Evidence in decision-making in the context of COVID-19 in Latin America.

Background: The pace of the COVID-19 pandemic poses an unprecedented challenge to the evidence-to-decision process. Latin American countries have responded to COVID-19 by introducing interventions to both mitigate the risk of infection and to treat cases. Understanding how evidence is used to inform government-level decision-making at a national scale is crucial for informing country and regional actors in ongoing response efforts.

Human Social Behavior and Demography Drive Patterns of Fine-Scale Dengue Transmission in Endemic Areas of Colombia.

Dengue is known to transmit between humans and A. aegypti mosquitoes living in neighboring houses. Although transmission is thought to be highly heterogeneous in both space and time, little is known about the patterns and drivers of transmission in groups of houses in endemic settings.

[Detection of dengue virus antigen in post-mortem tissues].

The epidemiological situation of dengue has worsened over the last decade. The difficulties in preventing its transmission and the absence of a vaccine or specific treatment have made dengue a serious risk to public health, health centers and research systems at different levels. Currently, most studies on the pathogenesis of dengue infection focus on the T-cell immune response almost exclusively in secondary infections and are aimed at identifying the mechanisms involved in the development of vascular permeability and bleeding events that accompany the infection.

The relevance of dengue virus genotypes surveillance at country level before vaccine approval.

Dengue is a major threat for public health in tropical and subtropical countries around the world. In the absence of a licensed vaccine and effective antiviral therapies, control measures have been based on education activities and vector elimination. Current efforts for developing a vaccine are both promising and troubling.

Development of a reverse transcription polymerase chain reaction method for yellow fever virus detection.

Introduction: Yellow fever is considered a re-emerging disease and is endemic in tropical regions of Africa and South America. At present, there are no standardized or commercialized kits available for yellow fever virus detection. Therefore, diagnosis must be made by time-consuming routine techniques, and sometimes, the virus or its proteins are not detected.

Advanced yellow fever virus genome detection in point-of-care facilities and reference laboratories.

Reported methods for the detection of the yellow fever viral genome are beset by limitations in sensitivity, specificity, strain detection spectra, and suitability to laboratories with simple infrastructure in areas of endemicity. We describe the development of two different approaches affording sensitive and specific detection of the yellow fever genome: a real-time reverse transcription-quantitative PCR (RT-qPCR) and an isothermal protocol employing the same primer-probe set but based on helicase-dependent amplification technology (RT-tHDA). Both assays were evaluated using yellow fever cell culture supernatants as well as spiked and clinical samples.

[Evaluation of the seroconversion as a response to rabies vaccination in dogs, Valle del Cauca, Colombia, 2009].

Introduction: The province of Valle del Cauca has been free of dog rabies for more than 20 years. However, sylvatic rabies foci remain which are threats to the health of the populace and its pets. Rabies vaccination campaigns are carried out annually in all 42 counties of the province.

[Morphological changes in lung tissue of victims associated with the 2009 A H1N1/v09 influenza pandemic in Colombia].

Introduction: Influenza is an acute respiratory infection that may be seasonal or pandemic. In 2009 The World Health Organization (WHO) declared an influenza pandemia; 3,876 cases and 239 deaths were reported in Colombia.

Objective: The morphological changes in lung tissues associated with virus infection H1N1/v09 were described from autopsied victims.

First international external quality assessment study on molecular and serological methods for yellow fever diagnosis.

Objective: We describe an external quality assurance (EQA) study designed to assess the efficiency and accurateness of molecular and serological methods used by expert laboratories performing YF diagnosis.

Study Design: For molecular diagnosis evaluation, a panel was prepared of 14 human plasma samples containing specific RNA of different YFV strains (YFV-17D, YFV South American strain [Brazil], YFV IvoryC1999 strain), and specificity samples containing other flaviviruses and negative controls. For the serological panel, 13 human plasma samples with anti-YFV-specific antibodies against different strains of YFV (YFV-17D strain, YFV IvoryC1999 strain, and YFV Brazilian strain), as well as specificity and negative controls, were included.

