FIG 5.

Serum-neutralizing antibody titers in mice following one or two doses of each of the H2 ca vaccines. Mice were intranasally inoculated with 1 or 2 doses of 10⁶ TCID₅₀ of AA ca, Jap/57 ca, mal/78 ca, or sw/06 ca vaccine and bled 1 month following the last vaccine administration. The vaccine administered and the test antigens are listed on the x axis. The neutralizing antibody titer is listed on the y axis. The symbols represent the titers in individual animals, and the bars indicate the geometric mean. The dotted line indicates the lower limit of detection. nd, not done. Antibody was not detectable (<10) on day 0 prior to vaccination. AA, A/Ann Arbor/6/60; Jap 57, A/Japan/305/1957; Mal 78, A/mallard/NY/6750/1978; Sw 06, A/Swine/MO/4296424/2006.