Project description:Phylogenetic analysis of yellow fever virus (YFV) strains isolated from Venezuela strongly supports YFV maintenance in situ in Venezuela, with evidence of regionally independent evolution within the country. However, there is considerable YFV movement from Brazil to Venezuela and between Trinidad and Venezuela.
Project description:The recent reemergence of yellow fever virus (YFV) in Brazil has raised serious concerns due to the rapid dissemination of the virus in the southeastern region. To better understand YFV genetic diversity and dynamics during the recent outbreak in southeastern Brazil, we generated 18 complete and nearly complete genomes from the peak of the epidemic curve from nonhuman primates (NHPs) and human infected cases across the Espírito Santo and Rio de Janeiro states. Genomic sequencing of 18 YFV genomes revealed the estimated timing, source, and likely routes of yellow fever virus transmission and dispersion during one of the largest outbreaks ever registered in Brazil. We showed that during the recent epidemic, YFV was reintroduced from Minas Gerais to the Espírito Santo and Rio de Janeiro states multiple times between 2016 and 2019. The analysis of data from portable sequencing could identify the corridor of spread of YFV. These findings reinforce the idea that continued genomic surveillance strategies can provide information on virus genetic diversity and transmission dynamics that might assist in understanding arbovirus epidemics.IMPORTANCE Arbovirus infections in Brazil, including yellow fever, dengue, zika, and chikungunya, result in considerable morbidity and mortality and are pressing public health concerns. However, our understanding of these outbreaks is hampered by the limited availability of genomic data. In this study, we investigated the genetic diversity and spatial distribution of YFV during the current outbreak by analyzing genomic data from areas in southeastern Brazil not covered by other previous studies. To gain insights into the routes of YFV introduction and dispersion, we tracked the virus by sequencing YFV genomes sampled from nonhuman primates and infected patients from the southeastern region. Our study provides an understanding of how YFV initiates transmission in new Brazilian regions and illustrates that genomics in the field can augment traditional approaches to infectious disease surveillance and control.
Project description:The risk of the emergence and reemergence of zoonoses is high in regions that are under the strong influence of anthropogenic actions, as they contribute to the risk of vector disease transmission. Yellow fever (YF) is among the main pathogenic arboviral diseases in the world, and the Culicidae Aedes albopictus has been proposed as having the potential to transmit the yellow fever virus (YFV). This mosquito inhabits both urban and wild environments, and under experimental conditions, it has been shown to be susceptible to infection by YFV. In this study, the vector competence of the mosquito Ae. albopictus for the YFV was investigated. Female Ae. albopictus were exposed to non-human primates (NHP) of the genus Callithrix infected with YFV via a needle inoculation. Subsequently, on the 14th and 21st days post-infection, the legs, heads, thorax/abdomen and saliva of the arthropods were collected and analyzed by viral isolation and molecular analysis techniques to verify the infection, dissemination and transmission. The presence of YFV was detected in the saliva samples through viral isolation and in the head, thorax/abdomen and legs both by viral isolation and by molecular detection. The susceptibility of Ae. albopictus to YFV confers a potential risk of reemergence of urban YF in Brazil.
Project description:In this paper, we measure the effect of the 2020 COVID-19 pandemic wave at the national and subnational levels in selected Latin American countries that were most affected: Brazil, Chile, Ecuador, Guatemala, Mexico, and Peru. We used publicly available monthly mortality data to measure the impacts of the pandemic using excess mortality for each country and its regions. We compare the mortality, at national and regional levels, in 2020 to the mortality levels of recent trends and provide estimates of the impact of mortality on life expectancy at birth. Our findings indicate that from April 2020 on, mortality exceeded its usual monthly levels in multiple areas of each country. In Mexico and Peru, excess mortality was spreading through many areas by the end of the second half of 2020. To a lesser extent, we observed a similar pattern in Brazil, Chile, and Ecuador. We also found that as the pandemic progressed, excess mortality became more visible in areas with poorer socioeconomic and sanitary conditions. This excess mortality has reduced life expectancy across these countries by 2-10 years. Despite the lack of reliable information on COVID-19 mortality, excess mortality is a useful indicator for measuring the effects of the coronavirus pandemic, especially in the context of Latin American countries, where there is still a lack of good information on causes of death in their vital registration systems.Supplementary informationThe online version contains supplementary material available at 10.1186/s41118-021-00139-1.
