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The COVID-19 pandemic outbreak in late 2019 has had social, political, and economic consequences worldwide. However, its emergence was not a surprise. In 2015, a Panel organised by the World Health Organization highlighted the importance of learning about the crisis caused by the Ebola epidemic. In 1992, the Committee on Emerging Microbial Threats to Health of the US Institute of Medicine warned of the possibility of an emerging global microbial threat. In this text, we point out five arguments that reveal the global failure in facing the pandemic: (1) deficiency in the global alert system and the fragility of the International Health Regulations (IHR-2005), (2) problems of the international response to the pandemic, related to global health governance, (3) the dispersed global adoption of the elimination strategy (zero Covid) widely seen as a policy of restriction of freedom instead as a strategy of inequities reduction, (4) fragile control of the disease with a narrow reading of the associated problems, and (5) global setbacks in achieving the Sustainable Development Goals in the context of ongoing neoliberal national policies. Finally, we argue that overcoming the weaknesses discussed requires strengthening health systems in all their components and expanding social welfare policies.

Individuals with asymptomatic infection due to Plasmodium vivax are posited to be important reservoirs of malaria transmission in endemic regions. Here we studied a cohort of P. vivax malaria patients in a suburban area in the Brazilian Amazon. Overall 1,120 individuals were screened for P. vivax infection and 108 (9.6%) had parasitemia detected by qPCR but not by microscopy. Asymptomatic individuals had higher levels of antibodies against P. vivax and similar hematological and biochemical parameters compared to uninfected controls. Blood from asymptomatic individuals with very low parasitemia transmitted P. vivax to the main local vector, Nyssorhynchus darlingi. Lower mosquito infectivity rates were observed when blood from asymptomatic individuals was used in the membrane feeding assay. While blood from symptomatic patients infected 43.4% (199/458) of the mosquitoes, blood from asymptomatic infected 2.5% (43/1,719). However, several asymptomatic individuals maintained parasitemia for several weeks indicating their potential role as an infectious reservoir. These results suggest that asymptomatic individuals are an important source of malaria parasites and Science and Technology for Vaccines granted by Conselho Nacional de may contribute to the transmission of P. vivax in low-endemicity areas of malaria. Author summary Malaria still poses as one of the most important parasitic diseases in the world. The advance of molecular diagnosis brought to light the existence of asymptomatic infections, which may represent most of the infections in some areas. Importantly, the role of asymptomatic carriers in the natural history of malaria is not completely understood. Herein we describe the general characteristics of asymptomatic individuals infected with Plasmodium vivax, and provide evidence of their potential as parasitic reservoirs, even when molecular methods fail to detect the infection. Our findings reinforce the need for better diagnostic tests and open a new window of complexity to be considered in control programs.

Around 14% of world dengue virus (DENV) cases occur in the Americas, most of them in Brazil. While socioeconomic, environmental, and behavioral correlates have been analyzed thoroughly, the role played by population mobility on DENV epidemics, especially at the local level, remains scarce. This study assesses whether the daily pattern of population mobility is associated with DENV incidence in Campinas, a Brazilian major city with over 1.2 million inhabitants in São Paulo State. DENV notifications from 2007 to 2015 were geocoded at street level (n = 114,884) and combined with sociodemographic and environmental data from the 2010 population census. Population mobility was extracted from the Origin-Destination Survey (ODS), carried out in 2011, and daily precipitation was obtained from satellite imagery. Multivariate zero-inflated negative binomial regression models were applied. High population mobility presented a relevant positive effect on higher risk for DENV incidence. High income and residence in apartments were found to be protective characteristics against the disease, while unpaved streets, number of strategic points (such as scrapyards and tire repair shops), and precipitation were consistently risk factors.

This study aimed to assess agreement between antenatal estimates of gestational age by ultrasound and clinical records at birth in the Brazilian Amazon. Ultrasound examinations were scheduled during the second trimester for 578 pregnant women prospectively screened at primary health care units, following a standardized protocol for image quality control. A multistage algorithm was used to assess the best estimate of gestational age during the antenatal period, considering reliability of last menstrual period (LMP) and acceptable differences in relation to ultrasound estimates derived from fetal biparietal diameter and femur length. Agreement of antenatal estimates of gestational age confirmed by ultrasound and clinical records at birth was analyzed with Bland-Altman plots and kappa coefficients (preterm and postterm births). Overall, ultrasound examinations presented high quality (>90% of satisfactory images), and were adopted as the best estimate of gestational age among 83.4% of pregnant women, confirming reliable LMP in the remaining proportion. On average, difference in gestational age between antenatal estimates and clinical records was 0.43 week (95% CI: 0.32, 0.53). Classification of preterm births had a good agreement (kappa: 0.82, p11 years of education and cases of caesarean deliveries. In conclusion, high-quality ultrasound images from the second trimester of pregnancy based the assessment of gestational age, while reliability of LMP was limited. Information from clinical records at birth presented an acceptable agreement on average and for classification of preterm births, which is relevant for properly interpreting perinatal outcomes. Discrepancies in caesarean deliveries may warrant further investigation.

