YOUR HEALTH: Why one STD can have a lasting impact for women

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SAN ANTONIO, Texas – Texas researchers searching for a vaccine against the sexually transmitted disease known as Chlamydia made a huge unexpected discovery in a disease that so often goes undiagnosed by the people who are infected.

"When I was with my new partner, he had noticed some I think just some changes in my genital area." admitted one patient at UT Health San Antonio.

Her Chlamydia was easily cured with antibiotics, but this new research aims to prevent it.

It's been called the silent sexually transmitted disease, with more than a million and a half infected in the U.S. alone.

Using mice in a controlled setting, scientists studied Chlamydia transmission and discovered where the bacteria develops in the body makes a difference.

NEW RESEARCH:   Researchers at UT Health San Antonio initially tried to understand Chlamydia biology using the mouse model and accidentally found that first exposure to Chlamydia actually made the mice more resistant to chlamydial infection in the genital tract, just like vaccination.  They are using this finding to develop a live attenuated oral vaccine. In this way, even if the GI tract Chlamydia is accidentally introduced into the genital tract by human behaviors, the attenuated vaccine strain won`t be able to cause diseases in the genital tract. Infecting mice with a mouse strain of chlamydia is an appropriate model for learning information on how human chlamydia strains behave in humans.'

"We have strong evidence showing that if you expose the chlamydia in the gut first, you essentially have vaccination against subsequent chlamydia exposure," explained Biomedical researcher Dr. Guangming Zhong.

But researchers say if the genital tract is exposed to chlamydia first, the disease develops, and can be harmful.

Most people who have Chlamydia have no symptoms.   If you do have symptoms, they may not appear until several weeks after you have sex with an infected partner.

Dr. Zhong says researchers are exploring the idea of some day delivering Chlamydia bacteria as an oral vaccine.   Meaning this STD with hidden dangers, shame and a serious stigma, might someday be eliminated and spare others the uncomfortable conversation that follows the diagnosis.

"The really impactful part was telling the last partner, being we were no longer together, and we didn't have that trust," says one patient.

"We didn't have that caring for one another.   It's an important part of STDs, is telling the last partner you were with, so it doesn't continue to just spread."

Human exposure to the STD can happen through genital or oral sex with an infected partner.

If this story has impacted your life or prompted you or someone you know to seek or change treatments, please let us know by contacting Jim Mertens at or Marjorie Bekaert Thomas at

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