Dr. Pragya Khanna
“Wash your hands when you get home, and keep scrubbing them for at least 20 seconds” is good advice, to be followed, with or without the coronavirus. However, there is one big problem, according to the UN more than 40 per cent of the world’s population lives in regions where water is scarce and is increasingly becoming more so.
Today, with Covid-19 present in every continent except Antarctica, washing hands as they should be washed is a hard challenge in many developing countries. Clean water and soap are often in short supply, and many slum dwellers live in homes deprived of running water. According to Swaminathan Natarajan, BBC World Service, about one billion people live in slum-like conditions, making up 30% of the world’s urban population. These housing facilities tend to have very little ventilation, drainage and sewage facilities, with diseases spreading easily.
There are common instances where families comprising of 6-8 people live in one-room house and people cannot move around much without banging into each other. It is not just slum areas that are struggling with the availability of water. All of us know that the cities of Johannesburg, Chennai, Simla and few others almost ran out of water last year and were declared Zero Day.
Shanthi Sasindranath, a mother of two who lives in the outskirts of Chennai told the BBC: “If there is a shortage like last year, it will be difficult to get clean water to wash our hands multiple times.” During the water shortages last year, her family was able to survive by buying untreated water from agricultural wells located more than 50km away.
As for soap, it is not as much of a problem as water. Now how it works is interesting: we generally think of soap as something mild, however, from the standpoint of microorganisms, it is often tremendously destructive. A drop of ordinary soap diluted in water is enough to rupture and kill many types of bacteria and viruses, including the new coronavirus that is presently circling the globe. The secret to soap’s remarkable strength is its hybrid structure.
According to an article published in The New York Times, soap is made of pin-shaped molecules, each of which has a hydrophilic head, it readily bonds with water, and a hydrophobic tail, which shuns water and prefers to link up with oils and fats. These molecules, when suspended in water, alternately float about as solitary units, interact with other molecules in the solution and assemble themselves into little bubbles called micelles, with heads pointing outward and tails tucked inside.
Some bacteria and viruses have lipid membranes that resemble double-layered micelles with two bands of hydrophobic tails sandwiched between two rings of hydrophilic heads. These membranes are studded with important proteins that allow viruses to infect cells and perform vital tasks that keep bacteria alive. Pathogens wrapped in lipid membranes include coronaviruses, H.I.V., the viruses that cause hepatitis B and C, Herpes, Ebola, Zika, dengue, and numerous bacteria that attack the intestines and respiratory tract, as per Prof. Pall Thordarson, acting head of Chemistry at the University of New South Wales.
When you wash your hands with soap and water, you surround any microorganisms on your skin with soap molecules. The hydrophobic tails of the free-floating soap molecules attempt to escape water; in the process, they block themselves into the lipid envelopes of certain microbes and viruses, prying them apart.
Apart from that people are advised to use hand sanitizers, although they are not considered as reliable as soap. Sanitizers with at least 60 percent ethanol do act likewise, defeating bacteria and viruses by destabilizing their lipid membranes, but they cannot easily remove microorganisms from the skin. Then there are certain viruses that do not depend on lipid membranes to infect cells, as well as bacteria that protect their delicate membranes with robust armours of protein and sugar. Examples include bacteria that can cause meningitis, pneumonia, diarrhea and skin infections, as well as the hepatitis A virus, poliovirus, rhinoviruses and adenoviruses (frequent causes of the common cold).
These more hardy microbes are usually less susceptible to the chemical attack of ethanol and soap. But vigorous rubbing with soap and water can still erase these microbes from the skin, which is relatively why hand-washing is more effective than using sanitizer. Alcohol-based sanitizer is a good backup when soap and water are not available.
One article that I came across explained very amusingly that “In an era of robotic surgery and gene therapy, it is all the more wondrous that a bit of soap in water, an ancient and fundamentally unaltered recipe, remains one of our most valuable medical interventions.”
During the course of a day, we pick up all sorts of viruses and microorganisms from the objects and people in the environment. When we inattentively touch our eyes, nose and mouth, a habit, one study suggests, that recurs as often as every two and a half minutes; we offer potentially dangerous microbes a gateway to our internal organs.
Florence Nightingale, the English nurse and statistician, also promoted hand-washing in the mid-1800s, but it was not until the 1980s that the Centres for Disease Control and Prevention issued the world’s first nationally endorsed hand hygiene guidelines. But the technique works only if everyone washes their hands frequently and thoroughly: Work up a good lather, scrub your palms and the back of your hands, interlace your fingers, rub your fingertips against your palms, and twist a soapy fist around your thumbs.
