Vaccine-induced cellular immune responses do not affect the number of low-dose intrarectal challenges required for infection with SIVmac239a

Vaccinated or control animalNo. of challenges
    Geometric mean4.50
    Geometric mean4.17
  • a Animals were challenged intrarectally with 300 TCID50 of SIVmac239. One week later, plasma was analyzed for viral concentration, and the animal was rechallenged while awaiting the results of the viral concentration determination. The date of infection was considered to be 7 days prior to the first positive viral concentration, and the number of challenges was considered to be how many had occurred, including the one on this date.