Table 1.

Demographic parameters, CD4+ T-lymphocyte counts, and stage of HIV infection of study participants

GroupNo. of subjectsMedian (range) age (yrs)No. of males/no. of femalesMedian (range) CD4+countsa (no. of cells/liter [106])No. of subjects with the following CDC stageb:History of tetanus vaccinationc
ABC
HIV infected with CD4+ T-lymphocyte counts of:
 <200 × 106/liter (group I)1337 (22–60)12/140 (10–135)d 00137.6 (1–29)
 ≥200 × 106/liter (group II)1140 (22–59)10/1510 (205–805)7137.7 (1–25)
Controls536 (34–43)3/2Not done8 (1–23)
  • a Normal range of absolute CD4+ counts, 560 × 106 to 1,550 × 106/liter.

  • b CDC stage, Centers for Disease Control and Prevention stage of HIV infection (3).

  • c Mean (range) number of years since last tetanus toxoid vaccination.

  • d Nine individuals in group I had CD4+ counts of ≤40 × 106/liter; the remaining four individuals in this group had CD4+ counts in the range of 100 × 106 to 135 × 106/liter.