State health officials are asking people who visited a sports bar in Arvada this week to watch for symptoms after identifying two more measles cases in Broomfield residents. 

The Colorado Department of Public Health and Environment (CDPHE) said in a release Thursday that two additional cases of measles have been identified and health officials are investigating another, all in Broomfield residents. They are all household contacts of a previously-confirmed case, the release said. 

CDPHE said to prevent further spread, public health protocols require unvaccinated household members of confirmed cases to quarantine. Two of the new cases were already in quarantine due to their vaccination status, according to the release. The third person was not in quarantine because they were vaccinated. 

The release said while the measles, mumps and rubella (MMR) vaccine is highly effective, breakthrough cases can occur, especially after prolonged exposure within a household. Breakthrough cases normally experience milder symptoms and are less likely to spread the illness to other people, according to health officials.

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