The South Carolina measles outbreak stands at 997 cases after just one new case was reported in recent days, suggesting the outbreak may be nearing containment. 

The outbreak began in the Upstate region last October, and was linked to several private schools with low vaccination rates among the student body. Cases mounted and then soared over the holidays, with multiple exposures at churches noted.

Officials said there are currently eight people in quarantine and none in isolation, the lowest numbers recorded since the outbreak began. The latest end of quarantine for these is April 2.

Of the 997 cases, 639 are among children ages 5 to 17 years, and 263 and in those are under the age of 5 years. Only 87 infections have been in adults, and eight are unknown. The vast majority case-patients (932 [94%]) are unvaccinated, and 20 are partially vaccinated with one dose of measles-containing vaccine. Twenty are fully vaccinated, and 19 have unknown vaccination status. 

So far the United States has tracked 1,362 measles cases since January 1, putting the nation on track for a record-setting year. 

Colorado, North Dakota report new cases 

Measles cases are being reported in 30 states across the country. In Colorado, one new case raises the state total this year to 11, nine of which were confirmed this month.

North Dakota is reporting 26 cases so far this year, including four requiring hospitalization. Three of the cases are new. Until last year, the state had not seen any measles activity since 2011. Eighteen of the 26 confirmed case-patients were unvaccinated, but six were fully vaccinated. 

Twenty-three cases have been confirmed in Pembina County, with one case each in Williams, Walsh and Traill counties.

A research letter published yesterday in JAMA Pediatrics suggests that while most teens seen in Children’s Hospital of Philadelphia (CHOP) primary care clinics completed the human papillomavirus (HPV) vaccine series before becoming sexually active, 12% had not received any doses, representing a missed opportunity for cancer prevention. 

The researchers analyzed the electronic health records (EHR) from 9,491 patients aged 13 to 18 years seen at 31 CHOP-affiliated primary care practices from September 2023 to September 2025. The teens had reported sexual activity on the Adolescent Health Questionnaire.

The average patient age was 17.0 years, 47% were girls, 40% were Black, 40% were White, 9% were Hispanic, 11% were another race, 44% were Medicaid-insured, and 33% lived in very low Child Opportunity Index neighborhoods.

Starting series at age 9 reduced unvaccination rates

In total, 79% of teens had completed the HPV vaccine series before becoming sexually active, 12% hadn’t received any dose, and 9% had started but not completed the series. Of patients who were unvaccinated before starting sexual activity, 70% were never vaccinated, 23% later initiated the series, and 7% completed the series after becoming sexually active. Unvaccinated teens were disproportionately White (49%) and commercially insured (59%).

Given that all adolescents had recent primary care visits, family acceptance of vaccination, physician recommendation practices, and clinic workflows, rather than health care access, likely drive missed opportunities.

Clinic-level pre-sex vaccination rates ranged from 5% to 47%. Greater neighborhood opportunity, commercial insurance, and longer distance from the main hospital were linked to an increased likelihood of not being vaccinated before initiation of sexual activity. Clinics that more often initiated HPV vaccination at age nine had lower unvaccination rates (−0.89%).

“Given that all adolescents had recent primary care visits, family acceptance of vaccination, physician recommendation practices, and clinic workflows, rather than health care access, likely drive missed opportunities,” the study authors wrote.

The finding of higher vaccine uptake in clinics that more often started HPV vaccination earlier in life supports offering HPV vaccination at age nine or 10. “Additional strategies to routinize HPV vaccination and reduce variation should include presumptive communication, staff training, and workflow redesign,” they wrote. 

Shingles vaccination may halve the one-year risk of serious cardiac events among older adults who have heart disease, adding to accumulating evidence that the vaccine may protect against health conditions in addition to shingles (herpes zoster), University of California researchers say.

The study findings will be presented at the upcoming American College of Cardiology’s Annual Scientific Session in New Orleans. 

Previous studies have suggested that shingles can lead to the formation of blood clots around the brain and heart, posing a risk of heart attacks, strokes, and venous blood clots. Preventing shingles infection through vaccination is believed to prevent these clots.

Risk reduction on par with quitting smoking

The investigators analyzed electronic health record data from 246,822 US adults aged 50 years and older diagnosed as having atherosclerotic heart disease (plaque buildup in the arteries) from 2018 to 2025. Participants were 123,411 people who had received at least one dose of either the Shingrix or Zostavax shingles vaccine and the same number of unvaccinated controls.