Toxoplasma gondii is an insidious microorganism, intracellular parasite. It is parasitic in cells and travels with the bloodstream, reaching all parts of the body and destroying the brain, heart, and fundus of the eyes, causing a decline in human immunity and various diseases. It is known that cats and other felines are the end hosts of Toxoplasma gondii, which is parasitized in the epithelial cells of the small intestine of these animals and forms cysts that are excreted in the feces. Both cysts and encysts are different developmental stages of Toxoplasma gondii, and they are both infectious. Almost all mammals and birds, such as rats, pigs, sheep, cows, rabbits, chickens, ducks and geese, can be infected with Toxoplasma gondii. The main source of infection in humans comes from the meat of these animals, such as shabu-shabu meat at insufficient temperature or for too short a time, raw and cooked plates not separated, and contaminated cow and goat milk can also be infected. Toxoplasma gondii infections in humans are widely distributed around the world, and surveys show that the infection rate in Western countries is much higher than in China, in some cases up to 90% or more, most likely due to their habit of eating semi-cooked beef and lamb. Dogs and other pets are intermediate hosts for Toxoplasma gondii, and feces and excrement are not contagious, so simple contact with dogs will not infect you with Toxoplasma unless you eat undercooked dog meat. People can also infect each other. Urine, saliva, tears, nasal discharge, even menstrual blood and semen of acutely infected patients can carry Toxoplasma gondii envelopes, which can be transmitted through droplet contact and sexual intercourse. Symptoms Most people infected with Toxoplasma gondii have no clinical symptoms or are so mild that they do not know when they are infected, and this infection is called latent infection. Only a few people with primary infection have clinical symptoms, such as swollen lymph nodes, fever, fatigue, headache, sore throat, muscle and joint pain, and abdominal pain, which heal themselves after a few days or weeks as the body develops immunity and has a natural immunity to Toxoplasma infection from then on. When the infected person is a patient with severe immune deficiency, such as AIDS patient or chemotherapy patient, the symptoms of Toxoplasma gondii infection can be very serious, often manifesting as encephalitis and even causing death. Third, how to prevent and control Toxoplasma gondii infection 1, pay attention to dietary hygiene, meat should be fully cooked, avoiding raw meat contamination of cooked food. 2. Cats should be kept at home, fed cooked food or finished cat food, and not allowed to catch infected rats or birds outside or eat food contaminated with cat feces and infected. 3. Pay attention to daily hygiene, remove cat feces daily and wash hands carefully after contact with animal excrement. 4. Avoid contact with cats and their feces during pregnancy unless the pregnant woman’s serum test proves that she has already had Toxoplasma gondii infection. 5.Toxoplasma gondii infection can be treated with a variety of simple and effective drugs, such as sulfonamides plus pyrimethamine, and macrolide antibiotics, etc. Treatment must be carried out according to medical advice, and timely treatment of infection in pregnant women can reduce the chance of fetal infection.