Investigating Unconfirmed AIDS Claims: Aids Never Isolated or Photographed?

[Cyrus]

I heard this on the radio driving home. Apparantly this guy claims that Aids has never been isolated or photographed and that medical industries are diagnosing things as AIDs that is something else.

http://www.youtube.com/watch?v=HIX35HyQXg8&mode=related&search=

 

[chroot]

AIDS is a syndrome -- a disease -- not a pathogen.

The pathogen which is thought to cause AIDS, HIV, has been isolated and photomicrographed many, many times.

http://images.google.com/images?hl=en&q=HIV+photomicrograph&btnG=Search+Images&gbv=2

- Warren

 

[Cyrus]

Watch the second clip I provided by the PhD though.

Another PhD, http://www.youtube.com/watch?v=7qUBagW-xWs&mode=related&search=

 

[hypatia]

They have over 4,000 HIV testing sites in S Africa, with equipment provided by the WHO, UNAIDS and private funds. Despite what the PHD's say, there is large amount of people who have tested positive for HIV.
While deaths are explained as HIV related deaths, it has more to do with things like secondary infections. For example, bacterial or virus infection can kill someone with HIV, simply because they have very little ability to fight off the infections, even with medications. We here, in the states have people who die of HIV related disorders.
I am very sure, they{UNAIDS and WHO} know the difference between dysentery and starvation..and HIV

 

[Cyrus]

I want to hear moonbears take on the guy who talks about the photograph and all that other stuff. I am no biologist, so I can't take what he says as BS or fact - I know next to nothing when it comes to biology.

 

[russ_watters]

I want to hear moonbears take on the guy who talks about the photograph and all that other stuff. I am no biologist, so I can't take what he says as BS or fact - I know next to nothing when it comes to biology.

I'm no biologist either, but my take is that this has got to be one of the dumbest conspiracy theories of all time.*

[*caveat: Most conspiracy theories are among the dumbest of all time.]

 

[Cyrus]

http://www.youtube.com/watch?v=mZkrCm9wMKI&mode=related&search=

Parts II and III.

He makes some intersting points

http://www.youtube.com/watch?v=8l5IDC9bJyE&mode=related&search=

 

[Loren Booda]

AIDS being a conspiracy is more the reaction from a desperate and shamed underclass than medical fact.

 

[russ_watters]

He makes some intersting points

No, he makes stupid points.

-He denies the reality of African cultural sexual problems.
-He says that the symptoms seen are probably just the same flu, etc. seen in developed nations. Nevermind the actual HIV testing...
[I only got 2 minutes into it before I couldn't take any more]

Btw, you do realize that not all doctors are medical doctors, right? I don't know what his phd is in, but he's not a medical doctor, he's an African history teacher. Seems to me he suffers from an obvious case of bias.

In any case, he's missing his own point: it doesn't much matter what, specifically, is killing Africans by the millions. The fact of the matter is that it is happening and needs to be dealt with. Even if it actually is a flu strain that doesn't exist anywhere else and isn't detectable, we should still be trying to stop it.

 

[iansmith]

Tara at Aetiology (a blog at scienceblogs.com) regularly looks at the HIV and the claims of HIV deniers.

You should go through her archives on HIV
http://scienceblogs.com/aetiology/aidshiv/

 

[Moonbear]

I want to hear moonbears take on the guy who talks about the photograph and all that other stuff. I am no biologist, so I can't take what he says as BS or fact - I know next to nothing when it comes to biology.

I can't view any of the video clips, but I don't know why you're giving someone with a Ph.D. in history more weight than people with Ph.D.s studying microbiology/virology. If the gist of what they're saying is that HIV doesn't exist, then they're just crackpots, period.

If you're questioning that there are photomicrographs of the virus, here's the abstract of the article descriving them.

1: J Electron Microsc Tech. 1988 Jan;8(1):3-15.
Ultrastructure of human retroviruses.

