Mondays for most common sexually transmitted bacterial infection

5 February and 12 February are Chlamydia Mondays in Västerbotten Region with the aim to get more people to test themselves. Research fellow Barbara Sixt and her research group at Umeå University hope that a deep understanding of the arms race between us and the Chlamydia bacteria will ultimately allow the development of new treatments.

Published: 2024-02-05 Updated: 2024-03-25, 08:16

Chlamydia is caused by the bacterium Chlamydia trachomatis and is the most common bacterial sexually transmitted disease with more than 130 million cases every year. The infection can in some cases cause long-term damage and complications, leading for instance to chronic pain, infertility, ectopic pregnancy, or dangerous infections in newborns. Apart from causing sexually transmitted infections, the bacterium Chlamydia trachomatis can also cause the eye disease trachoma, a common cause of visual impairment and blindness in underprivileged areas of the world.

When the bacterium infects an individual, it invades the cells of its human host and can only grow in the interior of these cells. This makes this pathogen an exquisite model system to study cell-autonomous immunity, that means the intrinsic defense systems of human cells and how they may be exploited to develop new strategies to combat the pathogen. And this is what UCMR researcher Barbara Sixt, research fellow at the Department of Moelcular Biology at Umeå univeristy, and her lab members are conducting research on.

Why do you think a Day like this is important?

“It is very important to raise the general awareness of Chlamydia and other sexually transmitted infections and to provide easily accessible information on how such infections can be prevented and how one can get tested. Infections with Chlamydia trachomatis are very common, but can be easily overlooked, because they often produce only mild symptoms or none at all. However, even such mild infections can cause damage to reproductive tissues, which can affect for instance fertility. By using safe sex practices and by getting tested and treated, we can protect our own health, and also protect others by reducing the spread of the pathogen.”

Why are you working with this bacterium?

“What is probably not well known is that Chlamydia trachomatis has close relatives that do not cause diseases in humans but infect different species of animals and other living beings. As a doctoral student in my home country Austria, I studied Chlamydia-related bacteria that naturally infect amoebae. I observed that those bacteria could not infect human cells, because they could not cope with the intrinsic defense systems that human cells use to fight invading bacteria. This was quite fascinating. Hence, since that time, I am trying to understand how Chlamydia species that infect humans and cause diseases can counteract the defense mechanisms of their human host cells.”

What is the (dream) goal with your research?

“I am personally very much driven by curiosity and the wish to better understand how microbes interact with the human host. Yet, of course, our hope is that a deep understanding of the arms race between us and the microbes will ultimately also allow the development of new treatments. Chlamydia is currently treated with broad-spectrum antibiotics. Yet, a more sustainable approach would be the use of medicines that combat Chlamydia specifically without causing damage to beneficial bacteria. Exploiting the intrinsic defenses of human cells may be one way this could be achieved in the future.”

Why is there no functioning vaccine today?

“Decades of research have so far not led to the development of vaccines that can provide long-lasting protective immunity against Chlamydia trachomatis. However, this field of vaccine research is very active, and I am hopeful that the developments in vaccine technology and our rising understanding of the immunobiology of Chlamydia infections will eventually lead to a break-through.”

For more information, please contact:

Umeå Centre for Microbial Research UCMR

Umeå Centre for Microbial Research UCMR

UCMR is a Linnaeus Centre of Excellence promoting interdisciplinary cutting-edge microbial research.

Department of Molecular Biology

Department of Molecular Biology

The Department is affiliated to both the Faculty of Science and Technology and to the Faculty of Medicine.

The Laboratory for Molecular Infection Medicine Sweden

The Laboratory for Molecular Infection Medicine Sweden

MIMS is the Swedish partner in the Nordic EMBL Partnership for Molecular Medicine.

Nordic EMBL Partnership for Molecular Medicine

Supporting organisations