State-sponsored disinformation campaigns increasingly use anti-vaccine comments to not only undermine public health but to also reduce confidence and participation in a democratic society. Despite these dangers, research has not fully explored whether anti-vaccine comments can achieve these effects. To address this gap, an online survey experiment was conducted using a national sample of 1010 U.S. adults. Participants read a mainstream news article discussing the flu vaccine that included random variations of user comments adapted from a documented state-sponsored disinformation campaign. While exposure to anti-vaccine comments did not affect participants' views of vaccines or their willingness to discuss vaccines, participants holding pro-vaccine views reported lower confidence in news organizations and viewed the journalist who authored their article as less credible. These results suggest that anti-vaccine comments may produce effects that align with the goals of state-sponsored disinformation campaigns.