We investigated linear growth and weight attained among 772 children at 10-15 months of age in the first population-based birth cohort in the Brazilian Amazon. Sociodemographic, maternal and birth characteristics were collected in interviews soon after birth at baseline. Anthropometric evaluation was conducted at 10-15 months. Multiple linear regression models were fitted for length-for-age (LAZ) and body mass index (BMI)-for-age Z scores (BAZ), considering a hierarchical conceptual framework with determinants at distal, intermediate and proximal levels, with adjustment for the child's sex and age. Mean LAZ and BAZ were 0.31 (SD: 1.13) and 0.35 (SD: 1.06), respectively. Overall, 2.2% of children were stunted and 6.6% overweight. Among socioeconomic factors, household wealth index was positively associated with LAZ (p for trend = 0.01), while children whose families received assistance from the Bolsa Família conditional cash transfer program were 0.16 Z score thinner (95% CI: -0.31, -0.00). Maternal height and BMI were positively associated with both LAZ and BAZ at 10-15 months of age (p for trend

A transmissão de malária em projetos de assentamento na Amazônia, definida como malária de fronteira, é resultado de um intrincado processo envolvendo fatores biológicos, ecológicos, socioeconômicos e comportamentais, apresentando uma transição temporal de altas a baixas taxas ao longo de aproximadamente oito anos. Como resultado, um dos grandes desafios é a compreensão desse processo, através da identificação das variáveis determinantes da transmissão, considerando-se dimensões temporais e espaciais. Neste artigo é apresentada uma abordagem metodológica que caracteriza perfis de risco de malária em projetos de assentamento, a partir de uma análise multidisciplinar. Composta de três etapas, a abordagem combina análise espacial, geoestatística e modelos de Grade of Membership. Os resultados ressaltam a importância de medidas de controle diferenciadas de acordo com o estágio do projeto de assentamento (implementação recente ou antiga) e o nível de transmissão em cada localidade.La transmisión de malaria en proyectos de asentamiento en la Amazonia, definida como malaria de frontera, es el resultado de un intrincado proceso, involucrando factores biológicos, ecológicos, socioeconómicos y comportamentales, presentando una transición temporal de altas a bajas tasas a lo largo de aproximadamente ocho años. Como resultado, uno de los grandes desafíos es la comprensión de ese proceso, a través de la identificación de las variables determinantes de la transmisión, habiéndose considerado dimensiones temporales y espaciales. En este artículo es presentado un abordaje metodológico que caracteriza perfiles de riesgo de malaria en proyectos de asentamiento, a partir de un análisis multidisciplinario. Compuesto de tres etapas, el abordaje combina análisis espacial, geoestadística y modelos de Grade of Membership. Los resultados resaltan la importancia de medidas de control diferenciadas, de acuerdo a la etapa del proyecto de asentamiento (implementación reciente o antigua) y al nivel de transmisión en cada localidad.Malaria at colonization sites in the Brazilian Amazon is defined as frontier malaria, a complex phenomenon including biological, ecological, socioeconomic, and behavioral issues. It follows a specific temporal transition cycle lasting approximately eight years, oscillating from extremely high rates of transmission to lower and stable ones. A broader understanding of this phenomenon that would account for its spatial and temporal idiosyncrasies is a major challenge. In this article we present a methodological approach that describes malaria risk profiles based on a multidisciplinary analysis. The approach combines spatial analysis, geostatistical tools, and fuzzy-set models. Results highlight the need for spatially and temporally targeted interventions for mitigating the spread of this disease.