Palmer E, Goldsmith CS.
Division of Viral Diseases, Centers for Disease Control, Atlanta, Georgia 30333.
We compared the ultrastructure of the human retroviruses by thin-section electron microscopy of infected lymphocytes. Virus particles form at the plasma membrane without involvement of a cytoplasmic precursor. Budding forms of human T-cell leukemia virus types I and II (HTLV-I and -II) consist of a crescent-shaped nucleoid separated from the envelope by an intermediate layer. Mature forms of these viruses are about 100 nm in diameter. The nucleoid is electron lucent and almost completely fills the virion. There is about a 10-nm space between the envelope and nucleoid. The envelope has fuzzy surface projections. HTLV-I and -II resemble other type C retroviruses in morphology. Budding forms of human immunodeficiency virus (HIV, LAV, HTLV-III) also have a crescent-shaped nucleoid but not an intermediate layer between the core and envelope. The envelope has rod-shaped surface projections. Mature forms of HIV have an electron-dense nucleoid that is eccentric and bar- or cone-shaped. Particles have the same ultrastructure as retroviruses of the Lentivirus genus. HIV is readily distinguishable from HTLV-I and -II by thin-section electron microscopy. HIV is usually found in extracellular spaces by transmission electron microscopy of thin sections, and scanning electron microscopy of HIV-infected T4 lymphocytes also shows many particles on the surface of these cells. Lymphadenopathy-associated virus type II (LAV-II) has the same internal ultrastructure as HIV, but its surface projections are more prominent, being about three times the length of those of HIV. Human T lymphotropic virus type IV (HTLV-IV) has the same morphology as LAV-II.

http://www.ncbi.nlm.nih.gov/sites/e...ez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSum

To elaborate on what Chroot already explained, HIV infects the immune system. AIDS is the syndrome describing when that infection has reached a stage in which is has disabled the immune system making the patient vulnerable to any and every pathogen around them...they are immunocompromised. Again, I don't know what the videos show because these clips all seem to just hang on me lately (not sure if there's a problem with youtube, the specific videos or my computer, or if they're just huge and I'm not patient enough to wait for them to load), but if any part of the argument is that people don't die from AIDS, that would be technically true...the HIV infection leading to AIDS is what made them vulnerable to everything else in the environment, and they die of whatever opportunistic infection they get that they can't fight off. Common pathogens in the environment that most people can fight off easily and have immunity against become deadly diseases for someone with AIDS.

 

[Cyrus]

The first guy has a PhD in biology. The second link has one in History.

This guy is Bio:
http://www.youtube.com/watch?v=HIX35HyQXg8&mode=related&search=

 

[Cyrus]

The first guy has a PhD in biology. The second link has one in History.

This guy is Bio:
http://www.youtube.com/watch?v=HIX35HyQXg8&mode=related&search=

Id like an explanation of what he's saying though. If no one has watched the video, I don't think its fair to criticize him. I want to know exactly what he's saying that's wrong. Not just that he's wrong.

 

[Cyrus]

In any case, he's missing his own point: it doesn't much matter what, specifically, is killing Africans by the millions. The fact of the matter is that it is happening and needs to be dealt with. Even if it actually is a flu strain that doesn't exist anywhere else and isn't detectable, we should still be trying to stop it.

I think because you only watched 2 minutes into the film, you missed his point. He said that AIDs needs to be critically evaluated in Africa because it might be a misdiagnosis and that many times when people die in Africa, they say its due to AIDS w/o doing a thurough autopsy. You should watch part II of the history guy before you criticize his words, because now your misquoting him.

 

[russ_watters]

My post contained no quotes, so I couldn't have misquoted him!

 

[TaraS]

Hi all,

Saw this in my referral logs and just thought I'd say a few things. First, as noted, Charlie Geshekter, the historian in the video (and indeed, many of those who were in the other videos--Kary Mullis, Duesberg, etc.) are all on the board of an HIV denial organization, Alive and Well.

http://www.aliveandwell.org/html/top_bar_pages/aboutus.html#ADBOARD

This was started by Christine Maggiore, and HIV+ individual whose daughter, Eliza Jane, died of AIDS. (Though they claim it was from a reaction to antibiotics, even though slides of her brain tested positive for HIV proteins). Note that none of them are infectious disease epidemiologists, and if their arguments about the epidemiology of HIV were held to each infectious organism, no microbe could be suggested to cause any disease. I can elaborate on this if you like, but that's their biggest problem.

