Health officials report four cases of measles linked to a restaurant at the MGM Grand Hotel in Las Vegas, where a staff member listed as “under-immunized” appears to have infected two other Emeril’s New Orleans Fish House staff members and a patron.

Measles cases in Clark County, Nevada now total nine in the first two months of 2015. While the Fish House staff member who introduced the disease to the restaurant was listed as “under-immunized,” an infant listed as too young to vaccinate is cited as the believed source of the disease a Southern Nevada Health District (SNHD) release detailed.

A fully immunized adolescent, a young child with one of the two shots in the MMR (Measles, Mumps and Rubella) series, an unvaccinated adult and an adult with unknown vaccination status make up the remaining four prior cases.

The highly infectious disease struck Disneyland in mid-December, leading to an international outbreak spreading across seven U.S. states, Mexico and Canada according to public health officials. The number of cases in California alone since the rise of the outbreak reached 130 as of numbers the California Department of Public Health released Friday. The SNHD release did not confirm whether the cases were related.

California legislators have introduced a bill that would effectively eliminate the ability of parents to opt their children out of school-required vaccinations by way of the currently allowed personal belief waiver. While rate of increase in new measles cases has appeared to slow, lawmakers in California are expected to press on with their bill.

Public health officials declared measles eliminated from the United States in 2000 and in Canada in 1998.

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