The number of measles cases nationwide continues to rise, but not as dramatically as it has in recent weeks.

The U.S. Centers for Disease Control and Prevention reports there have been 880 measles cases since the beginning of the year.

Oklahoma has joined the list of 24 states with measles cases. New York has been impacted the most, with more than 700 cases.

Some states, such as Connecticut and Maine, are working to limit reasons parents can cite for not vaccinating their children. And two weeks ago, Washington’s governor signed a law that says parents with children going to daycare or school will no longer be able to claim personal or philosophical objections to the measles, mumps and rubella vaccine.

Lawmakers in Oregon were considering similar legislation, but a bill was killed in the Senate to make way for a tax on large businesses in that state.

The measles virus lives in the nose and throat of an infected person. And it’s so contagious that it can live in an area up to two hours after an infected person coughs or sneezes.

“If other people breathe the contaminated air or touch the infected surface, then touch their eyes, noses or mouths, they can become infected,” according to the CDC’s website.

FOLLOW NBC HEALTH ON TWITTER & FACEBOOK