Regarding AIDS in Africa, I wrote more about that here: http://scienceblogs.com/aetiology/2006/02/post_3.php , but the biggest problem with Geshekter's analysis is that he conflates simply having sex with developing AIDS--note the bait and switch? We know that people can have sex 20 times a day if they want, and they won't develop AIDS *unless they're infected with HIV.* So the issue isn't that the poor in Africa are having more sex than those who are wealthy--it's that the prevalence of HIV in the poor populations is much higher, so when they *do* have sex (especially with new partners), they can spread the virus, and thus AIDS is much more common in these populations. It's not just the sexual activity, as Geshekter would have you think researchers believe--it's sexual activity in those infected with HIV. So he's created a strawman, only to knock it down. Classic science denial.

As far as testing in Africa, yes, diagnosis of AIDS, especially in very impoverished areas, is often on symptoms rather than a molecular test. Again, Geshekter would have you believe this means that HIV doesn't cause AIDS. But think about it. What about the last time you went to your own physician and were diagnosed with influenza? What were the odds he did a molecular test? I'd guess about 50/50, and that's in a wealthy country. Physicians get pretty darn good at diagnosis based on symptoms alone, and in Africa, they do as well. A single bout of malaria or diarrhea won't cause a physician to suspect AIDS, even in Africa. It's when those are frequent, and accompanied by other signs (such as severe weight loss, etc.) that the physician begins to suspect AIDS.

Indeed, it's pretty rich that Geshekter chastises American science and Americans in general for attributing Africa's problems to AIDS, when essentially, he's saying that African doctors in Africa are too incompetent to even diagnose AIDS when their patient presents with it. African doctors have certainly noticed that contradiction, leading to articles such as this one: http://www.aegis.com/news/vv/2000/VV000701.html , where African doctors themselves note how ridiculous Geshekter's conclusions are (and how he also mischaracterizes their own research).

Finally, on HIV denial more broadly, it's interesting how even among themselves, the deniers can't agree. Does HIV even exist? Duesberg says absolutely; the Perth group says no way. Is AIDS then caused by drugs? Oxidation? Another virus? None of the above, all of the above? It's much like creationists arguing amongst themselves about the age of the Earth and common descent--they can't agree on anything except that the scientists are wrong.

I could say a lot more on these topics, but I'll stop there for now...

 

[Moonbear]

I think because you only watched 2 minutes into the film, you missed his point. He said that AIDs needs to be critically evaluated in Africa because it might be a misdiagnosis and that many times when people die in Africa, they say its due to AIDS w/o doing a thurough autopsy. You should watch part II of the history guy before you criticize his words, because now your misquoting him.

If they are already diagnosed as having AIDS, and an illness associated with AIDS, then why would a formal autopsy be required? As I stated above, you don't die of AIDS, per se, you'll die of the AIDS-associated infection, so how would it change the diagnosis of AIDS to find that someone died of TB, or pneumonia, or encephalitis? It's no different than someone on immunosuppressant drugs to prevent rejection of a transplant acquiring an infection and dying of it. The official cause of death would be the infection they acquired, but the reason they contracted the infection in the first place is that their immune system is suppressed by the drugs they are on.

By the way, I tracked down more info on Maniotis. I found another site with the video as well, and can't view it there either, but also tracked down a foundation he supports that seems to have discrediting the validity of AIDS tests as its premise. [Late edit: This is the same foundation to which TaraS refers above; she posted while I was working on this post...thanks for the added information TaraS.] From the information provided there, he must be quite the embarrassment to his department if he actually works in pathology and supports that foundation. They're challenging the early validation of the ELISA test because they say they don't actually show they can culture the virus from people with positive results for the antibody...but then go on to say they have "only" found the RNA or virus particles. HIV is a retrovirus. It's mostly RNA. Finding the RNA is quite conclusive. Beyond that, virus "particles" don't mean bits and pieces of virus, it's the term used when counting individual virions. So, they're refuting it because they simply don't know how to read a scientific paper.

