Infectious Disease Postdoc/Clinician
Department of Pediatrics, University Hospital, Syracuse, NY
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I would argue that the lack of a "white heterosexual epidemic" of HIV in the developed world is largely due to an effective public education campaign in the 1980's, and the fact that the virus entered the population through a sexually distinct risk group (homosexuals). This argument is rather like saying MI5 is useless because there haven't been any major terrorist activities in London in the last year!
All Dr Giraldo has shown is that if one performs the test incorrectly the results are meaningless. This has been discussed here before, and the fact that serum dilutions are frequently performed for other infectious diseases. It is an illogical argument.
Two large questions arise from Mr Russell's continual assertation that HIV is endogenous:
If that were so, wouldn't we expect a "white heterosexual epidemic" regardless of public health campaigns?
If that were so, wouldn't HIV DNA be found in all cells of all human beings, rather than only some cells in HIV+ human beings?
As regards sexual transmission, I refer Mr Russell to the work of McMichael and others with the HIV-resistant prostitutes in Nairobi. Of interest isn't the fact that a small number of these women refused to seroconvert after 10 years or more of exposure , or even that this was correlated with abnormal anti-HIV immune responses , but that if these women _lost_ their immune responses then they later acquired HIV infection within a few years, in line with the rest of the prostitute cohort .
Looks suspiciously like sexual transmission to me, and nothing at all like an endogenous phenomenon.
Can Mr Russell explain why a _reduction_ in high risk behaviour, associated with a decline in anti-HIV immune responses, should result in an increased expression of an endogenous phenomenon? One was under the impression that it was these behaviours that caused the expression of the endogenous elements! It seems more plausible that the immune responses were protective against an exogenous, sexually transmitted infection.
Mr Russell can say that the predictions haven't been fulfilled, but that is just his opinion, rather than the facts. I repeat: HIV serology precedes AIDS, specifically chronic CD4 T cell decline. HIV serology predicts HIV detection via other means (e.g. culture, PCR, antigen testing). Pharmacological intervention against the virus inhibits the viral replication in vitro and in vivo, and results in restoration of the immune dysfunction seen in AIDS and pre-AIDS complex patients. HIV serology also appears to be transmissible and associates with the individuals and risk groups associated with AIDS.
None of the above would be true if HIV were an endogenous entity.
Nick Bennett email@example.com
Refs: 1. Kaul et al J Immunol. 2000 Feb 1;164(3):1602-11. "HIV-1-specific mucosal CD8+ lymphocyte responses in the cervix of HIV-1-resistant prostitutes in Nairobi."
2. Kaul et alJ Clin Invest. 2001 May;107(10):1303-10. "CD8(+) lymphocytes respond to different HIV epitopes in seronegative and infected subjects."
3. Kaul et al J Clin Invest. 2001 Feb;107(3):341-9. "Late seroconversion in HIV-resistant Nairobi prostitutes despite pre-existing HIV-specific CD8+ responses."
Competing interests: None declared