Vaccination is still fraught with controversy. Latter-day anti-vaccination activists echo many of the concerns, as well as the tactics, of their nineteenth-century antecedents. Certain spiritual and religious communities object to it as part of an overall rejection of medical treatment in favor of the healing powers of prayer and faith. Such groups include everyone from faith healers in Philadelphia (among whom a 1990-1991 measles outbreak lead to the death of 9 children) to the followers of Maharishi Mahesh Yogi
in Fairfield, Iowa, where a 2006 outbreak required the quarantine of roughly 1,000 people, as described by Arthur Allen in his book Vaccine: The Controversial Story of Medicine’s Greatest Lifesaver.