: N Engl J Med. 1989 Dec 14;321(24):1621-5.Quantitation of human immunodeficiency virus type 1 in the blood of infected persons.

Ho DD, Moudgil T, Alam M.

Department of Medicine, UCLA School of Medicine, Cedars-Sinai Medical Center 90048.

We used end-point-dilution cultures to measure the level of infectious human immunodeficiency virus type 1 (HIV-1) in peripheral-blood mononuclear cells (PBMC) and plasma of 54 infected patients who were not receiving antiviral chemotherapy. HIV-1 was recovered from the plasma and PBMC of every seropositive patient, but from none of 22 seronegative control subjects. The mean titers in plasma were 30, 3500, and 3200 tissue-culture-infective doses (TCID) per milliliter for patients with asymptomatic infection, the acquired immunodeficiency syndrome (AIDS), and the AIDS-related complex, respectively. In PBMC, the mean titers were significantly higher for symptomatic patients (AIDS, 2200, and AIDS-related complex, 2700 TCID per 10(6) PBMC) than asymptomatic patients (20 TCID per 10(6) PBMC). The values for the symptomatic patients were considered to indicate that at least 1 in 400 circulating mononuclear cells harbored HIV-1. The HIV-1 titers of seven patients with AIDS or AIDS-related complex treated with zidovudine for four weeks decreased significantly in plasma but not in PBMC. In addition, the mean titer in the plasma of 20 patients receiving long-term zidovudine treatment (130 TCID per milliliter) was 25-fold lower than the mean for comparable untreated patients with AIDS or AIDS-related complex. We conclude that the levels of HIV-1 in plasma and PBMC are much higher than previous estimates. This high degree of HIV-1 viremia raises the possibility that the direct cytopathic effect of this retrovirus alone may be sufficient to explain much of the pathogenesis of AIDS.

http://content.nejm.org.www.libproxy.wvu.edu/cgi/content/abstract/321/24/1621

New England Journal of Medicine, 321 (24):1626-1631, 1989
Plasma viremia in human immunodeficiency virus infection
RW Coombs, AC Collier, JP Allain, B Nikora, M Leuther, GF Gjerset, and L Corey
Abstract

To determine which markers of human immunodeficiency virus type 1 (HIV) replication correlate most closely with progressive disease, we compared the following: (1) the frequency of isolation of HIV from peripheral-blood mononuclear cells (PBMC), (2) the frequency of isolation of the virus from cell-free plasma (plasma viremia), (3) the presence and titer of p24 antigen in plasma, and (4) the presence and titer of antibody to p24 antigen. We studied 213 persons who were positive for HIV antibody and 71 who were negative. HIV was isolated from PBMC from 207 of the 213 antibody-positive patients (97 percent), regardless of the clinical stage of the infection. Plasma viremia, in contrast, was correlated with the clinical stage of the infection. It was detected in 11 of 48 patients (23 percent) with asymptomatic infection, 32 of 71 (45 percent) in Class IVa of the Centers for Disease Control (those with AIDS-related complex), and 75 of 92 (82 percent) in Class IVc (those with AIDS) (P less than 0.01). Plasma HIV titers ranged from 10(0) to 10(4.3) and rose from a mean of 10(1.4) in asymptomatic patients to 10(2.5) in those with AIDS (P less than 0.02). Only 45 percent of patients with plasma viremia had HIV p24 antigen in either serum or plasma, and no correlation was found between the amount of p24 antigen in plasma and the plasma HIV titers. Follow-up tests indicated that plasma viremia was associated with a more marked decline in the CD4-lymphocyte cell count and the development of symptomatic disease (P = 0.034). We conclude that plasma viremia is a more sensitive virologic marker of the clinical stage of HIV infection and viral replication than the presence of p24 antigen or antibody in plasma. Not only whole blood but cell-free plasma from HIV-infected patients should be considered potentially infectious.

http://content.nejm.org.www.libproxy.wvu.edu/cgi/content/abstract/321/24/1626

The latter of these two seems to be the one frequently misquoted by the nutcases to claim there isn't enough HIV in infected individuals to account for disease (they often claim only about 10 virion were found), but that's only viruses present in SERUM (the liquid part of your blood), and more careful reading shows that that increases as symptomatic illness progresses. It also doesn't account for the much larger number of viruses found inside mononuclear blood cells, which are the part of the immune system compromised and targetted by the virus. And, in that case, all it takes is ONE virus particle in a cell to infect it.

