Toxoplasmosis – Symptoms and Causes
What Is Toxoplasmosis?
Toxoplasmosis is an infection caused by the parasite Toxoplasma gondii. People typically get infected by eating meat that isn’t fully cooked or through contact with cat waste. The infection can also pass from a pregnant mother to her unborn baby.
Most infected people don’t show any symptoms. When symptoms do appear, they often feel like the flu. The infection is usually more dangerous for babies, pregnant women, and people with weak immune systems.
During pregnancy, it may lead to miscarriage or birth defects.
For most healthy adults, no treatment is needed. However, doctors prescribe medications for pregnant women, newborns, people with serious symptoms, and those with weakened immune systems.
People can reduce their risk by taking simple preventive steps like washing hands after gardening or handling raw meat.
Signs and Symptoms
Eye Disease Indicators
People with toxoplasmosis affecting the eye may experience several uncomfortable symptoms. Pain in the eye is common, and vision may become blurry or poor. Many notice floaters—small dark spots that seem to drift across their field of vision.
Without proper treatment, this eye infection can lead to blindness. The parasites can damage the retina and other important eye tissues. Even people with healthy immune systems can develop eye problems from toxoplasmosis.
Impact on Those with Compromised Immunity
People with weakened immune systems face more serious risks from toxoplasmosis. An old infection might become active again in these individuals. This includes people living with HIV/AIDS, transplant recipients, and those undergoing cancer treatment.
In addition to severe eye problems, the infection can spread to the lungs. This may cause difficulty breathing, high fever, and a persistent cough.
Brain inflammation (encephalitis) may develop, leading to mental confusion, poor balance and coordination, weak muscles, seizure activity, and changes in alertness levels.
The infection can sometimes appear in other body tissues as well, though this is less common.
Effects on Unborn Babies and Infants
When a pregnant woman gets infected, toxoplasmosis can pass to her unborn baby. This is called congenital toxoplasmosis. Infections during early pregnancy often cause more severe problems and may lead to miscarriage.
Some babies show serious symptoms at birth or soon after, including:
- Excess fluid in the brain (hydrocephalus)
- Severe eye infections
- Brain tissue abnormalities
- Enlarged liver or spleen
Symptoms in severely affected infants may include:
| Physical Symptoms | Neurological Symptoms |
|---|---|
| Jaundice (yellowing skin) | Vision problems or blindness |
| Rash | Hearing loss |
| Heart problems | Seizures |
| Enlarged organs | Developmental delays |
Most infected babies don’t show immediate symptoms. However, problems can appear later in childhood or the teen years, such as:
- Recurring eye infections
- Delayed motor skill development
- Learning difficulties
- Hearing loss
- Growth problems
- Early puberty onset
When Medical Attention Is Needed
See your doctor if you’re concerned about exposure to toxoplasmosis, especially if you’re pregnant or planning pregnancy. A blood test can check for infection.
Seek immediate medical care if you experience serious symptoms like blurred vision, confusion, or coordination problems. These need prompt attention, particularly for those with weakened immune systems.
If you’re pregnant and think you might have been exposed to the parasite, tell your doctor right away. Early treatment can reduce the risk to your baby.
Causes
Toxoplasma gondii is a common parasite that affects many animals and birds, but only completes its full reproductive cycle in cats. This makes domestic and wild cats the primary hosts for this organism.
The infection pathway often begins with cat feces. When infected cats eliminate waste, they release immature parasite eggs that can contaminate soil, water, plants, and eventually other animals and humans.
Once inside a new host, the parasite continues its life cycle, leading to infection.
People with healthy immune systems typically keep the parasite under control. The parasites remain dormant in the body, which often creates lifelong immunity.
However, if someone’s immune system becomes compromised later in life, the parasite can reactivate and cause serious health problems.
Common Infection Sources
Contact with cat feces: Handling cat litter boxes or gardening in soil where cats have defecated can lead to infection, especially if cats hunt or eat raw meat.
- Food and water contamination: Consuming undercooked meats (beef, lamb, pork, venison, chicken, shellfish), unpasteurized goat milk, or untreated water.
- Unwashed produce: Fruits and vegetables with parasite-contaminated surfaces.
- Kitchen cross-contamination: Using cutting boards, knives, or utensils that have touched raw meat or unwashed produce without proper cleaning.
- Medical procedures: In rare cases, receiving infected organs during transplantation or contaminated blood during transfusions.
The parasite enters the body when people accidentally ingest it after touching their mouths with contaminated hands or by eating food containing the organism. People who own outdoor cats or regularly clean litter boxes face higher exposure risks.
For most healthy adults, exposure doesn’t cause noticeable symptoms. The immune system effectively contains the parasite, preventing it from causing harm. This protective response usually creates lasting immunity against future infections.
Risk Factors
The parasite exists worldwide and can affect anyone. People with weakened immune systems face higher risks of serious illness from toxoplasmosis. These include:
- HIV/AIDS patients
- Those undergoing cancer chemotherapy
- People taking high doses of steroids
- Individuals on anti-rejection medications after organ transplants
These conditions make it harder for the body to fight off the infection effectively.
Ways to Prevent Disease Spread
Cat Owner Safety Tips
Protecting yourself from toxoplasmosis requires simple precautions in your daily activities.
Always wear gloves when gardening or handling soil. Afterward, wash your hands with soap. Make sure to cook meat thoroughly. Whole meats should reach 145°F, ground meat to 160°F, and poultry to 165°F.
Avoid these high-risk foods:
- Raw or undercooked meats
- Raw shellfish (clams, mussels, oysters)
- Unpasteurized goat milk products
- Untreated water
Kitchen Safety Practices:
- Wash cutting boards and utensils with soapy water after contact with raw meats
- Clean hands before and after food preparation
- Thoroughly wash or peel all fruits and vegetables
For outdoor safety, keep children’s sandboxes covered to prevent cats from using them as litter boxes.
If you own cats, follow these guidelines:
- Keep cats indoors
- Feed them only commercial cat food (not raw meat)
- Avoid adopting stray cats, especially kittens
- Have someone else clean the litter box daily
If you must clean the litter box yourself, wear gloves and a face mask. After cleaning, wash your hands thoroughly. Pregnant women or people with weakened immune systems should be particularly careful.
These steps can lower your infection risk while you enjoy being with your cats.
