Welcome to the ninth edition of FOI Clinical. Each week, we'll send you a briefing on outbreak news. When something urgent breaks, you'll get an alert the same day.
In this edition
Measles - Sexually transmitted Shigellosis - Typhus in California - Plague in New Mexico - Mpox in Germany
National interest
Measles
As of April 2, 2026, there have been 1,671 confirmed cases, up 96 from the week before. The largest case totals continue to be in South Carolina, Utah, Florida, and Texas, though Utah is currently a focal point for new transmission.
The rate of new cases has dwindled, with the South Carolina outbreak effectively over, and the outbreak in Florida slowed. However, this is not the end of the measles resurgence. New clusters will likely emerge in the weeks and months ahead.
- South Carolina: No new cases have been reported since the week of March 8. If no new cases are reported, the outbreak is approximately two weeks away from being declared over.
- Utah: Case counts are climbing rapidly in Utah. There have been 378 cases reported this year, bringing the outbreak total to 575. Another 60 cases were reported last week, double the number reported the week before. While the largest case totals continue to be in Southwest Utah (242), cases have been reporting in areas covered by 11 local health departments, including Utah County (87), Salt Lake County (60), TriCounty (56), and Central Utah (46). There have been more than two dozen exposure locations reported in the past few weeks, including at more than one Walmart location, multiple University of Utah buildings, and numerous clinics and hospitals.
- Texas: As of April 1, there have been 175 confirmed cases. All five of the new cases are associated with federal detention facilities in Hudspeth County (135 total cases have been reported so far in federal detention facilities in the county).
- Florida: New cases appear to be slowing in Florida; as of March 28, there were 144 confirmed cases, an increase of 1 from the week before. The vast majority of cases have been in Collier County (106); while 12 other counties have reported cases, the totals remain in the single digits.
- Arizona: The outbreak along the border with Utah continues, rising to 77 for 2026, and 291 for the total outbreak. 11 new cases were reported in the last week in March.
- North Dakota: As of April 1, 27 cases and 5 hospitalizations have been confirmed in the state this year. After several weeks with no reported cases, 5 were reported between March 23 and April 1, all in Ransom County. However, most cases so far this year in the state (23) have been associated with an outbreak in Pembina County. There have also been single cases reported in Williams, Traill, and Walsh Counties.
- Oregon: 13 cases have been reported in the state this year, 6 since the start of March. The state did not report any cases in 2024 or 2025. Most of the reported cases appear to have been locally acquired, but have not been epidemiologically linked to each other, which suggests there is ongoing community spread that is not being detected.
Sexually transmitted shigellosis
Shigellosis is increasingly being reported as spreading through sexual networks, particularly among men who have sex with men (MSM). The UK Health Security Agency recently reported that in 2025, there were 2,560 cases of sexually transmitted shigellosis, a higher rate than in either of the prior two years.
Case reports are not currently elevated in the United States, according to data from the National Notifiable Disease Surveillance System.
Infection with one of four species of Shigella bacteria produces shigellosis. It is spread via the fecal-oral route, and can be acquired through contaminated food, water, or surfaces or through direct contact. Importantly, particularly for sexual transmission, bacterial shedding in stool can continue for roughly two weeks after symptoms resolve.