Stigmatization may have once served to protect early humans from infectious diseases, but that strategy may do more harm than good for modern humans, according to Penn State researchers.

"The things that made stigmas a more functional strategy thousands of years ago rarely exist," said Rachel Smith, associate professor of communication arts and sciences and human development and family studies. "Now, it won't promote positive health behavior and, in many cases, it could actually make the situation worse."

Stigmatizing and ostracizing members stricken with infectious diseases may have helped groups of early humans survive, said Smith, who worked with David Hughes, assistant professor of entomology and biology. Infectious agents thrive by spreading through populations, according to Smith and Hughes, who published an essay in the current issue of Communication Studies.

For early humans, a person who was stigmatized by the group typically suffered a quick death, often from a lack of food or from falling prey to a predator. Groups did not mix on a regular basis, so another group was unlikely to adopt an ostracized person. Infectious disease stigmas may have evolved as a social defense for group-living species, and had adaptive functions when early humans had these interaction patterns.

However, modern society is much larger, more mobile and safer from predators, eliminating the effectiveness of this strategy, according to Smith.

"In modern times, we mix more regularly, travel more widely, and also there are so many people now," Smith said. "These modern interaction patterns make stigmatization unproductive and often create more problems."

Hughes studies disease in another successful society, the ants, which have strong stigma and ostracism strategies that serve group interests at the cost to individuals.

"Ants are often held up as paragons of society and efficiency but we certainly do not want to emulate how they treat their sick members, which can be brutal," said Hughes.

Stigmatization could actually make infectious disease management worse. The threat of ostracization may make people less likely to seek out medical treatment. If people refuse to seek treatment and go about their daily routines, they may cause the disease to spread farther and faster, according to the researchers, who are both investigators in the Center of Infectious Disease Dynamics in Penn State Huck Institutes of the Life Sciences.

Stigmatization may harm a person's ability to survive a disease. Ostracization may increase stress, lessening the body's ability to fight off diseases and infections.

"People are very sensitive to rejection and humans worry about being ostracized," said Smith. "These worries and experiences with rejection can cause problematic levels of stress and, unfortunately, stress can compromise the immune system's ability to fight off an infection, accelerating disease progression."

Once applied, a stigma is difficult to remove, even when there are obvious signs that the person was never infected or is cured. Health communicators should make sure they intentionally monitor if their public communication or intervention materials create or bolster stigmas before using them, Smith said.

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