I'm concerned about your last sentence so let me throw this question out to you. There has been discussion about where this virus got its start. There has been mention of a wet market, but it's also been mentioned that the Chinese have a medical facility in the area that focuses on viruses. Since the Chinese haven't been very forthcoming with information or willing to accept help, do you believe they have something to hide?
First U.S. case of unknown origin / "community spread" in Solano County, CA: https://www.google.com/search?q=sola...e=lnms&tbm=nws
Some great knowledge being dropped in this thread!
But, knowledge of the Simpsons is sorely lacking. Here is the far better scene to cite at this time:
-Jason "feast on the goo!" Evans
Why are you wasting time here when you could be wasting it by listening to the latest episode of the DBR Podcast?
Asymptomatic transmission of other viruses has been documented. For example with varicella (chickenpox) kids were thought to be contagious about 24 hours before they broke out in a rash.
Transmission of a viral agent depends on a few factors:
1) Shedding of virus by the infected person, including intensity and duration
2) Duration and proximity of exposure
3) Susceptibility of the recipient
With a novel virus, point 3 is especially problematic, because everyone is susceptible. With regard to point 1, sometimes viruses are shed but in amounts that are too small to infect anybody else. Finally, exposure to someone who is shedding enough virus to be infectious doesn't always result in infection, but the longer the duration and the closer the proximity, the more likely the virus is to be transmitted (point 2).
With influenza, the intensity of shedding varies directly with the severity of illness; that is to say, patients are most highly contagious when they are the sickest. Thankfully, that is also when they are more likely to be unable to get out of bed, and therefore they don't come to work. But transmission of flu is probably possible perhaps 12 hours or so before the illness really begins. In other words, traditionally with respiratory viruses, people who are not sick are very unlikely to spread the virus.
I'm not entirely sure how they have reached the conclusion that spread can happen from asymptomatic persons. If it is based on known transmission that would be more worrisome than if it is based strictly on shedding; in other words, if they are saying that they could find the virus in secretions from people who had not yet become sick or who were sick but recovered, that doesn't necessarily prove that the infection could be spread in that way. I would need more information. Specifically, I would need to know how much virus was found in the secretions. We can find even very small numbers (non-transmittable numbers) or even replication-incompetent virus using PCR because it greatly amplifies parts of the virus genome.
Sorry I don't have more information. I'll see if I can ferret it out later today.
"We are not provided with wisdom, we must discover it for ourselves, after a journey through the wilderness which no one else can take for us, an effort which no one can spare us, for our wisdom is the point of view from which we come at last to regard the world." --M. Proust
"We are not provided with wisdom, we must discover it for ourselves, after a journey through the wilderness which no one else can take for us, an effort which no one can spare us, for our wisdom is the point of view from which we come at last to regard the world." --M. Proust
Solano County is the site of Travis Air Force Base, where the Wuhan evacuees were quarantined for 14 days before 180 of them were released: https://abc7news.com/5945344/
That seems too coincidental not to be related.
It's the opening remarks from the WHO's Monday briefing. I'll leave it each of us to try to decide what it means, but I found it somewhat reassuring.
https://www.who.int/dg/speeches/deta...-february-2020
Changes to the preseason baseball schedules in Asia and South Korea:
https://www.mlbtraderumors.com/2020/...ronavirus.html
Per NYT, all coronavirus messaging from federal health officials must now go through VP Pence. So, I guess no more uncleared statements from CDC?
https://www.nytimes.com/2020/02/27/u...rus-pence.html
The vice president’s first move appeared to be aimed at preventing the kind of contradictory statements from White House officials and top government health officials that have plagued the administration’s response. Even during his news conference on Wednesday, Mr. Trump rejected the assessment from a top health official that it was inevitable that the coronavirus would spread more broadly inside the United States.
Dr. Anthony S. Fauci, one of the country’s leading experts on viruses and the director of the National Institute of Allergy and Infections Diseases, told associates that the White House had instructed him not to say anything else without clearance.
