The risk of infection is particularly high when minute infectious droplets (aerosols) accumulate indoors. Researchers have calculated that the risk of infection is 19 times higher indoors than outdoors. The smaller the room, the longer a person stays in it and the more viruses an infected person currently emits, the easier it is to become infected.
At the workplace
If an infectious colleague is sitting in the room with you, the risk of infection is high – simply because you spend many hours together. If employees wear masks and ventilate regularly, and the room is large and high, this reduces the risk of infection. Air conditioners with filters that trap the virus also significantly reduce the risk. However, air conditioners that only circulate the air unfiltered actually increase the risk of infection.
In fact, the risk of infection is even higher in workplaces where physical labor is involved: where there is more sweat, there are also more aerosols.
How to protect yourself: Even if you miss your colleagues – work in a home office if possible. Otherwise, ventilate regularly and wear a mask if possible. Also, accept offers for regular testing.
Outdoors
The risk of infection is higher when there is no wind, because an aerosol cloud then easily forms around infectious persons. Those who move around outdoors, on the other hand, have only a very low risk of infection.
Here’s how to protect yourself: Keep moving. If you are sitting outside in a restaurant, choose a table that is not downwind of another table, if possible.
At home.
Most traceable infections occur in contact with members of your own household. This is not surprising: people spend a lot of time together and generally do not keep their distance from each other. Anyone who also shares a bed with an infected person is naturally at particular risk.
This is how you protect yourself: Adhering to hygiene rules within a family or partnership, or even in a shared apartment with friends, is unrealistic. You should therefore all take care not to become infected outside your own four walls.
In the elevator
Modern elevators are usually well ventilated and therefore offer only a low risk of infection. Older models are a different story. Aerosols accumulate particularly quickly in the narrow cabs – and because the doors only open briefly, they remain airborne for a long time. Even those who ride alone in an elevator can become infected if an infected person has ridden in the elevator before.
In the gym
There is also an increased risk of infection in fitness studios. Hygiene rules are not always observed in the heat of the moment. Most importantly, the physical exertion causes exercisers to exhale more aerosols. In calmer classes such as yoga, on the other hand, the risk of infection is lower.
Here’s how to protect yourself: if possible, plan your visit to the gym outside of peak hours and observe hygiene rules such as wearing a mask on the way to the equipment.
In bars and clubs
Bars and clubs in Germany are still closed. But when they reopen, the risk of infection is likely to be comparatively high: Keeping a distance is difficult, the noise level requires loud talking with corresponding aerosol emission. And when there is boisterous dancing, heavy breathing adds to the risk.
In the supermarket and other stores
In supermarkets, the time spent is comparatively short, and the premises are large. In addition, it is compulsory to wear FFP2 masks. Therefore, the risk of infection is rather low here. The same applies to other larger stores.
How to protect yourself: make sure the mask fits snugly over your face. If possible, schedule your shopping outside of peak hours. Also, if you plan your purchases ahead, you can reduce the number of times you visit the store.
During a conversation
If you are talking to someone, you should wear a mask to protect yourself and the person you are talking to, or keep at least two meters away.
This is how you protect yourself: currently, keep conversations as brief as possible, keep your distance and, if possible, turn away from the person you are talking to a little when speaking. In times of Corona, other laws of politeness apply!
About objects
If fresh virus-containing secretion sticks to an object, it is theoretically possible to become infected in this way. As soon as one subsequently touches the mouth, nose or eyes with contaminated hands, the virus can enter the body via the mucous membranes. In particular, heavily frequented objects such as door handles, bus handholds, elevator control buttons and the like therefore pose a certain risk.
The same theoretically applies to merchandise deliveries or the ballpoint pen lying around. Studies suggest that the virus can survive on objects for several hours or days, depending on the surface, temperature and humidity. Under laboratory conditions, the viruses last three to nine days on steel and plastic. On cardboard and paper, on the other hand, the virus survived for only up to 24 hours.
Conclusion: In principle, experts consider the risk of infection via objects that have not been immediately and massively contaminated to be extremely low. So far, no case has been reported in which a person was infected via an object that had been contaminated for a long time.
How to protect yourself: Thorough hand washing is the main way to protect yourself from contact infection. Make it a habit to wash your hands thoroughly with soap or alternatively with a disinfectant whenever you have the opportunity and whenever you come home.
Also, avoid touching your face with unwashed hands, especially around your mouth, nose and eyes.
About food
The same applies to food as to objects: If an infected person has coughed or sneezed on it, and a healthy person consumes it shortly thereafter, infection could be possible.
However, sufficient viruses must be ingested – which is hardly possible if, for example, an infected person has only briefly picked up an apple. In fact, infection via contaminated food has not yet been proven.
How to protect yourself: The German Federal Ministry of Food and Agriculture advises that food should be washed thoroughly before preparation, if possible, to reduce the risk of infection.
When jogging or walking
How to protect yourself: So even outdoors – keep your distance and stay as little as possible. If that is not possible, wear a mask.
In public transport
Public transport is problematic because at peak times there is hardly any opportunity to keep a safe distance. However, the risk of contracting a droplet infection here is comparatively low because masks are compulsory. Thanks to the mostly short duration of stay (15 minutes on average), aerosol exposure is also not serious. However, it is theoretically possible to become infected through freshly contaminated handles or door openers.
Here’s how to protect yourself: avoid peak hours if possible. Make sure your FFP2 mask fits snugly over your face. Avoid touching your face and wash your hands thoroughly after traveling (alternatively, use hand sanitizer).
On air travel
Air travelers are now required to show proof of vaccination or a negative test result before boarding. However, these do not offer 100 percent protection. However, modern, large airplanes are well ventilated and equipped with Hep filter systems that filter viruses from the air. The risk of contracting the virus during the flight comes mainly from the people directly next to you.
On train travel
How safe it is to travel on trains is currently unclear. According to one study, train attendants are no more likely to become infected with Corona than railroad employees without customer contact. However, these results can only be applied to passengers to a limited extent. After all, train attendants do not sometimes sit for hours next to the same potentially infected person.
But vertical ventilation and wearing masks can significantly reduce the risk of infection for train passengers. Researchers at the Technical University of Berlin have calculated that a three-hour train journey with a mask and at half capacity carries about one and a half times the risk of infection of a visit to the supermarket (and this is already very low). One thing is certain: the closer and the longer you sit to an infected person, the higher the risk of infection.
How to protect yourself: If possible, choose train connections that are less busy. Consistently wear an FFP2 mask and make sure it fits properly. Disinfect your hands after opening train doors or using grab bars.
Long-distance bus travel
Here’s how to protect yourself: choose low-occupancy rides when possible and make sure your mask fits properly.
Cinemas and theaters
According to experts at the Technical University of Berlin, visits to theaters and cinemas are quite safe under certain conditions. According to the study, a visit with 30 percent occupancy, provided everyone wears a mask, is only half as risky, for example, as shopping with a mask in the supermarket, which is also not too risky.
Here’s how to protect yourself: wear your mask and sit as far away from fellow spectators as possible.
About pets
Cats can contract Sars-CoV-2 and become ill. So far, however, these appear to be isolated cases. The virus has also been detected in dogs, but they do not develop any symptoms.
For both of the Germans’ favorite animals, it is true that they can become infected in humans – but this does not happen the other way around.
Farm animals such as pigs and chickens are not infected with the new coronavirus, according to an investigation by the Friedrich Loeffler Institute. So there is no danger from them. Ferrets and fruit bats, on the other hand, are susceptible to the virus.
