Spinner C, et al. - Researchers evaluated the 9-Valent and 4-Valent HPV vaccine effectiveness in vaccinated young women, and assessed herd protection in unvaccinated young women, before and during the 11 years after HPV vaccines introduction in a community. They found significant decreases in vaccine-type HPV in vaccinated women during the 11 years after HPV vaccine introduction, which displayed vaccine effectiveness. The decreases in 9-valent vaccine-type HPV and the 5 additional HPV types in the 9-valent vaccine could suggest cross-protection against additional types in the 9-valent vaccine that were genetically related to types in the 4-valent vaccine since lesser women in wave 4 had received the 9-valent vaccine. Data revealed that the lack of a significant decrease in vaccine-type HPV could suggest a lack of herd protection or unvaccinated women practice behaviors led to higher risk for acquiring HPV among unvaccinated women.