5 ms·

I really doubt the "no human interpretation" part of the Engadget article. I've been involved in HIV education as part of the gay community, and this sort of ki

by ikarous 15y ago

I really doubt the "no human interpretation" part of the Engadget article. I've been involved in HIV education as part of the gay community, and this sort of kit worries me greatly. If the test is an antibody based test, then it could do far more harm than good by giving uneducated users a false sense of security: a negative result does not mean that you don't have HIV. While I'm sure that everyone on HN understands the seroconversion window period, this is simply not the case in the larger community. Ignorance about HIV is widespread. I cannot even begin to count the number of people who believe that pulling out before ejaculating affords some sort of magical protection from the virus. These are the same people who upon seeing a negative result would assume that they're safe without condoms. The CDC states that the window period for detectable HIV antibody formation is three months; however, this figure is based on first generation HIV tests and is considered somewhat conservative. Public health experts like H. Hunter Handsfield state that detectable antibodies usually form in four to six weeks. Whatever figure you choose to believe, it's a pretty significant time period. And it's a deadly one. It's during the window period that an HIV infected person is most infectious. Their viral loads are off the chart and they can unknowingly infect multiple people in a short period of time. The "cure" for HIV is the same as it has always been: education and safer sex practices. HIV is largely a preventable disease. I would be okay with personal test kits if they were bundled with extremely clear educational packets printed in multiple languages. But this particular kit is advertised too much like a silver bullet to assure me that the manufacturers are anywhere near that responsible.

