Figure: 4 TAC §35.2(b)(2)(A)

Test Interpretation Non-Strain 19 Vaccinated Strain 19 Vaccinated
Negative 1 + 1:10 or lower 1 + 1:10 or lower
Suspect 2 + 1:10 through 2 + 1:20 2 + 1:10 through 4 + 1:20
Reactor 2 + 1:20 or higher 1 + 1:40 or higher

Degree of fixation of complement: 1 + = 25%; 2 + = 50%; 3 + = 75%; 4 + = 100%