Report from the AIDS/Poliovirus Advisory Committee

ONFIDENTIAL
Summary and recommendation
It is apparent that we consider the probability of the AIDS epidemic having
been started by the inadvertent inoculation of an unknown HIV precursor into
African children during the 1957 poliovirus vaccine trials to be extremely low.
Almost every step in this hypothetical mode of transmission is problematic. The
contamination of the poliovirus vaccine lots with SIV/HIV particles, if any, is likely
to have been extremely small. Transmission by the oral route is extremely rare for
HIV or SIV. Finally, the evolutionary distance between known monkey
immunodeficiency viruses and HIV-1, the prevalent virus in the AIDS epidemic,
probably took decades or centuries to be bridged and not a few years. The most
telling evidence is the case of the Manchester sailor who appears to have been
infected with HIV-1 even before the poliovirus trials were begun in Congo.
Such considerations notwithstanding, we feel that some testing of available
samples may be desirable so that no stone is left unturned. We are pessimistic that
such testing, even if performed by the best labs using the most appropriate
techniques, will produce conclusive results. Nevertheless, a limited number of
samples of vaccine stocks available at the Wistar Institute could be tested for the
presence of HIV/SIV viruses or related nucleic acid sequences. Of the samples
presently existing at the Wistar Institute, only one has been identified as being
possibly directly relevant to the Congo trials. Several other samples were prepared
around those times, but may never have been used in the 1957 vaccine trials. In
sum, the total number of samples (also considering the amount of material
available) worth testing is quite limited.
Testing should be done by, or under the direct supervision of, the World
Health Organization (WHO) or the U.S. Centers for Disease Control (CDC). Coded
samples should be tested in at least two experienced laboratories. Testing for the
presence of infectious SIV or HIV particles should be done using the following
target cells:
- Human peripheral blood lymphocytes cultures
- African green monkeys PBL cultures from SIV negative Caribbean
Monkeys
- the MoLT-4 clone 8 cell line
- the HUT78 cell line

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