Human outbreaks of a novel reassortant Oropouche virus in the Brazilian Amazon region.

The Brazilian western Amazon is experiencing its largest laboratory-confirmed Oropouche virus (OROV) outbreak, with more than 6,300 reported cases between 2022 and 2024. Here, we sequenced and analyzed 382 OROV genomes from human samples collected in Amazonas, Acre, Rondônia, and Roraima states, between August 2022 and February 2024, to uncover the origin and genetic evolution of OROV in the current outbreak. Genomic analyses revealed that the upsurge of OROV cases in the Brazilian Amazon coincides with spread of a novel reassortant lineage containing the M segment of viruses detected in the eastern Amazon region (2009-2018) and the L and S segments of viruses detected in Peru, Colombia, and Ecuador (2008-2021). The novel reassortant likely emerged in the Amazonas state between 2010 and 2014 and spread through long-range dispersion events during the second half of the 2010s. Phylodynamics reconstructions showed that the current OROV spread was mainly driven by short-range (< 2 km) movements consistent with the flight range of vectors. Nevertheless, a substantial proportion (22%) of long-range (> 10 km) OROV migrations were also detected, consistent with viral dispersion by humans. Our data provides a view of the unprecedented spread and evolution of OROV in Brazilian western Amazon region.

Perspectives of healthcare professionals on training for quantitative G6PD testing during implementation of tafenoquine in Brazil (QualiTRuST Study).

Effective radical cure of Plasmodium vivax malaria is essential for malaria elimination in Brazil. P. vivax radical cure requires administration of a schizonticide, such as chloroquine, plus an 8-aminoquinoline. However, 8-aminoquinolines cause hemolysis in individuals with glucose-6-phosphate dehydrogenase (G6PD) deficiency, requiring prior screening to exclude those at risk. Brazil is pioneering the implementation of tafenoquine, a single-dose 8-aminoquinoline indicated for P. vivax patients with >70% of normal G6PD activity. Tafenoquine implementation in Manaus and Porto Velho, two municipalities located in the western Brazilian Amazon, included comprehensive training of healthcare professionals (HCPs) on point-of-care quantitative G6PD testing and a new treatment algorithm for P. vivax radical cure incorporating tafenoquine. Training was initially provided to higher-level facilities (phase one) and later adapted for primary care units (phase two). This study analyzed HCP experiences during training and implementation and identified barriers and facilitators. In-depth interviews and focus discussion groups were conducted 30 days after each training for a purposive random sample of 115 HCPs. Thematic analysis was employed using MAXQDA software, analyzing data through inductive and deductive coding. Analysis showed that following the initial training for higher-level facilities, some HCPs did not feel confident performing quantitative G6PD testing and prescribing the tafenoquine regimen. Modifications to the training in phase two resulted in an improvement in understanding the implementation process of the G6PD test and tafenoquine, as well as in the knowledge acquired by HCPs. Additionally, knowledge gaps were addressed through in situ training, peer communication via a messaging app, and educational materials. Training supported effective deployment of the new tools in Manaus and Porto Velho and increased awareness of the need for pharmacovigilance. A training approach for nationwide implementation of these tools was devised. Implementing quantitative G6PD testing and tafenoquine represents a significant shift in P. vivax malaria case management. Consistent engagement with HCPs is needed to overcome challenges in fully integrating these tools within the Brazilian health system.

Factors associated with extubation failure in an intensive care unit: a case-control study / Fatores associados à falha de extubação em unidade de terapia intensiva: estudo de caso-controle / Factores asociados al fracaso de la extubación en unidad de cuidados intensivos: estudio de caso y control

Abstract Objective: to investigate the factors associated with extubation failure of patients in the intensive care unit. Method: unpaired, longitudinal, retrospective and quantitative case-control with the participation of 480 patients through clinical parameters for ventilator weaning. Data were analyzed by: Fisher's exact test or the chi-square test; unpaired two-tailed Student's t test; and Mann-Whitney test. Significant P values lower than or equal to 0.05 were admitted. Results: of the patients, 415 (86.5%) were successful and 65 (13.5%) failed. Success group: the most negative fluid balance, APACHE II in 20 (14-25), weak cough in 58 (13.9%). Failure group: the most positive fluid balance, APACHE II in 23 (19-29), weak cough in 31 (47.7%), abundant amount of pulmonary secretions in 47.7%. Conclusion: positive fluid balance and the presence of inefficient cough or inability to clear the airway were predictors of extubation failure.

