The Centers for Disease Control and Prevention is sending experts to Samoa after a measles outbreak there killed 32 people, mostly children, and sickened 2,437 people, according to U.S. officials. The outbreak was declared on Oct. 16 and is spreading throughout the island, with children under 5 accounting for nearly half of the cases, CDC officials said. Twenty-eight of the 32 deaths were children under the age of 5, and more than 90 percent of those recently admitted to hospitals were children, according to officials. The Washington Post reports that the outbreak is expected to spread, as Samoa has one of the lowest vaccination rates in the world. Samoa’s Health Ministry said 243 cases were reported in the last 24 hours. “It does not appear, from the numbers we’ve been seeing, that it has peaked yet,” Helen Petousis-Harris, a vaccine safety expert at the University of Auckland in New Zealand, told the Post. “This is really severe.” The average mortality rate for measles in a country with Samoa’s income level is about 2 per 100 cases, Petousis-Harris told the Post.