mrspandex 15y ago
>> While I'm sure that everyone on HN understands the seroconversion window period... I don't. Care to explain?
- wrl 15y ago
  Usually, an HIV test doesn't test for presence of the virus itself; it tests for the antibodies your immune system develops in response to infection. The "window period" is the span of time between contracting the virus and the presence of detectable antibodies, which can be up to 6 months in some cases (though it's usually shorter). During this period, a person will test negative for HIV even though he or she is infected with the virus (and, worse, is contagious). Newer tests have been developed that test for presence of the virus's RNA, shortening the window period to about 21 days (if I recall correctly), but they are more expensive and much, much less widespread.
  - latch 15y ago
    thanks for the explanation. it worries me that anyone thinks this is common knowledge amongst a more-or-less programmer community. It worries me even more that perhaps it is, and I'm just ignorant.
    - carbocation 15y ago
      Any time I see a comment like yours, the correct response to your question is almost always, "It's a system problem." If we aren't effectively disseminating knowledge about an important public health risk, we're not putting ourselves in a winning position.
    - Shenglong 15y ago
      This was taught in my school system, but not in such depth. They focused on prevention, rather than recognition, and we had to rely on old faithful Wikipedia to tell us the rest.
    - araneae 15y ago
      An additional piece of information- you're approximately 4,000% more likely to transmit HIV during this early stage infection because of this high viral load. Some research estimates as much as 50% of all new infections come from people in this early infectious window.
      - rdl 15y ago
        Whoa. I knew about the window, but NOT that it was much more contagious during the early window. Thank you!
        gmazzotti 15y ago
        Here is an excellent video that explain in detail this that in the early stages it is much more contagious http://www.ted.com/talks/elizabeth_pisani_sex_drugs_and_hiv_let_s_get_rational_1.html http://www.ted.com/talks/elizabeth_pisani_sex_drugs_and_hiv_... and others IMPORTANT commonly unknow details that change totally how to fight to the virus.
- deleted 15y ago
  [deleted]
carbocation 15y ago
It's not good public health to deny information to everyone because some people will misuse said information. While the linked rag's piece is sensationalized, the Nature Medicine article on this device is more useful. http://www.nature.com/nm/journal/vaop/ncurrent/full/nm.2408.html http://www.nature.com/nm/journal/vaop/ncurrent/full/nm.2408....
- ikarous 15y ago
  I am not at all opposed to providing information! I merely want the test to come with very easy to understand instructions so that people know what results really mean.
  - sorbus 15y ago
    > I merely want the test to come with very easy to understand instructions so that people know what results really mean. Do you see any evidence that it will not?
    - ikarous 15y ago
      Do you see any evidence that it will? I don't need evidence either way to state that I prefer for it to be distributed with such information. If it is, then that's great.
      - sorbus 15y ago
        All I see is that this isn't in large-scale production yet (though chips do exist and have been verified to work), and likely won't be marketed to the general public. Preferring it to be distributed with information is great - I entirely agree with that - I'm just trying to point out that your reasons for expecting it not to include that ("this particular kit is advertised too much like a silver bullet to assure me that the manufacturers are anywhere near that responsible") make no bloody sense. This isn't advertising, this is a report on a study that was published in Nature (so why should we care what some reporter characterizes it as?), and there are no manufacturers yet.
alexholehouse 15y ago
Couldn't agree more (hence my post) - although nutrition may play a role in the antibody response. Malnourished individuals (especially those with low protein diets) tend to show slower antibody responses, so may have a longer seronconversion window period
orc 15y ago
"Researchers at Columbia University claim the mChip has a 100 percent detection rate, although there's a four to six percent chance of getting a false positive" That sounds like a negative result DOES mean you don't have it, but a positive result DOESNT mean you do. Edit: I guess this is just misleading and you actually can get false negatives.
- deleted 15y ago
  [deleted]
- alexholehouse 15y ago
  A negative result DOES mean there are not detectable levels of antibodies. However, while obviously highly linked this is NOT the same as saying you don't have it. They're correct to say it has a 100% detection rate (assuming it does, but we have no reason to suspect otherwise), but I think this is quite misleading - it's detecting HIV-specific antibodies, not the virus itself.
  - orc 15y ago
    Wow. Yeah, that's pretty misleading. Hope they have a big warning label to go with it.
- wrl 15y ago
  Better false positives than false negatives. Generally, after testing positive for HIV, there are follow-up tests done to verify the result (usually with a different test from the first) and to check for t-cell count (to determine how damaged the immune system is).
- abeppu 15y ago
  Does anyone here know anything about what goes into creating a test with a 0% false negative rate? That sounds impressive (even with the noted caveats that it's detecting the antibodies and not the virus).
  - stick 15y ago
    Making a test with 0% false negative rate is a piece of cake: if (test_taken == true) { test_result = true; } No negatives means no false negatives. ;) But seriously, this is the classic trade-off between high sensitivity (no false negatives) and high specificity (essentially no false positives). Usually, the lower you set your threshold for detection the more likely you are to tell some people they have the disease when they actually don't. Where you set that bar depends on what you're trying to accomplish and forces you consider the harms associated with telling people they have disease when they don't or missing disease in someone who does.
alexholehouse 15y ago
All this said, I think it's role is a not to be a "check if someone is clean for sexytime" test (incidentally, probably not a good tagline). Instead, it's a cheap, easy and effective way to test people (especially pregnant women) so they can begin a medical regime, rather than not having any realistic means to test and risk further spread and health damage.
- pbhjpbhj 15y ago
  Your comment sounds like someone saying at the advent of the pill that it was not about enabling promiscuity but about allowing wives to manage their family planning better.
araneae 15y ago
Thanks for playing this role on HN. I've responding to people on engadget to this effect; it really worries me that there are so many comments like "no more condoms for me!" The irony is that such a technology could easily worse the epidemic in the U.S. because of such ignorance.
Alex3917 15y ago
"HIV is largely a preventable disease." Except when the government is responsible for spreading the disease. 50% of all new infections come from intravenous drug use, and an even larger percentage are secondary to drug users. If you're gay then it's not illegal to use condoms, but if you're a heroin user then you can literally get put in jail for trying to use clean needles. What's more, many black communities in the US have higher HIV rates than sub-Saharan Africa. Why? Because so many black males are in prison that it completely changes the sexual dynamics for everyone left on the outside. And further, many of those in prison contract the virus and then end up spreading it throughout the larger community once they get released.
- rkalla 15y ago
  --------------- but if you're a heroin user then you can literally get put in jail for trying to use clean needles. --------------- Many pharmacies have programs for drug users to buy clean needles, no-questions-asked for exactly this reason. I am not negating what you said, I'm am sure there are elements of the program (or accessibility) that make it a less-than-perfect solution, but it does exist.
  - VladRussian 15y ago
    >Many pharmacies have programs for drug users to buy clean needles, no-questions-asked for exactly this reason. unfortunately, not being a drug user i couldn't benefit from it. Once i needed to buy a syringe, and when i'd ask for it (it was here in Bay Area), they would make big eyes and refuse. Surprised, i tried a couple other places - the same. Until, at another place, they sold it to me and made sure that it packed so when i'm walking to the car, it wouldn't be visible.
- stanmancan 15y ago
  Where I live in Canada we have clinics where people can get clean needles / properly dispose of used ones.
- joegaudet 15y ago
  Vancouver (where I live right now) has several needle exchanges, as well as, safe injection sites. I was reading yesterday that coastal health is releasing a free crack pipe + cleaner kit. Granted we are likely a bit more progressive then the rest of the country.