BackgroundAs a result of poor economic opportunities and an increasing shortage of affordable housing, much of the spatial growth in many of the world's fastest-growing cities is a result of the expansion of informal settlements where residents live without security of tenure and with limited access to basic infrastructure. Although inadequate water and sanitation facilities, crowding and other poor living conditions can have a significant impact on the spread of infectious diseases, analyses relating these diseases to ongoing global urbanization, especially at the neighborhood and household level in informal settlements, have been infrequent. To begin to address this deficiency, we analyzed urban environmental data and the burden of cholera in Dar es Salaam, Tanzania.Methodology/principal findingsCholera incidence was examined in relation to the percentage of a ward's residents who were informal, the percentage of a ward's informal residents without an improved water source, the percentage of a ward's informal residents without improved sanitation, distance to the nearest cholera treatment facility, population density, median asset index score in informal areas, and presence or absence of major roads. We found that cholera incidence was most closely associated with informal housing, population density, and the income level of informal residents. Using data available in this study, our model would suggest nearly a one percent increase in cholera incidence for every percentage point increase in informal residents, approximately a two percent increase in cholera incidence for every increase in population density of 1000 people per km(2) in Dar es Salaam in 2006, and close to a fifty percent decrease in cholera incidence in wards where informal residents had minimally improved income levels, as measured by ownership of a radio or CD player on average, in comparison to wards where informal residents did not own any items about which they were asked. In this study, the range of access to improved sanitation and improved water sources was quite narrow at the ward level, limiting our ability to discern relationships between these variables and cholera incidence. Analysis at the individual household level for these variables would be of interest.Conclusions/significanceOur results suggest that ongoing global urbanization coupled with urban poverty will be associated with increased risks for certain infectious diseases, such as cholera, underscoring the need for improved infrastructure and planning as the world's urban population continues to expand.

BackgroundMalaria control in Africa is most tractable in urban settlements yet most research has focused on rural settings. Elimination of malaria transmission from urban areas may require larval control strategies that complement adult mosquito control using insecticide-treated nets or houses, particularly where vectors feed outdoors.Methods and findingsMicrobial larvicide (Bacillus thuringiensis var. israelensis (Bti)) was applied weekly through programmatic, non-randomized community-based, but vertically managed, delivery systems in urban Dar es Salaam, Tanzania. Continuous, randomized cluster sampling of malaria infection prevalence and non-random programmatic surveillance of entomological inoculation rate (EIR) respectively constituted the primary and secondary outcomes surveyed within a population of approximately 612,000 residents in 15 fully urban wards covering 55 km(2). Bti application for one year in 3 of those wards (17 km(2) with 128,000 residents) reduced crude annual transmission estimates (Relative EIR [95% Confidence Interval] = 0.683 [0.491-0.952], P = 0.024) but program effectiveness peaked between July and September (Relative EIR [CI] = 0.354 [0.193 to 0.650], P = 0.001) when 45% (9/20) of directly observed transmission events occurred. Larviciding reduced malaria infection risk among children < or =5 years of age (OR [CI] = 0.284 [0.101 to 0.801], P = 0.017) and provided protection at least as good as personal use of an insecticide treated net (OR [CI] = 0.764 [0.614-0.951], P = 0.016).ConclusionsIn this context, larviciding reduced malaria prevalence and complemented existing protection provided by insecticide-treated nets. Larviciding may represent a useful option for integrated vector management in Africa, particularly in its rapidly growing urban centres.

RESUMO Objetivo: Analisar o desenvolvimento infantil em diferentes grupos sociais. Método: Estudo transversal com crianças menores de 3 anos cadastradas em unidades básicas de saúde de um município do estado de São Paulo, Brasil. O desenvolvimento infantil foi verificado com a Ficha de Acompanhamento do Desenvolvimento, do Ministério da Saúde. Utilizou-se do Índice de Reprodução Social para classificar famílias em grupos sociais e do modelo teórico hierárquico predefinido para análise de regressão logística univariada e múltipla. Resultados: A amostra foi composta por 348 crianças. 29% das crianças apresentavam ausência de algum marco do desenvolvimento esperado para a idade. No modelo final, grupo social e faixa etária associaram-se ao desenvolvimento infantil. Apresentaram maior chance de ausência de algum marco do desenvolvimento crianças dos grupos menos inseridos socialmente e com idade maior ou igual a 12 meses. Conclusão: A proporção de crianças com ausência de algum marco do desenvolvimento é elevada e associou-se à menor inserção social. Enfatiza-se a importância da vigilância do desenvolvimento pela equipe de Enfermagem da atenção primária para a identificação dos grupos mais vulneráveis e a intervenção precoce que minimize os efeitos negativos que se agravam com a idade.