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In 2009, Cabo Verde diagnosed the first dengue cases, with 21,137 cases reported and Aedes aegypti was identified as the vector. Since the outbreak, chemical insecticides and source reduction were used to control the mosquito population. This study aimed to assess the susceptibility of A. aegypti populations from Santiago, Cabo Verde to insecticides and identify the mechanisms of resistance. Samples of A. aegypti eggs were obtained at two different time periods (2012 and 2014), using ovitraps in different locations in Santiago Island to establish the parental population. F 1 larvae were exposed to different concentrations of insecticides ( Bacillus thuringiensis var israelensis (Bti), diflubenzuron and temephos) to estimate the lethal concentrations (LC 90 ) and calculate the respective rate of resistance (RR 90 ). Semi-field tests using temephos-ABATE ® were performed to evaluate the persistence of the product. Bottle tests using female mosquitoes were carried out to determine the susceptibility to the adulticides malathion, cypermethrin and deltamethrin. Biochemical and molecular tests were performed to investigate the presence of metabolic resistance mechanisms, associated with the enzymes glutathione S-transferases (GSTs), esterases and mixed-function oxidases (MFO) and to detect mutations or alterations in the sodium channel and acetylcholinesterase genes. A. aegypti mosquitoes from Santiago exhibited resistance to deltamethrin, cypermethrin (mortality < 80%) and temephos (RR 90 = 4.4) but susceptibility to malathion (mortality ≥ 98%), Bti and diflubenzuron. The low level of resistance to temephos did not affect the effectiveness of Abate ® . The enzymatic analysis conducted in 2012 revealed slight changes in the activities of GST (25%), MFO (18%), α-esterase (19%) and β-esterase (17%), but no significant changes in 2014. Target site resistance mutations were not detected. Our results suggest that the A. aegypti population from Santiago is resistant to two major insecticides used for vector control, deltamethrin and temephos. To our knowledge, this is the first report of temephos resistance in an African A. aegypti population. The low level of temephos resistance was maintained from 2012–2014, which suggested the imposition of selective pressure, although it was not possible to identify the resistance mechanisms involved. These data show that the potential failures in the local mosquito control program are not associated with insecticide resistance. [ABSTRACT FROM AUTHOR]

Summary: Objectives: To assess the influence of acetyl-salicylic acid (ASA) on clinical outcomes in Staphylococcus aureus infective endocarditis (SA-IE). Methods: The International Collaboration on Endocarditis – Prospective Cohort Study database was used in this observational study. Multivariable analysis of the SA-IE cohort compared outcomes in patients with and without ASA use, adjusting for other predictive variables, including: age, diabetes, hemodialysis, cancer, pacemaker, intracardiac defibrillator and methicillin resistance. Results: Data were analysed from 670 patients, 132 of whom were taking ASA at the time of SA-IE diagnosis. On multivariable analysis, ASA usage was associated with a significantly decreased overall rate of acute valve replacement surgery (OR 0.58 [95% CI 0.35–0.97]; p <0.04), particularly where valvular regurgitation, congestive heart failure or periannular abscess was the indication for such surgery (OR 0.46 [0.25–0.86]; p <0.02). There was no reduction in the overall rates of clinically apparent embolism with prior ASA usage, and no increase in hemorrhagic strokes in ASA-treated patients. Conclusions: In this multinational prospective observational cohort, recent ASA usage was associated with a reduced occurrence of acute valve replacement surgery in SA-IE patients. Future investigations should focus on ASA''s prophylactic and therapeutic use in high-risk and newly diagnosed patients with SA bacteremia and SA-IE, respectively. [Copyright &y& Elsevier]

Zika virus (ZIKV) is a negative sense RNA virus from the Flaviviridae family, which was relatively unknown until the first human epidemic in Micronesia, in 2007. Since then, it spread to French Polynesia and the Americas. Recife, the capital of Pernambuco state and epicenter of the Zika epidemic in Brazil, experienced a large number of microcephaly cases and other congenital abnormalities associated to the ZIKV infection from, 2015 to 16. Evidences suggest that both Aedes aegypti and Culex quinquefasciatus mosquitoes from Recife are capable of replicating and transmitting the virus. Here, we conducted high throughput sequencing of ZIKV genomes directly from Ae. aegypti and Cx. quinquefasciatus mosquitoes collected during the ZIKV epidemics in Recife, in order to investigate the variability and evolution of the virus. We obtained 11 draft ZIKV genomes derived from 5 pools from each Ae. aegypti and Cx. quinquefasciatus species. Genome coverage breadth ranged from 16 to 100% and average depth from 45 to 46,584×. Two of these genomes were obtained from pools of Cx. quinquefasciatus females with no sign of blood in the abdomen. Amino acid substitutions found here were not species-specific. In addition, molecular clock dating estimated that ZIKV draft genomes obtained here were co-circulating in other regions of the country during the epidemics. Overall results highlight that viral mutations and even minor variants can be detected in genomes directly sequenced from mosquito samples and insights about natural viral genomic variability and viral evolution can be useful when designing tools for mosquito control programs. • Zika virus was detected in Aedes aegypti and Culex quinquefasciatus field collected samples; • Eleven complete Zika virus genomes were obtained from these samples; • The detection of the Zika virus in male samples confirms vertical transmission in Ae. aegypti and Cu. quinquefasciatus species. • These genomes belongs to two different Zika lineages that simultaneously cocirculated at the time of the epidemics; • Amino acid changes found were likely not involved in virus adaptation to different vectors species. [ABSTRACT FROM AUTHOR]