Resumo Objetivo: investigar os fatores associados à falha de extubação de pacientes na unidade de terapia intensiva. Método: caso-controle não pareado, longitudinal, retrospectivo e quantitativo com a participação de 480 pacientes por meio de parâmetros clínicos para desmame ventilatório. Dados analisados por: Teste Exato de Fisher ou o teste Qui-quadrado; teste t de Student bicaudal não pareado; e teste de Mann-Whitney. Admitiram-se significantes valores de P menores ou iguais a 0,05. Resultados: dos pacientes, 415 (86,5%) tiveram sucesso e 65 (13,5%) falharam. Grupo sucesso: balanço hídrico mais negativo, APACHE II em 20 (14-25), tosse fraca em 58 (13,9%). Grupo falha: balanço hídrico mais positivo, APACHE II em 23 (19-29), tosse fraca em 31 (47,7 %), quantidade abundante de secreção pulmonar em 47,7 %. Conclusão: o balanço hídrico positivo e a presença de tosse ineficiente ou incapacidade de higienizar a via aérea foram preditores de falhas de extubação.

Resumen Objetivo: investigar los factores asociados al fracaso de la extubación de pacientes en la unidad de cuidados intensivos. Método: caso y control no apareado, longitudinal, retrospectivo y cuantitativo con la participación de 480 pacientes mediante parámetros clínicos para el destete de la ventilación. Datos analizados por: Prueba Exacta de Fisher o prueba de Chi-cuadrado; prueba t de Student de dos colas para datos no apareados; y prueba de Mann-Whitney. Se admitieron valores de P significativos menores o iguales a 0,05. Resultados: de los pacientes, 415 (86,5%) tuvieron éxito y 65 (13,5%) fracasaron. Grupo de éxito: balance hídrico más negativo, APACHE II en 20 (14-25), tos débil en 58 (13,9%). Grupo de fracaso: balance de líquidos más positivo, APACHE II en 23 (19-29), tos débil en 31 (47,7%), abundante cantidad de secreciones pulmonares en 47,7%. Conclusión: el balance hídrico positivo y la presencia de tos ineficaz o incapacidad para higienizar la vía aérea fueron predictores de fracaso de la extubación.

Hybrid Immunity Results in Enhanced and More Sustained Antibody Responses after the Second Sinovac-CoronaVac Dose in a Brazilian Cohort: DETECTCoV-19 Cohort.

We measured anti-SARS-CoV-2 antibody responses before and after CoronaVac (inactivated) vaccination in a case-control study performed in CoronaVac-immunized individuals participating in a longitudinal prospective study of adults in Manaus (DETECTCoV-19). Antibody responses were measured by standard serological immunoassays. Peak anti-S-RBD and neutralizing RBD-ACE2 blocking antibody responses after two doses of CoronaVac vaccine were similar in vaccine breakthrough cases (n = 9) and matched controls (n = 45). Individuals with hybrid immunity resulting from prior SARS-CoV-2 infection followed by vaccination (n = 22) had elevated levels of anti-N, anti-S-RBD and RBD-ACE2 blocking antibodies after the second vaccine dose compared to infection-naïve individuals (n = 48). Post-vaccination SARS-CoV-2-specific antibody responses rapidly waned in infection-naïve individuals. Antibody responses wane after vaccination, making individuals susceptible to infection by SARS-CoV-2 variants. These findings support the need for booster doses after primary vaccination. Population antibody serosurveys provide critical information toward implementing optimal timing of booster doses.