Project description:Background and objectivesThe confinement by COVID-19 has affected the food chain and environments, which added to factors such as anxiety, frustration, fear and stress have modified the quality of the diet in the population around the world. The purpose of this study was to explore diet quality during the COVID-19 pandemic in 11 Latin American countries.MethodologyMulticentric, cross-sectional study. An online survey was applied to residents of 11 Latin-American countries, during April and May 2020, when confinement was mandatory. Diet quality was evaluated using a validated questionnaire.Result10,573 people participated in the study. The quality of the food by country shows that Colombia presented the best quality, while Chile and Paraguay presented the lowest. When comparing the overall results of diet quality by gender, schooling and age, women, people with more schooling and people under 30 years of age, presented better diet quality. The regression model showed that the variables associated with diet quality were: age (df = 3, F = 4. 57, p < 0.001), sex (df = 1, F = 131.01, p < 0.001), level of education (df = 1, F = 38.29, p < 0.001), perception of weight change (df = 2, F = 135.31, p < 0.001), basis services (df = 1, F = 8.63, p = 0.003), and quarantine (df = 1, F = 12.14, p = 0.001).ConclusionIt is necessary for governments to intervene to reverse these indicators, considering that inadequate feeding favors the appearance of no communicable diseases, which favor a higher risk of infection and worse prognosis with COVID-19.
Project description:BackgroundBy the end of 2021, the SARS-CoV-2 Variant of Concern (VOC) Delta was predominant in most of the world. At the end of November, the Omicron variant was first detected in South Africa. This variant was immediately classified as VOC, due to the explosive increase of cases in South Africa, and the great number of mutations exhibited by this new lineage. Since then, Omicron VOC displaced Delta one in almost every country. Venezuela implemented in May 2021 molecular testing of all the passengers arriving at Venezuelan airports.MethodsIn this study, we analyzed the presence of variants of SARS-CoV-2 in those positive samples, by sequencing a small fragment of the Spike genomic region.ResultsThe Omicron variant was found in passengers arriving to Venezuela from the beginning of December. Complete genome analysis confirmed the presence of the Omicron VOC. The detection of this VOC coincided with an unprecedented increase in the frequency of passengers with positive nucleic acid testing.ConclusionsGenomic surveillance of samples for international travelers returning to Venezuela allowed us to rapidly detect the introduction of the Omicron variant in the country.
Project description:Yellow Fever Virus (YFV) reemergence in Brazil was followed by human suffering and the loss of biodiversity of neotropical simians on the Atlantic coast. The underlying mechanisms were investigated with special focus on distinct landscape fragmentation thresholds in the affected municipalities. An ecological study in epidemiology is employed to assess the statistical relationship between events of YFV and forest fragmentation in municipal landscapes. Negative binomial regression model showed that highly fragmented forest cover was associated with an 85% increase of events of YFV in humans and simians (RR = 1.85, CI 95% = 1.24-2.75, p=0.003) adjusted by vaccine coverage, population size, and municipality area. Intermediate levels of forest cover combined with higher levels of forest edge densities contribute to the YFV dispersion and the exponential growth of YF cases. Strategies for forest conservation are necessary for the control and prevention of YF and other zoonotic diseases that can spillover from the fragmented forest remains to populated cities of the Brazilian Atlantic coast.
