KANSAS CITY, Mo. (AP) — The University of Kansas Cancer Center is joining nearly 70 other cancer centers in sounding an alarm about the high number of children not getting the HPV vaccine.

The Kansas City Star reports Kansas is last in the nation in the percentage of girls who have received the vaccine, which protects against a virus that causes cancer. The Centers for Disease Control says Missouri isn’t far behind, and both states also rank low in the number of boys who are vaccinated.

Doctor Terry Tsue at the Kansas Cancer Center says he’s troubled that so many children are not getting the vaccine.

He says some people some don’t think their children need the vaccine because they don’t have sex, while others think it will make their kids promiscuous.