It's hard to believe that in the year 2000 measles was deemed eradicated in the United States. Now, thanks to "vaccine hesitancy" and the anti-vax movement, we are now seeing the greatest number of cases of the disease in the U.S. in the last 25 years.

There has been an alarming number of cases of the disease, totaling almost 700, in the United States this year alone, PBS reports, causing concern among health officials. “This is alarming,” Dr. William Schaffner, a Vanderbilt University vaccine expert, said.

The Center for Disease Control (CDC) is reporting that as of April 19, 626 individual cases of measles were reported across 22 different states. What's more shocking is that the amount of cases is up 71 cases from the previous week alone. Over the last twenty years, since measles was eradicated, 2014 had the highest number of cases of the disease with 667 reported cases for the year. The CDC predicts that we will surpass that number in the coming weeks.

States Arizona, California, Colorado, Connecticut, Florida, Georgia, Illinois, Indiana, Iowa, Kentucky, Maryland, Massachusetts, Michigan, Missouri, Nevada, New Hampshire, New Jersey, New York, Oregon, Texas, Tennessee, and Washington have all reported cases of measles to the CDC, but there are many who don't report because they simply don't have health coverage or they are worried about backlash from not vaccinating their children.

The CDC is reporting there are currently outbreaks in New York State, New York City, Washington, New Jersey, California, and Michigan. They consider an outbreak to be three or more cases of the disease. Public health officials blame misinformation about the measles vaccine for the rise in measles cases, with many still believing that the MMR vaccine is one of the causes of Autism despite that myth being debunked many times over.

“Many parents are afraid. And if you want to believe your kid doesn’t need that many shots, there’s plenty of places to find people who agree with you,” Dr. Jonathan Fielding, former head of the Los Angeles County Department of Public Health, told PBS. “It’s not so easy to discern what is real and what is not.” Unvaccinated travelers who travel to areas where the disease is still prevalent are also bringing measles back to the United States and spreading it to those who aren't vaccinated. Herd immunity is being compromised due to large groups of people who aren't vaccinating.

The CDC recommends children receive two doses of the MMR vaccine with their first dose administered anywhere between 12 and 15 months. Children then receive their second dose between the ages of four and six. Adults should also be checking to ensure they are up to date on their own MMR vaccine, as many born between 1970 and 1996 may have only received one dose and are due for a booster.

Dr. Schaffner warns that the reoccurrence of measles could signal the return of more diseases that have been eradicated, such as "rubella, chickenpox, and bacterial meningitis."

"Measles is the signal that in these communities where there's profound under-vaccination, they are susceptible to a whole menu of communicable diseases we thought were relegated to yesteryear."

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