(CNN) There have been 626 cases of measles reported in the United States this year, according to the Centers for Disease Control and Prevention. That's 71 more than the agency reported last week in its weekly update.

Just four months into the year, the number of cases is only 42 away from surpassing the record of 667 cases in 2014, the highest number since the illness was declared eliminated in the United States in 2000.

"In the coming weeks, 2019 confirmed case numbers will likely surpass 2014 levels," the agency said on its website Monday.

Iowa and Tennessee reported cases for the first time this week, bringing the total number of states reporting measles this year to 22. The other states are Arizona, California, Colorado, Connecticut, Florida, Georgia, Illinois, Indiana, Iowa, Kentucky, Maryland, Massachusetts, Michigan, Missouri, Nevada, New Hampshire, New Jersey, New York, Oregon, Tennessee, Texas and Washington.

New York is the state with the highest number of cases this year; health officials there are trying to contain what has become the longest ongoing outbreak in the country since 2000. The outbreak in ultra-Orthodox Jewish neighborhoods began in October when, according to officials, an unvaccinated child became infected while visiting Israel.

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