(CNN) —  

Pete Buttigieg’s campaign sought to clarify the South Bend Mayor’s position on vaccines on Wednesday after an initial statement said the 2020 Democratic presidential candidate supported some religious and personal exemptions.

Buttigieg’s initial statement drew criticism from Democratic activists and some journalists online, with some accusing the mayor’s campaign of standing with anti-vaccination proponents – also known as anti-vaxers – who choose not to vaccinate their children for a number of reasons.

“Pete does support some exceptions, except during a public health emergency, to prevent an outbreak,” a spokesperson for Buttigieg told Buzzfeed News for a piece that published on Tuesday. “These exemptions include medical exemptions in all cases (as in cases where it is unsafe for the individual to get vaccinated), and personal/religious exemptions if states can maintain local herd immunity and there is no public health crisis.”

But early on Wednesday, a spokesperson looked to clean up that statement by emphasizing “there is no evidence that vaccines are unsafe.”

“Pete believes vaccines are safe and effective and are necessary to maintaining public health. There is no evidence that vaccines are unsafe, and he believes children should be immunized to protect their health,” the spokesperson said in a statement to CNN. “He is aware that in most states the law provides for some kinds of exemptions. He believes only medical exemptions should be allowed.”

Vaccinations have risen as a political issue in recent years as public health agencies have documented an increase in vaccine-preventable diseases, like measles. According to federal officials, there have been more than 700 cases of measles in the US this year. New York’s outbreak is approaching 7 months, making it the longest and largest outbreak in the US since the disease was declared eliminated in 2000, according to the Center for Disease Control.

President Donald Trump, who has been skeptical of vaccines at times, last week said, “They have to get the shots. The vaccinations are so important. This is really going around now. They have to get their shots.”

“Massive combined inoculations to small children is the cause for big increase in autism,” he claimed in 2012, though the Centers for Disease Control and Prevention has declared that there is no link between vaccines and autism.

He made a similar argument in 2014, tweeting, “Healthy young child goes to doctor, gets pumped with massive shot of many vaccines, doesn’t feel good and changes - AUTISM. Many such cases!”

CNN’s Maegan Vazquez contributed to this report.