- If you are handling litter trays, wash gloves and hands thoroughly afterwards.
- Do not handle lambing ewes and do not bring lambs into the house.
- Cats are the only animals that can shed this parasite in their faeces. Provided precautions are taken, cats are not a particular risk to a pregnant woman. Like human adults, cats can sometimes, but not always, become sick when infected with the toxoplasmosis infection, so care of a sick cat should be left to someone else.
The effects of toxoplasmosis
Toxoplasmosis does not usually cause any symptoms and in most cases a person does not realise they have caught the infection. It can cause symptoms similar to flu or glandular fever, sometimes including swollen lymph nodes. Once a person has had the disease they are generally thought to be protected for life, unless they suffer an impairment of their immune system.Toxoplasmosis can be dangerous to humans if their immune system is underdeveloped or compromised, as in the case of an unborn baby, somebody with HIV/AIDS or on immuno-suppressant drugs. In such cases, the immune system is unable to restrict the spread of the parasite, which can then cause damage.
Toxoplasmosis during pregnancy
Toxoplasmosis is only a risk to an unborn baby if caught for the first time during pregnancy or within a few weeks prior to conception. An unborn baby who contracts the disease is said to have congenital toxoplasmosis. The degree of risk to the fetus, and the damage caused, depends on when in pregnancy the mother acquired the infection.If you catch toxoplasmosis for the first time during pregnancy, it does not necessarily mean that your baby will be infected. On average, only four in ten of such infections will pass to the unborn baby. Caught during pregnancy, toxoplasmosis can cause: miscarriage, stillbirth or damage to the baby’s brain and other organs, particularly the eyes. However, most babies born with toxoplasmosis have no obvious damage at birth but develop symptoms, usually eye damage, during childhood or even adulthood. A few will have more serious symptoms such as blindness or brain damage.
Testing for toxoplasmosis during pregnancy
The toxoplasmosis blood test involves taking blood from the mother and does not affect the baby. The blood tests look for antibodies to Toxoplasma. These are the antibodies produced by the body to fight the toxoplasma infection. Depending on what type of antibodies are found, and whether levels are rising, falling or stable, it’s possible to estimate when the infection took place. Local laboratories may refer blood to the Toxoplasma Reference Laboratory to carry out these tests.
Who might have a toxoplasmosis blood test?
You might consider having a blood test for toxoplasmosis if, for example:
- You think you might have put yourself at risk of catching toxoplasmosis (for example, by eating raw meat or meat that has not been cooked thoroughly).
- You are concerned about symptoms (which can sometimes be a bit like flu).
- You would like to know whether you have developed immunity to Toxoplasma.
If you feel you may have put yourself at risk in pregnancy or would like to know your antibody status prior to pregnancy, you should discuss the benefits and problems of testing with your GP, midwife or obstetrician. If it is necessary, a blood test will be taken.
At what point is a toxoplasmosis blood test conducted?
Blood tests for toxoplasmosis can be done at any stage before or during pregnancy. The blood test can usually only show possible infection two to three weeks after any risk incident, as it can take this long for antibodies to be detectable.The blood test involves taking a small amount of blood from the mother. There isno risk to the unborn baby. The blood test aims to show whether certain antibodies indicating toxoplasmosis are present or not, and, if they are present, to determine whether they are there due to a current or a previous infection.If the tests show that the infection is current or recent, there is a risk that the baby will be infected. The obstetrician or GP will make a recommendation about any further action that might be required. It may take several weeks for the infection to pass from you to your baby. The degree of risk and severity of damage depends on when you were infected.
What do my toxoplasmosis blood test results mean?
A negative result
A negative result means that you have never had toxoplasmosis, are not immune, and need to take precautions to avoid infection before conceiving and during pregnancy.
A positive resultA positive result means that you had toxoplasmosis at some time in your life. Many pregnant women will have a positive result because they contracted toxoplasmosis in the past and built up an immunity before getting pregnant (antibody screen IgG positive). If the test is antibody screen IgM positive, this indicates a current or recent infection. The blood must be sent on from the local laboratory to the Toxoplasma Reference Laboratory, for confirmation and further testing. The Toxoplasma Reference Laboratory will then send the results to your midwife or doctor, who will pass the information to you.A small percentage of tests will appear positive when in reality a woman has never had the disease.