The results show that the strong turbulent caused by the flushing flow would lift the virus originally in the toilet bowl to a high position. It implies that the toilet-based "SARS-CoV-2" could cause cross-infection among people and teaching the public to use the toilet properly is mandatory. What is worse, two of the COVID-19 reemerging confirmed cases in Beijing have been reported to be infected from a public toilet, which practically proves the danger from the public restroom.
See also: "Colleges Closing: University Outbreaks and Parental Angst."
The CDC has made available the iSearch COVID-19 Portfolio
The iSearch COVID-19 portfolio is NIH’s comprehensive, expert-curated source for publications and preprints related to either COVID-19 or the novel coronavirus SARS-CoV-2. Our COVID-19 Portfolio tool leverages the cutting-edge analytical capability of the iSearch platform, with its powerful search functionality and faceting, and includes articles from PubMed and preprints from arXiv, bioRxiv, ChemRxiv, medRxiv, Research Square, and SSRN. The portfolio is updated daily with the latest available data.
Also of interest in case you missed it, NIH has made available LitCovid
LitCovid is a curated literature hub for tracking up-to-date scientific information about the 2019 novel Coronavirus. It is the most comprehensive resource on the subject, providing a central access to 32917 (and growing) relevant articles in PubMed. The articles are updated daily and are further categorized by different research topics and geographic locations for improved access.
The CDC has made available an interactive tool for self-evaluation of COVID-19 symptoms. Choose "Self-check symptoms" on right.
Here is the disclaimer: "The purpose of the Coronavirus Self-Checker is to help you make decisions about seeking appropriate medical care. This system is not intended for the diagnosis or treatment of disease or other conditions, including COVID-19. This system is intended only for adults who are 18 years and older and currently located in the United States."
Here is a roundup of recent research findings and recommendations for COVID-19 mask materials.
WHO recommendation: "The ideal combination of material for non-medical masks should include three layers as follows: 1) an innermost layer of a hydrophilic material (e.g. cotton or cotton blends); 2), an outermost layer made of hydrophobic material (e.g., polypropylene, polyester, or their blends) which may limit external contamination from penetration through to the wearer’s nose and mouth; 3) a middle hydrophobic layer of synthetic non-woven material such as polypropylene or a cotton layer which may enhance filtration or retain droplets." https://arstechnica.com/science/2020/06/who-now-recommends-the-public-use-masks-good-masks-in-covid-19-areas/
Good overall summary: "In a recent paper that hasn't yet been peer-reviewed, researchers in the UK determined that "hybrid" masks – combining two layers of 600-thread-count cotton with another material like silk, chiffon, or flannel – filtered more than 80 percent of small particles (less than 300 nanometres) and more than 90 percent of larger particles (bigger than 300 nanometres). They found that the combination of cotton and chiffon offered the most protection, followed by cotton and flannel, cotton and silk, and four layers of natural silk. The researchers suggested that these options may even be better at filtering small particles than an N95 mask, though they weren't necessarily better at filtering larger particles. The team also found that two layers of 600-thread-count cotton or two layers of chiffon might be better at filtering small particles than a surgical mask." https://www.sciencealert.com/some-masks-are-better-than-others-here-they-are-ranked-best-to-worst"
"For Ebola-sized particles, the N95 mask, surgical mask, and HEPA filter performed best, capturing over 99% of particles 1.0 micron and above. Next up, the HERO coffee filter captured 98%. Paper towels, canvas, denim, and the cotton bed sheet also captured more than 90%." https://smartairfilters.com/en/blog/best-diy-coronavirus-homemade-mask-material-covid/"
"Tests performed at the Wake Forest Institute for Regenerative Medicine in Winston-Salem, N.C., showed good results for homemade masks using quilting fabric. Dr. Segal, of Wake Forest Baptist Health, who led the study, noted that quilters tend to use high-quality, high-thread count cotton. The best homemade masks in his study were as good as surgical masks or slightly better, testing in the range of 70 to 79 percent filtration. Homemade masks that used flimsier fabric tested as low as 1 percent filtration, Dr. Segal said." https://www.nytimes.com/article/coronavirus-homemade-mask-material-DIY-face-mask-ppe.html
"Researchers at a Texas A&M University lab tested which household items do the best job of blocking particles in the aAn N95 mask blocks 100 percent of particles. A coffee filter would only block 25 percent of the coronavirus floating through the air. A bandana folded in two layers isn't much better; only 28 percent of particles are blocked. The study found you are much better off using a polyester shower curtain or cotton pillowcase. Both were around 55 percent effective. The Texas A&M lab found the next best option is a bra cup, which blocks 83 percent of airborne particles. The household fabrics that performed the best are vacuum bags and air purifier filters. Vacuum bags protect you against 94 percent of particles in the air. Air filters were just as effective as N95 masks." https://www.khou.com/mobile/article/news/health/coronavirus/which-fabrics-protect-best-for-diy-masks/285-452ada0c-48b8-4ce0-b6b5-7479412133a6