Either we pass, or we do not arrive. Either we disdain the risk of becoming ill due to poor hygiene at home -a third of food poisoning is generated at home, for being a little bitch handling food-, or we try to achieve an impossible asepsis by disinfecting every corner as if we were hiding the traces of a crime.
Of course, the context has changed: we are in the midst of a pandemic and we have all our senses on alert, trying to be aware of each movement and wondering if we made a mistake on our way out to make the purchase that could pose a risk. There is nothing more terrifying than the everyday turned into a threat, and to think that a tomato can, a package of pasta, a bottle of oil or a lettuce can get the virus at home is directly from a Dario Argento movie.
Coinciding with the coronavirus crisis, visits to the National Institute of Toxicology have increased by 17%, and 15% of the calls were for poisoning from using bleach and other surface disinfectants. We do not know if these surfaces were from products purchased during food outings, but we do know that in a quarter of the cases, lye had been mixed with ammonia, salfumán, vinegar, alcohol, anti-limescale, household cleaners or dishwashers.
Today we will try to answer all the doubts about what and how to disinfect, and above all what we should use to do it and what not; Because when we get creative there is no one to beat us and, if two products disinfect, their mixture disinfects twice as much. 1 + 1 = 2, from Zeus' lifetime. As those who have needed toxicological help have verified, in chemistry this rule is not followed.
ARE THE PURCHASE CONTAINERS A TROY HORSE?
I remember it once again: the main route of transmission is person to person. So constant handwashing, respiratory hygiene -you sneeze at your elbow, come on- and social distance, avoiding crowds and keeping a distance of one to two meters should be our main concerns (our partner Gemma del Caño already explained perfectly how to avoid risks in purchases).
But it is almost inevitable to get home and look at the bags suspiciously, as if you were opening the door to an invisible enemy and letting him into the kitchen (literally). I insist: it is very unlikely that you can get it through food packaging (as the WHO, the FDA and the US Center for Disease Control (CDC) remind us).
The health authorities have not made specific recommendations on the washing and disinfection of the containers - yes on other aspects, such as hygiene guidelines when arriving from the street - but if you want to apply the precautionary principle, you can take some extra measures:
- Wash your hands all the time (this is not an extraordinary measure, but a mantra that I will repeat to the point of exhaustion).
- If the containers are wrapped in cardboard or plastic, remove them from that packaging and throw it away.
- You can disinfect plastic and glass cans and containers with a cloth with diluted bleach - you know, two tablespoons of bleach for every 980 ml of water - or with alcohol of at least 70º. And clarify them, that I am already seeing you drinking your beer right afterwards (and uploading the statistics of calls to the Institute of Toxicology).
- Resign yourself: there are containers that you will not be able to disinfect. There is no way to sanitize paper or cardboard packaging without spoiling or risking part of the disinfectant coming into contact with food. But do not obsess: I insist that the risk of getting it through the packaging is very, very small.
- Wash your hands when you're done (did you think I wasn't going to repeat it to you?).
CAN FOOD SPREAD ME?
The WHO and the Ministry of Health remind us that transmission is person to person through the drops that we emit when coughing, sneezing or exhaling. Furthermore, the German Risk Management Agency indicates that there is no evidence of contagion by any other means, either by contact with surfaces or by food consumption.
That is the evidence available so far: the main reference organisms have not found that food is a source or a route of transmission of the coronavirus.
This has been stated by the European Food Safety Authority (EFSA). A position in which other entities like the Australian and New Zealand Food Standards Agency, the Irish Food Safety Authority (FSIA) or the US Food and Drug Administration (FDA) coincide.
It is not by chance: the strict hygiene standards that are applied in all the links of the food chain protect us from food poisoning and are also a barrier to prevent food from being contaminated by this virus.
Could you become infected if a person sneezed on food, touched it a short time later, dragged a quantity of virus high enough to cause the infection - this is what is known as "infective dose" - and put your hands to your mouth, eyes or nose? It's unlikely. Impossible? We do not know (although, I repeat, there is no evidence of any case in which this was the route of transmission). But it is avoided by scrupulously respecting the rules of food handling (in industries and supermarkets they already do it, you will not fail at the last link in the chain), and personal hygiene.
If you want to know more about food hygiene in times of coronavirus, you can download this infographic prepared by the Food Technologist and Disseminator Mario Sánchez, in which the Doctor in Food Science and Technology Miguel Ángel Lurueña and I have collaborated. In addition, you will also protect yourself from catching an intoxication, which is not sanitary so that we go to occupy beds due to salmonellosis.
HOW SHOULD YOU CLEAN THE KITCHEN AND OTHER SURFACES?
I will never, never, ever reveal who I mean, but I know of one case - my mother - who was disinfecting surfaces with half a liter of bleach for every half liter of water. 50/50 ratio: If you wonder why there was no bleach in the supermarket, mystery solved.
