Can the AIDS Pandemic be Curtailed Through the Use of Current HIV Vaccines and Highly Active Antiviral Therapies?

JUN 10 '97 11:48AM AAAS SCIENCE MAGAZINE JUN3.3, i997 12 ' 5P 3
ROM: Mulit Ins,Lab - U PHONE NO. 66161850
Roml Mullins Lab - UW'
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vaccinated and SIV infected macaques suggest that they may survive longer (12).
Furthermore, kIV-1 transmission from a vaccinee or an individual with slippressed
virus load may be less efficient. Such a reduction in infectiousness would slow the rate
of spread of the epidemic, with the beneficial impact increasing over time (13,14).
These considerations suggest a series of crucial experiments to assess the
viability of a vaccination approach with the reduction of infectivity as a goal. First,
animal vaccine studies have had limited follow-up post-infLectlorv a long term benefit on
survival should be convincingly demonstrated. Second, cohorts of initially IV-I.
infection discordant couples should be expanded to provide the statistical power
necessary to determine if there is indeed an association between plasma and/or genital
virus load and sexual transmission rate. Third, in the continued absence of a critical
mass of data on the above issue, animal model studies that evaluate transmission rates
under natural conditions of exposure could be conducted with virus load and
vaccination as variables. Fourth, whether vaccination of humans with the current
vaccine candidates leads to a diminution in virus load in subsequently infected
individuals needs to be carefully evaluated and confirmed.
For the more than 90% of HIV-1 infected individuals in the world who reside in
developing countries, and who are considered by some to be beyond the financial reach
of the current batch of highly active antiretroviral therapies that can substantially
reduce virus load, a strong argument may be made for going forward with large scale
vaccination programs prior to development of a vaccine with significant likelihood of
preventing infection if the vaccine has the reasonable likelihood of satisfying the above

criteria. As with all HIV vaccine programs under consideration, the potential