From what I'm gathering about what these people are refuting, I think the best I can do is refer you back to the thread in General Discussion on strawman arguments.

 

[Cyrus]

This was started by Christine Maggiore, and HIV+ individual whose daughter, Eliza Jane, died of AIDS. (Though they claim it was from a reaction to antibiotics, even though slides of her brain tested positive for HIV proteins). Note that none of them are infectious disease epidemiologists, and if their arguments about the epidemiology of HIV were held to each infectious organism, no microbe could be suggested to cause any disease. I can elaborate on this if you like, but that's their biggest problem.

Hi Tara,

I see where you are going with this, but since I am not a Biology major, please do.

Also,

What do you say in response to his claim of lots of false positive testing used by clinical researchers in populations that are highly prone to giving false testing results, or the fact that testing positive for AIDs varies from country to country?

It's when those are frequent, and accompanied by other signs (such as severe weight loss, etc.) that the physician begins to suspect AIDS.

But given that these people live in poverty and may suffer from other conditions, isn't it imperative that testing be done to isolate what exactly is the cause of death or illness?

 

[Ivan Seeking]

He said that AIDs needs to be critically evaluated in Africa because it might be a misdiagnosis and that many times when people die in Africa, they say its due to AIDS w/o doing a thurough autopsy.

I've heard it argued that African nations often inflate the number of AIDS related deaths because in some sense funding is determined by the death rate.

 

[TaraS]

Hi Tara,

I see where you are going with this, but since I am not a Biology major, please do.

Sure. Many AIDS deniers, for example, use the aforementioned Christine Maggiore's life story as a case in point. She's tested HIV+, but as her organization notes, remains "alive and well." Therefore, HIV doesn't cause AIDS, because she's never developed AIDS.

Of course, if they took a broader picture of infectious disease epidemiology, they'd see how silly this is. With every pathogen known to man (with the possible exception of rabies), we know people who are infected but never develop disease symptoms. Look at tuberculosis, for example--approximately a third of the world is infected with this bacterium. However, only a small fraction of that go on to develop disease symptoms, and only a fraction of those die in any given year. To AIDS deniers, then, because many people carrying TB remain "alive and well," Mycobacterium tuberculosistherefore doesn't cause TB, right? Obviously that's incorrect, but that's one of their big arguments against the current "dogma" that HIV causes AIDS.

However, even medical science doesn't say that all people who are HIV+ will develop AIDS. We know of groups of people who have been HIV+ for years, yet are apparently just fine (even without antiretroviral drugs). These are known as "long-term nonprogressors," and are a group that's actively being studied to see just how they're holding the virus in check--what is it about them that keeps them OK, whereas other people succumb in just a few years if they're not treated? Again, where AIDS deniers sees a group like this and goes, "aha! These people aren't dying of AIDS, therefore HIV doesn't cause AIDS!", infectious disease epidemiologists, virologists, and immunologists see this as an expected outcome that we see with every other pathogen, and an opportunity to better understand the host/virus interaction.

Similarly, there are people who are repeatedly exposed to the virus, but never seroconvert. Why not? Deniers again cry foul with regard to HIV causation of AIDS, but meanwhile scientists have found factors (such as a mutation in the CCR5 gene, a protein on cells that helps the virus bind and invade host cells) that make a host resistant to infection in the first place. Again, these are things we'd expect with a broader understanding of infectious disease epidemiology, but deniers (wrongly) think it presents a challenge for the HIV/AIDS paradigm.

What do you say in response to his claim of lots of false positive testing used by clinical researchers in populations that are highly prone to giving false testing results, or the that testing positive for AIDs varies from country to country?

