Measles Outbreaks and Vaccination Policies in the US

Developing StoryLast updated APR 26
SUMMARY

A South Carolina senator proposed a bill on April 21, 2026, to eliminate religious exemptions for measles vaccinations in schools and childcare facilities, as the state's largest measles outbreak since 2000, with 997 cases, neared its potential end. As of April 21, 2026, South Carolina health officials reported no new measles cases in the Upstate outbreak since April 18, with the total remaining at 997, and the outbreak could officially conclude on April 26 if no additional cases are reported. However, a new case was reported on April 17 in an adult Saluda County resident who contracted the illness through international travel, bringing the state's total to 1,001 cases since July 2025. The Upstate outbreak, which began in October 2025, was previously declared over on March 20, 2026, after 42 days without new cases, with 932 of the 997 cases occurring in unvaccinated individuals. Nationally, the CDC reported 1,487 confirmed measles cases as of March 19, 2026.

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April 2026 — 4 developments

  1. A South Carolina senator has proposed a bill to eliminate religious exemptions for measles vaccinations in schools and childcare facilities.

    A South Carolina senator has proposed a bill to eliminate religious exemptions for measles vaccinations in schools and childcare facilities. This legislative action comes as the state's largest measles outbreak since 2000, with 997 cases reported as of April 21, 2026, is nearing its potential end on April 26, 2026, following two weeks without new infections.

  2. South Carolina health officials reported no new measles cases since April 18, 2026, with the Upstate outbreak total remaining at 997.

    South Carolina health officials reported no new measles cases since April 18, 2026, with the Upstate outbreak total remaining at 997. If no additional cases are reported, the outbreak could officially conclude on April 26, 2026.

  3. The South Carolina Department of Public Health reported a new measles case on April 17, 2026, in an …

    The South Carolina Department of Public Health reported a new measles case on April 17, 2026, in an adult Saluda County resident who contracted the illness through international travel. This case is separate from the Upstate outbreak, bringing the state's total to 1,001 cases since July 2025.

  4. Utah has emerged as the national hotspot for measles cases, while South Carolina's outbreak, with 99…

    Utah has emerged as the national hotspot for measles cases, while South Carolina's outbreak, with 997 cases and no new reports since March 17, is anticipated to officially end on April 26, 2026, if no further cases emerge.

March 2026 — 13 developments

  1. South Carolina reported no new measles cases between March 21 and March 24, 2026, marking the first full week without new infections in months.

    South Carolina reported no new measles cases between March 21 and March 24, 2026, marking the first full week without new infections in months. Two individuals remain in quarantine until March 28, and the outbreak could be declared over by April 26 if no further cases emerge.

  2. The measles outbreak in South Carolina's Upstate region, which began in October 2025, has been declared over as of March 20, 2026, after 42 days without new cases.

    The measles outbreak in South Carolina's Upstate region, which began in October 2025, has been declared over as of March 20, 2026, after 42 days without new cases. The outbreak resulted in 997 reported cases, with the majority (932) occurring in unvaccinated individuals, and significantly impacted children and teens. Nationally, the CDC reported 1,487 confirmed measles cases as of March 19, 2026.

  3. The measles outbreak in South Carolina is nearing containment with only one new case reported recently, bringing the total to 997.

    The measles outbreak in South Carolina is nearing containment with only one new case reported recently, bringing the total to 997. Vaccination rates have significantly increased, with Spartanburg County seeing a 162% surge in MMR vaccinations in January 2026. Nationally, the US has reported 1,362 measles cases since January 1, 2026.

  4. As of March 13, 2026, South Carolina has reported 996 measles cases, with 934 cases concentrated in Spartanburg County.

    As of March 13, 2026, South Carolina has reported 996 measles cases, with 934 cases concentrated in Spartanburg County. Three new cases were identified on this date, bringing the total to 996. Currently, 30 people are in quarantine and four are in isolation, with 930 of the infected individuals being unvaccinated.

  5. State Epidemiologist Dr.

    State Epidemiologist Dr. Linda Bell stated on March 12, 2026, that the slowing spread of measles should not lead to complacency, particularly with spring break approaching. While case numbers have slowed, health officials remain concerned about a potential surge due to increased travel during school breaks. The CDC continues to deploy "disease detectives" to aid in containment strategies.

  6. The South Carolina Department of Public Health reported two new measles cases since Friday, increasing the total to 993 as of March 10, 2026.

    The South Carolina Department of Public Health reported two new measles cases since Friday, increasing the total to 993 as of March 10, 2026. Currently, 42 people are in quarantine and two are in isolation, with the latest quarantine period expected to end on April 2.

  7. The South Carolina Department of Public Health reported one new measles case, bringing the outbreak total to 991 as of March 6, 2026.

    The South Carolina Department of Public Health reported one new measles case, bringing the outbreak total to 991 as of March 6, 2026. Of these cases, 925 are unvaccinated, 26 are fully vaccinated, 19 are partially vaccinated, and the vaccination status of 21 is unknown. Nationwide, 1,277 confirmed measles cases have been reported in 2026, with 1,281 total cases reported by 31 jurisdictions as of March 5, 2026.