Chemical Recycling of PET Using Catalysts from Layered Double Hydroxides: Effect of Synthesis Method and Mg-Fe Biocompatible Metals.

The chemical recycling of poly(ethylene terephthalate) (PET) residues was performed via glycolysis with ethylene glycol (EG) over Mg-Fe and Mg-Al oxide catalysts derived from layered double hydroxides. Catalysts prepared using the high supersaturation method (h.s.c.) presented a higher surface area and larger particles, but this represented less PET conversion than those prepared by the low supersaturation method (l.s.c.). This difference was attributed to the smaller mass transfer limitations inside the (l.s.c.) catalysts. An artificial neural network model well fitted the PET conversion and bis(2-hydroxyethyl) terephthalate (BHET) yield. The influence of Fe in place of Al resulted in a higher PET conversion of the Mg-Fe-h.s.c. catalyst (~95.8%) than of Mg-Al-h.s.c. (~63%). Mg-Fe catalysts could be reused four to five times with final conversions of up to 97% with reaction conditions of EG: PET = 5:1 and catalyst: PET = 0.5%. These results confirm the Mg-Fe oxides as a biocompatible novel catalyst for the chemical recycling of PET residues to obtain non-toxic BHET for further polymerization, and use in food and beverage packaging.

Acute Chagas disease associated with ingestion of contaminated food in Brazilian western Amazon.

OBJECTIVE: To describe clinical, epidemiological and management information on cases of acute Chagas disease (ACD) by oral transmission in the state of Amazonas in western Amazon. METHODS: Manual and electronic medical records of patients diagnosed with ACD at the Fundação de Medicina Tropical Doutor Heitor Vieira Dourado (FMT-HVD) were included. RESULTS: There were 147 cases of acute CD registered from 10 outbreaks that occurred in the state of Amazonas between 2004 and 2022. The transmission pathway was through oral route, with probable contaminated palm fruit juice (açaí and/or papatuá), and involved people from the same family, friends or neighbours. Of 147 identified cases, 87 (59%) were males; cases were aged 10 months to 82 years. The most common symptom was the febrile syndrome (123/147; 91.8%); cardiac alterations were present in 33/100 (33%), (2/147; 1.4%) had severe ACD with meningoencephalitis, and 12 (8.2%) were asymptomatic. Most cases were diagnosed through thick blood smear (132/147; 89.8%), a few (14/147; 9.5%) were diagnosed by serology and (1/147; 0.7%) by polymerase chain reaction (PCR) and blood culture. In all these outbreaks, 74.1% of the patients were analysed by PCR, and Trypanosoma cruzi TcIV was detected in all of them. No deaths were recorded. The incidence of these foci coincided with the fruit harvest period in the state of Amazonas. CONCLUSION: The occurrence of ACD outbreaks in the Amazon affected individuals of both sexes, young adults, living in rural and peri-urban areas and related to the consumption of regional foods. Early diagnosis is an important factor in surveillance. There was a low frequency of cardiac alterations. Continuous follow-up of most patients was not carried out due to difficulty in getting to specialised centres; therefore, little is known about post-treatment.

Factors associated with extubation failure in an intensive care unit: a case-control study.

OBJECTIVE: to investigate the factors associated with extubation failure of patients in the intensive care unit. METHOD: unpaired, longitudinal, retrospective and quantitative case-control with the participation of 480 patients through clinical parameters for ventilator weaning. Data were analyzed by: Fisher's exact test or the chi-square test; unpaired two-tailed Student's t test; and Mann-Whitney test. Significant P values lower than or equal to 0.05 were admitted. RESULTS: of the patients, 415 (86.5%) were successful and 65 (13.5%) failed. Success group: the most negative fluid balance, APACHE II in 20 (14-25), weak cough in 58 (13.9%). Failure group: the most positive fluid balance, APACHE II in 23 (19-29), weak cough in 31 (47.7%), abundant amount of pulmonary secretions in 47.7%. CONCLUSION: positive fluid balance and the presence of inefficient cough or inability to clear the airway were predictors of extubation failure.

