In recent days there have been an increase in questions related to the COVID-19 pandemic. These range from questions about homemade hand sanitiser formulations to increasingly outlandish theories for disinfection.

Although some of the responses given have been sensible, I cannot help but feel that it is also not correct to provide any kind of advice on a global health crisis on SE. This is especially so in light of how little we understand about the virus. To provide any reliable response to the situation, we would need to police the content extremely carefully to make sure that there isn't any "fake news" that has otherwise been so prevalent on the Internet. This needs genuine experts in the field, and the cold hard truth is that we don't have this kind of expertise.

I am of the opinion that at the very least, we need to promptly close all such questions with the personal medical question close reason. And we should seriously consider deleting such questions in order to stop any speculation in the comments. Opinions are welcome (whether agreeing or dissenting), but we should try to reach a decision very soon.

  • 3
    $\begingroup$ Related thread on Biology: Information about Coronaviruses $\endgroup$ – orthocresol Mar 16 '20 at 8:05
  • 8
    $\begingroup$ Yeah, you should keep your closehammer ready. $\endgroup$ – Mithoron Mar 16 '20 at 16:32
  • 2
    $\begingroup$ I think we will close as PMQ, at the very least. Optionally redirecting people to the comments on the answer. I think we are pretty much already following this strategy, so to the community, please carry on with your excellent work. $\endgroup$ – orthocresol Mar 19 '20 at 8:31
  • $\begingroup$ Every additional infection that can be averted, irrespectively of how this is accomplished (without bringing harm to someone else, of course) is very important : nytimes.com/2020/03/13/science/… $\endgroup$ – Buck Thorn Mar 19 '20 at 17:01
  • 4
    $\begingroup$ See also: nytimes.com/2020/03/19/health/… I am somewhat disappointed by the attitude here: "we are smart enough to answer questions on some incredibly advanced topics that are mostly of interest to a few ivory tower chemists, but we find answering basic questions about a simple topic that can save a lot of lives completely baffling". $\endgroup$ – Buck Thorn Mar 19 '20 at 17:02
  • $\begingroup$ @BuckThorn - A man has got to know his limitations. Clint Eastwood as Dirty Harry "In Magnum Force." The point is not to stop the spread of "good" information, but to stop the spread of opinions and debates that just confuse the general public. There are plenty of "authoritative" sources like the United Sates CDC on the web that should be used rather than us. $\endgroup$ – MaxW Apr 5 '20 at 1:20
  • $\begingroup$ @MaxW I agree: including links to reliable sites and recommending that people get their information from those sites is the best response. I have a minor bone to pick regarding orthocresols answer, however. The answer is well meant and makes similar arguments to your comment, but it also makes unnecessary assumptions about the ability of this community to properly answer questions regarding the formulation and anti-viral properties of detergents and denaturants (when not obviously off-topic), particularly if comments and answers properly reference authoritative sources. $\endgroup$ – Buck Thorn Apr 6 '20 at 11:26

I partly disagree. There is nothing mysterious about what needs to be done. Wash your hands regularly and properly. Detergents denature viruses. No mystery in this physicochemical process. Other behavioral modifications need not be addressed in this site.

And, yes, medical questions are usually inappropriate. However, this is an opportunity for the site to perform a potentially valuable service to the general public. Regarding DIY sanitizers, I would shut down requests for recipes or instruction that might place the OP or others in danger, a reaction similar to any other post. Label questions as dupes and link to an appropriate existing post. Otherwise I suggest having a standard response with links to appropriate and more official sites.

This website does not exist to spread public health information. However, in the best interests of the public under what can clearly be considered a global crisis, it is worth reconsidering how to handle certain questions.

I quote the comments under a recent post:

No significant difference, both will disrupt the lipid bilayer of virus particles – Waylander 6 hours ago

@Waylander are you saying the alcohol component in sanitizers is not needed? That common detergent 'soaps' will kill virus? –MarsJarsGuitars-n-Chars 4 hours ago

Alcohol based sanitisers and soaps are two different things. With a sanitiser you need an alcohol concentration of at least 60% and a long contact time. Common detergents (e.g. hand soap) do 2 things, they break up the lipid bilayer of virus particles and they facilitiate the mechanical removal of the virus from a surface (provided you rinse it off well). A soap is not a sanitiser and a sanitiser is not a soap, you use them under different circumstances. – Waylander 4 hours ago

@MarsJarsGuitars-n-Chars Since you ask, yes soap does kill viruses vox.com/science-and-health/2020/3/11/21173187/… – Waylander 3 hours ago

@Waylander Awesome. Thanks. Makes good sense. Wonder why this is not being stressed in news reports, etc.. The mechanical action I knew about. Strange this is not more common knowledge.


The guidelines are pretty clear, from the CDC (including this link):

Clean your hands often

  • Wash your hands often with soap and water for at least 20 seconds especially after you have been in a public place, or after blowing your nose, coughing, or sneezing.
  • If soap and water are not readily available, use a hand sanitizer that contains at least 60% alcohol. Cover all surfaces of your hands and rub them together until they feel dry.
  • Avoid touching your eyes, nose, and mouth with unwashed hands.

Clean and disinfect

  • Clean AND disinfect frequently touched surfaces daily. This includes tables, doorknobs, light switches, countertops, handles, desks, phones, keyboards, toilets, faucets, and sinks.
  • If surfaces are dirty, clean them: Use detergent or soap and water prior to disinfection.
  • Cleaning refers to the removal of germs, dirt, and impurities from surfaces. Cleaning does not kill germs, but by removing them, it lowers their numbers and the risk of spreading infection.
  • Disinfecting refers to using chemicals to kill germs on surfaces. This process does not necessarily clean dirty surfaces or remove germs, but by killing germs on a surface after cleaning, it can further lower the risk of spreading infection.

