Celebrities have long played a role in public health campaigns, raising money for research and serving as spokespeople for various causes. Even if they don’t choose to lend their names to a specific cause, by virtue of the scrutiny on their private lives, famous individuals can serve the public health community without even trying.

Last November, actor Charlie Sheen announced on the Today Show that he is HIV positive, a condition he coped with for years. Sheen came forward for personal reasons, looking to counter a smear campaign and end extortion efforts.

“I have to put a stop to this onslaught, this barrage of attacks and of sub-truths and very harmful and mercurial stories that are about me,” he said on the Today Show.

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Little did Sheen know at the time that his personal tragedy inadvertently would trigger a spontaneous public information effort around the human immunodeficiency virus (HIV) and HIV prevention, according to a study published in the latest JAMA Internal Medicine.

Sheen’s disclosure made headline news, but media outlets also covered the disease itself. Based on an analysis of news trends gathered by the researchers, usually only 12 in every 1,000 news stories in 2015 mentioned HIV. On the day of Sheen’s announcement, there was a 265 increase in news coverage related to HIV, one of the most significant media days for the disease in the past seven years.

Using Google Trends, the authors also looked at search patterns for strings related to HIV, symptoms, prevention and testing. Within hours of Sheen’s disclosure, the number of HIV-related searches spiked, a 417 percent increase over what normal search trends would produce.

“While no one should be forced to reveal their HIV status and all diagnoses are tragic, Sheen’s disclosure may benefit public health by potentially helping many learn more about HIV and HIV prevention,” lead author John W. Ayers of San Diego State University said in a statement.

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An estimated 1.2 million Americans is HIV positive, according to the Centers for Disease Control and Prevention, and an estimate one in eight is unaware of their infection.

Millions of dollars has been spent on public health campaigns, and billions more will be spent on treatment. Where education efforts fall short, celebrities may pick up the slack, as they often have a major impact on public perceptions of HIV simply by putting a nationally or internationally famous face on the disease. This has been the true Rock Hudson first announced he had AIDS, becoming the first major celebrity to die of the virus.

A 2012 article in the BMJ found that celebrities can have a positive long-term impact on public health initiatives through their involvement. Though they’re not health experts, celebrities can “often speak personally and bring compelling authenticity to public discourse,” the authors explained.

Charlie Sheen announced his illness to protect himself, but he may have also saved many others from contracting the disease he’s now coping with.