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www.thevillagenews.co.za
17 June 2020
MY WELLNESS
Lockdown 3: balancing the risks of everyday activities Writer Hedda Mittner
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fter so many weeks in a hard lockdown, many of us are still struggling to cope with our new “freedom”, maybe even more so than in most other countries, where the lockdown regulations were only relaxed after the peak in infection rates had passed. Here, on the other hand, many of us are now allowed to go to work, our children are going back to school, we may go to church and use public transport, even though the expected peak is still several weeks off. The trick now is to find a balance between safety and liberty as we resume our normal activities and routines. So just how big are the risks we face every day – and what can we do to stay as safe as possible while minimising the risks of infection and transmission? The question of virus load Epidemiologists and other health experts around the world are still learning about COVID-19 and although many aspects of the disease remain baffling, there are some facts that have emerged. For example, we have been hearing a lot about ‘viral load’ lately. This refers to the critical mass of active virions (infectious virus particles) that have to invade your tissues and begin to reproduce there in order for you to become sick. Research has shown that the risk of COVID-19 infection (in fact, all viral infections) is dependent on the amount of active virus you are exposed to and for how long. There are two ways in which you could be infected by a critical mass (i.e. enough active virions to make you sick) – either by spending a long time (more than an hour) in an environment with a low concentration of active virus (such as in a workplace or a grocery store) or a short time in an environment with
a high concentration of active virus (such as being in the same room with an infected person). Outdoors is safer than indoors The risks increase if you spend that time indoors in an enclosed and poorly ventilated space as opposed to outside in fresh air. The more crowded the environment and the closer you are to the people you are interacting with, especially without wearing masks, the greater the chances that you could get infected. Research studies have found that talking alone can launch thousands of droplets into the air, and that they can remain suspended for eight to 14 minutes. While social distancing (staying more than 1.5m apart) is important, it also becomes a less effective measure the longer you remain indoors with a group of people in a high-risk environment, especially if there is a lot of talking, laughing, heavy breathing or singing involved. Such environments would include public transport, restaurants, movie theatres, gyms, choir practices or singing in church. The reason why these environments are considered high-risk is simply because the particles that are emitted from people’s mouths and noses are the primary vector of infection, and the more time you spend in a room that is permeated by a cloud of virus from other people’s vapours, the more viral particles you will be breathing in. It’s basically the same reason why we get ill more often with colds and flu in winter – it has more to do with the greater amount of time we spend indoors in enclosed spaces than with the colder weather. That is why adhering to safety protocols in the workplace, spacing tables apart in restaurants, staggering seats in theatres, buses and aeroplanes, and limiting the number of people allowed to congregate for funerals
or church services, would lower the risk of infection and transmission. The safest place to be, though, is still outside, where the virus decays much faster than in a windowless, air-conditioned space. Spending time outdoors while practicing social distancing is considered a low-risk activity, which is why it was so illogical to restrict outdoor exercise to a 3-hour time slot during lockdown Level 4. (And why it still seems unreasonable that walkers, swimmers and surfers are not allowed to set foot on a deserted beach or in the ocean!) And while the colder weather may incline you towards keeping windows and doors closed and the heaters switched on, remember to ventilate your house regularly to allow fresh air in. Why wearing a mask is vital As much as people have been complaining about joggers and cyclists not wearing masks, it has to be said that it’s not the easiest thing to do when you need all the oxygen you can get. And surely there are enough wide open spaces in the Overstrand for joggers and cyclists to get their exercise away from more crowded areas such as the cliff path? Just a suggestion, as I see no reason to let your mask slip when there’s no one else around. Wearing a mask when you’re out and about among members of the public, and especially when indoors, however, is vital – for everyone. Not only does this prevent droplets from your nose and mouth from escaping into the air and onto surfaces, but it also slows down the build-up of the virus in a room. This helps to decrease the viral load that is breathed in by others and also limits your own exposure by decreasing the amount of virions being inhaled by you. Is it safe to socialise? While it appears that most people
ESSENTIAL SERVICES – WE ARE OPEN
have started socialising more with neighbours, relatives, friends and colleagues during lockdown Level 3 (contrary to the regulations), it makes sense to restrict your social interactions to as small a number of people as possible outside of your own household. The reason why social gatherings are not permitted is because they usually involve eating and drinking, which is not possible while wearing a mask. So if you are going to socialise, remember that it is safer to do so outside than inside. It is also easier to practise social distancing in the garden than around a dining table inside. It is important to ensure that those you are mingling with can be relied upon to follow the same safety protocols in their everyday lives. If you are in regular contact and one of you becomes infected, everyone in that group will be vulnerable. However, if everyone follows the same rules it would allow the infected person(s) to inform the others as soon as possible so that they can self-isolate, thereby minimising the risk of transmission within your circle and also preventing it from spreading beyond that limited group. Can I become infected from a contaminated surface? Fears of catching the Coronavirus from contaminated surfaces have prompted many of us to wipe down groceries, leave our shoes outside, wash our clothes on the highest temperature setting, and stress about touching things such as elevator buttons, trolley handles, door knobs, ATMs and card machines. So exactly how high is the risk of contamination through fomite transmission? (That, by the way, is the scientific term for indirect transmission through contact with a contaminated surface.) It is referred to as indirect transmission as a whole chain of events need to occur in order for you to become
infected. It would have to start with someone who is infectious (though, as we all know by now, not necessarily symptomatic) transmitting a large enough amount of virions by coughing or sneezing on their hand (if not directly onto a surface) and then touching an object or surface such as a glass, a tin of baked beans, a door handle or a bathroom tap. Next thing, the virus would have to survive long enough until you come along and touch the contaminated surface and pick up enough viable virus on your hands, and then you touch your eyes, nose or mouth. Now, although studies have shown that the virus can last up to three days on hard surfaces such as steel and plastic and about 24 hours on cardboard and fibres, it starts to disintegrate within hours of landing on a surface, making it less viable (remember the “critical mass” needed to make you sick). All of which makes this scenario rather unlikely, especially if you are in the habit of washing your hands regularly. You cannot become infected through your skin, so this simple action, which should be second nature to us by now, will break the chain of events that could possibly lead to transmission. The bottom line is that, although there is some risk involved, fomite transmission is not the primary driver of COVID-19 infection. The disease is mainly spread from person to person through close physical contact, with the virus transmitted into the air by an infectious person and inhaled by another, straight into the upper respiratory tract. Because the virus decays beyond the point of being infectious when it hangs around outside a human body long enough, it’s people who pose the biggest risk – and not objects or surfaces. SOURCES: nytimes.com; immunopaedia.org.za; news-medical.net; discovermagazine.com; medium.com
