newspapers and magazines, including the Village Voice, The New York Native, and Outweek; some of his articles are collected in Surviving and Thriving with AIDS, published by the People with AIDS Coalition in 1988. He also appeared in German filmmaker Rosa Von Praunheim's 1990 film Positiv - Die Antwort schwuler Männer in New York auf AIDS. Opposition Despite his career and prominence as an activist, Callen was met with resentment, suspicion and opposition from others. Since he was diagnosed with AIDS in 1982 and survived over a decade, people speculated as to whether his diagnosis was real or fabricated to get attention. He responded to that criticism by releasing his medical reports and pictures of his lungs which showed his pulmonary Kaposi's Sarcoma. Additionally, Callen stood by his belief in the multifactorial theory when there was scientific proof that HIV was the cause of AIDS. Callen openly questioned the HIV theory of AIDS and was especially critical of AZT monotherapy when it was first introduced: "The HIV paradigm has produced nothing of value for my life and I actually believe that treatments based on the arrogant belief that HIV has proven to be the sole and sufficient cause of AIDS has hastened the deaths of many of my friends." Honors In June 2019, Callen was one of the inaugural fifty American “pioneers, trailblazers, and heroes” inducted on the National LGBTQ Wall of Honor within the Stonewall National Monument (SNM) in New York City’s Stonewall Inn. The SNM is the first U.S. national monument dedicated to LGBTQ rights and history, and the wall’s unveiling was timed to take place during the 50th anniversary of the Stonewall riots. Performance career Michael Callen briefly was the lead of the a cappella group Mike & the Headsets. In 1982, Callen, along with Janet Cleary, Pamela Brandt, and Richard Dworkin formed a queer rock-and-roll band called Low Life. After Low Life disbanded, Callen's solo album Purple Heart was released and quickly acclaimed as a staple of gay men's music. He was a founding member of the gay male a cappella singing group The Flirtations, with whom he recorded two albums. He also had a solo album, Purple Heart, which a review in The Advocate called "the most remarkable gay independent release of the past decade." Callen recorded two albums with The Flirtations, as well as a double disc album, Legacy, which was released by Significant