What is toxoplasmosis in pregnancy? Toxoplasma gondii is a tiny parasite that lives in the cells of many mammalian species and birds. Humans are only an incidental stopover for the pathogen; in order to multiply, it needs a cat as a host. In the course of their lives, a great many people come into contact with the tiny creatures – usually unnoticed. The parasites only cause serious damage in people with a weakened immune system or during pregnancy in the unborn child when the mother first becomes infected.
Symptoms of toxoplasmosis
Toxoplasma gondii is very common. If about one in three people had contact with the parasite at age 30, more than 70 percent of septuagenarians have it. In most cases, the body deals with the onslaught of parasites unnoticed. Rarely, the infection manifests itself with flu-like symptoms:
- Swollen lymph nodes
- Fever
- Fatigue
The toxoplasmas remain as cysts in the tissues. Occasionally, the parasites migrate out of their cysts, are recognized and fought by the immune system. Thus, the immune system maintains immunity for life and successfully prevents further infections.
When is toxoplasmosis dangerous?
For humans, there are two situations in which the harmless parasites become threatening pathogens: first, a weakness of the immune defense, as occurs in severe diseases, for example AIDS. Then the toxoplasmas in the cysts can spread unhindered and destroy vital organs. However, effective drugs exist for the treatment of acute toxoplasmosis. On the other hand, the parasites can also cause harm to the unborn child during pregnancy; but only if the mother becomes infected for the first time during pregnancy. In such cases, the toxoplasmas that appear en masse at the beginning of the infection may reach the uterus before they can be intercepted by the maternal immune defense force. Once there, the path to the fetus is short. Since its organism does not yet have an immune system, it is exposed to the infection without protection.
What are the consequences of toxoplasmosis for the unborn child?
Only if the mother is infected for the first time is there any risk at all for the fetus to also become infected. The magnitude of this risk, in turn, depends on the time in pregnancy at which the initial contact occurs. Exact figures do not exist, estimates are 5-15 percent in the first trimester, 30 percent in the second and over 60 percent in the last three months of pregnancy. The earlier the unborn child is affected, the more severe the consequences can be. This is because the organs form in the first weeks of pregnancy and are very sensitive to harmful influences during this time. Therefore, the brain in particular can be severely affected – resulting in calcifications, hydrocephalus and scarring. Miscarriage can also occur. If the infection only occurs in the second half of pregnancy, the newborns often have no or only minor abnormalities. Sometimes, late effects such as eye changes or developmental delays only become apparent.
How can infection be prevented?
For humans, there are two main sources of infection. The most important is raw or insufficiently heated meat, which may contain cysts with pathogens. The other is cat feces, especially if they are not very fresh, because the toxoplasmas need several days to form infectious stages. However, these can then remain contagious for months. Follow these rules to avoid initial infection as a pregnant woman:
- Do not eat or season raw meat such as pork fat or raw sausage, or untreated milk. There is an increased risk especially with meat from pigs, sheep, goats, game and poultry, and milk from cows, sheep and goats.
- Always heat meat sufficiently long – an evenly distributed temperature of at least 67 ° C for at least two minutes is recommended.
- Carefully wash or peel fruits and vegetables.
- After touching raw meat, fruits and vegetables thoroughly wash your hands and thoroughly clean used kitchen utensils.
- Do not drink unfiltered water (for example, from streams or when swimming in lakes).
- Avoid contact with cat feces; wash hands after contact with cats.
- Cover sandbox in the garden so that no cat can defecate in it and wash hands thoroughly after visiting playgrounds.
- Wear gloves when gardening and wash hands after finishing.
Cat in the household – what to consider?
Cat owners should also follow these tips during pregnancy:
- Ask family members to clean the litter box daily with hot water (at least 70 °C) – pregnant women should not do this themselves.
- Feed cat canned or dry food, instead of raw meat.
- Cat saliva is not infectious in itself, nevertheless, the cat’s mouth may have previously come into contact with feces. Therefore, wash your hands after each contact with the cat.
If a cat lives in your household, you do not have to avoid all contact with the animal during pregnancy. Since cats are very clean, you can usually pet them without hesitation, but should wash your hands thoroughly afterwards.
Toxoplasmosis: diagnosis and diagnostics.
If toxoplasmosis is suspected, the blood can be tested for antibodies. These indicate whether an infection has occurred and whether it is fresh or has been present for some time. This test can also be performed if you wish to have a child or in early pregnancy. However, it is not part of prenatal care, so it is only paid for by health insurance companies if there is a reasonable suspicion of an infection.
What to do about toxoplasmosis in pregnancy?
Pregnant women who are newly infected must be treated with medication – even if they have no symptoms. The attending physician makes the choice of antibiotic depending on the week of pregnancy; it is taken for at least four weeks. Furthermore, the specialist will assess the fetal development by means of detailed ultrasound and, if necessary – after the 20th week of pregnancy – will also arrange for an amniocentesis to check whether the pathogens have passed to the unborn child at all.
Toxoplasmosis and newborns
Immediately after birth and three times at four-week intervals, the newborn has an ultrasound of the head and an ophthalmoscopy. In addition, blood is drawn from both mother and child and examined together with cord blood and placenta in a special laboratory. The baby’s blood is then tested twice more to see if it contained only the mother’s antibodies or if it forms antibodies of its own, indicating that it has been through an infection with the risk of late damage.
