What is toxoplasmosis?
This is an infection caused by a parasite called toxoplasma. It is not a virus and transmission is through eating contaminated food - especially meat products.
Who is at risk of acquiring toxoplasmosis?
Everybody; but some people are at more risk than others. Eggs of toxoplasma are found in cat faeces and therefore cat keepers and those whose food is exposed to contamination by cat faeces will be at increased risk.
Likewise, eating undercooked (or raw!) meat may also lead to infection, as a small percentage of lamb, pork and beef samples are found to contain the cysts. These can be found in milk and eggs as well. All are destroyed by cooking. In theory, blood transfusion is also a risk factor; but in practice, this is exceedingly unlikely as a source, since all blood and blood products are screened.
How can a mother know or suspect if she has the toxoplasmosis infection?
It is very difficult. Most people will have no symptoms at all. A few may have a mild flu-like illness, usually ignored. This may be accompanied by slight swelling of the lymph glands in the neck. All these clear up by themselves without treatment in days or weeks. The exception to this pattern is in patients with low immunity, e.g. following transplants, or those with AIDS, where the infection may be quite dramatic, even fatal.
Anything between 25 to 50 per cent of women of childbearing age have evidence of having had the infection in the past.
What kind of damage do toxoplasma-infected infants have?
There could be combination of features including damage to the eyes (chorioretinitis), a small or big fluid-filled head and/or brain damage. As mentioned before, the clinical picture tends to be variable, ranging from mild and almost unrecognizable, to very severe, bordering on incompatibility with life.
Other features may include enlargement of the liver and spleen, jaundice and seizures.
Later on, the child may be found to be deaf, sometimes with learning difficulties.
Even though incidence of infection to the fetus is highest in the later phase of pregnancy, the fetus infected in the earlier phase has the highest risk of severe damage.
Toxoplasma chorioretinitis. The sort of eye lesion seen in congenital toxoplasmosis