Again, this is something we see with all diagnostic tests (for any illness, be it cancer, infectious disease, autoimmune disease, etc. etc.)--no test is perfect. All have a rate of false positives or negatives associated with them. With HIV, that's why we use an original screening test, followed by a secondary (more specific) test. The first one will weed out most of the people who are negative (and do so fairly cheaply); the second (more expensive) test will confirm those who are positive.

Deniers like to say that there are all these conditions that will result in false positives. And indeed, a number have been reported in the literature--but do they mention that these reports are typically associated with *one case*? So while they say things like "there are 60 different conditions that have resulted in false positive results," that means that there have simply been ~60 (or heck, I'll be generous and even give them a few hundred) people, with certain conditions, whose condition has been associated with a false positive HIV test (and again, I'll note they are *associated* with this result--not necessarily *causal*). It's a big red herring, because again, we see this with pretty much every diagnostic test. But the HIV test is given to tens of millions of people, and the error rate is very small overall (for the ELISA, on the order of .2% give a false positive; for the Western confirmatory test, false positives occur more like .00001% of the time, with false negatives a bit more commonly at .001% of the time). This is a damn good test, and can additionally be followed up with RT-PCR to determine viral load (even more specific than the protein tests).

As far as differences between countries, I've tried to dig into that, but it's tough to find information out there on that which doesn't come from denialist websites. Different countries may use different confirmatory tests as well, so it's true that there's no universal, worldwide standard as far as HIV diagnosis. In the past, one commenter on my blog has posted standards around the world, and they're not nearly as different as HIV deniers would have you believe. Unfortunately it's tough to search comments and I'm apparently not using the right keyword to find that information right now.

But given that these people live in poverty and may suffer from other conditions, isn't it imperative that testing be done to isolate what exactly is the cause of death or illness?

In an ideal world, absolutely. However, the one thing I agree with the deniers on is that these countries are resource-poor, and there's simply not the funds available to do that for every person. Additionally, in some areas, there are cultural traditions that mean that doing autopsies or any kind of post-mortem work violates their beliefs. It's a tough area to work in, and this is why seroprevalence studies of living individuals are carried out instead--to get a snapshot of viral prevalence and disease in a particular area. It's not perfect, but coupled with some trust in the area physicians (as I mentioned previously) and their familiarity with the disease, it's probably as good as we're going to get for right now. (And in this context, keep in mind the thousands of people here in the US, with all our resources, that also die of undiagnosed causes...)

 

[G01]

To me the whole agrument of "not ever seeing an HIV virus, just the RNA,etc." is rubbish, considering the paper Moonbear cited.

I'm very skeptical about these videos for this reason and because I'm pretty sure in the first one, one lady call Africa a "country".

 

[LightbulbSun]

This is rubbish. Now let's deny air because WE CAN'T SEE IT!

 

[Cyrus]

This is rubbish. Now let's deny air because WE CAN'T SEE IT!

You can see air everyday, its called atmospheric perspective.

 

[Pakbabydoll]

WOW no way..., believe it HIV and AIDS are real..

 

[raolduke]

I thought that there are two precursors for HIV? I was lead to believe that african/american are more likely to have 1 of these prerequisites?

 

[Mallignamius]

-snip-

However, even medical science doesn't say that all people who are HIV+ will develop AIDS. We know of groups of people who have been HIV+ for years, yet are apparently just fine (even without antiretroviral drugs). These are known as "long-term nonprogressors," and are a group that's actively being studied to see just how they're holding the virus in check--what is it about them that keeps them OK, whereas other people succumb in just a few years if they're not treated?

-snip-

Long-term nonprogressors have been studied for years. Has there been any significant progress?

 

[adrenaline]

Long-term nonprogressors have been studied for years. Has there been any significant progress?