The fear of not disinfecting enough and that the virus can survive has led us to make strange mixtures, use disinfectants in very high concentrations or make our own homemade biocides with vinegar or bicarbonate. Bad everything.
First thing: the effect is not cumulative and by increasing the amount we will not have a better result. In addition, there may be products that manage to destroy some microorganisms, but which are not effective against the coronavirus. Have you checked it before you start scrubbing the tiles like there's no tomorrow? In addition, there can be potentially very serious health risks: mixing bleach with ammonia generates toxic gases and salfumán is highly corrosive. Not to mention that the floors or the counter can be left as if you had set them on fire.
Fortunately, you don't have to do experiments at home: there are already those who are in charge of investigating which compounds can safely destroy the virus. The truth, I trust more than the competent bodies and the scientific community say than the recommendations of an influencer, the guasap of the group of parents or a website of natural products against Covid-19. Something good had to have the bug: it destroys itself relatively well.
So let's follow the directions from the WHO, the European Center for Disease Prevention and Control (ECDC), the Ministry of Health, or the CDC:
Surfaces
- First step: clean. It is not synonymous with disinfecting, but a mandatory prior stage. It consists of removing visible dirt and is achieved with soap and water. Particular attention should be paid to door knobs, windows and cabinets, railings, switches, telephones, remote controls, surfaces of household appliances and furniture of constant use, taps, kitchen utensils ...
- Second step: disinfect. Yes, here we already destroy the virus (and other microorganisms that we may have around the house and that we now care less about). We will do it in the bathroom and on the surfaces that are touched most often. Various effective products can be used: Bleach: 20 ml (two tablespoons) in 980 ml of cold water. You have to prepare it just before cleaning. Let it work for five minutes and rinse it out next. Alcohol with a minimum concentration of 70%: the same as bleach, five minutes of action, followed by rinsing. Other authorized virucidal products: the Ministry of Health has a complete list, in which, in addition, you can also find effective products suitable for personal hygiene: always read the labels to ensure that you use them well.
Clothes and everyday objects
- Wash your hands before and after handling dirty clothes and objects.
- Do not shake dirty clothes and check the label of the clothes to use the washing program with the highest temperature that supports.
- Electronic objects can be delicate. Check the manufacturer's instructions and, if this is not possible, use alcoholic solutions that contain at least 70% alcohol.
Fabrics
If you have decided that it is a good time to do general cleaning and you want to put a scouring pad in your hand with carpets, upholstery or rugs, you can clean them with the usual products and, if you can wash them in the washing machine, do it at the maximum temperature that they support.
Please do not even think about following the enlightened advice of sources of dubious rigor that tell you that vinegar, lemon, alcoholic beverages or salt are "natural disinfectants": they are not effective against the coronavirus, neither on surfaces nor in food. .
We are in a very difficult time, yes. The reference organizations do not have all the answers and the recommendations are changing and (have I already told you that the virus is new and that we are learning everything on the go?), But I assure you that they are the ones that have the most of information of the highest possible quality: Let's not make it worse by applying imaginative solutions that are not endorsed by science or endorsed by any health authority.
Suspicious surfaces
How long can the viable virus remain on a surface? We do not know. It is the first time we have faced him and we are learning everything on the go. We are not totally blind, but we have no certainties.
One way to try to find out is to study the persistence of other human and animal coronaviruses similar to SARS-CoV-2, but already known and studied (such as the SARS-CoV that sparked the epidemic in 2002 or the MERS-CoV detected in 2012). This is what a review recently published in the Journal of Hospital Infection has done that, analyzing the time that coronaviruses remain viable on different surfaces -steel, aluminum, metal, wood, paper, glass, plastic, ceramic, etc.- and at different temperatures has found a wide variability: from one hour to nine days. But, I insist, it is not a specific study on Covid-19: it may serve to have some starting data, but it does not give certainty.
An investigation has also been published in the New England Journal of Medicine in which it has been analyzed in the laboratory how much our specific coronavirus "endures" in various materials. And yes, the type of material affects it: in copper it only lasts four hours, in cardboard it lasts a day and in plastic or stainless steel up to three days. But be careful, because the Ministry of Health also reminds us that these studies are carried out under controlled conditions of temperature and humidity, which are not necessarily extrapolated to real life.
In addition, this study also found that it could remain in aerosols (that is, "floating" in the air) for up to three hours, it has been interpreted that we could also be infected through the air (for example, taking an elevator in which someone would have sneezed). As if we didn't have enough. Not so fast. Several letters in response to the editor of the magazine, as well as the World Health Organization itself, stress that the aerosols were generated in experimental conditions, with high-powered equipment that does not reflect what happens when a patient coughs. At the moment (and I stress, for the moment) this transmission route is not clear.
Beatriz Robles is a food technologist, dietitian-nutritionist and obsessed with battling disinformation. Professor in the Degree of Human Nutrition and Dietetics at the Isabel I University and scientific disseminator. He has the book Eat safe eating everything in the oven, waiting for the coronavirus to allow him to put it up for sale.