  8. The South Carolina Department of Public Health reported one new measles case, bringing the total to 991.

    The South Carolina Department of Public Health reported one new measles case, bringing the total to 991. The Centers for Disease Control and Prevention is deploying three officers to assist with data analysis, expected the week of March 9. February saw a significant increase in vaccinations, with over 17,300 doses administered statewide, a 70% rise compared to February 2025.

  9. The U.S. Centers for Disease Control and Prevention is deploying staff to South Carolina to assist i…

    The U.S. Centers for Disease Control and Prevention is deploying staff to South Carolina to assist in containing the state's measles outbreak, which has reached 990 cases as of March 3. Concurrently, the South Carolina Senate has advanced a bill that would prohibit vaccine mandates for children under two years old, despite existing optional vaccine policies. Health officials noted a 70% increase in vaccinations in February, potentially contributing to a slowdown in infections.

  10. South Carolina has spent an estimated $1.

    South Carolina has spent an estimated $1.6 million on public health efforts to combat its measles outbreak, which has reached 990 cases. The majority of the cost is attributed to personnel dedicated to investigating cases and tracing contacts. Funding for these efforts is sourced from the CDC and other state and federal entities.

  11. South Carolina health officials reported five new measles cases as of March 3, 2026, bringing the total to 990.

    South Carolina health officials reported five new measles cases as of March 3, 2026, bringing the total to 990. A new public exposure site was identified at Westgate Baptist Church in Spartanburg on February 22. Officials continue to emphasize vaccination as the most effective prevention method.

  12. Public health officials in Placer County, California, reported three confirmed measles cases believed to be linked to the South Carolina outbreak.

    Public health officials in Placer County, California, reported three confirmed measles cases believed to be linked to the South Carolina outbreak. These cases are connected to one family, with officials suspecting a fourth member may also be infected. The Placer County cases are thought to have resulted from exposure to an extended family member who recently traveled to South Carolina.

  13. As South Carolina grapples with a measles outbreak, groups associated with Robert F.

    As South Carolina grapples with a measles outbreak, groups associated with Robert F. Kennedy Jr. are actively campaigning to eliminate immunization requirements for children. Health advocates warn that weakening vaccine mandates could lead to lower vaccination rates and increased illness. The CDC notes that measles is still prevalent globally and vaccination remains crucial.

February 2026 — 9 developments

  1. The South Carolina Department of Public Health reported six new measles cases since Tuesday, bringing the total to 985.

    The South Carolina Department of Public Health reported six new measles cases since Tuesday, bringing the total to 985. Public exposures have been identified at Sugar Ridge Elementary and a Costco on Blackstock Rd. in Spartanburg. Nationwide, 1,136 confirmed measles cases have been reported to the CDC since January 1.

  2. South Carolina's State Epidemiologist Dr.

    South Carolina's State Epidemiologist Dr. Linda Bell stated that the measles outbreak, totaling 979 cases as of February 25, 2026, remains a "great concern" despite a downward trend in new infections. She cautioned that pockets of unvaccinated individuals and upcoming spring breaks pose risks for continued transmission, though the outbreak may end sooner than projected. The outbreak is centered in Spartanburg County and has resulted in 21 hospitalizations.

  3. South Carolina's measles outbreak is showing signs of slowing down, with case counts similar to early December levels and only six new infections reported on February 24, 2026.

    South Carolina's measles outbreak is showing signs of slowing down, with case counts similar to early December levels and only six new infections reported on February 24, 2026. State health officials express cautious optimism that the outbreak may end sooner than projected. The total number of cases has reached 979, with the majority concentrated in Spartanburg County.

  4. South Carolina's Department of Public Health reported 979 measles cases as of February 24, 2026, with a slowdown in new infections.

    South Carolina's Department of Public Health reported 979 measles cases as of February 24, 2026, with a slowdown in new infections. The majority of cases (913) are among unvaccinated individuals, and 21 hospitalizations have been recorded since the outbreak began in October 2025. Currently, 91 people are in quarantine and one is in isolation.

  5. Medical experts suggest that measles-related hospitalizations in South Carolina are significantly un…

    Medical experts suggest that measles-related hospitalizations in South Carolina are significantly underreported because the state does not mandate hospitals to report these admissions. While official figures show 20 measles-related hospital admissions, experts believe this number is a substantial underestimate, contributing to the nation's largest measles outbreak since 2000.

  6. South Carolina reported 11 new measles cases between February 18 and February 20, 2026, bringing the total outbreak count to 973.

    South Carolina reported 11 new measles cases between February 18 and February 20, 2026, bringing the total outbreak count to 973. New public exposure sites have been identified in Spartanburg County, including Mabry Middle School, Spartanburg Community College's Giles Campus, and Costco. Nationally, the CDC confirmed 66 new measles infections, raising the US total for 2026 to 982.

  7. The South Carolina Department of Public Health reported 11 new measles cases, bringing the total outbreak count to 973.

