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How to organize a meeting of less than 50 people indoors?

Text updated on 2020-09-05

Do you want to organize a one-off meeting with less than 50 people indoors and avoid COVID contamination ? Here are our tips.

1. Choose the right room and time for the meeting.

2. Recommendations to be provided to invitees prior to the meeting

3. At the meeting

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A good synthesis on the aerial transmission of the SARS-CoV-2, published in June 2020, strongly advises to wear masks on the basis of scientific arguments. The authors also propose an analogy between the diffusion of cigarette smoke and that of viral aerosols.

Prather, K. A., Wang, C. C., & Schooley, R. T. (2020). Reducing transmission of SARS-CoV-2. Science.

The analysis of 318 cases where one person contaminated at least 2 other people in China (for a total of 1,245 people with COVID-19) reveals that the majority of the contaminations took place in a closed space, mainly house and transport, but also in restaurants, and that only one contamination took place following an open air conversation with a person returning from Wuhan.

Qian, H., Miao, T., Li, L. I. U., Zheng, X., Luo, D., & Li, Y. (2020). Indoor transmission of SARS-CoV-2. medRxiv.

In Japan, many cases of "cluster" contamination have occurred in closed places: a sports hall, restaurant boat, hospital, festival where there were tents with minimal ventilation for eating.

Nishiura, H., Oshitani, H., Kobayashi, T., Saito, T., Sunagawa, T., Matsui, T., ... & Suzuki, M. (2020). Closed environments facilitate secondary transmission of coronavirus disease 2019 (COVID-19). medRxiv.

One person became infected by going on a bus that had been used by an individual with COVID-19 when they had left the bus 30 minutes earlier.

Chen, S. (2020) Coronavirus can travel twice as far as official 'safe distance' and stay in air for 30 minutes, Chinese study finds. South China Morning Post. 9 March 2020.

In January-February 2020 in Guangzhou, China, a person was infected by entering an elevator in which an individual, who later tested positive for the SARS-CoV-2 coronavirus, had entered two minutes before. Neither person was wearing a mask and they both pressed the same elevator button. It is not known whether the contamination was indirect through contact with the elevator button or through the inhalation of aerosols.

Xie, C., Zhao, H., Li, K., Zhang, Z., Lu, X., Peng, H., ... & Gu, Y. (2020). The evidence of indirect transmission of SARS-CoV-2 reported in Guangzhou, China. BMC public health, 20(1), 1-9.

On a flight from Italy to South Korea, a 28-year-old was infected when she took off her mask to go to the bathroom. Of the 299 passengers on that flight, 6 asymptomatic people later tested positive for the SARS-CoV-2 coronavirus and one of them had used the same bathroom. The 18 cabin crew and medical personnel were not contaminated. They all wore masks.

Bae, S. H., Shin, H., Koo, H. Y., Lee, S. W., Yang, J. M., & Yon, D. K. Asymptomatic Transmission of SARS-CoV-2 on Evacuation Flight. Emerging infectious diseases, 26(11).

A man who had put his mask on incorrectly was contaminated during a flight from Singapore to Hangzhou, China on January 24, 2020. On the plane, he sat with his mask in the wrong position for an hour next to two asymptomatic people who then tested positive for SARS-CoV-2 coronavirus, because he talked to his wife and child who were next to him. The other people sitting next to the infected people were not infected. They all wore masks.

Chen, J., He, H., Cheng, W., Liu, Y., Sun, Z., Chai, C., ... & Shi, X. (2020). Potential transmission of SARS-CoV-2 on a flight from Singapore to Hanghzou, China: An epidemiological investigation. Travel Medicine and Infectious Disease, 101816.

Study of 961 patients with COVID-19 in Hong Kong between December 2019 and April 2020 and the cause of their contamination. Non-masked" leisure activities, such as eating and drinking in restaurants and bars, singing in a karaoke bar, or playing sports in a gym, led to significantly more cases of contamination than "masked" work environments.

Cheng, V. C., Wong, S. C., Chuang, V. W., So, S. Y., Chen, J. H., Sridhar, S., ... & Yuen, K. Y. (2020). The role of community-wide wearing of face mask for control of coronavirus disease 2019 (COVID-19) epidemic due to SARS-CoV-2. Journal of Infection.

The rate of particle emissions increases with the volume of the voice.

Asadi, S., Wexler, A. S., Cappa, C. D., Barreda, S., Bouvier, N. M., & Ristenpart, W. D. (2019). Aerosol emission and superemission during human speech increase with voice loudness. Scientific reports, 9(1), 1-10.

Further reading

How does she get COVID-19 ?

Do I have to wear a mask if I don't have any symptoms?

What is the purpose of social distancing?