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I might have qualms with injecting myself with HIV, which is basically what a vaccine is doing (correct me if I am wrong).
Posts: 3134 | Registered: Mar 2005
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quote:Originally posted by Stephan: I might have qualms with injecting myself with HIV, which is basically what a vaccine is doing (correct me if I am wrong).
*blink* Go read about Jenner and cowpox. Then read a bit about modern vaccination.
Posts: 32919 | Registered: Mar 2003
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I'm curious to know if they have ever found any humans who have been exposed to the virus and not contracted the disease, or if there is a 100% infection rate which somehow (in my granted very unscientific mind) seems unlikely.
Posts: 4089 | Registered: Apr 2003
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quote:Originally posted by sarcasticmuppet: I'm curious to know if they have ever found any humans who have been exposed to the virus and not contracted the disease, or if there is a 100% infection rate which somehow (in my granted very unscientific mind) seems unlikely.
Yes. There is a known mutation that provides a large degree of resistance to the disease. The mutation in the CCR5 protein which prevents many strains of HIV from bonding with immune system cells.
Posts: 2437 | Registered: Apr 2005
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He might be asking about those people who are basically immune to HIV. I believe a group of Eastern Europeans with a mutation in a receptor (sorry, I am lazy and not feeling well, took a vicodin, so the name of the receptor is escaping me right now) are basically immune. The mutation is at higher rates then expected since it provided protection against like small pox of black plague or something that killed a lot of people in the past. Someone had a thread about it on hatrack I think.
ETA- drats ricree101 beat me and gave better info too. Posts: 2223 | Registered: Mar 2008
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quote:Originally posted by scholarette: The mutation is at higher rates then expected since it provided protection against like small pox of black plague or something that killed a lot of people in the past.
There was a lot of speculation that the mutation spread to a larger portion of the population because it provided some resistance to the black death. However, that wikipedia page I linked stated that this may not be the case. There is a study cited there that argues that bronze age distributions of this mutation were similar to modern distributions. Here is the abstract of the paper wikipedia references.
Posts: 2437 | Registered: Apr 2005
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[QUOTE]Originally posted by sarcasticmuppet: [QB] I'm curious to know if they have ever found any humans who have been exposed to the virus and not contracted the disease, or if there is a 100% infection rate which somehow (in my granted veMost of us have probably been exposed to it at this point. It is VERY hard to contract compared to most viruses.
There have been millions of needle sticks over the last 20 years, with needles that HAVE THE HIV VIRUS ON THEM, and the infection rate is below 30% even with direct blood to blood transfer.
Posts: 15082 | Registered: Jul 2001
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quote:Originally posted by Kwea: [QUOTE]Originally posted by sarcasticmuppet: [QB] I'm curious to know if they have ever found any humans who have been exposed to the virus and not contracted the disease, or if there is a 100% infection rate which somehow (in my granted veMost of us have probably been exposed to it at this point. It is VERY hard to contract compared to most viruses.
There have been millions of needle sticks over the last 20 years, with needles that HAVE THE HIV VIRUS ON THEM, and the infection rate is below 30% even with direct blood to blood transfer.
This says more about the difficulty of contracting the virus and the fragility of the virus than it does about a population with natural immunity, however.
Posts: 2069 | Registered: May 2001
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quote:Originally posted by Stephan: I might have qualms with injecting myself with HIV, which is basically what a vaccine is doing (correct me if I am wrong).
Vaccines are developed and manufactured in so many ways now, it's insane. I've seen a lot of stuff on some of them while doing litigation work that involves trade secrets, but they start with all sorts of things that are not necessarily the virus itself nor the human antibodies. That's about as far as my knowledge and understanding goes.
Posts: 691 | Registered: Nov 2008
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Yep! It's pretty amazing what we've come up with to protect ourselves from various diseases. As Rivka pointed out, the first vaccine -- for smallpox -- was a live, full-strength virus, albeit a much milder cousin to smallpox. In fact, the word vaccine comes from vaccinia, which is the name of the cowpox virus used to prevent smallpox.
