Measles was declared eliminated in the United States in 2000.^[1] This week a commission of the Pan American Health Organization is meeting in Washington, from Tuesday to Friday, to review whether that is still true.^[2] The United States, Mexico, Guatemala, Peru and Bolivia all risk losing their elimination status.^[3] Read together, the agency figures and four news reports describe a country that has already met the test for losing it. What remains is the announcement. The rule A country loses its measles elimination status if one strain of the virus spreads without interruption for 12 months.^[4] The onset of the United States outbreak was 20 January 2025.^[5] Mexico's was 1 February 2025.^[6] By that starting date, the American outbreak passed the 12-month line in January of this year. It is now in its 22nd month. The organization said in March that it would review the status of the United States and Mexico in November.^[7] The review takes place during the commission's regular annual meeting.^[8] The commission is an independent technical body that reports to the organization's director.^[9] The numbers As of 5 November, 5,182 confirmed measles cases had been reported in the United States in 2026.^[10] There were 2,289 in the whole of 2025.^[11] There were 285 in 2024.^[12] Set in a row, those three figures show cases multiplying eightfold from 2024 to 2025 and then more than doubling again with eight weeks of this year still to run. The pace has been steady. There were 4,410 confirmed cases as of 15 October.^[13] The count rose by 772 in the three weeks after that. The Centers for Disease Control and Prevention has recorded 43 outbreaks this year.^[14] The outbreak that began in Texas in early 2025 has spread to 45 states.^[15][16] The deaths, and two ways of counting them The death toll is not one number. The CDC confirmed a third measles-related death in the United States this year on 20 October.^[17] Pennsylvania's health authorities alone reported at least five.^[18] The gap comes from method. The CDC now uses mortality data from the National Center for Health Statistics, in place of figures from state health departments, to track measles deaths.^[19] The center verified that measles caused the third death.^[20] The CDC has not disclosed the states where the three deaths occurred.^[21] It said its count may change as reviews are completed.^[22] The lag was visible in September. Pennsylvania reported its third measles-related death of the year then.^[23] She was a 40-year-old woman from Jefferson County.^[24] The two earlier deaths in the state involved infants.^[25] At that point the CDC had no 2026 measles deaths on file.^[26] Pennsylvania One state shows the speed. Pennsylvania had recorded 676 cases in 37 counties when the third death was reported in September.^[27] It had 1,286 confirmed cases as of 19 October.^[28] The count nearly doubled in about five weeks. The CDC said it would deploy additional support to the state.^[29] The vaccine Two doses of the MMR vaccine are 97% effective at preventing measles.^[30] Kindergarten coverage in the United States fell from 95.2% in the 2019-2020 school year to 92.4% in 2025-2026.^[31] That is a fall of 2.8 points in six years, to a level below the 95% mark that coverage held before the decline. The warning The loss of status has been forecast in print. An analysis published in The Lancet concluded that the United States is highly likely to lose its measles elimination status in November 2026.^[32][33] The region The United States is one part of a wider reversal. The Americas eliminated endemic measles transmission in 2016.^[34] Canada lost its elimination status in November 2025, when endemic transmission was re-established there.^[35][36] With it, the Americas as a region lost their measles-free status.^[37] Through the first 43 weeks of 2026 the region reported 57,666 confirmed cases.^[38] That is 4.7 times the figure for the same period of 2025.^[39] Eighty-one deaths were reported.^[40] Seventeen countries and territories had confirmed cases.^[41] The most recent weeks were better. New confirmed cases in the two weeks to mid-October fell 38% from the two weeks before.^[42] What comes next The organization's director, Jarbas Barbosa, makes the final decisions on status.^[43] Announcements are expected early in the week after the conference.^[44] Losing the status changes no law and closes no border. It is a formal finding that a disease the country ended in 2000 circulates in it again. The organization's recommendations for getting the status back are high vaccination coverage, surveillance and a timely response to outbreaks.^[45]