• Cats with street access are 2.54 times more likely to have sporotrichosis. • In sporotrichosis, avoiding street access is more important than just neutering cats. • Euthanasia and death are the most common outcome of sporotrichosis infected cats. • There is no relation between spatial distribution of animal sporotrichosis and HVI. An epidemiological characterization of animal sporotrichosis was carried out between 2017 and 2018, in a highly urbanized area in Brazil, including outcomes and the spatial distribution of the cases according to the health vulnerability index (HVI) of the study territory. One hundred and sixty-five cats and four dogs suspected of sporotrichosis were identified by a surveillance and control program previously implemented in the study area. One hundred and five of these animals (62.1 %) were considered positive for Sporothrix spp., of which 103 were cats and two were dogs. Cases predominated among male cats (53.4 %), although gender did not present a statistically significant association (p > 0.05) with sporotrichosis cases. Considering the positive cats, 55.4 % were not neutered and free access to the street was reported as a habit for 86.4 % of them. Roaming free in the streets increased the chance of infection by 2.54 times. We observed a high frequency of euthanasia or death (48.8 %) among 86 infected cats available to be included in the follow-up stage of the study, even when they were treated (46.5 %) and a low cure rate (31 %). The disease spread, unrelated to the HVI in the territory. Data produced suggested that avoiding access to the street seems to have greater importance to sporotrichosis control in cats than neutering and reinforces the importance of health education, especially in relation to responsible feline ownership. The free offer of diagnosis and treatment also should be taken into consideration as important measures to control the disease. [ABSTRACT FROM AUTHOR]

We aimed to investigate the real-life performance of the rapid antigen test in the context of a primary healthcare setting, including symptomatic and asymptomatic individuals that sought diagnosis during an Omicron infection wave. We prospectively accessed the performance of the DPP SARS-CoV-2 Antigen test in the context of an Omicron-dominant real-life setting. We evaluated 347 unselected individuals (all-comers) from a public testing centre in Brazil, performing the rapid antigen test diagnosis at point-of-care with fresh samples. The combinatory result from two distinct real-time quantitative PCR (RT-qPCR) methods was employed as a reference and 13 samples with discordant PCR results were excluded. The assessment of the rapid test in 67 PCR-positive and 265 negative samples revealed an overall sensitivity of 80.5% (CI 95% = 69.1%–89.2%), specificity of 99.2% (CI 95% = 97.3%–99.1%) and positive/negative predictive values higher than 95%. However, we observed that the sensitivity was dependent on the viral load (sensitivity in Ct < 31 = 93.7%, CI = 82.8%–98.7%; Ct > 31 = 47.4%, CI = 24.4%–71.1%). The positive samples evaluated in the study were Omicron (BA.1/BA.1.1) by whole-genome sequencing (n = 40) and multiplex RT-qPCR (n = 17). Altogether, the data obtained from a real-life prospective cohort supports that the rapid antigen test sensitivity for Omicron remains high and underscores the reliability of the test for COVID-19 diagnosis in settings with high disease prevalence and limited PCR testing capability. [Display omitted] [ABSTRACT FROM AUTHOR]

The global spread of new SARS-CoV-2 variants of concern underscore an urgent need of simple deployed molecular tools that can differentiate these lineages. Several tools and protocols have been shared since the beginning of the COVID-19 pandemic, but they need to be timely adapted to cope with SARS-CoV-2 evolution. Although whole-genome sequencing (WGS) of the virus genetic material has been widely used, it still presents practical difficulties such as high cost, shortage of available reagents in the global market, need of a specialized laboratorial infrastructure and well-trained staff. These limitations result in SARS-CoV-2 surveillance blackouts across several countries. Here we propose a rapid and accessible protocol based on Sanger sequencing of a single PCR fragment that is able to identify and discriminate all SARS-CoV-2 variants of concern (VOCs) identified so far, according to each characteristic mutational profile at the Spike-RBD region (K417N/T, E484K, N501Y, A570D). Twelve COVID-19 samples from Brazilian patients were evaluated for both WGS and Sanger sequencing: three P.2, two P.1, six B.1.1 and one B.1.1.117 lineage. All results from the Sanger sequencing method perfectly matched the mutational profile of VOCs and non-VOCs RBD's characterized by WGS. In summary, this approach allows a much broader network of laboratories to perform molecular surveillance of SARS-CoV-2 VOCs and report results within a shorter time frame, which is of utmost importance in the context of rapid public health decisions in a fast evolving worldwide pandemic. • We propose and validate a protocol based on Sanger sequencing that discriminate the circulating SARS-CoV-2 variants; • This approach allows a broader network of laboratories to perform molecular surveillance of SARS-CoV-2 VOCs; • The method is sensitive to known relevant Spike-RBD mutations and potentially to new mutations. [ABSTRACT FROM AUTHOR]