Jay Levy, director of the Laboratory for Tumor and AIDS Virus Research at the University of California, San Francisco, writes in the January 11 edition of The Lancet that despite dire reports of HIV superinfection, it has not been proved that superinfection automatically results in a worsening of clinical outcome. In fact, he writes that it is common to simultaneously carry several different strains of viruses, such as Epstein-Barr and cytomegalovirus.
'In addition, there is a general misconception that once recovering from infection by measles, mumps, or chicken pox viruses, a person cannot be reinfected,' he writes. 'These viruses can reinfect but do not remain in the body'. The immune system does not prevent the reinfection but does prevent clinical disease.' HIV vaccine researchers should not automatically assume that a vaccine candidate has failed if it does not prevent reinfection or that superinfection is guaranteed to hamper effectiveness of a vaccine.
Levy does concede, however, that reinfection with a viral strain resistant to anti-HIV medications can diminish the effectiveness of antiretroviral treatment by introducing virus that can thwart the drugs.