Although the risk of outdoor transmission may be low, it is not zero
After more than a year of pandemic life, many people are still confused about the risks of spending time outdoors with others. More and more studies have shown that the possibility of spreading Covid-19 outdoors is much lower than the possibility of spreading indoors, and as more people get vaccinated and cases continue to decrease, this risk will be lower . But many states have yet to abolish strict outdoor mask regulations. For example, in Massachusetts, even if there are no other people around, there is always a need for outdoor shelter.
Recently, the online magazine Slate caused controversy when it proposed to end the regulations on outdoor masks. This article was supported by leading public health experts and even the New England Journal of Medicine blog, but it drew a strong response from readers who pointed out that although the risk of outdoor transmission may be low, it is not zero.
A year later, many of us have learned to wear masks and ask those who do not wear masks. This is understandable. People still feel fear when they meet people who do not have masks. So, how do you correctly decide when to wear a mask outdoors?
Many virus and public health experts say that the guidelines have not changed-time spent with other people during a pandemic is always safer than being indoors. However, the need for outdoor masks depends on the situation, including local public health regulations. Linsey Marr, a professor of civil and environmental engineering at Virginia Tech, said that the risk of a brief encounter on a sidewalk or trail with a person who does not wear a mask is extremely low. The virus particles spread rapidly in the outdoor air, and there is a danger of inhalation. . He said that aerosol viruses from runners or bystanders are trivial. He said that even if a person coughs or sneezes outside while walking, the chance of receiving a sufficient dose of the virus is still very small.
Dr. Marr said: “I think the guidelines should be based on science and practicality.” People have limited bandwidth to consider preventive measures. I think we should focus on the areas that are easiest to spread, and let people rest when the risk is extremely low. “
Marr uses a simple two-thirds rule to decide when to wear a mask. In any case, he must ensure that two of the following three conditions are met: outdoor activities, independent work and masks. He said: “If you are outdoors, you must take off your clothes or put on a mask.” “If he is not outdoors, he must take off your clothes and put on a mask. This is my life last year. It all depends on my three points of two.”
When do I need to wear a mask outdoors?
If you stop having long conversations with people who have not been vaccinated, it is recommended to wear a mask. Even when outdoors, the risk of breathing other people’s air will get closer and closer as you get closer and closer to that person. One of the few recorded cases of outdoor transmission occurred in China at the beginning of the pandemic, when a 27-year-old man stopped to chat with a friend who had just returned from Wuhan. Seven days later, he developed the first symptoms of Covid-19.
If you find yourself in an outdoor crowd, it is still recommended to wear a mask. Standing side by side with strangers at outdoor concerts or protests can increase the risk, especially for people who have not been vaccinated.
When is the least risky being outdoors?
Activities Dogs, cycling, walking on trails, or going on a picnic with family or friends vaccinators are all activities where the risk of exposure to the virus can be ignored. In this case, if you find yourself crowded or need to enter the door, you can put a mask in your pocket.
Dr. Muge Cevik, clinical professor of infectious diseases and medical virology at the University of St Andrews School of Medicine, said: “I think it’s too much for people to wear masks when walking, jogging or cycling,” in Scotland. “We are at different stages of the pandemic. I think outdoor masks shouldn’t be mandatory at all. This is not a place where infections and spreads occur.”