a depletion of coagulation factors and platelets leading to intra-splenic hemorrhage and rupture. The RT-PCR technique detected serotype 1 and histopathological studies of the spleen revealed significant atrophy of lymphoid follicles and extensive hemorrhage areas.

Dengue type 4 in Rio de Janeiro, Brazil: case characterization following its introduction in an endemic region.

Background: Due to the populations' susceptibility, DENV-4 introduction in 2010 led to the occurrence of explosive epidemics in the following years in Brazil. In 2011, DENV-4 was identified in Rio de Janeiro (RJ) and it was prevalent in 2012 and 2013. Here, we aimed to characterize clinical, epidemiological and laboratorial aspects of DENV-4 cases after this serotype introduction in an endemic scenario.

First Report of the East-Central South African Genotype of Chikungunya Virus in Rio de Janeiro, Brazil.

Background: Chikungunya virus (CHIKV) is an arbovirus that causes an acute febrile syndrome with a severe and debilitating arthralgia. In Brazil, the Asian and East-Central South African (ECSA) genotypes are circulating in the north and northeast of the country, respectively. In 2015, the first autochthonous cases in Rio de Janeiro, Brazil were reported but until now the circulating strains have not been characterized.

Dengue severity associated with age and a new lineage of dengue virus-type 2 during an outbreak in Rio De Janeiro, Brazil.

Dengue virus-type 2 (DENV-2) caused three outbreaks, in the years 1990, 1998, and 2008, in Rio de Janeiro, Brazil. The 2008 outbreak was the most severe in reported cases, hospitalizations, and deaths. To investigate virological and epidemiological factors that may have contributed to the pathogenic profile of 2008 epidemic, 102 patients sera obtained during the epidemic and inter-epidemic periods of three outbreaks were analysed by qRT-PCR to estimate viremia levels and their correlation with the clinical, immunological, and demographic patient characteristics.

Dengue epidemics in two distinct periods reveal distinct epidemiological, laboratorial and clinical aspects in a same scenario: analysis of the 2010 and 2013 epidemics in Mato Grosso do Sul, Brazil.

Background: Dengue is a major problem in Brazil. Epidemiological and clinical aspects were characterized in patients from two epidemics which occurred in Mato Grosso do Sul, Brazil.

Methods: Dengue cases were classified according to the 2009 WHO criteria, tested by serological and molecular biology tests and analysed for nonstructural protein 1 (NS1) antigenemia.