    The South Carolina Department of Public Health reported 11 new measles cases, bringing the total outbreak count to 973. New public exposure sites have been identified, including Mabry Middle School, two churches, a Costco, and a community college in Spartanburg. Currently, 105 people are in quarantine and seven are in isolation, with quarantine end dates extending to March 15.

  8. South Carolina's measles outbreak has now reached 973 cases, with reports indicating a potential slowing of the spread.

    South Carolina's measles outbreak has now reached 973 cases, with reports indicating a potential slowing of the spread. The latest figures show an increase from previous counts, with some sources reporting up to 962 cases and others 973.

  9. The South Carolina measles outbreak has reached 789 cases in the Upstate, with 89 new cases reported…

    The South Carolina measles outbreak has reached 789 cases in the Upstate, with 89 new cases reported since Friday, and has led to exposures in critical locations including hospital maternity units, and major employers like BMW and Michelin plants.

January 2026 — 10 developments

  1. The South Carolina Department of Public Health announced on January 30 that the state's measles outb…

    The South Carolina Department of Public Health announced on January 30 that the state's measles outbreak has reached 847 cases, with public exposure sites suggesting widespread community transmission.

  2. Two measles cases were confirmed in Mecklenburg County, North Carolina, with one adult contracting t…

    Two measles cases were confirmed in Mecklenburg County, North Carolina, with one adult contracting the illness through travel and an unvaccinated child through contact with an infected individual from Spartanburg, South Carolina. The South Carolina Department of Public Health also reported that some measles cases have no identified source, indicating community circulation of the virus.

  3. As of January 22, 2026, the United States has reported 416 confirmed measles cases, with 413 originating from 14 jurisdictions, including South Carolina.

    As of January 22, 2026, the United States has reported 416 confirmed measles cases, with 413 originating from 14 jurisdictions, including South Carolina. The majority of these cases, 393, are associated with outbreaks that began in 2025.

  4. At least 15 elementary, middle, and high schools have been impacted by the measles outbreak in South Carolina.

    At least 15 elementary, middle, and high schools have been impacted by the measles outbreak in South Carolina.

  5. The measles outbreak in South Carolina has reached 664 cases, and officials have confirmed the virus has also spread to Ohio and Washington state.

    The measles outbreak in South Carolina has reached 664 cases, and officials have confirmed the virus has also spread to Ohio and Washington state.

  6. As of January 20, 538 people were in quarantine and 33 in isolation due to the outbreak.

    As of January 20, 538 people were in quarantine and 33 in isolation due to the outbreak. The ongoing spread has raised concerns that the United States may lose its measles elimination status.

  7. The measles outbreak in South Carolina has surged to 646 cases and spread to Clemson University, with a confirmed case reported there.

    The measles outbreak in South Carolina has surged to 646 cases and spread to Clemson University, with a confirmed case reported there. This rise in cases has led to concerns that the United States could lose its measles elimination status, and neighboring North Carolina has also reported linked cases.

  8. Measles cases in South Carolina soared past 400, with the outbreak being described as the largest in…

    Measles cases in South Carolina soared past 400, with the outbreak being described as the largest in the country and the second largest recorded in the past year in the United States.

  9. The measles outbreak in South Carolina is intensifying with almost 100 new cases.

    The measles outbreak in South Carolina is intensifying with almost 100 new cases. Hospitals in the Lowcountry are implementing safety precautions like masking and visitor restrictions as flu cases rise.

  10. Officials announced the measles outbreak had grown to 185 cases, with 172 of those involving unvaccinated patients.

    Officials announced the measles outbreak had grown to 185 cases, with 172 of those involving unvaccinated patients.

December 2025 — 3 developments

  1. South Carolina's statewide measles cases rose to 156, with 153 attributed to the Upstate outbreak.

    South Carolina's statewide measles cases rose to 156, with 153 attributed to the Upstate outbreak. State epidemiologists noted this as the highest measles activity in over 30 years.

  2. The total number of infected individuals since October reached 126, with more than 300 people in quarantine and 13 in isolation, predominantly in Spartanburg County.

    The total number of infected individuals since October reached 126, with more than 300 people in quarantine and 13 in isolation, predominantly in Spartanburg County.

  3. South Carolina health officials reported an 'accelerating' measles outbreak, totaling 111 cases, with hundreds of people placed in quarantine.

    South Carolina health officials reported an 'accelerating' measles outbreak, totaling 111 cases, with hundreds of people placed in quarantine. The outbreak was primarily centered on a single church and several schools in Spartanburg County.

October 2025 — 2 developments

  1. The South Carolina Department of Public Health issued a health alert confirming the measles outbreak…

    The South Carolina Department of Public Health issued a health alert confirming the measles outbreak in the Upstate region, defining an outbreak as three or more epidemiologically linked cases.

  2. The South Carolina Department of Public Health (DPH) confirmed an outbreak of measles in the Upstate…

    The South Carolina Department of Public Health (DPH) confirmed an outbreak of measles in the Upstate region, with a total of eight cases reported, five of which were part of a newly identified outbreak.