I missed Ethanol production in the supply chain for yesterdays article. It is the way to get alcohol for sanitizer. There are fewer supply chain issues for the wide-scale adoption of WHO local production plans for developing countries and scaling sanitizer production in the developed world. If Ethanol is denatured it is good as the key sanitizer ingredient.
Tereos, one of the largest producers of bioethanol alcohol in the European Union and headquartered in northern France, said it also saw a spike in demand and had a special order for 20,000 hectoliters (528,000 gallons about 2,000 tons) of additional denatured alcohol in the past days.
Here is a 9-pager on how even a hospital in Rwanda was able to make their 100 liter per month of hand sanitizer. It cost them one-third the commercial price. They made it for $2.65 per liter.
Social distancing and quarantines and mass cleaning can work to stop coronavirus. China showed that was the case.
The additional use of hand sanitizer makes group gatherings safer by up to about 70%. This is especially true if there are procedures (such as hourly announcements commanding everyone to clean their hands). If everyone has their own supply of hand sanitizer (about 100 milliliters for one week), then compliance will take about 20 seconds on the spot and without lines.
An MIT computational simulation of hand sanitizer usage at nearly once an hour frequency is projected to reduce disease transmission by up to 70%. This was based upon an airport study, but the hand cleanliness analysis seems more broadly applicable. The WHO and CDC all indicate that hand cleaning and social distancing are critical actions. The percentage of impact may vary but the case that it is has significant benefit seems uncontroversial.
Hand Cleaning Background
A scientific study on the effects of hand washing on the bacterial contamination of hands showed that, after a deliberate contamination of individuals by touching door handles and railings in public places, bacteria were found in 44% of the sample. This percentage was reduced to 23% after handwashing with water alone, and to 8% after hand washing with water and plain soap (Burton et al., 2011). The same study showed that the effect of handwashing does not depend on the bacteria species.
Hand hygiene is considered as the first prevention step in the case of an epidemic emergency. The MIT study makes the case for it as a mitigation strategy against global epidemic spreading. They studied contagion dynamics through the world air‐transportation network. They see an impact of hand‐hygiene behavioral changes on the diffusion of infections worldwide.
To be infected, a healthy individual needs to touch a contaminated surface or come into contact directly with an infected person. If the individual is healthy and touches a contaminated surface—regardless of how long ago he/she washed his/her hands—he/she will get the bacteria on hands. However, if he/she washes hands soon after he/she gets contaminated, there is a significant probability of removing that bacteria from the hands before being transmitted to body fluids.
A survey performed by the American Society for Microbiology (2003), which revealed that 30% of travelers do not wash their hands after using the public toilets at airports, implying that the remaining 70% are compliers with hand washing. Following a study in a college town environment, they consider that only the 67% of the compliers wash their hands properly.
The percentage of passengers in an airport that have cleaned hands is about 20%. It had an upper bound of 24%.
The frequency of handwashing follows a normal distribution with mean equal to 4.5 hours and standard deviation equal to 1 hour. They consider that the duration of cleanliness of hands after hand washing follows an exponential distribution with mean value equal to 1.5 hours.
Hourly Handwashing Everywhere
Hourly hand washing/cleaning should achieve 65-75% clean hands.
Frequent hand sanitizer use has already been done by nurses and doctors in hospitals. Carrying personal hand sanitizer bottles is part of optimal compliance in hospitals.
Scaling to Hourly Hand Cleaning
Each ton is about 10000 people per week using hourly hand cleaning. We could stretch this as it is convenient for them to wash hands 3-5 times per day after they go to the bathroom. When rationing, think about which facility needs the least transmission. How many people are in the facility? Divide by 10000. Give a 100ml bottle or two 50 ml bottles per week to each person.
We will ultimately need hand cleaning every hour for 80% of the world population for about 6 billion people to fully open the world economy. Here is an analysis of the scale of global mobilized sanitizer as we move to re-opening
Each person following the hourly cleaning:
20 milliliters per day per person.
600 milliliters per month per person. But with waste and inefficiency, that is 1 liter per person.
Ultimately 6 million tons of sanitizer per month or 72 million tons per year.
Focus initial supplies on the critical areas that cannot be shutdown. Hospitals, police, fire departments, military, prisons other key operations. Use it in the hardest-hit areas first.
Optimal hand cleaning is similar to a physical vaccine in disease spread reduction.
SOURCES- Analysis by Brian Wang, Extrapolation on MIT Studies, CDC & WHO reports, The Lancet studies of hospital use of hand sanitizer
Written by Brian Wang