“For the record,” RFK Jr writes in The Real Anthony Fauci (p. 485), “I believe that HIV is a cause of AIDS, but… causation is more complex than the official theology.” In a review of RFK Jr’s book, Chris Masterjohn wrote:

This is clear from the fact that only half of AIDS patients have HIV, that huge numbers of HIV-infected individuals never develop AIDS, and that non-HIV AIDS often occurs in patients with chronic fatigue syndrome (CFS), a connection never adequately followed up on. Kennedy takes no position on which of the alternative hypotheses are true, but describes a number that he believes clearly have enough merit to be investigated. These include the toxicity of nitrite “poppers,” heavily marketed by the pharmaceutical industry toward gays in the 1980s, the toxicity of AZT, used as a drug to treat HIV and supposedly delay the development of AIDS, other viruses such as human herpes virus 6 (HHV6), and mycoplasma. While Kennedy doesn't subscribe to the hypothesis that HIV is merely a free rider (maintained by Peter Duesberg), or that HIV is entirely generated from within human cells (maintained by Eleni Papadopulos and Val Turner), he believes these hypotheses should be acknowledged and considered.