RESUMO
Over the past few decades, several publications have investigated the role of Epstein-Barr virus (EBV) in head and neck squamous cell carcinomas, and an increasing number of them have shown its presence in laryngeal tumors. The purpose of this meta-analysis was to evaluate the association of EBV with laryngeal carcinoma. The search was carried out in two databases, Scopus and PubMed, using the following terms: "Epstein-Barr virus" and "laryngeal carcinoma". A total of 187 records were found, of which 31 were selected for meeting the inclusion and exclusion criteria. The meta-analysis yielded an overall pooled prevalence of 43.72% (95% confidence interval (CI): 34.35-53.08). Studies carried out in Europe and Eurasia had slightly higher pooled prevalence than other subgroups, while the prevalence of studies performed in developed countries was higher than in developing countries (46.37% vs. 34.02%). Furthermore, laryngeal carcinoma occurred almost three times as often among EBV-infected individuals compared to those without EBV infection (odds ratio = 2.86 (95% CI: 1.18-6.90); Begg's test, p = 0.843 and Egger's test, p = 0.866). Our findings support the idea that EBV is related to laryngeal carcinoma. However, further studies are needed before recognizing a definitive etiological role of EBV in the development and/or progression of laryngeal carcinomas.
RESUMO
Despite the recent announcement of the new pathogenic coronavirus to man, SARS-CoV2, a large number of publications are presented to the scientific community. An organized and systematic review of the epidemiological, etiological, and pathogenic factors of COVID-19 is presented. This is a systematic review using the databases MEDLINE, EMBASE, Web of Science, SCIELO; the descriptors coronavirus, SARS-CoV-2, etiology, epidemiology, pathophysiology, pathogenesis, COVID-19, with publications from December 2019 to January 2021, resulting in more than 800 publications and 210 selected. The data suggest that COVID-19 is associated with SAR-CoV-2 infection, with the transmission of contagion by fomites, salivary droplets, and other forms, such as vertical and fecal-oral. The bat and other vertebrates appear to be reservoirs and part of the transmission chain. The virus uses cell receptors to infect human cells, especially ACE2, like other coronaviruses. Heat shock proteins have different roles in the infection, sometimes facilitating it, sometimes participating in more severe conditions, when not serving as a therapeutic target. The available data allow us to conclude that COVID-19 is a pandemic viral disease, behaving as a challenge for public health worldwide, determining aggressive conditions with a high mortality rate in patients with risk factors, without treatment, but with the recent availability of the first vaccines.