Virus infection advice disappears from CDC website

On Monday, a few days after announcing important new guidance on aerial transmission of the coronavirus, the Centers for Disease Control and Prevention simply said it was “incorrectly posted” on the authorities’ website and withdrew its advice.

As President Trump and his senior health officials tried to hurt CDC scientists, the rapid reversal sparked surprises among scientists and again questioned the credibility of the world’s best health institutions.

The president will face elections, which could result in increased public awareness of the coronavirus pandemic response.

A change of direction took place as the number of virus-related deaths in the United States approached 200,000. With tens of thousands of new infections reported daily, experts fear a resurgence as cool weather approaches and people spend more time indoors.

For the first time, the new document acknowledged that the virus spreads primarily in the air. This is a declaration of urgent implications for how people protect themselves indoors and how ventilation is designed in schools, offices, hospitals, and other public buildings.

A case-savvy expert said on Monday that the latest reversal appeared to be a real mistake in the institution’s scientific review process, not as a result of political interference. Authorities said they would soon release revised guidance.

“We are rigorously reviewing the process and standards to see all guidance and updates before they are posted on the CDC website,” said agency spokeswoman Jason McDonald.

Still, this reversal prompted even the strongest supporters of the CDC to blame. “It doesn’t give you a lot of confidence, right?” Said Dr. Carlos Del Rio, an infectious disease expert at Emory University. “It doesn’t help at all.”

Other scientists find it difficult to understand that such a document of public health importance may have been posted without careful scrutiny of how closely the authorities’ actions are currently being scrutinized. Said.

“At this point, we all know that the problems of scientific communication are very high,” said Dr. Abraar Karan, a physician at Harvard Medical School.

The expansion of the pandemic in the United States has hit the CDC in a series of blows. For example, only in April, after saying that a mask was not needed, authorities recommended a public face cover.

The CDC said in August that people who are in close contact with infected people but have no symptoms do not need to be tested for infection. But last week, later The New York Times reported The agency reversed its position that the guidance was determined by the authorities, not by scientists, saying that all close contact with infected people should be examined regardless of symptoms.

The reversal was “to focus on his health and family well-being,” after HHS top spokesman Michael R. Capto accused federal scientists of “sedating” in a strange Facebook rant. It happened after I took a vacation. Dr. Paul Alexander, an adviser to Caputo, who was very critical of the CDC’s work, will also drop out.

Mr. Trump blamed Director Robert Redfield after a government hearing last week that Dr. Redfield said at a parliamentary hearing that the vaccine would not be widely available until mid-next year. “It’s just inaccurate information,” the president said.

With constant controversy, “it’s much more difficult for the general public to see this guidance and wonder,’what the hell does this mean?'” Dr. Karan said. It was.

The latest incidents are related to the spread of the virus by air through droplets and aerosols. It is a small particle containing a virus that can stay in the air for long periods of time and travel more than 6 feet.

From the beginning of the pandemic, scientists knew that respiratory droplets from infected people sneezing and coughing could spread the coronavirus. More recently, health organizations such as the World Health Organization have recognized the role of floating aerosols expelled by speaking, breathing, and singing.

Both new CDC documents have described them as aerial transmissions, but authorities have not previously detailed the broad role of aerosols.

The virus spreads through “droplets such as aerosols or respiratory drops that occur when an infected person coughs, sneezes, sings, talks, or breathes,” the CDC announced Friday and then withdrew. Said it was done.

Authorities added that these particles could be inhaled and cause infections: “This is believed to be the main way the virus spreads.”

“Aerial viruses, including Covid-19, are the most contagious and easy to spread,” said Saskia Popescu, a hospital epidemiologist at George Coson University.

The virus in the air requires the patient to be quarantined in a so-called negative pressure chamber, preventing the virus from escaping, and healthcare professionals should always wear an N95 mask.

“The challenge then is that not all patients can be placed in the negative pressure chamber,” said Dr. Popescu.

She added that if the hospital’s ventilation and infection control systems were inadequately protected against the virus, the hospital would spread more infections.

“My gut tells me why they really pulled it,” said Dr. Popesque. “I think they understand that” air “cannot be thrown away unplanned. It has very serious consequences for hospitals. “

According to previous scientific studies, aerosols are primarily important in certain situations and are used in poorly ventilated and crowded rooms such as most bars, clubs, gyms and restaurants.

In these spaces, the virus floats in the air for extended periods of time and can travel more than six feet, officials warned in a document posted Friday.

At the beginning of this summer, scientists Isolated living virus From aerosols collected at distances of 7 and 16 feet from infected patients in hospitals. Aircraft proliferation could explain many so-called “superspreader” events, scientists say, clusters of cases, etc. After chorus practice in WashingtonAnd why the southern states saw a surge in infections this summer when people stayed indoors in an air-conditioned environment.

Researchers noticed on Sunday that the agency updated the description of how the virus is transmitted because the pathogen is spread primarily by air. Many welcomed the CDC’s recognition of these risks and the approval of air filters in indoor spaces.

“Many people spend hours cleaning the place, and frankly, I think it’s pretty overkill,” said Dr. Del Rio.

However, the new language disappeared on Monday morning, and official advice returned to the previous explanation of the spread by respiratory droplets. “The draft proposed changes to these recommendations were mistakenly posted on the agency’s official website,” the agency said.

This document will be posted “prematurely” on the CDC website and will be published after revision, according to federal authorities familiar with the matter.

More than 200 experts studying aerosols called on the World Health Organization in July Review evidence for aerosol propagation Coronavirus

WHO Admitted that this route seems to make a big contribution For the pandemic epidemic, but experts disagree about its importance compared to the heavier respiratory droplets that sneeze and cough depending on the infected patient.

“Currently, there isn’t one more epidemiological evidence than the others,” said Dr. Popescu.

Some experts have said which is more important-whether droplets or aerosols-is important how people should protect themselves.

“Aerosols are very important and I think public health guidance is important enough to place them in front and in the center,” said Lindsey Marr, an aerial virus expert at Virginia Tech. .. “I hope it comes back in some way that recognizes the importance of aerosols.”