Their cell-mediated immunity is somehow different. Scientists are studying HIV-specific CD4+ Th1 lymphocyte levels and activity, high levels of which seem to the best factor linked to protection in these long term non progressors . I have a small population of these long term non progressors ( Hiv + individuals who maintain a CD4 count of 600 and above without antivirals for at least five years.) One stayed HIV + without progression for 20 years ! All his freinds who went on antiretrovirals died many years before him! He progressed rather quickly to AIDS towards the end of the twenty years and died of herpes encephalitis. He also had crippling rheumatoid and lupus. Off hand I know of three others in my practice who have maintained non progression along with their autoimmune diseases... almost as if their dysfunctional immune system that causes their body to attack their own organs ( lupus, rheumatid, ankylosing spondylitis, crohns disease etc.) simultaneously keeps their Aids virus in check! Interestingly, there is some data that genetic status such as HLA-B 27 individuals protect from AIDS rapid progression. (These HLA-B27 patients are also more prone to developing such autoimmune diseases that I have mentioned.)

I think right these non progressors are providing a wealth of information for those researchers working on vaccine development.

Anyway, back to the folks discrediting the Aids virus. What did they think was happening to these people's immune system that was making them die from things that just don't kill people with normal immunities, even under the most distressing physical conditions ( ie: starvation)? ( I'm talking about cryptococcal meningitis, toxoplasmosis, PCP pneumonia, etc.) Infections that were almost non existent until the AIDS epidemic. Of course they could try to argue about how these folks died from "normal infections" like cholera, streptococcal pneumonia, malaria etc which also kill non HIV infected folks, but how do they explain these opportunistic infections? MAC colitis ( Mycobacterium avium complex) diarrhea is almost unheard of in those with normal immune systems, and ok, maybe you can argue about chemotherapy induced immune dysfunction ( which predisposes these patients to some similar opportunistic infections found only in HIV) but I doubt that that many Africans are getting chemotherapy!

What do you say in response to his claim of lots of false positive testing used by clinical researchers in populations that are highly prone to giving false testing results, or the that testing positive for AIDs varies from country to country?

I can't do better than Tara on this but let me throw in my measly input. First of all, out of the thousands of medical diagnostic tests out there to diagnose any medical problem, the Aids test ( Elisa followed by western blot which amplifies HIV DNA) is the most sensitive and specific test out there. Tara was right, it's a damn good test in fact,we were taught in medical school that many other diagnostic testing out there don't come close to surpassing the AIDS test in its accuracy! The serum tests that look for Lupus or rheumatoid arthritis or syphllis doesn't even come close to the accuracy of the AIDS test. Why no "conspiracy" about rheumatoid arthritis or lupus or syphillis?

The rapid ELISA test has a sensitvity and specificity of over 99%. (The sensitivities and specificities close to 100% really make the test very reliable in the right clinical setting.) I don't know of any other medical diagnostic serum testing that is so sensitive or specific. . And yes there are false postives and negatives. However, if you look at the fact that the most common malaria test has only a sensitivity of 88% and specificity of 95 %, the malaria testing has a much higher rate of false positives! Hot dang, there must also be a conspiracy about the malaria epidemic!

 

[Mallignamius]

Thank you for the update.

For curiosity, what vectors are being considered for inducing cell-mediated immunity to HIV1? And have any vaccine candidates passed phase II yet?

 

[adrenaline]

Thank you for the update.

For curiosity, what vectors are being considered for inducing cell-mediated immunity to HIV1? And have any vaccine candidates passed phase II yet?

You better let a biologist answer the first half. as for phase III trial one was done in 1993 that was not too promising ( efficacy of 20% and the vaccine consisted of 7 shots, ouch!) here are the details

http://www.medscape.com/viewarticle/452480

I haven't really heard of any new ones down the pipe. I'll ask my ID folks here and post later.

 

[Curious3141]

the Aids test ( Elisa followed by western blot which amplifies HIV DNA)

The ELISA detects antibodies to HIV +/- p24 Antigen (in the case of 4th generation assays). It is a highly sensitive and highly specific assay, but is capable of giving significant numbers of false positives in a low prevalence population (where the pre-test odds are low). This is a common pitfall : low prevalence compromises positive predictive value in any test with less than 100% specificity.

