Welcome to the twenty-seventh 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
Moderna mFLUSIVA approved – Cyclosporiasis – Salmonella: jalapeños – Measles – West Nile virus – Vibrio vulnificus: Louisiana – Legionnaires': Ohio nursing home – Ebola
National interest
Moderna mFLUSIVA: first mRNA flu vaccine approved
The FDA approved Moderna's mFLUSIVA (mRNA-1010), the world's first licensed mRNA-based seasonal influenza vaccine. Approval is split by age:
- Ages 50–64: Traditional full approval, based on clinical efficacy data from the FLUENT Phase 3 trial (~40,000 participants).
- Ages 65+: Accelerated approval with a required post-licensure confirmatory trial spanning two flu seasons (FDA concern: the trial used standard-dose comparator, not high-dose/adjuvanted vaccines recommended for that age group).
Phase 3 efficacy: The trial found a 27% relative reduction in confirmed influenza illness versus standard-dose flu vaccine; 48% reduction in healthcare utilization (ED visits, hospitalizations). Reactogenicity was consistent with other mRNA vaccines, with reported symptoms including transient fatigue, myalgia, arthralgia. There were no new safety signals. Moderna expects doses available within weeks, in time for the 2026–2027 flu season.
The mRNA platform compresses vaccine manufacturing from ~6 months to 2–3 months, which addresses the strain-mismatch problem that undermines annual vaccine effectiveness when antigenic drift occurs between strain selection and distribution. The accelerated approval pathway for 65+ means this age group can begin receiving mFLUSIVA immediately, with confirmatory efficacy data required post-market.
Cyclosporiasis: Michigan fading, Ohio still climbing
The outbreak trajectory is diverging by state. Michigan's MDHHS lifted its precautionary salad advisory August 6, calling the outbreak "fading." Michigan is now reporting 12,485 cases and 279 hospitalizations as of August 6. Reported cases in Ohio continue to climb: >4,900 statewide as of August 4, with a second consecutive week of significant increases. Missouri is also heavily affected, with more than 1,000 cases reported.
Nationwide, approximately 24,300 cases have been reported (13,895 confirmed + 10,455 probable or under investigation) across 45+ states. A subset of 6,358 cases in 15 states is formally linked to the Taylor Farms de México/Taco Bell iceberg lettuce cluster. The Taylor Farms recall remains in effect (27 states). No product sample has tested positive; epidemiological and traceback evidence remains the basis for the recall.