The United States recorded 2,170 confirmed measles cases in 2026 as of July 2 [2]. The FIFA World Cup — with international visitors moving through stadiums, fan zones, and transit hubs across the United States, Canada, and Mexico — is still running, and measles is already circulating in all three host countries [1].

This paper's July 3 briefing on CDC's guidance explained how the two-week rule converts immunity status into a departure-date task. That task has not expired. Anyone attending remaining matches who lacks full MMR documentation needs a shot at least 14 days before walking into a venue [1].

The gap has not closed. Adults who received only one MMR dose — a common outcome for those vaccinated before 1989, when the two-dose schedule became routine — have partial but not complete protection [1]. Infants under six months cannot receive the vaccine at all [1]. Two doses provide 97 percent protection; one dose provides 93 percent [1]. Against active transmission in a crowd of tens of thousands, that four-point gap is consequential arithmetic.

Check your written vaccination record. If it shows one dose and you were born after 1956, make the appointment.

-- NORA WHITFIELD, Chicago