A person in San Francisco has been diagnosed with measles in the city's first case of the disease since 2013, the San Francisco Department of Public Health said in a Tuesday health advisory.

The person confirmed to have measles is an adult who was exposed to the virus during an international flight, according to SFDPH.

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"Countries with large measles epidemics currently include Philippines, Indonesia, Israel, Ukraine, Romania, Brazil, and much of Western Europe," they wrote.

On the national level, 2018 saw the greatest number of imported measles cases — 82 — since measles was eliminated from the U.S. in 2000, according to the Centers for Disease Control. There were 372 total cases in the U.S. in 2018.

"Measles can spread when it reaches a community in the U.S. where groups of people are unvaccinated," the CDC explains.

As of Feb. 28, 208 cases of measles had been documented in the U.S. thus far this year.

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On Friday, the Centers for Disease Control published a report examining a small measles outbreak in the Bay Area last year. The report found that the outbreak, which infected seven people starting in Santa Clara County, was limited almost exclusively to families who'd chosen to forego vaccinations for their children, including two children whose mother lied about their vaccination status when initially asked by public health investigators.

In recent years, public health alerts have had to be issued after people with measles rode Bay Area mass transit, exposing fellow riders. In 2015, two measles patients inadvertently exposed thousands of BART riders to the virus, one riding from Millbrae to San Francisco and another riding from the East Bay to San Francisco.

Clinicians are asked to report suspected cases of measles to SFDPH Communicable Disease Control at (415)-554-2830.

Filipa Ioannou is an SFGATE staff writer. Email her at fioannou@sfgate.com and follow her on Twitter