Which ways can be contracted toxoplasmosis?
Man can contract toxoplasmosis in different ways.
Infections are mainly acquired by gold-fecal ingestion of mature oocysts of Toxoplasma gondii present in soil, water or vegetables contaminated with faeces of infected cats. Handling of litter for domestic cat faeces or normal gardening activities may expose you to the risk of infection. Water contamination is a major problem, especially in developing countries, and reflects the influence of poor hygiene conditions.
However, the main sources of contamination are raw or uncooked meat from another intermediate host (e.g. lamb and game). Raw ham, salami or other pork products (especially homemade ones) are more frequently contaminated than beef. Milk from some mammals (cattle and pigs) can also carry the parasite. However, this method of infection is less frequent, as the parasites are rapidly destroyed at 50°C and are not resistant to pasteurisation.
An exception to this is transmission through arthropods (such as flies, cockroaches and earthworms, which can carry the oocysts of Toxoplasma gondii from the faeces) and through blood transfusion (or blood products) and organ transplantation. Toxoplasmosis can also be transmitted by transplacental means from the pregnant woman to the fetus.
Toxoplasmosis: risks for pregnant women
Toxoplasmosis is a major problem if it is contracted for the first time during pregnancy. Toxoplasma gondii can reach the foetus through the placenta and cause damage to the nervous system and eyes. In some cases, the infection results in preterm delivery or intrauterine death.
If the future mother had already come into contact with Toxoplasma gondii before pregnancy, however, it is not susceptible (as people who contract the disease are generally immune for the rest of their lives) and there is no risk to the fetus from subsequent infections. In Italy, it is estimated that 30-40% of women of childbearing age are already protected against toxoplasmosis.
The severity of the fetal infection depends on the time of gestation when the maternal infection occurs. The risk of serious consequences for the fetus is greater if toxoplasmosis is acquired during the first trimester of pregnancy.
Before pregnancy, it is therefore important to perform a blood test to assess the presence of antibodies specific for toxoplasmosis (Toxo test) and know your immune status against the parasite.
In the event that the detection of anti-Toxoplasma antibodies gives a negative result (therefore the pregnant woman is not protected against toxoplasmosis) it is important to follow some hygienic precautions to reduce the risk of infection and to undergo the Toxo test periodically. Early diagnosis and treatment with antibiotics of the future mother can prevent or reduce fetal damage.
How to prevent toxoplasmosis?
The prevention of toxoplasmosis requires the application of simple hygiene measures. If there is a cat in the home, it is not necessary to remove it, but it is sufficient to feed it only with dry or well-cooked food and clean the litter tray daily. This last operation allows to eliminate also the oocysts of Toxoplasma gondii eventually present, before they become infectious (this happens about 2-3 days after the deposition of the feces, at an ambient temperature of 24°C). Always wear latex gloves when cleaning the litter tray. However, it should be remembered that not all cats are carriers of toxoplasmosis; instead, it is necessary to pay attention to possible contact with stray animals, more commonly infected by Toxoplasma gondii.
To reduce the possibility of contracting toxoplasmosis during pregnancy, it is advisable to eat only well cooked meat, avoid sausages (cured meats and raw ham; cooked ham and mortadella are allowed) and drink pasteurised milk. Toxoplasma gondii can be destroyed in about 3-4 minutes by cooking temperatures of at least 60-67°C. Moreover, the parasite cannot withstand salting (1-2 weeks), smoking (12-72 hours) and freezing at -12.5°C (24 hours).
Before consumption, wash fruit and vegetables thoroughly, especially when harvested in vegetable gardens where cats have free access. Wear gloves to handle raw meat, poultry, fish, fruit and vegetables, flowers, soil (e.g. gardening) and any other potentially contaminated material.
In any case, always wash well with soap and water the surfaces and kitchen utensils used and avoid bringing dirty hands to the mouth, especially after touching the cat.