Diseases and infections can ravage various parts of our body, from our eyes to our brain, underscoring the complex interplay between health and wellbeing. This discourse delves into an intriguing case of infection, delving into the effects of toxoplasmosis on both ocular health and cognitive behavior.
A Puzzling Scenario
Let me give a scenario. A person suffering from eye blurriness, and went to the hospital for help. When he got to the hospital, it was clear that the patient didn't have any genetic or underlying health condition. When he was examined, the doctor realized that his right eye had macular edema which is a build-up of fluid in the retina, while his left eye was still working properly. It was seen that the patient suffered from an elevated creamy retinal lesion in his right eye. Since the physician was good at his job, he performed a series of tests and was able to diagnose him with Ocular Toxoplasmosis. Actually, the diagnosis was not definitive, but at least he knew he had a condition.
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Fast forward 6 months later, the case became worse with worsening vision and this could not be corrected with Pinhole Aperture or Medications. So a lensectomy was done where the ophthalmologist cut a slit into the wall of the eye and break up the materials that make up the lens using soundwaves, after which a vacuum is used to suck the shards of the lens, then replacing it with a man-made alternative. After this, the doctors were still unable to treat his condition and that left him with retina fibrosis. The retina fibrosis could lead to curtain-esque shadows over the vision and even blindness. My question is, can Toxoplasmosis lead to all this?
Unmasking Toxoplasmosis
Toxoplasmosis is caused by a single-cell parasite found everywhere around the world known as Toxoplasma gondii. The parasite has infected over 11% of the population 6 years and older in the United States, and more than 60% of some populations around the world. Toxoplasmosis comes with flu-like symptoms such as soreness in the lymph nodes, muscle aches, and pains. When it becomes severe, it can lead to damage to the eyes, brain, and other organs in the body but surprisingly enough, most people who have been infected with the parasite do not show any symptoms.
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The connection between Toxoplasmosis and Ocular Toxoplasmosis is particularly poignant. With Ocular toxoplasmosis as with the case I illustrated at the beginning, the infection affects the eye which leads to sensitivity to bright light (photophobia), reduction in visual acuity, redness of the eye, loss of vision, and permanent blindness. Infection from T.gondii is quite easy and people who have cats are even at a higher risk of getting the parasite. This is not because cats are bad, rather the only definitive host of T.gondii are members of the family Felidae (the cat family). While toxoplasmosis requires a suppressed immune system to display symptoms, Ocular toxoplasmosis does not need immune suppression to occur in the eye.
The parasite reaches maturity and reproduces in the cat, after which it releases its eggs (oocytes) through the feces of the cat. When people do not wash properly after cleaning their feces, they can get infected by the parasite. people can also get the parasite through livestock that have the parasite by not properly cooking the meat of the infected livestock. Actually, there can also be fetal transmission from mothers who have the infection to the fetus.
According to a study of over 200 papers with cases of people with Toxoplasmosis antibodies, displayed increased aggression, the risk for an automobile accident, increased ethanol consumption, and decreased reaction time to events, showing that they were less risk averse than unaffected people. Studies have also shown that there is a higher incidence of T. gondii infection in schizophrenia patients.
Toxoplasmosis has shown the multifaceted effects of the infectious agent on human health and behavior with alterations in behavior and cognition. If you are not immunocompromised, and have the parasite, you are not going to present with symptoms.
Reference
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4180574/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3346298/
https://www.cdc.gov/parasites/toxoplasmosis/epi.html
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2692860/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC117239/
https://www.researchgate.net/publication
https://journals.asm.org/doi/10.1128/mbio.02164-19
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4757034/
https://www.aao.org/eyenet/article/ocular-toxoplasmosis-a-refresher