INTRODUCTION

Toxoplasmosis is a disease caused by the parasite Toxoplasma gondii. More than 60 million people in the United States have this parasite. Most of them do not get sick. But the parasite causes serious problems in some people. These include people with weakened immune systems and babies born to mothers who were infected during pregnancy. Problems can include damage to the brain, eyes and other organs.

WHAT IS TOXOPLASMOSIS?

Toxoplasmosis is an infection caused by a parasite called Toxoplasma gondii. People often get this infection from eating undercooked meat. You can also get it from contact with cat faeces. The parasite can be passed to the baby during pregnancy.

Most people infected with this parasite have no symptoms. Some have flu-like symptoms. The severe form of the disease most often affects infants and people with weakened immune systems. Toxoplasmosis during pregnancy can cause miscarriage and birth defects.

Most infections do not need treatment. In more severe cases, such as in pregnant women, people with weakened immune systems, or newborns, treatment with drugs is indicated. There are several measures to prevent toxoplasmosis that can reduce the risk of infection.

HOW IS TOXOPLASMOSIS SPREAD?

Toxoplasma gondii is a parasite that can infect most animals and birds. It can only carry out the complete reproduction cycle in domestic and wild cats. These are the main hosts of the parasite.

Immature eggs, an intermediate stage of reproduction, can be found in cat faeces. This immature egg allows the parasite to move up the food chain. It can move from soil and water to plants, animals and humans. Once the parasite has a new host, the reproduction cycle continues and infection occurs.

If you are in good health, your immune system keeps the parasites under control. They stay in the body, but are not active. This usually provides lifelong immunity. If you are exposed to the parasite again, your immune system may eliminate it.

If the immune system is later weakened, parasite reproduction can start again. This causes a new active infection that can lead to serious illness and complications.

People usually get a toxoplasma infection through one of the following routes:

• Cat faeces containing the parasite. Cats that hunt, roam outside or eat raw meat are more likely to carry the toxoplasma parasite. You can become infected if you touch your mouth after touching something that has been in contact with cat faeces. This can happen when gardening or cleaning a litter box, so clean up with gloves and a mask, although you would actually get it from cat faeces if you put it in your mouth.
  
  
• Contaminated food or water. Undercooked beef, lamb, pork, venison, poultry and seafood are known carriers of the parasite. Unpasteurised goat's milk and untreated drinking water can also be carriers.
  
  
• Unwashed fruits and vegetables. The surface of fruits and vegetables can carry the parasite.
  
  
• Contaminated cooking utensils. Parasites can be on cutting boards, knives and other utensils that come into contact with raw meat or unwashed fruits and vegetables.
  
  
• Transplantation of an infected organ or transfusion of infected blood. Rarely, toxoplasma parasites are transmitted through organ transplantation or blood transfusion.
  
  

DO ALL CATS TRANSMIT TOXOPLASMOSIS?

No, a domestic cat that stays indoors, is healthy and dewormed cannot spread toxoplasmosis because it would be free of it; it is much easier to get the parasite from badly washed vegetables or fruit.

TOXOPLASMOSIS AND PREGNANCY

During pregnancy, the mother can transmit toxoplasmosis to the foetus, known as congenital toxoplasmosis.

If the infection occurs during the first trimester, the disease is usually more severe. It can lead to miscarriage. In some babies with toxoplasmosis, severe disease can occur at birth or in early infancy. These may be some medical problems:

• Excess fluid in or around the brain, known as hydrocephalus.
• Severe eye infections
• Irregularities in the tissues of the brain
• Enlargement of the liver or spleen
  
  

Symptoms of severe disease vary. Here are some possible symptoms:

• Problems with mental or motor skills
• Blindness or other vision problems
• Hearing problems
• Seizures
• Heart disease
• Yellowing of the skin and whites of the eyes, known as jaundice
• Rash
  
  

Most babies with toxoplasmosis show no symptoms, but problems may appear later in childhood or adolescence. Here are some of them:

• Recurrence of eye infections
• Problems in developing motor skills
• Problems with reasoning and learning
• Hearing loss
• Delayed growth
• Precocious puberty
  
  

CONCLUSION

The risk of primary infection can be reduced by avoiding eating undercooked meat (heated to 60°C) or by freezing food properly. Fruits and vegetables should be washed properly.

Pregnant women with negative antibodies to the parasite should be tested for infection several times during pregnancy if they are exposed to conditions that increase the likelihood of infection.