Soap is available to purchase almost everywhere in the world. Most people, including those living in poverty in rural and urban areas, have some kind of basic soap, even if just for laundry. But in this time of crisis, soap supplies may run short or people who lose their income because of the pandemic may find soap not affordable. In New Delhi, Sudhanshu S. Singh, CEO of the non-profit NGO, Humanitarian Aid International, has been collecting donations of soap and hand sanitizer and supplying them to the needy. Similar activities can be taken up in other places as well.
But I again come to the point that for the 2.2 billion people in the world who lack safe drinking water, mostly in low- and middle-income countries, the hand washing advice will be difficult to heed. In these places, water is limited for a number of reasons. It could be due to drought or climate change, or local water supplies could be polluted, or the nearest source of water may be far away from home. The ideal is to use clean, running water to wash away germs because it is less likely to contain harmful pathogens like e-coli, which can make you sick.
In less than ideal conditions, other types of water can be used to wash hands. Non-potable water (for example, water that has been used to clean dishes or do laundry), along with soap, can be effective, according to a 2019 study published in the journal Environmental Science and Technology.
Small-scale solutions work too, like setting up a network of public hand-washing stations, something done in West Africa during the Ebola outbreak of 2014. In the words of Joia Mukherjee, Chief Medical Officer of ‘Partners in Health’ and Associate Professor of Global Health at Harvard Medical School, “When Ebola hit, one of the big concerns was the lack of running water and sanitation for hand-washing and proper waste disposal, it almost seemed like an unsolvable problem. And yet relatively rapidly, solutions were put together. The simplest kind of hand-washing station needs just two buckets. One bucket contained a mix of chlorine and water for the washing, with a spigot so people could tap into the supply, a second bucket, underneath the spigot, caught the wastewater. These hand-washing stations were put in public buildings, schools and markets in Ebola-affected areas and public health officials stressed why it was important to wash hands. Soon people adopted this hand-washing technique everywhere,” says Mukherjee.
“This kind of innovation is exactly what the developing world needs right now to ward off coronavirus”, says Glassman, who is the author of Millions Saved: New Cases of Proven Success in Global Health. “We should deploy and test everything we’ve got,” she says, citing the hand-washing stations. “Affordability and fast availability is what matters now.”
The lower the technology, the better, says Glassman. If people can use objects and materials available in their own communities, like buckets, it makes the solution more likely to work.
Then there is the question of how to keep hand-washing stations safe from being a hot spot for disease transmission. Myriam Sidibe, a senior fellow at the Harvard Kennedy School, is working with the aid group ‘WaterAid’ in Kenya to figure that out. They are trying to find ways to make 10,000 water stations across the country safe for people to congregate around.
The plan is to introduce “social distancing nudges on the ground”, similar to what we are seeing in our own markets nowadays.
With India being the world’s second-most populous country, and having weak health care facilities and growing concerns that there may be an undetected communal spread of the virus, the risks associated with the lack of clean water aren’t being overstated. UNICEF said last week that almost 20% of urban Indians do not have facilities with water and soap at home.
“Clean water is the first line of defense,” said V.K. Madhavan, India chief executive at WaterAid, a global advocacy group for water and sanitation. “If there is no access to clean water, the situation could worsen.”
India’s clean water issues are not new. Hundreds of thousands of people wait in line every day to fill buckets from government water trucks. Hospitals and schools struggle with clean water supplies. People are forced to wash utensils and clothes in dirty water. About 200,000 people die each year in India from diseases related to unclean water. Insufficient water also leads to food insecurity.
In view of this, it is pertinent to mention here that a proper hand wash involves lathering soap and scrubbing hands on both sides for at least 20 seconds, according to WHO guidelines which would use up around two litres of water if the tap is on, or one litre with the tap closed. Around 20 to 40 litres of water is used up every day, with the assumption that every person cleans his/her hands at least 10 times a day, instead of a usual average of five times a day. A family of five members would thus need 100 to 200 litres of water per day only to wash hands. This would result in the generation of around 200 litres of wastewater per day, a 20 to 25 per cent increase in water demand and generation of wastewater from human settlements.
This will further exploit groundwater and increase the volume of untreated wastewater. This situation will be further aggravated in summer, when water supply sources will run dry. We must understand that good hygiene and water saving needs to go hand-in-hand.
There is a need to spread awareness to be water-efficient by closing taps or using taps. We need to re-design demand by reducing water usage so that we reduce water wastage. We need to re-design sewage management so that we treat wastewater to return manure to the land and clean water to our rivers. So, the least you can do is do not waste water. Use water efficiently. You can help by:
• Turning off faucets when not in use
• Shortening the length of showers
• Using low-flow toilets
• Watering plants by hand rather than hose
Let’s strive for a better tomorrow! |
