Toxoplasmosis

What is Toxoplasmosis?

Toxoplasmosis is a disease caused by the parasite Toxoplasma gondii and is known to affect most warm-blooded animals, including humans.  Cats are recognised as the primary host of the parasite which causes toxoplasmosis, however, you are most likely to become infected by eating infected meat which has not been properly cooked, unwashed vegetables or gardening.

What are the symptoms of Toxoplasmosis in humans?

Symptoms you may see are:-

• Listlessness
• Fever
• Sore throat
• Enlarged lymph nodes
• Nausea
• Inflammation of the heart (less common)

Symptoms are usually very mild, and most people will not realise they have had it, although some will experience mild flu like symptom. If you have symptoms you are most likely to get better without medication.  Once you have had Toxoplasmosis you will be immune for life

What causes Toxoplasmosis?

Cats are the only mammals in which toxoplasma is passed through the faeces. A cat develops toxoplasmosis by ingesting the parasite through contaminated matter.  The parasite lives and multiplies in the intestine where, for about 2 weeks after having infected its host, it reproduces immature egg-like forms (oocysts) which leave the cats body in the cat’s faeces.  The oocysts can then be ingested by other animals where they migrate to the muscle and brain tissue.  When a cat eats this infected meat, or prey, the life cycle is repeated.

The oocysts must be in the environment for at least 48 hours before they are infective but can survive in the environment for several years and are resistant to most disinfectants.

What puts a person at risk of Toxoplasmosis?

You are most likely to become infected from contaminated meat or soil.  Most infections are from handling raw meat, eating meat which has not been properly cooked, unwashed fruit and vegetables or from gardening. You are less likely to become infected from petting a cat, through cat bites/scratches or from handling cat faeces, although good hygiene procedures should always be followed.

Toxoplasmosis is usually harmless but does pose a great danger to an infected pregnant woman’s foetus and to people with a suppressed immune system.  If the infection passes to a baby early in pregnancy, miscarriage is common. If infection occurs between 10-24 weeks, the baby may have serious or fatal congenital defects. Most infected women will not experience any symptoms.

Diagnosis

Diagnosis is most commonly made using blood tests.

If you are pregnant and you test positive for toxoplasmosis, your GP can refer you for more tests to see if your baby has been infected. This is, however, very rare. The baby charity Tommy’s has more advice on toxoplasmosis and pregnancy, please follow the link for more information.

What treatments are there for Toxoplasmosis?

If you believe you have toxoplasmosis and you are pregnant, or have a weak or suppressed immune system, see your GP.

Toxoplasmosis can be treated with medication to prevent infection and stall the spread of disease.

How can I prevent getting Toxoplasmosis?

Do not feed your cat raw meat or unpasteurised goats milk.

If your cat uses a litter tray, faeces should be removed daily.  Fresh faeces is not infectious as it takes at least 48 hours for the organism to develop and become infectious, nevertheless, proper hygiene procedures should be observed i.e. wear gloves and wash hands thoroughly. If you are pregnant, ask someone else in the household to maintain the litter tray.

If you have dogs, they should not be allowed to get access to the cat’s litter tray.

Wear gloves while gardening.

Wash your hands before preparing food and eating.

Wash all fruit and vegetables thoroughly before preparing

Thoroughly clean all chopping boards, surfaces and utensils used to prepare raw meat.

In addition to the above precautions, pregnant women should not eat raw or undercooked meat, cured meats like salami or Parma ham, unpasteurised goat’s milk or unpasteurised goat’s milk products. They should also not touch or handle lambs or pregnant sheep.