Multiple introductions and country-wide spread of DENV-2 genotype II (Cosmopolitan) in Brazil.

Dengue virus serotype 2, genotype Cosmopolitan (DENV-2-GII), is one of the most widespread DENV strains globally. In the USA, DENV-2 epidemics have been dominated by DENV-2 genotype Asian-American (DENV-2-GIII), and the first cases of DENV-2-GII were only described in 2019, in Peru, and in 2021 in Brazil. To gain new information about the circulation of DENV-2-GII in Brazil, we sequenced 237 DENV-2 confirmed cases sampled between March 2021 and March 2023 and revealed that DENV-2-GII is already present in all geographic regions of Brazil. The phylogeographic analysis inferred that DENV-2-GII was introduced at least four times in Brazil, between May 2020 and August 2022, generating multiple clades that spread throughout the country with different success. Despite multiple introductions of DENV-2-GII, analysis of the country-wide laboratory surveillance data showed that the Brazilian dengue epidemic in 2022 was dominated by DENV-1 in most states. We hypothesize that massive circulation of DENV-2-GIII in previous years in Brazil might have created a population immune barrier against symptomatic homotypic reinfections by DENV-2-GII, leading to sustained cryptic circulation in asymptomatic cases and localized outbreaks of this new genotype. In summary, our study stresses the importance of arboviral genomic surveillance to close monitoring and better understanding the potential impact of DENV-2-GII in the coming years.

Quantitative G6PD Deficiency Screening in Routine Malaria Diagnostic Units in the Brazilian Amazon (SAFEPRIM): An Operational Mixed-Methods Study.

BACKGROUND: Glucose-6-phosphate dehydrogenase (G6PD) deficiency testing is not routinely performed before primaquine treatment in most Plasmodium vivax endemic areas, despite the risk of primaquine-associated hemolysis. This is due to the operational challenges associated with pragmatic G6PD testing and as such needs to be addressed. METHODS AND FINDINGS: This mixed-methods operational study was aimed at implementing the quantitative point-of-care StandardTM G6PD (SD Biosensor, Korea) screening test in malaria treatment units (MTUs) in the municipalities of Rio Preto da Eva and Mâncio Lima, in the Brazilian Amazon, between mid-January 2020 and December 2020. In total, 1286 P. vivax cases were treated based on the Standard G6PD test: 1230 had activity equal to or greater than 4.0 U/g Hb, and 56 less than 4.0 U/g Hb. No G6PD deficient (G6PDd) genotypes were found in 96 samples from the 1230, and only 21 of the 56 G6PDd cases had confirmed G6PDd genotypes. Evaluations were conducted on the proficiency of health care professionals (HCPs) training to perform the test, the reliability of testing performed in the field, and the perceptions of HCPs and patients about the implementation. Post-training proficiency was 73.4% after a 4-hour training session. This study revealed that locations with lower malaria caseloads will need regular refresher training. The test was well accepted by both HCPs and patients. Signs and symptoms of hemolysis were not always associated with malaria treatment drugs by HCPs and patients. INTERPRETATION: Point-of-care quantitative G6PD testing can be performed at MTUs in the Brazilian Amazon to inform treatment decisions with primaquine. Limitations related to technical and cultural aspects need to be addressed further when expanding screening to larger areas.

Acute micro-outbreak of Chagas disease in the southeastern Amazon: a report of five cases.

BACKGROUND: Chagas disease is gaining importance in the Brazilian Amazon region as a differential diagnosis of febrile syndrome. The most recent microoutbreak occurred in Ipixuna, in Amazonas state. METHODS: An epidemiological survey was conducted using parasitological and serological tests, and electrocardiographic analysis. RESULTS: The patients belonged to one family and had ingested açaí acquired from Ipixuna. All patients reported fever and initially a thick blood smear test was done to identify Trypanosoma cruzi. Benznidazole treatment was administered to all patients. CONCLUSIONS: Knowledge of the epidemiological dynamics of Chagas disease allows us to improve control and management measures for this disease.