R-0 may be the most important scientific term you̵

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Officials were able to control the transmission rate of COVID-19 by applying policies that encourage residents to eat and drink, exercise, and spend time with friends and loved ones at a safe distance outdoors.

But medical experts are concerned that cases could jump again as colder temperatures in autumn and winter force people to return to the premises.

Leading national infectious disease expert Dr. Anthony Foci is also concerned about upcoming holidays that could increase transmission and advised Americans to skip any big Thanksgiving plans.

Speaking to CBS Evening News on Wednesday, Foci warned against “gathering together indoors” with large groups of guests outside the city. “It’s unfortunate because it’s such a sacred part of the American tradition – family gatherings around Thanksgiving. “,” he said. “But it’s a risk.”

Some experts suspect that the indoor transmission contributed to the summer outbreak of COVID-19 in the southern states, when residents retreated to air-conditioned public places to avoid the heat. According to John Hopkins, the three most populous states – California, Texas and Florida – raised more than 500,000 infections at the peak of the outbreak in August.

“Indoors in public places is one of the places where the risk and transmission of infection are most likely to occur,” said William Hanaj, an associate professor of epidemiology and a professor at the Center for the Dynamics of Infectious Diseases at Harvard School. Health care.

What makes collecting indoors so dangerous and how can you be safe?

Recommendations for updating the CDC (again): Notes the risk of airborne transmission, says coronavirus can infect people more than 6 feet away


On Wednesday, New York reached the brink of recovery, as for the first time since March, it was allowed to eat in indoor restaurants. (April 30)

AP Internal

“Minor infections lead to most infections”

Dr. Lewis Nelson, a professor and head of the Department of Emergency Medicine at Rutgers Medical School in New Jersey, said one of the main reasons why there is a greater risk of transmission indoors than outdoors is the lack of ventilation.

Natural air currents disperse the virus particles faster and more efficiently than inside. Indoors, there is minimal or no air circulation, which allows the virus particles to linger in the air or get on surfaces that have a high contact.

“If I smoked a cigarette (inside), you would see the smoke particles linger,” he said. “While the smoke stays outdoors.”

In addition, there are more surfaces in closed public places. When breath drops or aerosol particles fall, they fall on the table tops of chairs, stools, doorknobs and other objects that people often touch.

“There’s less surface in the open,” Nelson said. “No one touches the ground and then touches the eyes, nose or mouth.”

People are also usually closer to the room because they are limited by walls. Hanaj said bars are a major source of transmission in communities because people tend to gather there for long periods of time as alcohol consumption deteriorates.

According to the US Centers for Disease Control and Prevention, adults with confirmed COVID-19 were twice as likely to dine at a restaurant 14 days before they fell ill than those who tested negative.

Positive patients were also more likely to report visiting a bar or coffee shop when the analysis was limited to those who did not have close contact with people known to have the coronavirus.

“A minority of infections lead to most infections,” he said. “Obviously, if you’re in a bar, this group is usually much bigger because more and more people are coming together.”

How to increase air flow and ventilation in the room

Experts agree that increasing the flow of air in the room is important to reduce the risk of transmission, as it prevents the virus particles from hanging for too long.

Ventilation rate is the amount of outside air supplied per unit time and the rate of air changeis the rate of ventilation of a space divided by the volume of that space, according to Shelley Miller, a professor of mechanics at the University of Colorado Boulder.

Most air conditioning and heating systems circulate about 20% of the fresh air in a building, while recirculating the remaining 80% or so for energy efficiency.

However, ventilation can be increased by opening the window and turning on the fan. Most portable air filters cannot filter airborne virus particles, but they still promote the circulation of air that disperses the virus. HEPA-filtered air cleaners remove more than 99 percent of airborne particles, regardless of particle size, and facilitate air circulation.

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“If you can quickly clean up any airborne virus, you’ll reduce the risk of transmission,” Miller said.

Although UVC devices are useful for commercial buildings such as offices and schools, experts recommend sticking to a simple fan or portable air filter for residential areas, as some disinfectants can be harmful if used incorrectly.

Another good way to reduce the risk of transmission is to limit the number of people in the room, which contributes to better indoor air quality in general.

“If I reduce the number of students from 35 to 17 now, ventilation provides twice as much outside air per person, and that’s great,” Miller said.

BranchPattern’s construction consultant has developed an online calculator that determines transmission risk by entering space characteristics such as heating, ventilation, number of people in the room and how long. The user can also add settings such as wearing a mask and portable filters.

Return to basics: masks, social distance and hand hygiene

Experts say that the best way to protect yourself indoors is through three main mitigation efforts: masks, social distancing, and hand hygiene.

“Taking all these things together and putting them into practice, we hope, should slow down the pace,” Hanaj said.

Masks are especially important. CDC Director Robert R. Redfield told the Senate committee in mid-September that the vaccine may not be available to the American public until the summer or fall of 2021, and that masks are “the most important, most powerful health tool in our country” – perhaps even more effective. than the vaccine.

Dr. Sunil Sud, an infectious disease specialist at Southwell Health University Hospital in Bay Shore, New York, said canteens should wear masks even when eating outdoors.

“It’s boring … (but) you just have to do it,” he said. “The only time you need to take off your mask is when you’re actually biting and chewing.”


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This means holding the mask while talking to other visitors, waiting for food and talking to the waiter.

Dr. Chad Asplund, a professor of family medicine and orthopedics at the Mayo Clinic, said the rules also apply to the gym.

He recommends constantly wearing a mask, wiping cars and washing your hands. He also does not recommend the use of some gyms, such as yoga mats and blocks.

“If you do intervals, it’s harder to wear a mask,” Asplund said. “You may want to be creative with the time you usually go, because there are definitely times (when it’s getting crowded) before and after work.”

For social distancing, the Colorado Department of Health has developed an online tool that calculates transmission risk using the total area of ​​space and objects in a room to determine how many people can be safely there at one time.

Monitor community data rates

Although wearing masks, social distancing, hand hygiene, and increased airflow can reduce the risk of indoor transmission, these mitigation efforts are not 100% effective, especially if the transmission rate in the community is high.

Barry Bloom, a research professor of health and former dean of the Harvard School of Public Health, advises residents to monitor the transmission rate in their area to determine whether it is safe to visit an indoor public facility.

“When (rates) are high, as in many parts of the state, it’s just a matter of trouble,” he said.

There are many more questions about COVID: Is 6 feet really a safe distance? Is it worth going to a bar?

Super distribution events: How do they cause COVID-19 outbreaks and is the White House a hot spot right now?

Bloom says this is happening in the UK, where the number of confirmed cases of COVID-19 has more than tripled in the last three weeks, with the level of infection rising in all age groups and regions.

British Prime Minister Boris Johnson on Monday unveiled a new system that gradually tightened measures to slow the spread of the virus, three weeks after a nationwide program banning more than six people and demanding the early closure of pubs and restaurants.

“It makes a big difference whether you’re in a low gear or in a high gear environment, how flexible you are to stay safe,” Bloom said.

Contributed by: Ramon Padilla, USA TODAY; Associated Press. Follow Adriana Rodriguez on Twitter: @AdriannaUSAT.

Coverage of patient health and safety in the United States TODAY has been made possible in part by a grant from the Massimo Foundation for Health Ethics, Innovation, and Competition. The Massimo Foundation does not provide editorial materials.

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