Precautions with regard to sexual「comparisons, rates, proportions with diseases」need no further explanation:
　「One in two sexually active persons will contract an STI by age 25. …Researchers estimate that at least 80% of sexually active people will have an HPV infection at some point in their lifetime. CDC data for 2013–2014 show that about 42% of men and 40% of women aged 18-59 had genital HPV at that time. …About 1 in 8 people aged 14-49 in the U.S. has genital herpes. …Symptoms of genital herpes often go unnoticed. Most people with genital herpes—close to 90%—don't know they have the infection. Globally, researchers estimate that about two-thirds of the population under age 50—more than 3.7 billion people—are infected with HSV-1. Some 140 million people aged 15-49 are infected with genital HSV-1, primarily in the Americas, Europe and Western Pacific. …In 2015, rates of the three most common reportable STIs—chlamydia, gonorrhea and syphilis—reached a record high level. The approximately 1.5 million reported cases of chlamydia represent the highest number of annual cases of any condition ever reported to CDC. …Young people ages 15 to 24 years old accounted for 65% of chlamydia diagnoses and 50% of gonorrhea diagnoses in 2015.」And so on.
　　[　https://oklahoma.gov/content/dam/ok/en/health/health2/documents/std-trends-2015-cdc.pdf 2019-12-04　]　
　「Hand stroking shafts inevitable」: for what it is worth, assuming no one is telling lies:「78 percent of adults in the world masturbate, including: 96 percent of British men, 93 percent of German men, and 92 percent of American men. 78 percent of British women, 76 percent of German women, and 76 percent of American women」
　　[　https://www.prnewswire.com/news-releases/worlds-largest-masturbation-survey-uncovers-how-traditional-views-of-masculinity-prevent-men-from-having-fulfilling-sex-lives--relationships-300638644.html 2020-01-23　]　
　Without a doubt, the Irish also have knowledge of their own to pass along in these trying times:「Masturbation will not spread coronavirus, especially if you wash your hands (and any sex toys) with soap and water for at least 20 seconds before and after.」Nonetheless and regrettably, unlike in dynastic China, it must be undertaken alone to truly be a preventative countermeasure but still achieve the desired result with some degree of safety.
　 　[　https://www.sexualwellbeing.ie/sexual-health/sex-and-coronavirus/ 2020-03-31　]　
　The Dutch, too have the same solution—it seems masturbation has become mainstream in the media the world over due to the coronavirus (it has always been 'the main stream' in reality, albeit covertly for most folks):
　「'Don't have sex with your partner if they have been isolated because of (suspected) coronavirus infection,' the RVIM says. 'Sex with yourself or with others at a distance is possible (think of telling erotic stories, masturbating together).'」
　　[　https://www.theguardian.com/world/2020/may/15/dutch-official-advice-to-single-people-find-a-sex-buddy-for-lockdown-coronavirus 2020-05-16　]　
　Needless to point out perhaps, but Chinese shamans from antiquity hit upon the same solution as a pandemic preventative countermeasure, honed for ultimate client satisfaction by utilizing naked females with no-longer-integrated feet as masturbatory sex buddies available for short-term rental with erotic visualization of live prepubescent female genitalia engaging in autoerotic stimulation herself, as a solution to the same problem facing us now, but in pre-Internet days.

Modern definitions (that generally disregard history) …excluding politically incorrect concepts and other meanings deemed offensive today; may list only pigeonholed definitions, euphemisms, or meaningless mnemonics)
Chinese: careful; to prevent
Unihan extended: guard against, take care; caution
EDRDG: guard against; take care; caution