Florida ties 76 hepatitis A cases to travel to Cuba, with strains matching across regions

Florida public health staff noticed something unusual early in 2025: an outsized share of the state's reported hepatitis A cases were turning up in people who had recently returned from Cuba. A report in the US Centers for Disease Control and Prevention's Morbidity and Mortality Weekly Report, published on 24 September, documents what that signal became.

During June 1, 2024–February 28, 2026, among 249 hepatitis A cases reported in Florida, 76 (31%) were associated with recent travel to Cuba [s1]. A total of 79 cases (32%) met the outbreak case definition [s1], and 46 (58%) of those 79 patients lived in Miami-Dade County [s1]. Outbreak-associated cases occurred among residents of 13 counties in Florida [s1] — a spread consistent with a virus being imported repeatedly rather than circulating from a single local source.

A travel-acquired outbreak, not a foodborne one

The patient profile fits a travel exposure rather than a contaminated-product recall. Among outbreak-associated patients the median age was 39 years, 70% were male, 87% were White, and 92% were Hispanic or Latino [s1]. The median length of stay in Cuba was 11 days, with an interquartile range of 6–26 days [s1].

The illness was not mild. Seventy-two percent were hospitalised and no deaths occurred [s1]. That hospitalisation rate is high for hepatitis A, and reflects both the age of the patients — the disease tends to be more severe in adults than in the young children who dominate transmission in endemic settings — and the fact that mild cases in returning travellers are the least likely to be captured in surveillance at all.

The genotyping is what makes it an outbreak

Case counts alone cannot prove a common source. Sequencing can. Of the isolates genotyped, 15 (83%) matched hepatitis A virus genotype IA outbreak strain 1, two (11%) matched IB strain 1, and one (6%) matched IA strain 2 [s1]. A dominant shared strain across geographically separated patients is the molecular signature of a single epidemiologic event — here, exposure in Cuba — rather than a coincidence of unrelated infections.

It has not stopped

The report's window closes at the end of February 2026, but the outbreak does not. Additional cases in Florida residents have been identified since March 2026, with exposures in Cuba as recently as August 2026 [s1]. That is the sentence that moves this from a retrospective write-up to a live travel-health advisory.

What travellers are being told

Hepatitis A is transmitted primarily by the faecal-oral route — when an uninfected person ingests food or water contaminated with the faeces of an infected person [s2]. Its incubation period is usually 14–28 days [s2], long enough that a traveller can return home, feel well for weeks, and only then fall ill, by which point the Cuba link is easy to miss without a careful travel history.

The CDC's practical guidance is pre-travel vaccination. Providers are advised to review hepatitis A vaccination recommendations and to consider immune globulin for high-risk travellers — adults older than 40 years, immunocompromised persons, and people with chronic liver disease — who are departing within two weeks [s1]. The two-week caveat matters: the vaccine needs time to generate protection, so a last-minute traveller in a high-risk group is the one for whom immune globulin is specifically mentioned.

The wider frame

Hepatitis A is not a high-mortality disease by global standards — WHO attributes 35,569 deaths worldwide in 2023 to it, 2.6% of all deaths from viral hepatitis [s2]. What this outbreak illustrates is less about lethality than about surveillance: a destination with changing transmission conditions can seed cases across a dozen US counties before the pattern is named, and the naming depends on clinicians asking where a jaundiced adult has recently been.

What to watch

The open questions are the duration of elevated risk in Cuba and whether other states see the same imported strains. Florida caught this because its case numbers were large enough for a proportion to stand out; a smaller state with the same per-traveller risk might log only a handful of cases and never connect them. The genotyping link is the thread to follow — if IA outbreak strain 1 surfaces in travellers returning to other jurisdictions, the exposure is still open.

Sources

• Hepatitis A Outbreak Associated with Cuba — Florida, June 2024–February 2026 — MMWR (CDC), 24 September 2026
• Hepatitis A (fact sheet) — World Health Organization