West Nile virus emergence in humans in Extremadura, Spain 2020.

In Spain, the largest human West Nile virus (WNV) outbreak among humans was reported in 2020, constituting the second most important outbreak in Europe that season. Extremadura (southwestern Spain) was one of the affected areas, reporting six human cases. The first autochthonous human case in Spain was reported in Extremadura in 2004, and no other human cases were reported until 2020. In this work, we describe the first WNV human outbreak registered in Extremadura, focusing on the most important clinical aspects, diagnostic results, and control actions which followed. In 2020, from September to October, human WNV infections were diagnosed using a combination of molecular and serological methods (an in-house specific qRT-PCR and a commercial ELISA for anti-WNV IgM and IgG antibodies) and by analysing serum, urine, and/or cerebrospinal fluid samples. Serological positive serum samples were further tested using commercial kits against related flaviviruses Usutu and Tick-borne encephalitis in order to analyse serological reactivity and to confirm the results by neutralisation assays. In total, six cases of WNV infection (five with neuroinvasive disease and one with fever) were identified. Clinical presentation and laboratory findings are described. No viral RNA was detected in any of the analysed samples, but serological cross-reactivity was detected against the other tested flaviviruses. Molecular and serological methods for WNV detection in various samples as well as differential diagnosis are recommended. The largest number of human cases of WNV infection ever registered in Extremadura, Spain, occurred in 2020 in areas where circulation of WNV and other flaviviruses has been previously reported in humans and animals. Therefore, it is necessary to enhance surveillance not only for the early detection and implementation of response measures for WNV but also for other emerging flaviviruses that could be endemic in this area.

Beta-cell mass adaptation to ileum nutrient flow. An experimental model.

The population with obesity has increased at an alarming rate during this century. Bariatric surgery has been demonstrated to be a good method to control weight and, most importantly, associated comorbidities, such as type 2 diabetes mellitus or high blood pressure. The reason why this happens even before losing significant weight remains unclear. Many authors believe that incretins play a main role, triggering special functions of the digestive tract. In reports, these hypotheses are known as foregut and hindgut theories. Initially, the theories were mutually exclusive; additionally, many other propositions have been analysed, according to different surgical techniques (e.g., bile acids and specific enterohormonal components). To elucidate the participation of the ileum, we developed a surgical technique to study the rapid response to nutrients in the ileum. Our goal was to study the stress functional test and histological changes in the pancreas that may explain the variations in glycaemic homeostasis in our rat model. After the oral glucose tolerance test, the experimental group presented an increased insulin release response with conserved glycaemia. We report an increasing beta-cell mass in the experimental group (+11.87 mg vs. +9.65 mg, respectively), while alpha-cell mass was not different. Based on transcription factors, the pathways that were increased were the proliferation process (as the number of PCNA-positive cells in the experimental group versus sham (+12.06 vs. +6.2 PCNA+ cells/mm²)) and transdifferentiation (ARX; +2.67 ARX+ cells/mm² in the experimental group vs. +2.04 ARX+ cells/mm² in the controls). We report the consequences of the rapid arrival of nonprocessed nutrients to the ileum on the endocrine cellular pancreas. The ileum could be a principal effector in the enterohormonal axis, which conditions endocrine pancreas cellularity.