by ikarous 15y ago

mrspandex 15y ago

>> While I'm sure that everyone on HN understands the seroconversion window period... I don't. Care to explain?

wrl 15y ago
Usually, an HIV test doesn't test for presence of the virus itself; it tests for the antibodies your immune system develops in response to infection. The "window period" is the span of time between contracting the virus and the presence of detectable antibodies, which can be up to 6 months in some cases (though it's usually shorter). During this period, a person will test negative for HIV even though he or she is infected with the virus (and, worse, is contagious). Newer tests have been developed that test for presence of the virus's RNA, shortening the window period to about 21 days (if I recall correctly), but they are more expensive and much, much less widespread.
- latch 15y ago
  thanks for the explanation. it worries me that anyone thinks this is common knowledge amongst a more-or-less programmer community. It worries me even more that perhaps it is, and I'm just ignorant.
  - carbocation 15y ago
    Any time I see a comment like yours, the correct response to your question is almost always, "It's a system problem." If we aren't effectively disseminating knowledge about an important public health risk, we're not putting ourselves in a winning position.
  - Shenglong 15y ago
    This was taught in my school system, but not in such depth. They focused on prevention, rather than recognition, and we had to rely on old faithful Wikipedia to tell us the rest.
  - araneae 15y ago
    An additional piece of information- you're approximately 4,000% more likely to transmit HIV during this early stage infection because of this high viral load. Some research estimates as much as 50% of all new infections come from people in this early infectious window.
    - rdl 15y ago
      Whoa. I knew about the window, but NOT that it was much more contagious during the early window. Thank you!
      - gmazzotti 15y ago
        Here is an excellent video that explain in detail this that in the early stages it is much more contagious http://www.ted.com/talks/elizabeth_pisani_sex_drugs_and_hiv_let_s_get_rational_1.html http://www.ted.com/talks/elizabeth_pisani_sex_drugs_and_hiv_... and others IMPORTANT commonly unknow details that change totally how to fight to the virus.
deleted 15y ago
[deleted]

carbocation 15y ago

It's not good public health to deny information to everyone because some people will misuse said information. While the linked rag's piece is sensationalized, the Nature Medicine article on this device is more useful. http://www.nature.com/nm/journal/vaop/ncurrent/full/nm.2408.html http://www.nature.com/nm/journal/vaop/ncurrent/full/nm.2408....

ikarous 15y ago
I am not at all opposed to providing information! I merely want the test to come with very easy to understand instructions so that people know what results really mean.
- sorbus 15y ago
  > I merely want the test to come with very easy to understand instructions so that people know what results really mean. Do you see any evidence that it will not?
  - ikarous 15y ago
    Do you see any evidence that it will? I don't need evidence either way to state that I prefer for it to be distributed with such information. If it is, then that's great.
    - sorbus 15y ago
      All I see is that this isn't in large-scale production yet (though chips do exist and have been verified to work), and likely won't be marketed to the general public. Preferring it to be distributed with information is great - I entirely agree with that - I'm just trying to point out that your reasons for expecting it not to include that ("this particular kit is advertised too much like a silver bullet to assure me that the manufacturers are anywhere near that responsible") make no bloody sense. This isn't advertising, this is a report on a study that was published in Nature (so why should we care what some reporter characterizes it as?), and there are no manufacturers yet.