Project description:BackgroundThe 2017-2018 yellow fever virus (YFV) outbreak in southeastern Brazil marked a reemergence of YFV in urban states that had been YFV-free for nearly a century. Unlike earlier urban YFV transmission, this epidemic was driven by forest mosquitoes. The objective of this study was to evaluate environmental drivers of this outbreak.Methodology/principal findingsUsing surveillance data from the Brazilian Ministry of Health on human and non-human primate (NHP) cases of YFV, we traced the spatiotemporal progression of the outbreak. We then assessed the epidemic timing in relation to drought using a monthly Standardized Precipitation Evapotranspiration Index (SPEI) and evaluated demographic risk factors for rural or outdoor exposure amongst YFV cases. Finally, we developed a mechanistic framework to map the relationship between drought and YFV. Both human and NHP cases were first identified in a hot, dry, rural area in northern Minas Gerais before spreading southeast into the more cool, wet urban states. Outbreaks coincided with drought in all four southeastern states of Brazil and an extreme drought in Minas Gerais. Confirmed YFV cases had an increased odds of being male (OR 2.6; 95% CI 2.2-3.0), working age (OR: 1.8; 95% CI: 1.5-2.1), and reporting any recent travel (OR: 2.8; 95% CI: 2.3-3.3). Based on this data as well as mosquito and non-human primate biology, we created the "Mono-DrY" mechanistic framework showing how an unusual drought in this region could have amplified YFV transmission at the rural-urban interface and sparked the spread of this epidemic.Conclusions/significanceThe 2017-2018 YFV epidemic in Brazil originated in hot, dry rural areas of Minas Gerais before expanding south into urban centers. An unusually severe drought in this region may have created environmental pressures that sparked the reemergence of YFV in Brazil's southeastern cities.
Project description:BackgroundCOVID-19 reached Latin-American countries slightly later than European countries, around February/March, allowing some emergency preparedness response in countries characterized by low health system capacities and socioeconomic disparities.ObjectiveThis paper focuses on the first months of the pandemic in five Latin American countries: Brazil, Chile, Colombia, Ecuador and Peru. It analyses how the pre-pandemic context, and the government's responses to contain and mitigate the spread together with economic measures have affected the COVID-19 health outcomes.MethodsExtensive qualitative document analysis was conducted focused on publicly-available epidemiological data and federal and state/regional policy documents since the beginning of the pandemic.ResultsThe countries were quick to implement stringent COVID-19 measures and incrementally scaled up their health systems capacity, although tracing and tracking have been poor. All five countries have experienced a large number of cases and deaths due to COVID-19. The analysis on the excess deaths also shows that the impact in deaths is far higher than the official numbers reported to date for some countries.ConclusionDespite the introduction of stringent measures of containment and mitigation, and the scale up of health system capacities, pre-pandemic conditions that characterize these countries (high informal employment, and social inequalities) have undermined the effectiveness of the countries' responses to the pandemic. The economic support measures put in place were found to be too timid for some countries and introduced too late in most of them. Additionally, the lack of a comprehensive strategy for testing and tracking has also contributed to the failure to contain the spread of the virus.
Project description:The saturation of the domestic market is one of the factors which drive firms to expand their business to other markets. Franchising is one of the formats adopted by companies when establishing their internationalization strategy. Spain is a country where franchising is strongly consolidated. This degree of maturity means that many chains seek other countries in which to operate. This work's specific aims are, on the one hand, to offer a general view of the current situation of Spanish franchisors in Latin American countries and, on the other hand, to analyze which the socio-economic or external factors are that determine the presence of Spanish franchisors in this market. Canonical-correlation analysis is used to do so. The results show that Spanish franchisors focus on the market's potential and size, and the per capita income, while they do not take into account its unemployment level, the country risk or the competitiveness there. This work shows that there is a series of socio-economic factors which influence the final choice of the destination country. However, this decision is not solely based on this country's socio-economic aspects, but also on the structure of the franchising firm itself and on its export experience in other markets. This study therefore complements other research and helps franchisors in their difficult decision of choosing the destination for their internationalization.