Complications of toxoplasmosis 

For most people, toxoplasmosis causes no or few symptoms and passes without any further problems. However, some people can develop serious complications.

Serious problems are more likely to develop if you become infected while you're pregnant or if you have a weak immune system.

Some of the main complications associated with toxoplasmosis are outlined below.

Ocular toxoplasmosis

The parasite that causes toxoplasmosis can lie dormant (inactive) in the back of the eye (retina) for many years.

If it becomes active again – for example, if you receive treatment that weakens your immune system – it can cause inflammation and scarring in the eye. This is known as ocular toxoplasmosis.

Ocular toxoplasmosis can affect one or both eyes and can cause:

Medications are usually given to treat the infection, and steroids are often used to reduce any swelling in your eye. The scarring caused by toxoplasmosis will not clear up, but treatment may prevent it getting worse.

Congenital toxoplasmosis

If a woman becomes infected with toxoplasmosis for the first time during pregnancy or a few weeks before conceiving, there's a risk the infection could spread to her unborn baby. This is known as congenital toxoplasmosis.

Congenital toxoplasmosis can cause a range of problems that are either noticeable from birth or develop months or years later. The severity of the condition varies depending on when the mother became infected.

The baby's symptoms will usually be more severe if the mother is infected early on in the pregnancy, and less severe if they're infected later on.

Problems caused by congenital toxoplasmosis can include:

Early treatment of congenital toxoplasmosis may help reduce the risk of serious or long-term problems, although it cannot reverse damage that has already occurred.

Cerebral toxoplasmosis

If you have a weakened immune system and you become infected with toxoplasmosis, the infection can spread to organs such as your eyes and brain because your immune system may not be able to fight off the infection.

If toxoplasmosis begins to affect the brain, it can cause a serious and life-threatening infection called cerebral toxoplasmosis.

Signs and symptoms of toxoplasmosis encephalitis and toxoplasmosis infections in people with immune deficiency can include:

  • headaches 
  • confusion
  • poor co-ordination
  • seizures (fits)
  • a high temperature (fever) of 38C (100.4F) or over
  • slurred speech
  • ocular toxoplasmosis

Medication can be used to treat the infection and reduce swelling in the brain, although it may not be able to cure the condition completely.

Read more about treating toxoplasmosis.

Page last reviewed: 24/06/2015

Next review due: 24/06/2017