Use of ivermectin and factors associated with the prevention and/or treatment of COVID-19: a cross-sectional online survey in the province of Chincha, Peru [version 2; peer review: 2 approved]

Background: Peru has reported one of the highest mortality rates by COVID-19 worldwide. The Chincha province has been one of the most affected regions in Peru and the leading promoter of the use of ivermectin for the treatment of COVID-19. Therefore, our study aimed to evaluate the frequency of use and factors associated with the use of ivermectin for COVID-19 in Chincha. Methods: A cross-sectional study was conducted during the second wave of COVID-19 in Peru. For statistical analyses, frequencies and percentages were reported. Prevalence ratios (PR) with a 95% confidence interval (CI), and a p-value of 0.05 were used to determine statistical significance. The SPSS version 22 (IBM Corp) program was used for the analyses. Results: A total of 432 participants were included in the study; of these, 67.6% (n = 292) used ivermectin during the COVID-19 pandemic, with 20.20% (n=59) using ivermectin only for prophylactic purposes, while 41.79% (n=122) used it only as treatment for COVID-19. The consumption of ivermectin was associated with age ≥ 50 years (PR:1.27, 95% CI:1.04–1.54), technical education level (PR:1.16, 95% CI:1.01–1.34), symptoms of COVID-19 with negative/no diagnosis (PR: 1.28, 95% CI: 1.07–1.53), positive diagnosis (PR:1.38, 95% CI:1.18–1.61), and positive contact with infected people (PR:1.45, 95% CI:1.06–1.98). Conclusions: Most people in Chincha used ivermectin during the second wave of the COVID-19 pandemic. The main factors associated with the use of ivermectin for the prevention/treatment of COVID-19 were age ≥50 years, having a technical education level, having had symptoms with negative/no diagnosis or positive diagnosis, and contact with people infected with SARS-CoV-2

G protein signaling in the parasite Entamoeba histolytica

The parasite Entamoeba histolytica causes amebic colitis and systemic amebiasis. Among the known amebic factors contributing to pathogenesis are signaling pathways involving heterotrimeric and Ras superfamily G proteins. Here, we review the current knowledge of the roles of heterotrimeric G protein subunits, Ras, Rho and Rab GTPase families in E. histolytica pathogenesis, as well as of their downstream signaling effectors and nucleotide cycle regulators. Heterotrimeric G protein signaling likely modulates amebic motility and attachment to and killing of host cells, in part through activation of an RGS-RhoGEF (regulator of G protein signaling–Rho guanine nucleotide exchange factor) effector. Rho family GTPases, as well as RhoGEFs and Rho effectors (formins and p21-activated kinases) regulate the dynamic actin cytoskeleton of E. histolytica and associated pathogenesis-related cellular processes, such as migration, invasion, phagocytosis and evasion of the host immune response by surface receptor capping. A remarkably large family of 91 Rab GTPases has multiple roles in a complex amebic vesicular trafficking system required for phagocytosis and pinocytosis and secretion of known virulence factors, such as amebapores and cysteine proteases. Although much remains to be discovered, recent studies of G protein signaling in E. histolytica have enhanced our understanding of parasitic pathogenesis and have also highlighted possible targets for pharmacological manipulation