American Scientist

To the Editors:

In "The Puzzling Origins of Aids" (November-December), Jim Moore provides a commendably fair analysis.   However, he neglects important evidence that I have reported since initial publication of The River in 1999. For example, the CHAT vaccine lot used in the 1958 trial of Koprowski's vaccines, involving 215,504 persons in the Ruzizi Valley (bordering the then Belgian Congo) was three times stronger when administered in Africa than when prepared at Philadelphia's Wistar Institute.  As live polio vaccines lose titre (concentration) during storage and transportation, the only conceivable explanation is that the researchers were passaging vaccine in locally available primate tissue cultures after arrival to boost quantity and titre—common practice at the time  (according to 2003, Atti dei Convegni Lincei 187: 27-230).  Belgians and Congolese who worked at the Stanleyville Medical Laboratory (the headquarters for the CHAT trials in Africa) attest that chimpanzee tissue cultures were frequently prepared there, and given to the head of virology, who was handling the polio vaccines.

Geneticists M.H. Schierup and R. Forsberg (2003, Atti dei Convegni Lincei 187: 231-245), present strong evidence indicating that recombination occurred early in the evolutionary history of HIV-1. This could have happened when two chimpanzee SIVs recombined in culture during CHAT preparation in chimp cells in Stanleyville. Schierup concludes that this alone could have engendered the global diversity of HIV-1 seen today.   Such a scenario would invalidate both the major arguments against OPV—the phylogenetic dating argument (that HIV-1 dates from 1931) and the "wrong subspecies" argument. The OPV theory can also account for the recent AIDS outbreaks caused by HIV-2 and the minor strains of HIV-1. Experimental polio vaccines (both oral and injected) prepared in African primate tissues were tested in French Equatorial Africa and French West Africa in the latter half of the 1950s. As detailed in the postscript to The River (2000 paperback version), these are the very places where the minor AIDS outbreaks occurred, and among the primates then being used by the French were chimpanzees and sooty mangabeys, the natural hosts to the immediate ancestors of HIV-1 and HIV-2.

Edward Hooper
Bridgwater, U.K.

Dr. Moore responds:

I thank Ed Hooper for his kind words about fairness; the topic is a minefield and I am pleased to have made it across (so far). I indeed neglected much "evidence" on every side of each theory,as well as entire theories. The problem is that the term evidence covers everything from physical blood samples to things that "could have happened" or that rely on testimonial juxtapositions: Hooper reports that people say that something was done with chimpanzee tissue cultures, and one of the people involved was (also?) involved with OPV work. The tenuous nature of such evidence greatly weakens the OPV scenario, and has been taken by some as "proof" that the theory is dead. While I believe the OPV theory is highly unlikely to be correct, that final judgment is premature. And there remains the still open question of exactly what was being done with the hundreds of chimpanzees at Camp Lindi.