Phylogenetic reconstruction of dengue virus type 2 in Colombia.

Background: Dengue fever is perhaps the most important viral re-emergent disease especially in tropical and sub-tropical countries, affecting about 50 million people around the world yearly. In Colombia, dengue virus was first detected in 1971 and still remains as a major public health issue. Although four viral serotypes have been recurrently identified, dengue virus type 2 (DENV-2) has been involved in the most important outbreaks during the last 20 years, including 2010 when the fatality rate highly increased.

[Serological, molecular and virological analyses associated with yellow fever surveillance in Colombia].

Introduction: Yellow fever is an immunopreventable viral hemorrhagic fever that causes high morbidity and mortality in tropical and sub-tropical regions. In Colombia, approximately 5 million persons are at risk of becoming infected with yellow fever virus.

Objective: The serological, molecular and virological analyses on the yellow fever surveillance samples were summarized in order to indicate the importance of appropriate and timely sampling in the process of case confirmation.

Phylogenetic history demonstrates two different lineages of dengue type 1 virus in Colombia.

Background: Dengue Fever is one of the most important viral re-emergent diseases affecting about 50 million people around the world especially in tropical and sub-tropical countries. In Colombia, the virus was first detected in the earliest 70's when the disease became a major public health concern. Since then, all four serotypes of the virus have been reported.

Simultaneous circulation of genotypes I and III of dengue virus 3 in Colombia.

Background: Dengue is a major health problem in tropical and subtropical regions. In Colombia, dengue viruses (DENV) cause about 50,000 cases annually, 10% of which involve Dengue Haemorrhagic Fever/Dengue Shock Syndrome. The picture is similar in other surrounding countries in the Americas, with recent outbreaks of severe disease, mostly associated with DENV serotype 3, strains of the Indian genotype, introduced into the Americas in 1994.

[Detection of yellow fever virus by reverse transcriptase polymerase chain reaction in wild monkeys: a sensitive tool for epidemiologic surveillance].

Introduction: Yellow fever is a zoonotic infection maintained in nature by non-human primates. Appropriate surveillance with sensitive laboratory techniques is necessary to evidence viral activity in the tropical forest habitats of these primates.

Objective: Yellow fever virus was detected in hepatic tissue samples from non-human primates by reverse transcriptase polymerase chain reaction (RT-PCR) technique using specific primers for diagnosis.

[Molecular detection of yellow fever virus in human sera and mice brains].

A molecular method for the diagnosis of yellow fever virus infection was developed based on reverse transcription (RT) followed by polymerase chain reaction (PCR) amplification. Examinations were conducted on lyophilized sera from 3 fatal yellow fever cases and 4 fresh sera from 3 fatal cases and one from a symptomatic patient (positive IgM against yellow fever virus). Sera were extracted with TRIZOL-LS to isolate viral RNA for RT treatment and the PCR reaction included 2 primers sets designed specifically for yellow fever virus: sense, JM2104 (5'-CGTTGGGAGAGGAGATTC-3') y JM2249 (5'-TTCTTCACTTCGGTTGGG-3'), and antisense, JM2673 (5'-TCATCTGCCCTGCTTCTC-3') y JM2751 (5'-CCTCTCTGGTAAACATTCT-3').

Identification, cloning, and sequencing of different cytokine genes in four species of owl monkey.

Non-human primates could prove to be suitable models for the study of infectious diseases such as malaria, tuberculosis, and hepatitis; the molecules of their immune systems are in the process of being fully characterized. Due to the relevance of cytokines in the modulation of the immune response, a molecular analysis of these proteins in non-human primates from the Aotus genus was carried out. Peripheral blood mononuclear cells from four species of Aotusmonkey were obtained and their mRNAs for interleukin-2 (IL-2), IL-4, IL-6, IL-10, interferon-gamma (IFN), and tumor necrosis factor (TNF)-alpha were characterized.