Lab results said hpv 16&18 were not detected. but says i may still be at high risk for disease..what could this be?

HPV: There are thirteen strains of hpv that can cause cancer and death. Four of the strains cause 95% of this disease, and the U.S. Gardisil vaccine covers those four. There is not good hpv testing yet that can really distinguish between the strains well, especially given that here are over 140 different hpv strains. The test we use with pap smears in washington state give us more of these than yours.