José Meireles Veterinarian Professor, Faculdade de Medicina Veterinária da Universidade de Lisboa Toxoplasmosis is a disease caused by a parasite (a protozoan) called Toxoplasma gondii . It is a zoonosis , that is, a disease that can be transmitted from animals to humans; It can have serious consequences, particularly in pregnant women and immunocompromised people ; In other circumstances, in immunocompetent adults, toxoplasmosis is often asymptomatic. Toxoplasma gondii is a parasite of the intestine of cats and other felines . When cats are parasitized, they shed Toxoplasma gondii eggs in their feces and these eggs are very resistant; Cat feces can defile various places, for example gardens, pastures, vegetable production areas, among others; In cats, toxoplasmosis is almost always asymptomatic, sometimes there may be some symptoms in the shedding eggs phase. How do animals get the parasite Animals, whether cats or other domestic animals, including food producing animals, become parasitized when they eat something that has eggs or other forms of the parasite . Cats and other felines In cats and other felines, which are the main host of the parasite, the ingested eggs develop and continue their life cycle in their digestive system until eggs are eliminated in the feces again; This shedding of eggs is not constant. It takes place 5-10 days after the first contact with the parasite. Subsequently, the parasites become latent state and eggs will only be shed again if the cats become immunocompromised; Only cats and some other felines shed Toxoplasma gondii eggs in their feces. Other domestic species In other domestic species, Toxoplasma gondii eggs that are ingested develop into forms of the parasite that form cysts in muscles, nervous system and various organs; In some of these animals, abortion is the main symptom of toxoplasmosis , when females become parasitized during pregnancy; Pregnant females can also transmit the infection and the offspring are born infected. How is toxoplasmosis transmitted to people Like animals, people become infected when they contact and eat something contaminated by Toxoplasma gondii , which can be: More often, poorly washed fruits and vegetables contaminated by cat feces with eggs of the parasite; Raw or poorly cooked meat from animals with cysts of the parasite in their muscles; Other raw animal products and contaminated water; Poor hygiene care, especially of the hands, after contact with contaminated objects or places. When pregnant women become infected during pregnancy, toxoplasmosis can be transmitted to the fetus. In this case, the toxoplasmosis will be congenital, that is, it will be present at birth. Infection of women during pregnancy can also cause malformations or miscarriage. Prevent toxoplasmosis Preventing toxoplasmosis contagion includes: Measures related to the daily care of cats that live in the house; Care with foods that could be a source of infection and other general care. These measures are particularly important for pregnant women and immunocompromised people in the family, some are even specific for these groups of people. Caring for domestic cats The following measures help to prevent the spread of toxoplasmosis to people from sensitive groups, but they are also good practices for everyone who has cats at home . Prevent indoor cats from circulating freely outside, particularly when there are rats or stray cats in the neighborhood; Feed cats with dry or canned rations suitable for the species; Do not feed raw meat to cats; Change the litter in the cat box daily and dispose it in a closed bag and in the appropriate garbage container; Wear gloves when cleaning the cat box, beds and food and water containers and wash your hands well after these operations; Avoid bringing new cats home when there are pregnant or immunocompromised people in the family; Follow the veterinarian instructions regarding deworming and other measures to monitor the health of your cats. Food care and other general care These are particularly important in pregnant women and immunocompromised people . Wash raw vegetables and fruits thoroughly before eating. There are currently specific products for this washing that are frequently indicated to pregnant women and immunocompromised people; Avoid eating raw or undercooked meat or freeze the meat for some time before preparing it for eating. Freezing and boiling eliminates the parasite; Avoid raw eggs and poorly cured products; Avoid unbottled water or water of unknown origin; Wear gloves when gardening; Washing your hands well several times a day is a general measure to prevent many infections. Pregnant women and immunocompromised people must strictly follow the instructions of their physicians regarding other specific measures for the prevention and detection of this disease. The content published in the Health Guide is intended for the general public and is provided for informational and educational purposes only. It does not replace individual medical assessment, diagnosis, or personalized clinical advice from a qualified healthcare professional. The content is produced or reviewed by physicians and other healthcare professionals at Hospital da Luz and is based on the knowledge available at the time of publication or the most recent update, as indicated at the beginning of each item.
