• Join our newsletter: 
  • Welcome Guest


    Page 1 of 8 12345 ... LastLast
    Results 1 to 20 of 160
    1. Top | #1
      UpSideDownCarl is online now
      says Krooklyn District Goon Squad
      Commissioner
       
      Equipment Expert
      Super Moderator Country: United States
      UpSideDownCarl's Avatar
      Equipment:
      Blade OSP Virtuoso +
      Forehand Rubber BH:Red Rasanter R48
      Backhand Rubber FH:Black Rasanter R48

      Join Date
      Dec 2010
      Location
      Brooklyn, New York
      Posts
      13,545
      Reviews
      Read 11 Reviews
      Liked 15,015 Times in 7,260 Posts

      SARS-CoVID-2/ CoVID-19/ CoronaVirus: Information Only from Well Informed Members

      So, I just want this to be clear. I closed the last 2 threads on the Novel CoronaVirus Pandemic as it seemed that each, at some point went off into unsubstantiated territory. Nevertheless, with this global crisis, I still feel, having useful information on the subject available to our members will be valuable.

      So, we are going to try something different here.

      The rules of this thread are not the rules of most threads.

      Baal, RainNeverEver, Dr Evil, and Passifid will be the well informed members or "Experts" on the thread since they all have science and medical related backgrounds. They can post as they see fit to provide information and to answer questions.

      Other members can ask questions but cannot simply post thoughts, opinions, answers.

      I will HEAVILY MODERATE the thread so that, if a member, unaware of the rules for this thread, posts content rather than a question, I will delete and inform that member of the special rules for this thread.

      Thank you for you understanding and cooperation in this endeavor. I am looking forward to seeing how this thread turns out.
      Last edited by UpSideDownCarl; 05-09-2020 at 04:39 PM.
      Spin Everything.

    2. The Following 15 Users Like UpSideDownCarl's Post:

      42andbackpains (05-11-2020),deams59 (05-09-2020),FIXPOINT (05-10-2020),goodhand (05-11-2020),Halon X (05-10-2020),Joepole (05-10-2020),mart1nandersson (05-09-2020),Metaxa (05-10-2020),NextLevel (05-09-2020),pingpongpaddy (05-13-2020),shinshiro (07-03-2020),splasher78 (06-11-2020),Suga D (08-25-2020),tropical (05-10-2020),Zaid323918 (05-16-2020)

    3. Top | #2
      Baal is offline
      says Ba'al has spoken
       
      Master TTD Member


      Join Date
      Nov 2010
      Location
      Houston, Texas
      Posts
      3,305
      Reviews
      Read 8 Reviews
      Liked 5,482 Times in 2,271 Posts
      I will start off with some news on the use of common blood pressure medications and susceptibility to infection by SARS-COV-2. Two classes of effective and very widely used blood pressure meds are so-called ACE inhibitors (generic drug names end with -pril, e.g. enalapril) and angiotensin receptor blockers (drug names end with - sartan, e.g. losartan). There was some concern that ACE inhibitors seem to increase the abundance of ACE-2, which the virus uses as a receptor to gain entry into cells. This increase in ACE-2 was seen in some studies in mice given those drugs, but not to my knowledge in humans. Still, people were wondering if their blood pressure meds put them at higher risk. It was a sane question to ask.

      Not to worry it turns out. No fewer than four different peer-reviewed studies have appeared in the last ten days showing no association between use of ACE inhibitors or ARBs and risk of getting Covid-19. Two appeared in the New England Journal of Medicine (a very hard place to get published). In fact, these drugs would be far more likely to protect your lungs and blood vessels since they block a pathway that promotes inflammation and blood vessel constriction.

      This is worth mentioning because there is a VERY high likelihood that some TTD members or their family members are taking these drugs and may have concerns..
      Last edited by Baal; 05-09-2020 at 08:02 PM.

    4. The Following 7 Users Like Baal's Post:

      darucla (05-11-2020),Dr Evil (05-10-2020),Flatstyk (05-09-2020),goodhand (05-11-2020),Suga D (08-25-2020),Tinykin (05-12-2020),UpSideDownCarl (05-09-2020)

    5. Top | #3
      UpSideDownCarl is online now
      says Krooklyn District Goon Squad
      Commissioner
       
      Equipment Expert
      Super Moderator Country: United States
      UpSideDownCarl's Avatar
      Equipment:
      Blade OSP Virtuoso +
      Forehand Rubber BH:Red Rasanter R48
      Backhand Rubber FH:Black Rasanter R48

      Join Date
      Dec 2010
      Location
      Brooklyn, New York
      Posts
      13,545
      Reviews
      Read 11 Reviews
      Liked 15,015 Times in 7,260 Posts
      Quote Originally Posted by Baal View Post
      This is very promising. A human monoclonal antibody that can neutralize SARS-COv-2 and block infection in vitro.

      https://www.nature.com/articles/s41467-020-16256-y
      Can one of you explain what makes this human monoclonal antibody information valuable in a way that some of us lay folk can understand?

    6. The Following User Likes UpSideDownCarl's Post:

      Suga D (08-25-2020)

    7. Top | #4
      Baal is offline
      says Ba'al has spoken
       
      Master TTD Member


      Join Date
      Nov 2010
      Location
      Houston, Texas
      Posts
      3,305
      Reviews
      Read 8 Reviews
      Liked 5,482 Times in 2,271 Posts
      Normally when your body is exposed to a foreign protein (for example a protein that is part of a virus or bacterium) your immune system recognizes it as foreign, and secretes a protein called an antibody that binds to the foreign protein (by recognizing a portion of the protein known as an antigen). That can trigger many different responses. For example, certain kinds of cells with the antibody on the surface can come and engulf or "eat" the invading virus or microbe. Vertebrates can make a vast number of different antibodies that can recognize portions or proteins. When we make vaccines, we are giving the body part of the protein (or DNA or RNA) of the virus in hopes that we make antibodies that will fight it. It turns out that antibodies are incredibly important tools in the research laboratory (we can use them to label or isolate proteins, to see where the proteins they recognize are located, and sometimes even to block their function).

      It turns out that antibodies represent a good starting point for making drugs too. Once a so-called monoclonal antibody is developed, those antibodies can be produced on an industrial scale, and if they are HUMAN monoclonals (as opposed to, say, mouse monoclonals) you can give them to humans and generally they will not themselves be recognized as foreign proteins.

      A lot of drugs in clinical use are derived from human monoclonal antibodies. Here is a link with a partial list. In general, any drug whose generic name ends in --mab is a monoclonal antibody.

      https://www.medicinenet.com/monoclon...es/article.htm

      Basically you are using immunology to discover a perfectly specific drug to target a particular protein.

      In the paper I cited above, the scientists have made a human monoclonal antibody that (a) recognizes the part of the SARS-COV-2 virus that is externally exposed and necessary for it to infect cells and (b) they have shown that this antibody actually blocks the virus from infecting human cells in a dish. The idea is that this antibody ought to be able to do much the same thing that the immune systems do in people who are infected and who don't really get sick. (Recall that recovered Covid-19 patients sometimes donate blood to transfuse into sick people).

      Monoclonal antibodies have to be given by intravenous infusions (they are proteins and would be destroyed in the stomach). They tend to be REALLY expensive. For example, adalimumab (Humira) which inactivates tumor necrosis factor (TNF which is something I have worked on), costs about $6,000 per month without insurance in the US!!! An advantage of monoclonal antibodies is that they tend to not have "off-target" effects (they are screened for this extensively during development). That means they are usually pretty well tolerated, the side effects are due to their action if the protein they are targeting plays some role in normal physiology. For example, Humira can make rheumatoid arthritis and Chron's disease patients more prone to infections because TNF is part of the normal response to infections. But the proteins of SARS-COV-2 are foreign and so clearly play NO role in normal physiology. So one would not anticipate in advance much in the way of an adverse side effect.

      Therefore it seems to be me that this discovery is a crucial proof-of-concept and perhaps could lead in the fullness of time to a therapeutic agent.

      I say fullness of time because it takes a lot longer to approve an entirely NEW drug that it does to repurpose and existing drug that has already gone through all the safety testing, manufacturing infrastructure, etc.

    8. The Following 2 Users Like Baal's Post:

      Suga D (08-25-2020),UpSideDownCarl (05-10-2020)

    9. Top | #5
      Baal is offline
      says Ba'al has spoken
       
      Master TTD Member


      Join Date
      Nov 2010
      Location
      Houston, Texas
      Posts
      3,305
      Reviews
      Read 8 Reviews
      Liked 5,482 Times in 2,271 Posts
      In light of my last post, though, I am even more excited by this article (peer reviewed and in press):

      https://www.cell.com/pb-assets/produ...D-20-00739.pdf

      The idea here is that ACE-2 is the protein on human cells that SARS-COV-2 binds to in order to infect the cells. ACE-2 is mostly on the surface of cells, but it can be shed from the cell and in that case is a so-called soluble form of the protein. The soluble ACE-2 can still bind to SARS-COV-2, but it won't help the virus enter the cell. In fact, the soluble ACE-2 can actually COMPETE with the cell surface ACE-2 for the virus and thereby prevent infections. In pharmacology we call things like that "decoy receptors". This paper shows, again in a dish, but using highly organized human systems called organoids, that soluble ACE-2 prevents infection. In a way it is working somewhat like the monoclonal antobody (although soluble ACE-2 has other potentially beneficial tricks up its sleeve).

      What is really cool about that is that one company has ALREADY turned soluble ACE-2 into a drug!! On April 2, a company called Apeiron got approval from regulators in Austria, Germany and Denmark to launch a Phase II trial of a drug they call APNO1 for Covid-19. APNO1 is in fact a soluble form of ACE-2. And it has been proposed as a therapy for a wide range of things. It has been around since before 2010.

      https://clinicaltrials.gov/ct2/show/NCT00886353

      Actually acting as a decoy receptor is not the only reason why APNO1 might be helpful in Covid-19, but for now I will leave it here. Hopefully we will hear something positive if they can get enough patients to do a good trial. My thinking is that it would be something you would want to use fairly early on.

      The possible downside though is something Rain mentioned earlier, which is that ACE-2 may not be the only way that SARS-COV-2 has to enter cells.
      Last edited by Baal; 05-10-2020 at 11:10 PM.

    10. The Following 2 Users Like Baal's Post:

      Suga D (08-25-2020),UpSideDownCarl (05-10-2020)

    11. Top | #6
      Dr Evil is offline
      This user has no status.
       
      Established TTD Member Country: United States


      Join Date
      Dec 2018
      Posts
      168
      Reviews
      Read 0 Reviews
      Liked 180 Times in 95 Posts
      Quote Originally Posted by Baal View Post
      I will start off with some news on the use of common blood pressure medications and susceptibility to infection by SARS-COV-2. Two classes of effective and very widely used blood pressure meds are so-called ACE inhibitors (generic drug names end with -pril, e.g. enalapril) and angiotensin receptor blockers (drug names end with - sartan, e.g. losartan). There was some concern that ACE inhibitors seem to increase the abundance of ACE-2, which the virus uses as a receptor to gain entry into cells. This increase in ACE-2 was seen in some studies in mice given those drugs, but not to my knowledge in humans. Still, people were wondering if their blood pressure meds put them at higher risk. It was a sane question to ask.

      Not to worry it turns out. No fewer than four different peer-reviewed studies have appeared in the last ten days showing no association between use of ACE inhibitors or ARBs and risk of getting Covid-19. Two appeared in the New England Journal of Medicine (a very hard place to get published). In fact, these drugs would be far more likely to protect your lungs and blood vessels since they block a pathway that promotes inflammation and blood vessel constriction.

      This is worth mentioning because there is a VERY high likelihood that some TTD members or their family members are taking these drugs and may have concerns..
      Definitely worth mentioning. Nobody should stop or change medications because of something they read online about this virus. When in doubt check with your doctor. And please don't avoid going to the hospital if necessary. There have been some deaths in NYC because heart attack and stroke victims were too afraid of catching the virus and put off calling an ambulance until too late.

    12. The Following 6 Users Like Dr Evil's Post:

      Baal (05-10-2020),NextLevel (05-10-2020),Suga D (08-25-2020),Tinykin (05-12-2020),UpSideDownCarl (05-10-2020),Vlad Celler (05-10-2020)

    13. Top | #7
      rainneverever is offline
      This user has no status.
       
      Elite TTD Member Country: China


      Join Date
      Sep 2016
      Posts
      1,022
      Reviews
      Read 0 Reviews
      Liked 1,960 Times in 651 Posts
      Baal has explained a lot about antibodies, I want to add some points.


      1. Can a blood test tell people if they have protective antibodies (Abs) against COVID-19?
      When people are infected by SARS-CoV-2, many types and kinds of Abs will be produced. Most (all?) of them are binding Abs, which bind to certain regions of SARS-CoV-2 (i.e., S protein on the outer part of the virus, N protein on the inner part of the virus, etc). However, not all of them are neutralizing Abs (protective), which have the ability to inhibit viral infection; Abs against N protein probably cannot inhibit infection because N protein on a "live" virus was not exposed and accessible. The commercial IgM/IgG Ab blood tests (ELISA run in a lab or test paper run on site/at home) can only tell whether there are binding Abs in one's blood - a positive result suggesting a current/past infection. The only way to tell whether there are neutralizing Abs in one's blood is run a several-day long experiment, to grow permissive model cells, challenge the cells with real virus (high level of safety regulations) or with pseudo virus (very low safety regulations), -/+ the plasma/serum sample to be tested, then after 1-2 days of infection, collect the culture medium and compare how much virus is released from the cells. Neutralizing Abs can inhibit viral infections and result in a reduction of viral release. When officials and "experts" say the commercial IgM/IgG Ab tests can tell who has protective Abs and are ready to go back to work, I would say that's a white lie. The nucleic acid test is required to see if people with Abs still shed virus or not.


      2. Can anyone infected with COVID-19 or receive vaccine develop neutralizing Abs?
      We don't know yet and researchers are testing. I believe most people do but there are always outliers. We should keep in mind that there are individual variations among us.
      https://www.medrxiv.org/content/10.1....30.20047365v2 This preprint found that neutralizing Abs were not detected in a few mild symptom COVID patients. One can argue that this was due to the detection sensitivity of the experiment. We have to wait for more reports, especially from vaccine trials.Some people may get infected more than once if they indeed cannot develop neutralizing Abs after infection or vaccination. But that won't affect the population much as we only need ~70% (1-1/R0) not 100% of population immuned to achieve herd immunity (by infection or vaccination).


      3. Monoclonal Ab (mAb) drugs vs convalescent plasma
      Both mAb and convalescent plasma have to be neutralizing Abs in order to work. Many mAbs have been identified by research institutes and pharmaceutical companies. However, I don't think any one is on clinical trial yet. There are studies and news reports that convalescent plasma therapy worked for severe COVID patients and some randomized trials are in progress.
      https://jamanetwork.com/journals/jam...rticle/2763983
      https://www.pnas.org/content/117/17/9490
      Is it necessary to develop mAb drugs if convalescent plasma can be collected from millions of the recovered? The effectiveness of neutralizing Abs from different donors of convalescent plasma may vary a lot (see the preprint in 2); the blood also contained non-neutralizing Abs. In contrast, mAbs are easier to do quality control and standardized during manufacture. Maybe not a good metaphor: You want to obtain Vitamin C from fruits and you can access a few kiwi and many apples, and you worry about too much sugar by eating fruits to get enough Vitamin C; then some companies come in saying, "Don't worry, we are making Vitamin C tablets".
      Many US companies launched COVID-19 mAbs projects early on: on 2.12 Vir announced hits from SARS survivors; on 3.12, Eli Lilly announced hits from COVID survivors; on 3.17, Regeneron announced hits from humanized mice. There are discussions that multiple mAbs should be considered to use as a cocktail; that will lead to more complicated and expensive clinical trials. Manufacture cost of mAb is high, ~$260 per gram, but retail price can be much higher, for example an mAb anticancer drug costs $9500 per gram. It is relatively easy and cheap to identify COVID mAbs hits (unlike anticancer drugs, time and money were spent to search for novel targets), I don't see why companies won't pursue the profit.


      4. Why antibodies from SARS survivors worked for COVID?
      It has been reported by different research groups since Feb that antibodies against SARS (either mAbs from SARS survivors, or polyclonal horse serum which were used to treat SARS patients) had neutralization effect on SARS-CoV-2. Although SARS and SARS-CoV-2 have many sequence differences, they share 3D structural similarities. Our Abs are not that "sensitive" to identify such differences, which may be good news as the differences among SARS-CoV-2 strains must be smaller than SARS vs SARS-CoV-2. It is less concerning that the vaccine will fail soon as flu shot.
      I heard that antibodies against alpha coronavirus (common cold) may also cross-react with SARS-CoV-2 (no published data though). This may explain why some people were less susceptible when they contacted the infected. But it may also cause false positive issue for Abs blood test. There are recent news reports that people tested positive for COVID Abs and thought they caught the virus as early as Sep 2019. It is hard to interpret the Ab test results without having swab nucleic acid tests, X-ray/CT scans, and other clinical investigations.
      Last edited by rainneverever; 05-10-2020 at 07:30 PM.

    14. The Following 6 Users Like rainneverever's Post:

      Baal (05-10-2020),Dr Evil (05-12-2020),goodhand (05-11-2020),Joepole (05-11-2020),Suga D (08-25-2020),UpSideDownCarl (05-10-2020)

    15. Top | #8
      Baal is offline
      says Ba'al has spoken
       
      Master TTD Member


      Join Date
      Nov 2010
      Location
      Houston, Texas
      Posts
      3,305
      Reviews
      Read 8 Reviews
      Liked 5,482 Times in 2,271 Posts
      That was interesting Rain. Definitely stuff there I didnt know or hadn't thought about. What I find particularly interesting about the JAMA and PNAS papers you mention above is that recovered patients' plasma were effective in seriously ill patients at a quite advanced stage. That suggests that therapies based on neutralizing the virus (like a monoclonal antibody or a decoy receptor) might be useful throughout the disease process, not just early on.

      In terms of point 4 in Rain's post, she is noting that at least some antisera against OTHER coronaviruses have been reported to be at least partially protective against this one. I am not entirely surprised by that, but still it is important to know that. From my non-immunologist perspective, this augurs well that we will at some point have effective vaccines. They may even provide at least some protection against the NEXT coronavirus that jumps into humans and kills thousands of people. (Don't think thus will be the last one, it is the third one in around two decades).
      Last edited by Baal; 05-10-2020 at 11:23 PM.

    16. The Following 3 Users Like Baal's Post:

      pingpongpaddy (05-13-2020),Suga D (08-25-2020),UpSideDownCarl (05-12-2020)

    17. Top | #9
      darucla is offline
      says I actually do drink...wine.
       
      Advanced TTD Member Country: Europe
      darucla's Avatar
      Equipment:
      Blade In flux
      Forehand Rubber In flux
      Backhand Rubber Hurricane 3 Neo Black

      Join Date
      Dec 2016
      Location
      Norfolk
      Posts
      253
      Reviews
      Read 0 Reviews
      Liked 193 Times in 96 Posts
      Quote Originally Posted by Baal View Post
      ...No fewer than four different peer-reviewed studies have appeared in the last ten days showing no association between use of ACE inhibitors or ARBs and risk of getting Covid-19. Two appeared in the New England Journal of Medicine (a very hard place to get published). In fact, these drugs would be far more likely to protect your lungs and blood vessels since they block a pathway that promotes inflammation and blood vessel constriction.

      This is worth mentioning because there is a VERY high likelihood that some TTD members or their family members are taking these drugs and may have concerns..
      As one of the members who takes a sartan every day, I am very encouraged to hear this. Thank you.

    18. The Following 3 Users Like darucla's Post:

      goodhand (05-11-2020),pingpongpaddy (05-13-2020),UpSideDownCarl (05-11-2020)

    19. Top | #10
      Baal is offline
      says Ba'al has spoken
       
      Master TTD Member


      Join Date
      Nov 2010
      Location
      Houston, Texas
      Posts
      3,305
      Reviews
      Read 8 Reviews
      Liked 5,482 Times in 2,271 Posts
      Darucla, then you may find a bit of extra information even more reassuring. The likelihood is that sartans, if they have any effect at all in a Covid-19 infection, would be protective. There are many reasons to think this. It all pertains to the dynamics of the so-called renin-angiotensin system and it is pretty complicated to go into here. But the short story is that angiotensin II (Ang II) tends to be pro-inflammatory and too much of it produces bad effects in lungs, heart, kidney, blood vessels, etc. and increases blood pressure and blood volume. It acts on the angiotensin type 1 receptor, and sartans inhibit that receptor. That is why sartans lower your blood pressure.

      The enzyme ACE-2 chops off one amino acid and thereby converts Ang II to angiotensin 1-7 (Ang 1-7). Ang 1-7 acts mostly in opposition to Ang II (and it acts on a completely different type of receptor called the Mas receptor). The virus causes internalization of ACE-2 so (in addition to causing infection of cells) it also makes it so there is less conversion of Ang II to Ang 1-7. It changes the balance in a way that would tend to promote inflammation, heart, kidney, and lung disease, etc). Sartans should therefore lower the effects of Ang II relative to Ang 1-7 and so might be protective.

      I mentioned in a long post above that the recombinant soluble form of ACE-2 had more than one trick up its sleeve. It could act as a decoy receptor to prevent infection as I mentioned. However it also should increase conversion of circulating Ang II to Ang 1-7, which should be protective.

      Some pharmacologists also think that infusions of Ang 1-7 by itself might be protective (I certainly think there are a ton of reasons to think this would be the case) and there is a clinical trial ongoing to test this idea in Covid-19. https://clinicaltrials.gov/ct2/show/NCT04332666
      Last edited by Baal; 05-11-2020 at 02:29 PM.

    20. The Following 4 Users Like Baal's Post:

      darucla (05-12-2020),goodhand (05-11-2020),pingpongpaddy (05-13-2020),UpSideDownCarl (05-11-2020)

    21. Top | #11
      Baal is offline
      says Ba'al has spoken
       
      Master TTD Member


      Join Date
      Nov 2010
      Location
      Houston, Texas
      Posts
      3,305
      Reviews
      Read 8 Reviews
      Liked 5,482 Times in 2,271 Posts
      I have given some thought about things people should consider if they are deciding whether to play if their clubs open up (as some in the US are doing).

      So here is a checklist for assessing your risk tolerance. The factors will not be the same for everyone everywhere, and some of these things are frankly very difficult to know in the US, such as percentage of people walking around who might be infected:



      1. What are the odds my playing partner is infected (this depends on where you live and is something that is changing a bit over time, but be aware that infected people can be asymptomatic and contagious, and infection rates are actually anybody's guess in a lot of places).



      2. How big is the playing room and how many people are in it, what is the table spacing, how good is the room ventilation, and what kinds of sanitizing protocols if any are in place at the club?


      3. What are my own personal risk factors (age, do I have other conditions that might predict a bad outcome such as overweight, high blood pressure, prior heart attacks, diabetes, autoimmune disease, history of cancer, COPD, vitamin D deficiency, general fitness level, etc.). This may be the single most important consideration.


      4. What other risk factors would come into play if I were to get infected (do I have good heath insurance, do I live alone, do I have contact with vulnerable people such as older relatives, how would it affect my job if I were to test positive, etc. etc.).


      5. What kind of masks are available to me and can I wear one while playing in some degree of comfort without it chafing my nose, ears etc. and without it flopping around so much it is a distraction. Is the type mask I can source likely to protect me at all (a bandana probably won't be much good).

      5b. (Added thanks to Dr. Evil). Is my playing partner willing to wear a mask too so as to protect me?

      6. Does the club have a good system for allocating tables and dealing with people who are waiting, and are people screaming or cho-ing like banshees?

      7. Under the conditions that I have to endure to play TT, is it still enough fun to bother or are there other activities I can do for awhile until things get more normal? How much do I need TT to stay sane?

      8. Local laws and decrees affecting sports.
      Last edited by Baal; 05-13-2020 at 03:42 AM.

    22. The Following 3 Users Like Baal's Post:

      Dr Evil (05-12-2020),goodhand (05-13-2020),UpSideDownCarl (05-12-2020)

    23. Top | #12
      Takkyu_ga_suki is offline
      This user has no status.
       
      TTD Member Country: United States


      Join Date
      Nov 2019
      Posts
      27
      Reviews
      Read 0 Reviews
      Liked 7 Times in 4 Posts
      Let's say I am the first customer of the day and have a coaching lesson for one hour with nobody else in the room. Ventilation is not great.... one open door. Maybe a floor fan blowing towards the door.

      If I'm wearing a level 1 ASTM mask, don't touch my face, wash hands, use alcohol and such afterwards, am I significantly reducing my risk of infection (with the mask)? Very crude ballpark percentage? What if my coach wears a mask as well?

      [I don't plan to play again, until the number of cases in my area drops drastically, but my club is re-opening. Have heard different opinions from docs/medical folks concerning masks. Always looking for another data point.]

      Edited to add: For this example, let's say the coach does have the virus, is asymptomatic, and is at a peak contagion level.
      Last edited by Takkyu_ga_suki; 05-12-2020 at 09:52 PM.

    24. Top | #13
      Baal is offline
      says Ba'al has spoken
       
      Master TTD Member


      Join Date
      Nov 2010
      Location
      Houston, Texas
      Posts
      3,305
      Reviews
      Read 8 Reviews
      Liked 5,482 Times in 2,271 Posts
      Quote Originally Posted by Takkyu_ga_suki View Post
      Let's say I am the first customer of the day and have a coaching lesson for one hour with nobody else in the room. Ventilation is not great.... one open door. Maybe a floor fan blowing towards the door.

      If I'm wearing a level 1 ASTM mask, don't touch my face, wash hands, use alcohol and such afterwards, am I significantly reducing my risk of infection (with the mask)? Very crude ballpark percentage? What if my coach wears a mask as well?

      [I don't plan to play again, until the number of cases in my area drops drastically, but my club is re-opening. Have heard different opinions from docs/medical folks concerning masks. Always looking for another data point.]

      Edited to add: For this example, let's say the coach does have the virus, is asymptomatic, and is at a peak contagion level.
      Takyu, I thought about your question fir awhile and concluded I just can't put a number on the % reduction in risk. Maybe Dr. Evil or Pasifid can give their inputs. Without trying to give a number, I would not personally feel real comfortable in a Level 1 ASTM, especially if it turns out the coach is contagious. But some health care providers have to see Covid-19 patients and that's about what they have (and too many are getting sick). Then again a TT club is not a hospital.

      The thing about a level 1 mask is lots of air can get in around the sides. Personally I have other things I can do to stay fit for awhile besides TT. Others may feel a stronger compulsion to play.

      I think people are going to have to make their own guesses on risk.
      Last edited by Baal; 05-12-2020 at 11:02 PM.

    25. The Following 2 Users Like Baal's Post:

      Takkyu_ga_suki (05-12-2020),UpSideDownCarl (05-13-2020)

    26. Top | #14
      Takkyu_ga_suki is offline
      This user has no status.
       
      TTD Member Country: United States


      Join Date
      Nov 2019
      Posts
      27
      Reviews
      Read 0 Reviews
      Liked 7 Times in 4 Posts
      Thanks Baal. I feel the risk is not worth it either for the same reasons. Confirmation bias. ;-)

      Edited to add:

      I'm real confused by this whole situation. On the one hand I know of crowded retail stores, where all the workers wear masks, and to-date no worker has come down with an infection. It could be the masks, or that nobody who is infected has frequented the store.

      On the other hand one person in a nightclub in South Korea infected 86 people. Was that due to poor ventilation, no social distancing, how long was the carrier and the participants in the same room?

      It's frustrating because most of the news reports just focus on raw stats, but seldom the circumstances that gave rise to specific clusters, making it virtually impossible to estimate what the real risks are. I know the R0 is at least 2.5 times higher than regular flu, but it would be nice to know better how this thing spreads.

      I have also heard how some docs observe other medical workers touching their faces etc., and not really observing best practices. Very frustrating situation, of course.
      Last edited by Takkyu_ga_suki; 05-12-2020 at 11:27 PM.

    27. Top | #15
      Dr Evil is offline
      This user has no status.
       
      Established TTD Member Country: United States


      Join Date
      Dec 2018
      Posts
      168
      Reviews
      Read 0 Reviews
      Liked 180 Times in 95 Posts
      Quote Originally Posted by Takkyu_ga_suki View Post
      Let's say I am the first customer of the day and have a coaching lesson for one hour with nobody else in the room. Ventilation is not great.... one open door. Maybe a floor fan blowing towards the door.

      If I'm wearing a level 1 ASTM mask, don't touch my face, wash hands, use alcohol and such afterwards, am I significantly reducing my risk of infection (with the mask)? Very crude ballpark percentage? What if my coach wears a mask as well?

      [I don't plan to play again, until the number of cases in my area drops drastically, but my club is re-opening. Have heard different opinions from docs/medical folks concerning masks. Always looking for another data point.]

      Edited to add: For this example, let's say the coach does have the virus, is asymptomatic, and is at a peak contagion level.
      I can't even give you a ballpark percentage. A few observations, though:

      The mask that protects you will be the one your coach is wearing, not the one you're wearing.


      Masks that protect you from getting the virus -- like N95s -- make an airtight seal around your mouth and nose. They have to be properly fitted, they're held tight to your face usually by two elastic bands, and they're uncomfortable. Not something you'd want to use to play tt, although they do have the advantage of not fogging up your glasses because of the airtight seal.


      Most masks, including surgical masks, protect you from transmitting the virus to other people. They catch droplets, and can even cut down somewhat on aerosols (i.e., smaller droplets that float in the air longer), that are projected with every exhalation. Ideally they're made of tightly woven material (so they could block most light from a flashlight), possibly with more than one layer. The trade off is that the better they block droplets/aerosols, the stiffer and more uncomfortable they're likely to be.


      The other factors that will offer most protection are whatever minimizes the concentration of virus in the air. So maximum air (big space, high ceiling, good ventilation), and minimum people.

    28. The Following 4 Users Like Dr Evil's Post:

      Baal (05-13-2020),goodhand (05-13-2020),Takkyu_ga_suki (05-12-2020),UpSideDownCarl (05-14-2020)

    29. Top | #16
      Takkyu_ga_suki is offline
      This user has no status.
       
      TTD Member Country: United States


      Join Date
      Nov 2019
      Posts
      27
      Reviews
      Read 0 Reviews
      Liked 7 Times in 4 Posts
      Ah, Dr. Evil, you bring up another good point, inadvertently. I don't wear glasses, but of course particles do penetrate that way. Hmmm... seems like the only way to safely play is with a full face guard! I do know of somebody in Taiwan who played with one. I should have stayed there instead of returning to the US. I could be playing now... *sigh*

      Guess I won't be playing for a while.... very depressing. But thanks for the feedback, guys.

    30. Top | #17
      Baal is offline
      says Ba'al has spoken
       
      Master TTD Member


      Join Date
      Nov 2010
      Location
      Houston, Texas
      Posts
      3,305
      Reviews
      Read 8 Reviews
      Liked 5,482 Times in 2,271 Posts
      Yep. I've worn N95 masks doing surgery on animals (we had some in the lab and I had gotten pretty allergic to rats and mice at a certain point). Dr. Evil is right, they are pretty uncomfortable because they do fit pretty tight. That's the whole point. They can pull pretty hard on your ears too. I would never be able to play TT in one.

      And Dr. Evil raises the crucial point that surgical masks are more to keep the stuff coming out of YOUR nose and mouth from infecting other people (like someone you are operating on).

      The other thing in response to Takyu's question about people who get sick or don't, is that there is a random or "stochastic" element to all of this. Sometimes it's just bad luck that you encounter some super-spreader. Of course bars are not always known for their proper ventilation.

    31. The Following User Likes Baal's Post:

      UpSideDownCarl (05-14-2020)

    32. Top | #18
      rainneverever is offline
      This user has no status.
       
      Elite TTD Member Country: China


      Join Date
      Sep 2016
      Posts
      1,022
      Reviews
      Read 0 Reviews
      Liked 1,960 Times in 651 Posts
      Development and Validation of a Clinical Risk Score to Predict the Occurrence of Critical Illness in Hospitalized Patients With COVID-19
      https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/2766086

      an online risk score calculator developed by Guangzhou from chest radiography abnormality, age, hemoptysis, dyspnea, unconsciousness, number of comorbidities, cancer history, neutrophil-to-lymphocyte ratio, lactate dehydrogenase, and direct bilirubin.
      http://118.126.104.170/

    33. The Following 2 Users Like rainneverever's Post:

      Dr Evil (05-14-2020),UpSideDownCarl (05-14-2020)

    34. Top | #19
      Baal is offline
      says Ba'al has spoken
       
      Master TTD Member


      Join Date
      Nov 2010
      Location
      Houston, Texas
      Posts
      3,305
      Reviews
      Read 8 Reviews
      Liked 5,482 Times in 2,271 Posts
      There is reasonably good evidence that Vitamin D supplementation reduces duration and severity of a range of respiratory infections.

      https://www.bmj.com/content/356/bmj.i6583

      Practical aspects are that it has a stronger effect in people who are deficient, and regular (daily) doses work and single large monthly doses don't.

      There is a preprint making the rounds from some biomedical engineers at Northwestern suggesting people who are deficient get more severe Covid-19. I doubt it will get through peer review because the authors didn't have data on serum Vit D in actual Covid-19 patients, rather they were using national means and other surrogate measures that generally correlate with patient Vit D levels. (Countries with low average blood Vit D levels have higher Covud-19`mortality rates).. It is actually not a particularly well executed study and also I'm too lazy link to it. You can find it easily. Also correlation is not causation, etc. etc. (Edit added and there is a second very similar one from Cambridge in UK).

      With that said there are a LOT of reasons why this may very well be true. Vit D can modulate innate immune responses in complex ways and can reduce cytokine storm, inhibits bad guys like IL-6 and TNF. Vit D can stimulate immune cells to secrete peptides that bind pathogens including enveloped viruses like SARS-COV-2, and causing them to aggregate (these are not antibodies, they are other proteins, for example the cathelicidin LL-37 and defensins). And of course, there are the data in the metaanalysis I linked above.

      So why not take a Vit D supplement? If you haven't actually ever had it measured you might be surprised to learn there is a pretty good chance you ARE deficient if you dont get outside very much, especially if you have darker skin. Our species didn't evolve to spend most of our lives indoors, but that's what most people do. And there is a lot of info indicating safety. How much to take? Say 2,000 or even 5,000 IU per day.

      Edit added: There are also some very small observational studies on patient outcomes vs serum Vit D from patients in south Asia. All the data point in the same direction. It is not a good time to be Vit D deficient.
      Last edited by Baal; 05-14-2020 at 01:42 AM.

    35. The Following 2 Users Like Baal's Post:

      Dr Evil (05-14-2020),UpSideDownCarl (05-14-2020)

    36. Top | #20
      Baal is offline
      says Ba'al has spoken
       
      Master TTD Member


      Join Date
      Nov 2010
      Location
      Houston, Texas
      Posts
      3,305
      Reviews
      Read 8 Reviews
      Liked 5,482 Times in 2,271 Posts
      Here is an interesting discussion for non specialists on how the virus gets into droplets, and implications for use of masks. For us there are a few things we could take away. One is that choing should not be allowed once clubs reopen! The louder you speak the more droplets are emitted.

      http://blog.pnas.org/2020/04/fluid-d...read-covid-19/

      And here is an analysis of how long the largest droplets emitted by speech stay in the air.

      https://www.pnas.org/content/early/2.../12/2006874117
      Last edited by Baal; 05-14-2020 at 03:45 PM.

    37. The Following 3 Users Like Baal's Post:

      Dr Evil (05-14-2020),Joepole (05-14-2020),UpSideDownCarl (05-14-2020)

    Page 1 of 8 12345 ... LastLast

    Tags for this Thread

    Posting Permissions

    • You may not post new threads
    • You may not post replies
    • You may not post attachments
    • You may not edit your posts
    •  
    Log in or Register
    BACK TO TOP