“We are making surprises all the way,” said Dr. Conly. “I find this work interesting, but there is a long way to go to reach a line of credibility, in my mind.”
Dr. George Rutherford, professor of epidemiology at the University of California, San Francisco, was just as skeptical. He said that outside the hospital, “the big points in my mind make up the vast majority of cases. Aerosol transmission – if you are really dealing with it, it creates a lot of dissonance. Are there situations when this can happen? “Yes, but it is a small amount.”
Dr. Tang and other scientists strongly disagree. “If I̵7;m talking to an infectious person for 15 or 20 minutes and inhaling a little of their air,” said Dr. Tang, “is not a much simpler way to explain the transmission than touching an infected surface and touching your eyes? When you are talking about an explosion, like in a restaurant, the latter seems like a torturous way to explain the transmission. “
Frequently Asked Questions
Updated July 27, 2020
Do I have to refinance my mortgage?
- It might have been a good idea because mortgage rates have never been lower. Refinancing applications have pushed mortgage applications to some of the highest levels since 2008, so be prepared to go online. But the defaults are also high, so if you are considering buying a home, be aware that some lenders have tightened their standards.
What will the school look like in September?
- It is unlikely that many schools will return to a normal schedule this fall, seeking to continue online learning education, perfect child care and hectic workdays to continue. California’s two largest public school districts – Los Angeles and San Diego – said on July 13 that the guidelines would be remote only in the fall, citing concerns that coronavirus infections in their areas pose a very high risk to students and teachers. Together, the two districts enroll about 825,000 students. They are the largest in the country so far to abandon plans for even a partial physical return to the classrooms when they reopen in August. For other districts, the solution will not be an all or nothing approach. Many systems, including the largest city, New York City, are designing hybrid plans that include spending a few days in class and other days online. There is still no national policy on this, so check your municipal school system regularly to see what is happening in your community.
Is air coronavirus?
- The coronavirus can stay up for hours in small droplets in stagnant air, infecting people as they inhale, scientific evidence suggests. This risk is highest in the enclosed spaces of poorly ventilated homes and may help explain the super prevalent reported events in plants, few churches and restaurants. It is unclear how often the virus has spread through these tiny droplets, or aerosols, compared to the larger droplets that are expelled when a sick person coughs or sneezes, or is transmitted through contact with contaminated surfaces, said Linsey Marr, an expert of aerosol at Virginia Tech. Aerosols are also released when a person without symptoms digs, talks or sings, according to Dr. I also get more than 200 other experts who have described the evidence in an open letter to the World Health Organization.
What are the symptoms of coronavirus?
Does asymptomatic transmission of Covid-19 occur?
- So far, the evidence seems to show that it does. A widely cited paper published in April suggests that people are more infectious about two days before the onset of coronavirus symptoms and estimated that 44 percent of new infections were the result of transmission from people who did not yet show symptoms. Recently, a senior expert at the World Health Organization stated that transmission of the coronavirus from people who had no symptoms was “very rare”, but it was later withdrawn again.
In the new analysis, a team led by Parham Azimi, an indoor air researcher at Harvard’s TH Chan School of Public Health, studied the explosion at Princess Diamond, where physical spaces and infections were well documented. He conducted more than 20,000 simulations of how the virus could have spread across the spacecraft. Each simulation made a variety of assumptions, about factors such as patterns of social interaction – how much time people spent in their cabins, on deck or in the bar, on average – and the amount of time the virus could live on the surface. Each is also factorized into different contributions of small, floating points, broadly defined as 10 microns or less; and larger droplets, which fall faster and infect surfaces or other people, lowering the eyes, mouth, or nose, they say.
About 130 of these simulations reproduced, to some extent, what actually happened to Princess Diamonds as the explosion progressed. By analyzing these more “realistic” scenarios, the research team calculates the most likely contributions of each transmission path. The researchers concluded that the smallest points prevailed and accounted for about 60 percent of new infections above all, both at close range, within a few yards of an infectious person, and at greater distances.
“A lot of people have argued that airborne transmission is happening, but no one had numbers for it,” said Dr. Azimi. “What is the contribution from these small points – is it 5 percent, or 90 percent? In this paper, we give the first true estimates of what that number might be, at least in the case of this cruise ship.”
The logic behind such a broadcast is simple, experts said. When a person speaks, he or she emits a cloud of dots, most of which are small enough to stay suspended in the air for minutes or longer. Through suffocation, that cloud of small droplets is more likely to reach a mucosa than the larger one that grows ballistically.