To disinfect: Most common EPA-registered household disinfectants will work. Use disinfectants appropriate for the surface. Options include:

  • Diluting your household bleach. To make a bleach solution, mix: 5 tablespoons (1/3rd cup) bleach per gallon of water OR 4 teaspoons bleach per quart of water

    Follow manufacturer’s instructions for application and proper ventilation. Check to ensure the product is not past its expiration date. Never mix household bleach with ammonia or any other cleanser. Unexpired household bleach will be effective against coronaviruses when properly diluted.

  • Alcohol solutions. Ensure solution has at least 70% alcohol. Make sure the alcohol is intended for topical application, for instance rubbing alcohol. Do not use just any denatured alcohol
  • Other common EPA-registered household disinfectants. Products with EPA-approved emerging viral pathogens claims are expected to be effective against COVID-19 based on data for harder to kill viruses. Follow the manufacturer’s instructions for all cleaning and disinfection products (e.g., concentration, application method and contact time, etc.).

Complete disinfection guidance

  • 3
    $\begingroup$ "Otherwise I suggest having a standard response with links to appropriate and more official sites." I would also be willing to support this. It would be a sensible option to have a basic list of common responses, and close questions as a duplicate of that. The main question is can we get one together in good time? Do we have some people who are willing to find the appropriate resources? $\endgroup$ – orthocresol Mar 16 '20 at 13:14
  • 1
    $\begingroup$ @orthocresol: Here is a useful link provided by an authorative source: cdc.gov/handwashing/when-how-handwashing.html Other countries should provide similar information. I suggest this be compiled in this meta post or a regular post. $\endgroup$ – Buck Thorn Mar 16 '20 at 14:10
  • 1
    $\begingroup$ another: cdc.gov/coronavirus/2019-ncov/prepare/prevention.html $\endgroup$ – Buck Thorn Mar 16 '20 at 14:13
  • 1
    $\begingroup$ en español: cdc.gov/handwashing/esp/show-me-the-science-hand-sanitizer.html $\endgroup$ – Buck Thorn Mar 16 '20 at 14:16
  • $\begingroup$ mas en español: cdc.gov/handwashing/esp/show-me-the-science-handwashing.html $\endgroup$ – Buck Thorn Mar 16 '20 at 14:18
  • $\begingroup$ Hand washing instructions from the WHO: who.int/gpsc/clean_hands_protection/en $\endgroup$ – Buck Thorn Mar 16 '20 at 14:31
  • 1
    $\begingroup$ I agree too. We could post one on this very page. But I feel we might not be able to address the gravest issue: the dearth of sanitizers and disinfectants in the market (the biggest reason we have so many posts on "recipes for DIY sanitizers"). In such cases I feel the safest way is to close as PMQ just as @ortho had mentioned. I like the idea of SE being a help for general public, to clear out certain myths and fake news and discourage such home-experiments without proper safety. $\endgroup$ – Sir Arthur7 Mar 16 '20 at 17:54
  • 3
    $\begingroup$ In for a penny, in for a pound. -- I just don't think that we can get "partially" into this discussion. Trying to answer "theoretical" disinfectant questions will only lead to more chaos. $\endgroup$ – MaxW Mar 17 '20 at 7:51
  • $\begingroup$ @MaxW It's all clearly explained here + links above: cdc.gov/coronavirus/2019-ncov/prepare/prevention.html Where's the "theory"? $\endgroup$ – Buck Thorn Mar 17 '20 at 13:58
  • 1
    $\begingroup$ @BuckThorn - I was referring to "theoretical" questions being asked on the Chemistry site. $\endgroup$ – MaxW Mar 17 '20 at 14:17
  • 1
    $\begingroup$ Excessive handwashing, like disinfecting (outside of a highly and freshly contaminated (and likely with other, bacterial diseases) hospital environment) is unlikely to have any significant effect on these covid infections. Respiratory diseases spread via droplet infections, period. There is zero evidence that corona is an exeption here. $\endgroup$ – Karl Mar 31 '20 at 21:26
  • 1
    $\begingroup$ @BuckThorn Of course it is not ruled out. I would say it´s certainly possible, and likely, if your finger carries a high concentration of viruses and you stick it into your running nose for a minute. But if it was a realistic scenario, there should now be cases documented. That is not the case. WHO etc., when asked, still say nothing as "it´s theoretically possible". That is beneath contempt. These handwashing ads everywhere are spreading panic, but most likely do nothing else. $\endgroup$ – Karl Apr 2 '20 at 17:42
  • 4
    $\begingroup$ @BuckThorn I haven´t, being a bloody chemist. ;) But if it was important, the doctors should be able to come up with some evidence. I have never, through all the flu epidemics in my life, heard sth. like "last years flu was spread by smear infections in 11(+-4)% of cases". We know these numbers for other (typically gastrointestinal) diseases. For respiratory diseases, the doctors seem to not care. I don´t know, but my strong, strong suspicion is that the number is too low to care. $\endgroup$ – Karl Apr 2 '20 at 18:42
  • 2
    $\begingroup$ The back and forth between users Buck Thorn and Karl is exactly why I think we should just stay out this. I understand the difference between probabilities and possibilities, but I'll guarantee you that the general public doesn't. $\endgroup$ – MaxW Apr 5 '20 at 1:08
  • 2
    $\begingroup$ @MaxW That´s the way politicians think: The general public ist stupid and must not be bothered with details. A nice selffulfilling prophecy. $\endgroup$ – Karl Apr 11 '20 at 18:41

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .