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February 13
editWhat does "Transferred to Expedition 14" mean in List of International Space Station expeditions?
editI didn't understand "Transferred to Expedition 14". Please explain
And also tell me why "Transferred to Expedition 13" not occurred? Rizosome (talk) 00:23, 13 February 2021 (UTC)
- WAG: for the same reason that there's no 13th floor in most (US) high-rise buildings? 2603:6081:1C00:1187:BCB8:5C65:41CB:FA6C (talk) 03:08, 13 February 2021 (UTC)
- See: Triskaidekaphobia#Effect on US Shuttle program mission naming (although ISS is not mentioned) --2603:6081:1C00:1187:BCB8:5C65:41CB:FA6C (talk) 03:13, 13 February 2021 (UTC)
- No, it has nothing whatsoever to do with that.
- Expedition 13, April 2006 to September 2006, was marked by Soyuz TMA-8's time docked to the Station, with its crew Pavel Vinogradov & Jeffrey Williams . Expedition 14, September 2006 to April 2007, was marked by Soyuz TMA-9's time docked to the Station, with its crew Michael López-Alegría & Mikhail Tyurin. Thomas Reiter arrived in July 2006 onboard the Space Shuttle Discovery flying mission STS-121, at which point he joined Expedition 13, which was already in progress. He remained on board the ISS when the expedition number incremented from 13 to 14 in September 2006, and thus it is said he "Transferred to Expedition 14" instead of launching to join that expedition.
- No one "Transferred to Expedition 13" because both members of Expedition 12 returned to Earth at the end of that expedition. -- ToE 03:26, 13 February 2021 (UTC)
- My apologies; I was just loitering on the ref desks awaiting a response to an unrelated query. 2603:6081:1C00:1187:BCB8:5C65:41CB:FA6C (talk) 03:38, 13 February 2021 (UTC)
- Note that expeditions 13 & 14 overlapped by 10 days -- the time during which both TMA-8 and TMA-9 were docked to the ISS. I wondered if Thomas Reiter was considered a member of both expeditions at that time, but suspected that he officially transferred from 13 to 14 at the same time command of the ISS was transferred from Pavel Vinogradov to Michael López-Alegría on 27 September, the day before TMA-8 departed. But this European Space Agency release noting the command transfer says that Reiter "became a member of the Expedition 14 crew shortly after the arrival of the Soyuz TMA-9 spacecraft last week". That was probably when he transferred his custom-molded seat liner from TMA-8 to TMA-9. -- ToE 04:05, 13 February 2021 (UTC)
@ToE: Now I understood very well Thomas Reiter stayed in ISS until Sunita Williams space shuttle docked to ISS. Rizosome (talk) 19:53, 13 February 2021 (UTC)
- Precisely. Williams then joined Expedition 14 in progress, taking Reiter's place, and when the expedition number incremented she was transferred to Expedition 15, as noted in our table. -- ToE 22:50, 13 February 2021 (UTC)
COVID origin; extra Q
edit(I didn't know whether to ask a new Q or post this with the Feb10 Q);
Are humans good enough (now) that they can catalogue every bat [and rat...] virus and create vaccines … so that there's no more species jumping?
MBG02 (talk) 15:26, 13 February 2021 (UTC)
- The current issue of National Geographic's cover story is about viruses. There are a LOT of viruses out there. I recommend that you read it, if you can find it. ←Baseball Bugs What's up, Doc? carrots→ 15:38, 13 February 2021 (UTC)
- You can't make a vaccine for use in humans to a virus that cannot infect humans in the first place. --Khajidha (talk) 16:28, 13 February 2021 (UTC)
- Making and distributing a vaccine for every virus that could possibly jump to humans? No, can't be done. For one of the most deadly zoonotic viruses of recent decades, HIV, we don't even have a vaccine, despite trying really hard. And even if we could, it's mostly the shareholders of the pharmaceutical companies who would be happy, as it will cost trillions of euros each year. There are far more cost-effective ways of saving life-years. New zoonotic diseases don't take that many life-years anyway. PiusImpavidus (talk) 17:45, 14 February 2021 (UTC)
- We don't even know every species of bat on the planet. We have no way of knowing every type of virus that can infect them. The most recently discovered species of bat was announced a month ago. The diversity of life on earth is pretty amazing; it is estimated that 86% of plant and animal species have yet to be discovered; and that doesn't even include things like viruses. --Jayron32 13:53, 15 February 2021 (UTC)
Can a human body cope with a thousand (or a million) vaccines? MBG02 (talk) 17:14, 13 February 2021 (UTC)
- It seems unlikely to me that our immune system can keep up with being primed to react to a million antigens. Being able to react promptly against pathogens comes with a cost; as it evolved, natural selection developed a balance between the costs of being underprepared and being overprepared. --Lambiam 21:06, 13 February 2021 (UTC)
- The immune system is exposed to an enormous number of antigens over a lifetime, and has a concomitantly enormous capacity to respond to them. Here's one analysis of this. Now, sometimes vaccines can have issues stimulating enough of an immune response to generate immunological memory; that might be what you're referring to. Many vaccines require adjuvants to provoke a stronger immune response. --47.152.93.24 (talk) 16:39, 14 February 2021 (UTC)
- The estimate given in that analysis (targeting infants) is that they "would have the theoretical capacity to respond to about 10 000 vaccines at any one time", which is far less than a million. --Lambiam 09:50, 16 February 2021 (UTC)
- The immune system is exposed to an enormous number of antigens over a lifetime, and has a concomitantly enormous capacity to respond to them. Here's one analysis of this. Now, sometimes vaccines can have issues stimulating enough of an immune response to generate immunological memory; that might be what you're referring to. Many vaccines require adjuvants to provoke a stronger immune response. --47.152.93.24 (talk) 16:39, 14 February 2021 (UTC)
COVID-19 vaccines safety
editI've looked in the archives before posting this.
For a vaccine that causes body cells to reproduce spike proteins (I know mRNA vaccines do that), what keeps the immune system mistaking other, normal proteins on "infected" cells and turn against the body by mistake. Is that how some autoimmune diseases originate, after a viral infection? Would a vaccine that doesn't cause the body to replicate spike proteins, though less effective, be safer as a result, because they don't ask the body to produce viral proteins? Novavax, which injects the spike proteins, and the Chinese' inactivated virus program, are the only such candidates I know of.
Secondly, everyone says that a fever after the second dose (of an mRNA vaccine, though all vaccines may cause it even if only in a minority of cases) is a sign that the immune system is working, but let's face it, the vaccine is treated as an infection more severely than many people experience more than once several years. It's an inflammatory reaction, and we've only recently begun finding out how many diseases are caused by inflammations, including cancer and heart disease. What people describe as the side effects are what I used to experience from flu, so what I'm being asked to do, as someone who gets a flu shot every year to avoid fevers, is to get a flu--I mean vaccination--once every year or more, depending on how fast the virus mutates. Short of the more severe consequences of a flu, it's like asking my body to withstand a flu infection every year.
The vaccine may be necessary for people who have to work outside the home, but I don't have to do that right now, and I've a supply of respirators.
Thank you. Imagine Reason (talk) 17:26, 13 February 2021 (UTC)
- When a virus infects a cell, it "hijacks" it and makes the cell churn out copies of itself. The neat thing about these RNA vaccines is they're like "fake" viruses that can't reproduce (because they're not actually complete viruses) but still generate immunity to the packaged antigen. The immune system machinery works the same regardless of whether antigens get produced by the body's infected cells, or are introduced in an inactivated vaccine, subunit vaccine, etc.; antigens get detected as "non-self", taken up by lymphocytes, and hauled off to the lymph nodes. The immune system has extensive and fascinating mechanisms to prevent autoimmunity, including presenting developing lymphocytes with "self" proteins and signalling those that respond to die from apoptosis.
- Inflammation is maladaptive when it's chronic, meaning persistent. This is what promotes the development of bad stuff. Acute inflammation isn't really anything to worry about, apart from the unpleasant symptoms while it lasts. --47.152.93.24 (talk) 17:05, 14 February 2021 (UTC)
- To answer your first part, have a look at the article on Clonal selection. The idea is that early in our development in our immune cells the DNA coding for the antigen binding site mutates a lot randomly, so that different immune cells will each bind to different antigens. Those that bind to our own tissues at that stage in development are destroyed. Thus the only immune cells left are ones that do not bind to self: if they bind to something, it must be foreign. If these survivors ever encounter their antigen, they activate and trigger an immune reaction; that includes reproducing themselves so that if the antigen is encountered again there are now more immune cells around to counter it. That's the principle, but a simplification. Jmchutchinson (talk) 16:57, 14 February 2021 (UTC)
- Thank you both. That's a lot more reassuring. Still, autoimmune diseases triggered by (acute) infections do happen, meaning these protective mechanisms are not foolproof. I assume the bigger the inflammation--e.g., fever--the more likely it happens. At the least, the more acute infections/inflammations/fever-triggering vaccinations one experiences, the more likely something would go wrong. We now have 7 U.S. COVID-19 strains with a different commonality than the UK and S.A. strains, so it's highly likely that we'll need booster shots at least every year, a fever every year. That seems like a big toll on the body. It's been severa years since I've run a fever, for example. Imagine Reason (talk) 00:17, 15 February 2021 (UTC)
- It's honestly not that big a toll. People get annual shots for things like the flu shot all the time, and the vast (and I mean vast, as in close to 100%) majority of them don't have any ill effects at all. The fact is that our bodies are foreign invasion constantly. You are probably exposed to multiple different foreign microbes on the daily, and most of the time you do not even notice it. Your immune system takes care of them, including antigen recognition, fairly quickly and quietly (macroscopically speaking). This is why something like HIV or chemotherapy induced immune system suppression is so dangerous; the body's natural immune system ability to recognize and combat foreign invasion crashes to zero, and daily exposure goes from something you don't notice to something that can kill you. Furthermore, it's too soon to say that the presence of these different strains means we will need annual boosters. For many of these strains, the vaccines that have already been developed are effective across multiple strains, possibly all of them, at least to some degree. --OuroborosCobra (talk) 07:53, 15 February 2021 (UTC)
- Thank you both. That's a lot more reassuring. Still, autoimmune diseases triggered by (acute) infections do happen, meaning these protective mechanisms are not foolproof. I assume the bigger the inflammation--e.g., fever--the more likely it happens. At the least, the more acute infections/inflammations/fever-triggering vaccinations one experiences, the more likely something would go wrong. We now have 7 U.S. COVID-19 strains with a different commonality than the UK and S.A. strains, so it's highly likely that we'll need booster shots at least every year, a fever every year. That seems like a big toll on the body. It's been severa years since I've run a fever, for example. Imagine Reason (talk) 00:17, 15 February 2021 (UTC)
- That's my point, though. People don't get fevers from flu shots for the most part, nor from minor infections. The fact that most COVID-19 vaccines, esp. the most effective ones, result in an albeit short bout of fever means that the body is inflamed more than it usually is. Like I said, I get a flu shot every year precisely to avoid fevers. As for the prospect of booster shots, I'll just point to the fact that no vaccine has proven to be as effective on the South African strain as, and a few have proven to be much less effective than, on the older strains. Imagine Reason (talk) 12:30, 15 February 2021 (UTC)
- Your first statement is incorrect. Some people do get fevers after a flu shot. According to the Mayo Clinic, cited there, "Some people experience muscle aches and a fever for a day or two after receiving a flu vaccine. This may be a side effect of your body's production of protective antibodies." Something your response here indicates you don't understand is that "I don't get a fever" is not a synonym for "other people don't get a fever". --Jayron32 13:49, 15 February 2021 (UTC)
- I'm well aware of that. I said, "for the most part." I'm not sure, but I think it's a tenth of flu shots result in a fever, vs. about 3/4ths of the mRNA shots. COVID-19 is not the flu and COVID-19 vaccines are not flu shots, that much is clear. And I'm trying to decide about the shot for myself, not as a matter of public policy. On average, I don't expect to get a fever from a flu shot, but I do expect to get one from a COVID-19 shot. Imagine Reason (talk) 14:06, 15 February 2021 (UTC)
- A few things to consider: 1) The purpose of a vaccine is not merely to keep you from getting sick. It's to keep people in general from getting sick. Vaccination is not a purely personal decision, like "Will I eat spicy food today because I might get indigestion" and "do I want to go skiing, because it's a risky thing for me personally and there is a chance of injury". Vaccinations are only as effective as the number of people who get them, and it is not merely "personal risk" that matters. 2) The side effects reported have been mild compared to actually getting Covid-19. From anecdotal evidence from people I know, and from news reports I have been seeing, the general consensus is that it is generally 24-48 hours of a low-grade fever and aches, and then it goes away, if there is any side-effects at all. Actually getting Covid-19 is much, much worse, and carries significant risk of permanent health problems, up to and including death. --Jayron32 15:05, 15 February 2021 (UTC)
- I'm not going to base my decisions on what's best for the public, when the government has failed to protect my health for a year. If I'd listened to public health advice, I'd not have started buying masks in January 2020, masked up in March and moved my whole family to respirators by the end of that month. Believe me, I'm doing my part in keeping society from getting infected, but I'm not going to sacrifice my health in doing so. Yes, it'd be bad to get the disease, and that's why I'll get the vaccine if social isolation is no longer an option. That is not today though. Imagine Reason (talk) 00:12, 16 February 2021 (UTC)
- A short, temporary inconvenience, of which you have less than 20% chance of even experiencing, is not a sacrifice of your health. --Jayron32 12:47, 16 February 2021 (UTC)
- I'm not going to base my decisions on what's best for the public, when the government has failed to protect my health for a year. If I'd listened to public health advice, I'd not have started buying masks in January 2020, masked up in March and moved my whole family to respirators by the end of that month. Believe me, I'm doing my part in keeping society from getting infected, but I'm not going to sacrifice my health in doing so. Yes, it'd be bad to get the disease, and that's why I'll get the vaccine if social isolation is no longer an option. That is not today though. Imagine Reason (talk) 00:12, 16 February 2021 (UTC)
- (edit conflict)
On average, I don't expect to get a fever from a flu shot, but I do expect to get one from a COVID-19 shot
- why do you think the average person develops a fever? It's a fairly spectacular claim, which seems unlikely to me. From a quick check, I found this from the clinical trials for the Pfizer–BioNTech COVID-19 vaccine, fever was reported in 14.2% of participants [1] [2]. This which based on self-reports via an app in the UK probably has under 10% for fever [3]. (It's hard to say since I assume most people had fevers for more than one day, but probably not all days there, so you can just take the peak. There's also first dose vs second dose although frankly reactions to the first dose are so few that they probably don't significantly change the value.) And to be clear, these are fever after a COVID-19 vaccine. They aren't fevers from a COVID-19 vaccine. Nil Einne (talk) 00:22, 16 February 2021 (UTC)
- A few things to consider: 1) The purpose of a vaccine is not merely to keep you from getting sick. It's to keep people in general from getting sick. Vaccination is not a purely personal decision, like "Will I eat spicy food today because I might get indigestion" and "do I want to go skiing, because it's a risky thing for me personally and there is a chance of injury". Vaccinations are only as effective as the number of people who get them, and it is not merely "personal risk" that matters. 2) The side effects reported have been mild compared to actually getting Covid-19. From anecdotal evidence from people I know, and from news reports I have been seeing, the general consensus is that it is generally 24-48 hours of a low-grade fever and aches, and then it goes away, if there is any side-effects at all. Actually getting Covid-19 is much, much worse, and carries significant risk of permanent health problems, up to and including death. --Jayron32 15:05, 15 February 2021 (UTC)
- I'm well aware of that. I said, "for the most part." I'm not sure, but I think it's a tenth of flu shots result in a fever, vs. about 3/4ths of the mRNA shots. COVID-19 is not the flu and COVID-19 vaccines are not flu shots, that much is clear. And I'm trying to decide about the shot for myself, not as a matter of public policy. On average, I don't expect to get a fever from a flu shot, but I do expect to get one from a COVID-19 shot. Imagine Reason (talk) 14:06, 15 February 2021 (UTC)
- Your first statement is incorrect. Some people do get fevers after a flu shot. According to the Mayo Clinic, cited there, "Some people experience muscle aches and a fever for a day or two after receiving a flu vaccine. This may be a side effect of your body's production of protective antibodies." Something your response here indicates you don't understand is that "I don't get a fever" is not a synonym for "other people don't get a fever". --Jayron32 13:49, 15 February 2021 (UTC)
- That's my point, though. People don't get fevers from flu shots for the most part, nor from minor infections. The fact that most COVID-19 vaccines, esp. the most effective ones, result in an albeit short bout of fever means that the body is inflamed more than it usually is. Like I said, I get a flu shot every year precisely to avoid fevers. As for the prospect of booster shots, I'll just point to the fact that no vaccine has proven to be as effective on the South African strain as, and a few have proven to be much less effective than, on the older strains. Imagine Reason (talk) 12:30, 15 February 2021 (UTC)
- The premise of the question seems to be that Covid-19 mRNA vaccines cause statistically more fever side effects than other non-mRNA vaccines. It is possible but I would like to see evidence that this is true. In particular, one may need to correct for population characteristics - AFAICT mRNA Covid-19 vaccination occurs mostly in rich countries with a strategy of vaccinating the elderly first, and maybe (I have no idea) the elderly also have more fever reactions to vaccination in general. TigraanClick here to contact me 16:50, 15 February 2021 (UTC)
- Only a quarter of the Moderna trial subjects were seniors. This is not a surprise because drug trials tend to enroll healthy (and younger) subjects.[4] I'm trying to look up the detailed side effects breakdown I've seen before, but even seniors should expect to get hit by a fever after the second dose. I hope no one tries to convince me that a fever is nothing to worry about for seniors. Imagine Reason (talk) 00:12, 16 February 2021 (UTC)
- I'll be blunt here. Wherever you got your statistics from, I suggest you throw that source a way and never use it again. I had a look for the Moderna vaccine and sure enough, it's a similar thing. Even from the clinical trial, fever was only observed in 14.8% of participants after any dose. [5] The rate was a lot higher than placebo, so it seems the vaccine is somehow involved, but it's still very very far from the 50% you are claiming. (Any dose being 14.8% and dose 2 being 15.6% seems a little weird. I expect the explanation is a bunch of participants only received dose 1 for a variety of reasons.) Note also that both the Moderna and the BioNTech vaccines seems to have significantly higher adverse reactions, including fevers, after dose 2. So frankly, if someone is particularly worried about a fever for some odd reason, they're probably better off at least receiving the first dose. While this is pure speculation, I expect as with the BioNTech vaccine, fever rates reported in the community will be lower because people don't always detect a low grade fever. Nil Einne (talk) 00:38, 16 February 2021 (UTC)
- Yes, absolutely. Had the rate of fever after the second dose been 50%, getting one shot should be an option. Moderna side effects [6] Imagine Reason (talk) 01:15, 16 February 2021 (UTC)
- I'll be blunt here. Wherever you got your statistics from, I suggest you throw that source a way and never use it again. I had a look for the Moderna vaccine and sure enough, it's a similar thing. Even from the clinical trial, fever was only observed in 14.8% of participants after any dose. [5] The rate was a lot higher than placebo, so it seems the vaccine is somehow involved, but it's still very very far from the 50% you are claiming. (Any dose being 14.8% and dose 2 being 15.6% seems a little weird. I expect the explanation is a bunch of participants only received dose 1 for a variety of reasons.) Note also that both the Moderna and the BioNTech vaccines seems to have significantly higher adverse reactions, including fevers, after dose 2. So frankly, if someone is particularly worried about a fever for some odd reason, they're probably better off at least receiving the first dose. While this is pure speculation, I expect as with the BioNTech vaccine, fever rates reported in the community will be lower because people don't always detect a low grade fever. Nil Einne (talk) 00:38, 16 February 2021 (UTC)
- Only a quarter of the Moderna trial subjects were seniors. This is not a surprise because drug trials tend to enroll healthy (and younger) subjects.[4] I'm trying to look up the detailed side effects breakdown I've seen before, but even seniors should expect to get hit by a fever after the second dose. I hope no one tries to convince me that a fever is nothing to worry about for seniors. Imagine Reason (talk) 00:12, 16 February 2021 (UTC)
- My mistake. I must've conflated in my mind fever with other side effects. Pfizer side effects [7] I still maintain that if you're told you're going to get hit by a fever every year, you should be concerned. One more question. COVID-19 has a serious problem of causing autoimmune disorders. Can we dismiss the possibility that using SARS-CoV-2 proteins in a vaccine would not trigger autoimmune responses? Imagine Reason (talk) 01:07, 16 February 2021 (UTC)
- This video explains that such side effects are actually a sign of the vaccine working properly. --Lambiam 09:41, 16 February 2021 (UTC)
- Just because it's working doesn't mean it's not cost-free for the body. I was mainly concerned with fever; the other common side effects are generally less problematic. Imagine Reason (talk) 15:44, 16 February 2021 (UTC)
- You've yet to establish a cost for the body. --OuroborosCobra (talk) 16:30, 16 February 2021 (UTC)
- Just because it's working doesn't mean it's not cost-free for the body. I was mainly concerned with fever; the other common side effects are generally less problematic. Imagine Reason (talk) 15:44, 16 February 2021 (UTC)
- This video explains that such side effects are actually a sign of the vaccine working properly. --Lambiam 09:41, 16 February 2021 (UTC)
- "Fever was more common after the second dose and in the younger group (15.8%) compared to the older group (10.9%)" CDC - Local Reactions, Systemic Reactions, Adverse Events, and Serious Adverse Events: Pfizer-BioNTech COVID-19 Vaccine. That means that 85 or 90% of people don't get a fever. Note that a number of people reported a fever after receiving a harmless placebo. Alansplodge (talk) 12:30, 17 February 2021 (UTC)