Some vaccines do use live-attenuated viruses (LAV). These viruses are grown in cells from organisms they don’t usually infect. For example, the mumps vaccine was developed by growing mumps virus in chicken embryo cells. At first, the virus doesn’t grow very well in the unfamiliar host. Eventually, though, mutations occur that allow some of the viruses to grow much better in the chicken cells, and they out-compete the original virus. Do this long enough, and you end up with a virus strain that grows quite well in chickens. The same changes that allowed the virus to adapt to chicken cells make them less able to grow well in human cells. The mutated strain can then be used as a vaccine. It’s similar enough to the original virus to create immunity, but not similar enough to cause full-blown disease. LAV vaccines tend to be quite effective in inducing immunity. However the risk with such vaccines is that in rare cases, the virus could mutate back to the original form and cause the person to become sick. One problem with HIV is that it is very prone to mutation, and the risk might be unacceptably high. It’s possible that very high-risk individuals would be offered a live vaccine, but I doubt such a vaccine would ever come into common use.
Many vaccines contain viruses killed with heat or chemicals. There’s no danger of the virus causing an infection. Flu vaccine (except for the nasal spray) contains dead virus, which is why you can’t get the flu from it.
These days, though, most vaccines contain bits and pieces of viruses or bacteria, not the whole thing. Some vaccines are just the proteins from the viral coat (such as the HPV vaccine). Some of the attempts at HIV vaccines have used coat proteins. Some vaccines don’t protect against the organism, but against the toxins they produce. Tetanus is caused by a bacterium that releases a neurotoxin. The tetanus vaccine contains an inactivated version of the toxin.
An experimental type of vaccine uses DNA. Some genes from a virus are combined with sections of DNA that tell the cell to use the gene to make proteins. Because not all the genes are present, making the proteins won’t result in a viable virus. The potential advantage of DNA vaccination is a better immune response – the process mimics what happens when a virus infects a cell and might provoke a more thorough reaction – without the risk of actually causing the disease (the problem with LAV vaccines).
All this to say: No, an HIV vaccine would probably not involve injecting yourself with HIV.
Posts: 3546 | Registered: Jul 2002
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quote:Originally posted by Stephan: I might have qualms with injecting myself with HIV, which is basically what a vaccine is doing (correct me if I am wrong).
*blink* Go read about Jenner and cowpox. Then read a bit about modern vaccination.
Isn't one of the polio vaccinations a weakened version of the virus? I'm fairly certain my little sister got that one. You can bet that by the time any vaccine gets to the American public, there will be very very little chance of you getting the disease from it, if it's the live kind. Besides, if there's any justice in the world, the first versions will be going to little children in Africa and most of the production resources will be spent making it for them.
Posts: 1757 | Registered: Oct 2004
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quote:Originally posted by theamazeeaz: Isn't one of the polio vaccinations a weakened version of the virus? I'm fairly certain my little sister got that one. You can bet that by the time any vaccine gets to the American public, there will be very very little chance of you getting the disease from it, if it's the live kind. Besides, if there's any justice in the world, the first versions will be going to little children in Africa and most of the production resources will be spent making it for them.
There are several attenuated live viruses in use today - Measles, Mumps & Rubella (MMR), Varicella (chicken pox) and Live Attenuated Influenza Vaccine (LAIV or Flu-mist, which is administered in the nose as opposed to an injection). While there are issues associated with these vaccines (you shouldn't have them within 6 weeks of each other and (almost) never before 12 months of age for example), the risk of actually contracting the disease from them is extremely negligible.
As for Polio, I'd have to look up how long it's been since the live vaccine was recommended in the US, but today a killed vaccine is used. My youngest child is 17, and when she got her last booster, about 1996, she received the live formulation. The live (attenuated) vaccine was administered by mouth, and the killed vaccine is injected, so you would know which you had.
Posts: 2069 | Registered: May 2001
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quote:Originally posted by Kwea: [QUOTE]Originally posted by sarcasticmuppet: [QB] I'm curious to know if they have ever found any humans who have been exposed to the virus and not contracted the disease, or if there is a 100% infection rate which somehow (in my granted veMost of us have probably been exposed to it at this point. It is VERY hard to contract compared to most viruses.
There have been millions of needle sticks over the last 20 years, with needles that HAVE THE HIV VIRUS ON THEM, and the infection rate is below 30% even with direct blood to blood transfer.
This says more about the difficulty of contracting the virus and the fragility of the virus than it does about a population with natural immunity, however.
Right....but I was addressing the question of contracting it by/with direct exposure.
Posts: 15082 | Registered: Jul 2001
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One of my mother's best friends contracted polio as a little girl when she was about 5 years old by drinking from a horse trough. She was one of Sulk's original patients, and she was one of the people who helped him develop the first polio vaccination.
They remained in contact until his death, actually.
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