A global immunization program has eliminated smallpox ​ — the lethal disease that claimed more lives than all the wars of the 20th century combined — ​ and a similar campaign has almost eradicated polio.
Program imunisasi global telah melenyapkan cacar ​ — penyakit mematikan yang merenggut lebih banyak jiwa daripada semua perang pada abad ke - 20 ​ — dan kampanye serupa hampir sepenuhnya memberantas polio.