How did a person infect the new coronavirus to 52 people in just two and a half hours?

According tomedia BGR, researchers a few weeks ago proposed the theory that just talking is enough to spew out virus-carrying droplets that can spread new coronaviruses. A growing number of models show how droplets spread through the air after coughing or sneezing, and when talking, while a recent model actually measures the amount of virus a person can emit when they speak loudly. These studies have also shown that in a closed space, air circulation may promote the spread of COVID-19 aerosols and may increase the risk of infection for others in the region. More studies have shown that viruses can survive for hours to days on certain surfaces, so when a person talks, sneezes or coughs, everything around them can be contaminated with droplets containing infectious virus particles.

All of these studies have shown that the use of masks is most important when there is a social distance, whether or not there is a blocking measure, especially when you have to get into the place where you will come into contact with others. In addition, it is recommended that you wash your hands as often as possible, especially after touching objects or surfaces that others have come into contact with, and pay more attention to hand washing them. But as early as early March to mid-March, we don’t have the data and don’t know how susceptible COVID-19 is. A new study shows that an asymptomatic choir member took a two-and-a-half-hour course, but infected 52 of his 61 colleagues with the new coronavirus, two of whom eventually died of COVID-19 complications.

How did a person infect the new coronavirus to 52 people in just two and a half hours?

The new study, published on its website by the U.S. Centers for Disease Control and Prevention (CDC), analyzed infections in the choir in Skagit County, Washington.

The study explains how things went. A member of the choir began to develop cold-like symptoms around 7 March. Three days later, the member took part in a two-and-a-half-hour exercise in the choir. Several members arrived early and placed chairs in six rows of 20 chairs, 6-10 inches apart. Since only 61 of the 122-person team took part in the exercise, some people sat separately with others during the exercise for 40 minutes.

They then divided into two groups for 50 minutes of practice. Each group moved to a smaller room, and the group of people who stayed in the larger room moved their seats to the side. The man in the small room sat on the bench next to him. They had a 15-minute break and then regrouped in their original seats for the last 45-minute joint exercise. At the end of the exercise, each member puthis his or her chair back in his or her seat and circles around the frame. No one reported physical contact between participants.

Participants began to develop symptoms within 1 to 12 days of practice. Of the 53 patients, 3 were hospitalized and two died about two weeks after the onset of the disease. The study noted that 19 of them were listed as suspected cases, but no tests were sought to confirm the condition. Notably, the Trump administration did not declare a state of emergency in the United States due to the new corona virus until March 13.

The study concludes that:

The possibility of super-transmitter events highlights the importance of physical distances, including avoiding large groups of aggregation to control the spread of COVID-19. Increased community awareness can encourage isolation or self-isolation of people with symptoms and contacts of the sick to prevent continued transmission…

The high recurrence rate of COVID-19 in this outbreak indicates that SARS-CoV-2 may be highly propagating in certain situations, including group singing activities. This highlights the importance of keeping the body at arm’s length during the outbreak, including keeping people at least 6 feet away, avoiding group gatherings and crowded places, and wearing cloth masks in public.

Speaking is enough to make droplets spread in the air, let alone sing. Touching the same surface is also considered a risk factor.

Participants in the choral exercise had several opportunities to spread the droplets in close contact, and the singing act itself could lead to SARS-CoV-2 transmission. The release of aerosols during speeches is associated with the loudness of the sound, and some people release an order of magnitude more particles than their peers, known as supertransmitters, and are also presumed to be contributing factors to ultrasound events. Members make long contacts and sing songs 6-10 inches away from each other, possibly releasing aerosols.