This was not what she signed up for.

A Brooklyn woman is suing a major stock-photo company after she found her image splashed across ads in city newspapers as a veritable poster child for the rights of HIV-positive people.

A perfectly healthy Avril Nolan, 25, has filed a $450,000 lawsuit against Getty Images in Manhattan Supreme Court, accusing the photo agency of improperly allowing her image to be used in the advertisements.

The ads’ implication that she had the dreaded disease has hurt her personal and professional relationships and caused her emotional distress, she says in the suit.

The suit says Nolan found out about the ad only after she was alerted by a Facebook friend and her Pilates exercise instructor to a quarter-page color ad that ran in the free AM New York newspaper on April 3.

Next to her face were the words, “I am positive (+),” and, “I have rights.”

The ad was paid for by the state Division of Human Rights.

Nolan, who works in p.r., says a New York photographer, Jena Cumbo, snapped the shot years ago but “had no written release or authorization” to use or sell it.

“Upon learning of the publication, [Nolan] became instantly upset and apprehensive that her relatives, potential romantic partners, clients as well as bosses and supervisors might have seen the advertisement,” she says in court papers.

Nolan was not in a committed relationship at the time, her attorney, Erin Lloyd, told The Post.

“Feeling humiliated and embarrassed, [Nolan] was forced to confess to her bosses that her image had been used in an advertisement for HIV services, implying that she was infected with HIV, in a newspaper often used by her own clients for advertising and that is distributed to tens of thousands of New Yorkers every day.”

The suit maintains Getty “never requested proof that [Nolan] had executed a legally enforceable and binding written model release.”

Cumbo described herself as an acquaintance of Nolan.

“I have been nothing but apologetic about how this happened,” Cumbo told The Post. “I never intended for her picture to be used in this way.”

Cumbo said that she never gave Getty a release and that the image was originally used for a magazine editorial.

Nolan attorney Erin Lloyd said the ad’s publication was a violation of privacy that breaks state law requiring signed releases for commercial images.

Getty has “eschewed its responsibility to comply with the local laws in which it operates, to the injury of New Yorkers,” Lloyd says in the suit.

Nolan is also pursuing a legal claim against the state’s Division of Human Rights.

A Getty spokeswoman declined to comment.