At the start of the New Year, I noted outbreaks of measles were being reported across the country.

Unfortunately for one of America’s most iconic institutions, the latest set of cases is being christened the “Disneyland Measles Outbreak”!

The number of cases from the initial infections occurring at “the happiest place on earth” is now 51…and more are expected.

The measles outbreak centered in California is rapidly expanding, with officials now confirming 51 cases of the illness — nearly double the number reported Tuesday — and warning that more people will probably fall sick with the highly contagious virus.

Officials said there was now evidence that the measles outbreak had spread beyond people who visited Disneyland between Dec. 17 and 20 and begun infecting people in the broader community.

It is the beginning of a scenario experts have feared. Health officials generally hope a measles outbreak can be contained within a manageable group of people and eventually extinguished by keeping the ill at home or in a hospital room until they recover, with the outbreak eventually being stopped by the broader community of vaccinated people.

The outbreak has been so bad in the San Diego area, it shut down an urgent care facility for a short time.

Six patients with suspected measles infections temporarily shut down the Sharp Rees-Stealy urgent care center in La Mesa Wednesday afternoon.

Frances Schnall, a Sharp communications manager, said that the six people entered the facility about 11:45 a.m.

Once it became clear that they had rashes and other measles-like symptoms, Schnall said the six were asked to cover their noses and mouths with masks and isolated from other patients in the facility’s waiting room.

…About 40 people were in the building at the time. All were asked their names and immunization histories before being released and that information was given to the county health department for follow up.

The infections are striking hardest in the wealthiest areas of the Golden State.

According to the Orange County Register, in 2014 the county had 22 cases of measles by April, nearly half of the 49 cases in the state at the time. On Wednesday, Orange County reported a measles case in an unvaccinated high schooler that was unrelated to the Disneyland outbreak.

Many anti-vaccine activists are unconvinced by the Centers for Disease Control and Prevention’s guidelines about the importance of vaccinating children against the “very contagious” measles, or its assurance that no link between the vaccine and autism has been found.

The problem isn’t limited to the OC. As the Atlantic reported in September, some Los Angeles county schools have vaccination rates “as low as South Sudan’s.” Several of the Disneyland cases involved people who were old enough to be vaccinated but hadn’t been, according to the CDPH; they included the commercial flight passenger, according to the Times.

And while getting vaccinated may have prevented some of these cases, it is being reported two of those recently infected were infants too young for the complete suite of shots. However, the quick spread of a childhood disease believed to be essentially contained within this country is now prompting the implementation of new school policies.

Orange County Health Officer Eric Handler warned that students who have not been vaccinated for measles may be excluded from attending school or day-care to prevent the further spread of the disease.

And while Walt Dinsey parks and resorts are working closely with public health officials, Mickey Mouse cannot be happy about the new moniker associated with the Anaheim theme park.

However, between the surge of unvaccinated immigrants, vaccination waivers for American children, and the ease of global travel, it probably won’t be too long before a second theme park is the epicenter for another disease outbreak.