The Western Blot (or immunoblot) detects specific antibodies to weight sorted HIV-1 proteins belonging to the 3 classes (gag, pol, env). It is a less sensitive but more specific assay than the ELISA, and is often used for confirmation and disease follow-up. The Western Blot pattern can be positive, negative or indeterminate and there are different criteria for reading them (CDC/ASTPHLD, American Red Cross, CRSS etc.) The pattern can evolve with disease progression. HIV-2 specific WBs are available.

Nucleic acid tests are the most sensitive, most specific and most expensive. They are difficult to perform with expertise (if done improperly, false negatives due to sample matrix inhibition and false positives due to sample-sample carryover contamination abound). They are uncommonly used in routine clinical diagnosis and are generally reserved for screening blood products prior to human transfusion. They are also sometimes useful in testing neonates with vertically acquired maternal antibodies to HIV. You can test for viral RNA or proviral DNA (which is the form that integrates into human cells). You can use different assay methodologies (PCR for DNA, RT-PCR for RNA and bDNA (branched chain DNA assay)).

 

[adrenaline]

The ELISA detects antibodies to HIV +/- p24 Antigen (in the case of 4th generation assays). It is a highly sensitive and highly specific assay, but is capable of giving significant numbers of false positives in a low prevalence population (where the pre-test odds are low). This is a common pitfall : low prevalence compromises positive predictive value in any test with less than 100% specificity.

The Western Blot (or immunoblot) detects specific antibodies to weight sorted HIV-1 proteins belonging to the 3 classes (gag, pol, env). It is a less sensitive but more specific assay than the ELISA, and is often used for confirmation and disease follow-up. The Western Blot pattern can be positive, negative or indeterminate and there are different criteria for reading them (CDC/ASTPHLD, American Red Cross, CRSS etc.) The pattern can evolve with disease progression. HIV-2 specific WBs are available.

Nucleic acid tests are the most sensitive, most specific and most expensive. They are difficult to perform with expertise (if done improperly, false negatives due to sample matrix inhibition and false positives due to sample-sample carryover contamination abound). They are uncommonly used in routine clinical diagnosis and are generally reserved for screening blood products prior to human transfusion. They are also sometimes useful in testing neonates with vertically acquired maternal antibodies to HIV. You can test for viral RNA or proviral DNA (which is the form that integrates into human cells). You can use different assay methodologies (PCR for DNA, RT-PCR for RNA and bDNA (branched chain DNA assay)).

very true which is why no medical test should be ordered unless the pretest probability for the disease is high and the local prevalence of the disease is taken into consideration. Ordering a HIV test in a virginal nun is probably not a good idea. ( ELisa with reflex western blot if positive). For that reason I don't order CA 125s at all for ovarian cancer screening, the sensitivey and specificity suck. However, compared to any singular medical diagnostic test I have yet to find any medical diagnostic test ( both serological as well as say, radiographic ( ex helical cat scan for pumonary embolism where senstiviites and specificities range from 57-95% and 78%-98% respectively depending on the study and type of cat scan) that comes close to the HIV test! There is no doubt under the right circumstance it can produce false positives and negatives but there is no other medical diagnostic test that I can recall offhand that has such a good specifcity and sensitvity ( Thus the potential to diagnose a blood clot in the lungs is fraught with much more false negatives and positives.) (I was sleep deprived yesterday so I meant to say DNA isolation vs amplification). Thats why this guy bringing up the rate of false positives and false negatives as the main thrust of his argument is way off base. He has no idea that almost all other medical diagnostic testing are far less sensitive and specific!

 

[Curious3141]

(I was sleep deprived yesterday so I meant to say DNA isolation vs amplification).

The Western blot is an immunologic (antibody) test. It is not a nucleic acid (DNA/RNA) assay at all.

I agree with the rest of the stuff about sens/spec. etc.

 

[adrenaline]

The Western blot is an immunologic (antibody) test. It is not a nucleic acid (DNA/RNA) assay at all.

I agree with the rest of the stuff about sens/spec. etc.

you are right, i keep thinking of pcr and my lack of sleep is making me3 punchy.