15 Oct 2019


I like to avoid colds and other nasties, so inspired by Global Handwashing Day, I’ve gathered together links and notes on handwashing and related subjects.

The basics

Wash your hand properly: regular soap and water, all parts of the hand and wrist, and dry with a paper towel. The soap and mechanical action of washing rips a virus apart and removes bacteria. You don’t need anything else.

There are plenty of step-by-step guides and videos:

You can dry your hands with just one piece of paper:

The importance of hand drying is from: Coronavirus and handwashing: research shows proper hand drying is also vital, The Conversation, 5 March 2020.

Resist touching your face and eyes

Touching your mouth, nose or eyes is a good way to self contaminate yourself. Resist it.

“A behavioral study of medical students at the University of New South Wales found that of the 26 participants, students touched their face an average of 23 times per hour and 44 percent of the time it was in contact with a mucous membrane.”

Source: Why washing your hands well is so important to protect your family from the flu, The Conversation, 23 October 2018.

Hand sanitizers

Prefer hand washing and avoiding touching your face. However:

“If you touch your face (as most of us do), you might like to use a hand rub after leaving the train or bus, as hand hygiene can reduce the spread of respiratory illnesses by 20% and by 30% for gastrointestinal infections.”

Source: Health Check: should we be using alcohol-based hand sanitisers?, The Conversation, 1 Aug 2016.

There’s a fun discussion of hand sanitizers on The Best Thing Since Sliced Bread? podcast, the Winter bugs: Hand sanitisers episode from 13 Feb 2019. My take-away from that episode was to avoid antibacterial (non-alcohol) hand sanitisers due to the risk of antibiotic resistance. Plus, they typically come in a plastic container, so there’s that too.


“If soap and water are not unavailable, the CDC recommends using an alcohol-based hand sanitizer that contains at least 60 percent ethanol. Alcohols have a broad-spectrum of antimicrobial activity and are less selective for bacterial resistance compared to other antibacterial chemicals.”

Source: Why washing your hands well is so important to protect your family from the flu, The Conversation, 23 October 2018.

Nasal sprays

Maybe: Nasal sprays create a hostile (acidic) environment in your nose.

No huge studies yet, but this is a plausible mechanism to give you protection from someone who has just sneezed near you. However, it’s not clear how long the effect lasts.

See: The Best Thing Since Sliced Bread?, 13 Feb 2019 episode, Winter bugs:Vitamin C and zinc.

Flu vaccination


“The best time to have a flu vaccine is in the autumn, from the beginning of October to the end of November.”

Source: Flu vaccine overview, NHS, 16 July 2019.

Face coverings (surgical masks, cloth masks)

To protect yourself, no. Partly because people don’t wear them properly, get a false sense of security, and touch the masks. (Of course, it’s more complicated than that.)


“If you are likely to be in close contact with someone infected, a mask cuts the chance of the disease being passed on. If you’re just walking around town and not in close contact with others, wearing a mask is unlikely to make any difference.”

Source: Yes, it is worse than the flu: busting the coronavirus myths, The Guardian, 3 March 2020, 10:50 GMT.

On the other hand, if you are ill yourself (and can’t stay away from others) or you’re caring for someone ill, that might be different.

“If you are coughing or sneezing and therefore producing droplets that can contaminate other people or surfaces, wear a surgical mask to protect others. Even if you think it’s just a cold, wear a mask, or if you don’t have one, then a scarf. Pretty soon we may all be asked to wear these when we go to public places even if we aren’t coughing or sneezing, if some people don’t take this responsibility very seriously.”


The Guardian has published a useful video on face masks, describing the different kinds, the problems, and alternatives.

Disinfect your phone screen

It is the case that viruses and bacterial live on phones, but it’s unclear how bad the transmissions is from the phone or what the clearing schedule should be.

I’m more thinking of not taking my phone out as much.

However, we do have one source suggesting using a wipe on your phone twice a day (perhaps before lunch and then before dinner).

“A recently published study estimates that viruses like COVID-19 may be able to persist for up to nine days on smooth glass and plastic surfaces, like a mobile phone screen.”

Source: Coronavirus: How behaviour can help control the spread of COVID-19, The Conversation, 26 Feb 2020.


In the UK, take vitamin D supplement in the autumn and winter.

Looking at 41 clinical trials with more than 30,000 participants, there’s an overall 20% protective effect from vitamin D. That is, someone taking a vitamin D supplement is 20% less likely to experience an acute respiratory infection compared with someone who is not taking the supplement.


Regarding other vitamins:

“Regular ingestion of vitamin C had no effect on common cold incidence in the ordinary population, based on 29 trial comparisons involving 11,306 participants”

…although it can reduce the duration, but this is only by 8% so not worth taking a vitamin C supplement every day for this.

Source: Vitamin C for preventing and treating the common cold, Cochrane, Jan 2013.

If you do get a cold…

Still no conclusive effect if you take vitamin C therapeutically (when you have a cold).

Take 75 mg to 100 mg zinc when you are ill (obviously, along with everything else in this post, your medical circumstances may be different). This can reduce the duration of a cold by a third (maybe 2 days).

This has to take effect at the back of your throat, so go for a lozenge (ionic zinc). Avoid (the often added) citric acid, tartaric acid, fats, vitamin C as these nullify the effect of the zinc!.

See: The Best Thing Since Sliced Bread?, 13 Feb 2019 episode, Winter bugs:Vitamin C and zinc.