The Department of Health and Human Services is preparing to issue a no-bid contract for a firm run by an ally of President Trump to poll Americans on their “perspectives around vaccines.”

The move follows a wide-reaching effort by the health secretary, Robert F. Kennedy Jr., to dismantle parts of the nation’s health infrastructure that develop and make recommendations for the use of vaccines. A day before the contract proposal was posted last week, Mr. Kennedy moved to fire the director of the Centers for Disease Control and Prevention because of disagreements with his vaccine policies.

The polling firm, HarrisX, is part of Stagwell, a marketing company led by Mark Penn, a former political adviser to Bill and Hillary Clinton who has now become a vocal supporter of Mr. Trump. Mr. Penn has advised Mr. Trump on polling — most recently as the president mulled getting involved in the race for New York City’s mayor.

The proposal for the no-bid contract gave few details of the plan, and did not estimate how much HarrisX would be paid, but the Health Department argued that the firm has a “unique capability to conduct a large-scale study targeting specific populations in an accelerated timeline.”

HarrisX publishes a wide variety of political polling, most prominently in presidential elections (HarrisX polls were included in The Times’s 2024 poll tracker, among hundreds of other surveys). Mr. Penn, who worked as an executive for Microsoft before founding Stagwell, made no secret of his preference for Mr. Trump while his firm worked on polling for the 2024 election, and his vocal support on social media has continued since Mr. Trump took office.

Mr. Kennedy has faced a barrage of criticism for his vaccine policies, which are rooted in his skepticism of their effectiveness and in claims — debunked in numerous studies — that vaccines cause chronic disease and autism. He has falsely claimed that mRNA vaccines offer no protection against respiratory viruses and can prolong pandemics. He also described the coronavirus shot as “the deadliest vaccine ever made.”

The no-bid contract to HarrisX gave few details of the questions that would be asked in the poll, only saying that it would seek to “understand Americans’ perspectives around vaccines and drivers of trust in making vaccine decisions.”