The ongoing measles outbreak in South Carolina is now considered the largest measles outbreak in over 30 years in the state and one of the largest outbreaks in the U.S. in recent years. While case numbers are declining, some public health officials warn that the situation remains fragile.
For nurses and other healthcare professionals across South Carolina and in other regions, this outbreak highlights the critical importance of early recognition, infection control, vaccination outreach, and coordinated public health response. Here is what you need to know about the current situation.
A look at the SC measles outbreak timeline
The SC measles outbreak began with a confirmed case in July 2025, which was the first confirmed case since September 2024. Initial case counts rose gradually over the next few months, with the South Carolina Department of Public Health (DPH) confirming a measles outbreak by October.
In December, transmission accelerated sharply, as cases grew to over 200, marking the peak of the outbreak. By February, the rate of new infections began to decline, and as of the 22nd week of the outbreak, the number of new cases hovered around 10 per week, according to South Carolina Public Radio.
Although the decline in confirmed cases is a hopeful sign, Linda Bell, MD, state epidemiologist and Health Programs Branch Director for the South Carolina DPH, has emphasized the need for continued vigilance.
"This is not over yet, it's not nearly over yet," she said in a South Carolina Public Radio article, adding that groups of under-vaccinated individuals remain at risk.
"That ongoing susceptibility in our population may continue to fuel ongoing spread," Bell said.
Current case counts and impact
Since the outbreak began in 2025, South Carolina DPH has confirmed, as of March 17, 2026:
- 997 total measles cases
- 940 cases in Spartanburg County, the outbreak’s epicenter
- 456 cases in children aged five to 11 and 256 cases in children under age four
| Vaccination Status | Number of Cases |
| Unvaccinated | 931 |
| Fully vaccinated | 25 |
| Partially vaccinated | 21 |
| Unknown vaccination status | 20 |
The concentration of cases in Spartanburg County underscores how rapidly measles can spread within communities where immunity gaps exist.
Why the outbreak is slowing
One of the most notable shifts during the SC measles outbreak has been the surge in measles, mumps, and rubella (MMR) vaccination rates.
In January alone, there was a statewide increase (72%) in MMR vaccinations compared to January of the previous year. In Spartanburg County, there was a 162% increase in MMR vaccinations.
This decline in new measles cases can be attributed to these increased vaccination rates, said Bell in an article by The State. This aligns with established data showing that two doses of the MMR vaccine are approximately 97% effective at preventing measles, according to the Infectious Diseases Society of America.
Other measles outbreaks across the U.S.
South Carolina isn't alone in experiencing a measles outbreak. According to the Centers for Disease Control and Prevention (CDC), multiple outbreaks have occurred across the United States in 2025 and early 2026, including in Texas, Utah, Arizona, and Florida.
| Year | 2026 (to date) | 2025 |
| Total Cases in the U.S. | 1,362 | 2,284 |
This recent data shows that measles continues to spread quickly in many communities, with many cases affecting children. Even a single travel-related case can lead to multiple infections when community immunity is low, according to the CDC.
For nurses, this reinforces an important takeaway. Measles should remain on your radar, even outside of known local outbreaks. Ongoing cases nationwide highlight the need for continued vaccination efforts and clinical vigilance.
Clinical recognition remains critical
Despite the decline, measles remains highly contagious. You should maintain a high index of suspicion, especially during peak travel season.
Key clinical features of measles include:
- High fever (often exceeding 100°F)
- Cough
- Runny nose
- Conjunctivitis
- Koplik spots, white in color, inside the mouth
- Rash beginning on the face and spreading downward
Patients are contagious from four days before the rash occurs to four days after, making early identification and isolation essential. Because measles can remain airborne for up to two hours after an infected person leaves an area, airborne precautions are necessary, especially in healthcare settings when measles is suspected.
Infection control in healthcare settings
When it comes to infection prevention, quick, consistent action makes a significant difference in protecting both patients and staff. According to the Occupational Safety and Health Administration and the National Library of Medicine, when an airborne illness is suspected, the following steps should be taken right away:
- Give the patient a mask and move the patient to an airborne infection isolation room (AIIR) as soon as possible, if one is available, to safely contain airborne pathogens.
- Protect yourself and wear a fit-tested N95 respirator (or higher-level protection) before entering the room or area to ensure proper respiratory protection.
- Limit exposure to immune staff members when feasible, especially during an active outbreak, to reduce the risk of transmission within the healthcare team.
Just as important is maintaining accurate records of staff vaccination status and confirmed immunity. During an outbreak, having up-to-date and easily accessible immunity documentation allows facilities to make informed staffing decisions quickly and helps ensure compliance with public health guidelines.
Quarantine and isolation
Isolation applies to confirmed cases during the contagious period. Quarantine applies to individuals exposed to measles who lack documented immunity and are within the incubation window.
Nurses and healthcare professionals play an important role in educating families about:
- Monitoring for symptoms during the seven- to 21-day incubation period
- When to seek care
- Calling ahead before presenting to a healthcare facility
Final thoughts
The SC measles outbreak demonstrates both how quickly measles can spread and how quickly community-level vaccination efforts can reverse trends. As the state enters a season of increased travel, gatherings, and mobility, vigilance must remain a priority. Measles doesn’t require large exposures to spread. Just one infectious individual in a susceptible population can ignite new transmission chains.