alexholehouse 15y ago

Couldn't agree more (hence my post) - although nutrition may play a role in the antibody response. Malnourished individuals (especially those with low protein diets) tend to show slower antibody responses, so may have a longer seronconversion window period

orc 15y ago

"Researchers at Columbia University claim the mChip has a 100 percent detection rate, although there's a four to six percent chance of getting a false positive" That sounds like a negative result DOES mean you don't have it, but a positive result DOESNT mean you do. Edit: I guess this is just misleading and you actually can get false negatives.

deleted 15y ago
[deleted]
alexholehouse 15y ago
A negative result DOES mean there are not detectable levels of antibodies. However, while obviously highly linked this is NOT the same as saying you don't have it. They're correct to say it has a 100% detection rate (assuming it does, but we have no reason to suspect otherwise), but I think this is quite misleading - it's detecting HIV-specific antibodies, not the virus itself.
- orc 15y ago
  Wow. Yeah, that's pretty misleading. Hope they have a big warning label to go with it.
wrl 15y ago
Better false positives than false negatives. Generally, after testing positive for HIV, there are follow-up tests done to verify the result (usually with a different test from the first) and to check for t-cell count (to determine how damaged the immune system is).
abeppu 15y ago
Does anyone here know anything about what goes into creating a test with a 0% false negative rate? That sounds impressive (even with the noted caveats that it's detecting the antibodies and not the virus).
- stick 15y ago
  Making a test with 0% false negative rate is a piece of cake: if (test_taken == true) { test_result = true; } No negatives means no false negatives. ;) But seriously, this is the classic trade-off between high sensitivity (no false negatives) and high specificity (essentially no false positives). Usually, the lower you set your threshold for detection the more likely you are to tell some people they have the disease when they actually don't. Where you set that bar depends on what you're trying to accomplish and forces you consider the harms associated with telling people they have disease when they don't or missing disease in someone who does.

alexholehouse 15y ago

All this said, I think it's role is a not to be a "check if someone is clean for sexytime" test (incidentally, probably not a good tagline). Instead, it's a cheap, easy and effective way to test people (especially pregnant women) so they can begin a medical regime, rather than not having any realistic means to test and risk further spread and health damage.

pbhjpbhj 15y ago
Your comment sounds like someone saying at the advent of the pill that it was not about enabling promiscuity but about allowing wives to manage their family planning better.

araneae 15y ago

Thanks for playing this role on HN. I've responding to people on engadget to this effect; it really worries me that there are so many comments like "no more condoms for me!" The irony is that such a technology could easily worse the epidemic in the U.S. because of such ignorance.

Alex3917 15y ago

"HIV is largely a preventable disease." Except when the government is responsible for spreading the disease. 50% of all new infections come from intravenous drug use, and an even larger percentage are secondary to drug users. If you're gay then it's not illegal to use condoms, but if you're a heroin user then you can literally get put in jail for trying to use clean needles. What's more, many black communities in the US have higher HIV rates than sub-Saharan Africa. Why? Because so many black males are in prison that it completely changes the sexual dynamics for everyone left on the outside. And further, many of those in prison contract the virus and then end up spreading it throughout the larger community once they get released.

rkalla 15y ago
--------------- but if you're a heroin user then you can literally get put in jail for trying to use clean needles. --------------- Many pharmacies have programs for drug users to buy clean needles, no-questions-asked for exactly this reason. I am not negating what you said, I'm am sure there are elements of the program (or accessibility) that make it a less-than-perfect solution, but it does exist.
- VladRussian 15y ago
  >Many pharmacies have programs for drug users to buy clean needles, no-questions-asked for exactly this reason. unfortunately, not being a drug user i couldn't benefit from it. Once i needed to buy a syringe, and when i'd ask for it (it was here in Bay Area), they would make big eyes and refuse. Surprised, i tried a couple other places - the same. Until, at another place, they sold it to me and made sure that it packed so when i'm walking to the car, it wouldn't be visible.
stanmancan 15y ago
Where I live in Canada we have clinics where people can get clean needles / properly dispose of used ones.
joegaudet 15y ago
Vancouver (where I live right now) has several needle exchanges, as well as, safe injection sites. I was reading yesterday that coastal health is releasing a free crack pipe + cleaner kit. Granted we are likely a bit more progressive then the rest of the country.