The organophosphate temephos has been the main insecticide used against larvae of the dengue and yellow fever mosquito (Aedes aegypti) in Brazil since the mid-1980s. Reports of resistance date back to 1995; however, no systematic reports of widespread temephos resistance have occurred to date. As resistance investigation is paramount for strategic decision-making by health officials, our objective here was to investigate the spatial and temporal spread of temephos resistance in Ae. aegypti in Brazil for the last 12 years using discriminating temephos concentrations and the bioassay protocols of the World Health Organization. The mortality results obtained were subjected to spatial analysis for distance interpolation using semi-variance models to generate maps that depict the spread of temephos resistance in Brazil since 1999. The problem has been expanding. Since 2002-2003, approximately half the country has exhibited mosquito populations resistant to temephos. The frequency of temephos resistance and, likely, control failures, which start when the insecticide mortality level drops below 80%, has increased even further since 2004. Few parts of Brazil are able to achieve the target 80% efficacy threshold by 2010/2011, resulting in a significant risk of control failure by temephos in most of the country. The widespread resistance to temephos in Brazilian Ae. aegypti populations greatly compromise effective mosquito control efforts using this insecticide and indicates the urgent need to identify alternative insecticides aided by the preventive elimination of potential mosquito breeding sites.
Introduction: COVID-19 emerged in late 2019 and quickly became a serious public health problem worldwide. This study aim to describe the epidemiological course of cases and deaths due to COVID-19 and their impact on hospital bed occupancy rates in the first 45 days of the epidemic in the state of Ceará, Northeastern Brazil. Methods: The study used an ecological design with data gathered from multiple government and health care sources. Data were analyzed using Epi Info software. Results: The first cases were confirmed on March 15, 2020. After 45 days, 37,268 cases reported in 85.9% of Ceará's municipalities, with 1,019 deaths. Laboratory test positivity reached 84.8% at the end of April, a period in which more than 700 daily tests were processed. The average age of cases was 67 (<1-101) years, most occurred in a hospital environment (91.9%), and 58% required hospitalization in an ICU bed. The average time between the onset of symptoms and death was 18 (1-56) days. Patients who died in the hospital had spent an average of six (0-40) days hospitalized. Across Ceará, the bed occupancy rate reached 71.3% in the wards and 80.5% in the ICU. Conclusions: The first 45 days of the COVID-19 epidemic in Ceará revealed a large number of cases and deaths, spreading initially among the population with a high socioeconomic status. Despite the efforts by the health services and social isolation measures the health system still collapsed.
. We describe six cases of healthcare professionals in Brazil who recovered but again presented symptoms consistent with COVID-19, with new positive reverse transcription (RT)-PCR test results. The cases reported herein presented symptom onset between March 16, 2020 and April 9, 2020. All were health professionals (four medical doctors), five were female, with a median age of 43.5 years, and three had comorbidities. All patients were confirmed for SARS-CoV-2 detection by RT-PCR in naso and/or oropharyngeal swab samples. Among the reported cases, three (50%) underwent RT-PCR testing in the period between the two symptomatic episodes, with negative results. The time elapsed between the onset of symptoms in the two episodes ranged from 53 to 70 days (median, 56.5 days). In the first episode, the main symptoms described were fever (4/6), myalgia (3/6), sore throat (3/6), and cough (3/6). Meanwhile, during the second episode, fever (4/6) and weakness (3/6) predominated. Most of the cases progressed without complications, although one individual presented hypoxemia (minimum SatO 2 of 90%) in both episodes, and two, only in the second, one of which required intensive care unit admission, progressing with improvement after medication and receiving noninvasive ventilatory support. We report cases with recurrence of symptoms compatible with COVID-19, with positive RT-PCR results, that could represent the occurrence of viral reactivation or reinfection. The true nature of this phenomenon should be better clarified in future studies.
In June 2019, a horse with neurological disorder was diagnosed with West Nile virus (WNV) in Boa Viagem, a municipality in the state of Ceará, northeast Brazil. A multi-institutional task force coordinated by the Brazilian Ministry of Health was deployed to the area for case investigation. A total of 513 biological samples from 78 humans, 157 domestic animals and 278 free-ranging wild birds, as well as 853 adult mosquitoes of 22 species were tested for WNV by highly specific serological and/or molecular tests. No active circulation of WNV was detected in vertebrates or mosquitoes by molecular methods. Previous exposure to WNV was confirmed by seroconversion in domestic birds and by the detection of specific neutralizing antibodies in 44% (11/25) of equids, 20.9% (14/67) of domestic birds, 4.7% (13/278) of free-ranging wild birds, 2.6% (2/78) of humans, and 1.5% (1/65) of small ruminants. Results indicate that not only equines but also humans and different species of domestic animals and wild birds were locally exposed to WNV. The detection of neutralizing antibodies for WNV in free-ranging individuals of abundant passerine species suggests that birds commonly found in the region may have been involved as amplifying hosts in local transmission cycles of WNV.
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