The disease is preventable with the polio vaccine; however, multiple doses are required for it to be effective. The US Centers for Disease Control and Prevention recommends polio vaccination boosters for travelers and those who live in countries where the disease is endemic. Once infected there is no specific treatment. In 2018, there were 33 cases of wild polio and 104 cases of vaccine-derived polio. This is down from 350,000 wild cases in 1988. In 2018, the wild disease was spread between people only in Afghanistan and Pakistan. In 2019, there were 175 cases of wild polio and 364 cases of vaccine-derived polio.