STIs and the Eyes

STIs and the Eyes

While sexually transmitted infections (STIs) typically affect the genital area, on occasion, they can affect other areas of the body such as your eyes. It’s not something we really want to think about and fortunately, it’s not overly common in the USA, but eye infections as a result of sexually transmitted diseases do exist.

How Does This Happen?

STIs infect mucosal surfaces around the body, which, among other places, can be found in the genitals, mouth, nasal passages, and the eyes. Transmission of an STI into the eyes is most common in newborn babies during birth. A mother with an STI may pass the bacteria or virus onto her baby as it goes through the birth canal. Untreated, these neonatal eye infections can be severe and even cause permanent blindness. However, nowadays, pregnant women with STIs are offered treatment prior to giving birth to avoid exposing the baby to infection.

In adults, an STI-causing pathogen is most commonly transferred from the genitals to the eyes simply through touching infected bodily fluids and then touching the face or eyes.

The rate of STI-related eye infections is thought to be increasing across the States, possibly due to an increase of STIs themselves. Between 2017 and 2021, the CDC reported an increase in gonorrhea cases by 28%, while the number of syphilis cases increased by a whopping 74%.

Types of STIs in the Eyes

While not all sexually transmitted diseases have the potential to cause an eye infection, the most common ones – chlamydia, gonorrhea, and syphilis – can.


Chlamydia is caused by infection of the bacterium, chlamydia trachomatis. As an infection of the genital area, chlamydia may actually be asymptomatic in as high as 96% of cases, though can be associated with serious complications such as infertility.  As an infection of the eyes, it can cause a severe conjunctivitis, resulting in scarring and potential blindness. In the developing world where general hygiene is low, chlamydial conjunctivitis is cited as one of the leading infectious causes of vision loss. Symptoms of chlamydial conjunctivitis include:

  • Redness of the eye
  • Swelling of the eyes and eyelids
  • Itching, gritty sensation, or irritation
  • Blurred vision
  • Sticky mucous discharge
  • Droopy upper eyelid

Chlamydial conjunctivitis is treated with antibiotics, whether topical eye drops or oral tablets.


Gonococcal eye infections are most commonly found in newborn babies as they pass through that infected birth canal or even if some of the mother’s bodily fluids touch the baby during a caesarean delivery. It results in a particularly gunky form of conjunctivitis that can lead to vision loss without timely treatment. Similar to chlamydia, gonorrhea of the genital area can often be asymptomatic. Gonococcal conjunctivitis, on the other hand is very much symptomatic:

  • Profuse mucus discharge from the eyes
  • Severe redness
  • Swelling of the eyes and eyelids
  • Sensitivity of the eyes

Untreated, gonococcal conjunctivitis can progress to meningitis, an infection around the brain and spinal cord. Antibiotics are the mainstay of treatment for gonorrheal infections.


Though less common than chlamydial or gonococcal conjunctivitis, syphilis infections of the eye have increased significantly in the last several years. Unlike the previous two bacterial infections, the syphilis bacteria, treponema pallidum, can invade the bloodstream, spreading to the eye and even central nervous system. Ocular syphilis is found in tandem with HIV infection in about half of all cases. Symptoms of ocular syphilis include:

  • Redness
  • Sore eyes
  • Sensitivity to light
  • Blurred vision
  • Pupil abnormalities

Without treatment with intravenous penicillin, syphilis can lead to blindness and permanent vision loss. You may also need steroid eye drops to manage the inflammation triggered by syphilis in the eye.


It’s possible that you have the herpes virus without realizing – cold sores are caused by herpes simplex type 1. Almost 70% of the world’s population carry this strain of the virus around with them. Herpes simplex type 2 is more commonly associated with genital herpes. The herpes virus is one of those that never ever leave you once they’ve got you. Instead, they tend to lie dormant until a cold sore or two pops up front and center on your lip.

In the eye, the virus can affect any area but is most common on the cornea, the clear dome at the front of the eye. Symptoms include:

  • Soreness
  • Watering
  • Redness
  • Light sensitivity
  • Blurred vision

If severe and left untreated, it can cause corneal scarring and permanent vision loss. Antivirals such as acyclovir ointment (also used to manage cold sores) are the most common treatment, though you may also require preventative antibiotics or a steroid eye drop to manage certain types of herpes eye infections.

If you believe you may have an STI related eye infection, please contact us so that we can schedule a consultation with Dr. Michel.