The new White House approach came as the Centers for Disease Control and Prevention acknowledged Thursday that a California woman with coronavirus was made to wait days before she was tested for the disease because of the agency’s restrictive criteria about who may get tested.
Putting aside public policy issues which we cannot discuss -- from a public health management perspective this seems wrong. Why would we silence health officials trying to warn folks to prepare?
Last edited by OldPhiKap; 02-27-2020 at 01:33 PM.
rsvman: What are your thoughts on this article?
The new coronavirus has an HIV-like mutation that means its ability to bind with human cells could be up to 1,000 times as strong as the Sars virus, according to new research by scientists in China and Europe.
The discovery could help to explain not only how the infection has spread but also where it came from and how best to fight it.
Scientists showed that Sars (severe acute respiratory syndrome) entered the human body by binding with a receptor protein called ACE2 on a cell membrane. And some early studies suggested that the new coronavirus, which shares about 80 per cent of the genetic structure of Sars, might follow a similar path.
But the ACE2 protein does not exist in large quantities in healthy people, and this partly helped to limit the scale of the Sars outbreak of 2002-03, in which infected about 8,000 people around the world.
Other highly contagious viruses, including HIV and Ebola, target an enzyme called furin, which works as a protein activator in the human body. Many proteins are inactive or dormant when they are produced and have to be “cut” at specific points to activate their various functions.
1) Unlike influenza, coronaviruses are spread in "large droplets," rather than "droplet nuclei." Large droplets are heavy enough that when expelled (for example by coughing or sneezing) they fall within six feet. I think it is unlikely that a virus that spreads in this fashion could ever infect as large a proportion of the U.S. population as influenza does (about 15% each year).
If all coronaviruses are transmitted in a similar way, how this be explained?
COVID.jpg
SARS killed 774 people and infected 8,098 between November 2002 and July 2003. The new coronavirus has killed more than three times that many people in eight weeks.
Everyone that shows up with flu like symptoms can not be tested especially in the early days. So there is good reason for putting restrictions in place. You want your diagnostic tests to go to those most likely to have come into contact with the virus.
That said, I'm a firm believer that the US should have opened up the flood gates some time ago on more relaxed testing. At least testing travelers from countries with active ongoing outbreaks (Italy, Korea, Iran and Japan).
Unlike rsvman, I am not a trained medical professional and have no insider knowledge.
This could help explain why it is so much pathogenic than the regularly circulating coronaviruses. SARS-CoV did not have a furin cleavage site.
Coronaviruses, like all RNA viruses, evolve fairly rapidly under selective pressure, because RNA-dependent RNA polymerases (the enzymes that facilitate replication of the virus genome) lack an editing function. Influenza can evolve almost instantaneously because its genome is segmented, allowing for recombination of different influenza viruses if they simultaneously infect a single cell (this is why they have pandemic potential).
Although coronaviruses do not have a segmented genome, and thus cannot evolve essentially instantaneously, they do have several methods of rapid evolution that are missing in other RNA viruses like RSV. One is deletion mutants. Some strains will pop up that are missing 10-200 amino acids, which can give them very different qualities. Also, they can undergo a process called RNA recombination, caused by discontinous transcription and polymerase jumping.
These could affect tissue tropism and also severity of infection. It seems very likely that this new coronavirus, through some combination of these mechanisms, has evolved to become much more virulent than garden-variety coronaviruses (although less so than SARS-CoV) and apparently to spread more easily (whether this is through improved binding to host cells, increased shedding in patients who aren't sick or are only mildly ill, increased duration or shedding, or a combination of these factors is not yet clear).
Last edited by rsvman; 02-27-2020 at 02:19 PM.
"We are not provided with wisdom, we must discover it for ourselves, after a journey through the wilderness which no one else can take for us, an effort which no one can spare us, for our wisdom is the point of view from which we come at last to regard the world." --M. Proust
That's exactly my concern. China tried to hide the bad news to prevent political fall-out, with disastrous and fatal results. And, no one can trust the data they present because of the same political filter through which real facts are run.
This is health crisis, and we are entitled to the facts without either party or any political group shading them. It's not a political debate, it literally is a matter of life or death as China demonstrated.