Toxoplasmosis is caused by the parasite Toxoplasma gondii, which is found worldwide and infects many warm-blooded animals. The prevalence of infection in humans varies widely, from 7% in Navajo Indians to 94% in Guatemala. Infection occurs when trophozoites enter host cells and multiply, leading to the formation of tissue cysts that can persist for years. Transmission occurs mainly through cat feces, which become infectious after 48-72 hours. Other transmission routes include eating undercooked meat and transplacental transfer from mother to fetus. Congenital toxoplasmosis occurs when a pregnant woman is infected, leading to fetal infection. The severity of the infection depends on the gestational age and the parasite strain. Clinical manifestations include eye infections, neurological symptoms, and systemic involvement. Eye infections are common, often affecting the choroid and retina. Neurological symptoms may include meningoencephalitis, with focal lymphocytic infiltrations and calcifications. Acquired toxoplasmosis presents in three main forms: lymphadenopathy, lymphadenopathy with organ involvement, and generalized toxoplasmosis. Lymphadenopathy is the most common, characterized by enlarged lymph nodes. Generalized toxoplasmosis is more common in immunocompromised individuals. Diagnosis is often based on serological tests, with the Sabin-Feldman dye test being the most reliable but difficult to perform. Antibody titers can indicate recent infection, though they may not be reliable in long-standing infections. Treatment involves combinations of sulphonamides and pyrimethamine, or spiramycin, which are effective in controlling active infections. However, these treatments may have side effects, such as folic acid deficiency, requiring regular blood checks. Spiramycin is often preferred for lymphadenopathic toxoplasmosis due to its fewer side effects. Epidemiological studies show a rising trend in clinically apparent toxoplasmosis, with congenital infections occurring in 57-7.5 per 10,000 pregnancies in various cities. The role of cat oocysts in human infections is being studied, with transmission possibly occurring through ingestion or inhalation. Antibody tests are essential for diagnosis, and new tests like latex-agglutination are being developed for more accurate and efficient detection.Toxoplasmosis is caused by the parasite Toxoplasma gondii, which is found worldwide and infects many warm-blooded animals. The prevalence of infection in humans varies widely, from 7% in Navajo Indians to 94% in Guatemala. Infection occurs when trophozoites enter host cells and multiply, leading to the formation of tissue cysts that can persist for years. Transmission occurs mainly through cat feces, which become infectious after 48-72 hours. Other transmission routes include eating undercooked meat and transplacental transfer from mother to fetus. Congenital toxoplasmosis occurs when a pregnant woman is infected, leading to fetal infection. The severity of the infection depends on the gestational age and the parasite strain. Clinical manifestations include eye infections, neurological symptoms, and systemic involvement. Eye infections are common, often affecting the choroid and retina. Neurological symptoms may include meningoencephalitis, with focal lymphocytic infiltrations and calcifications. Acquired toxoplasmosis presents in three main forms: lymphadenopathy, lymphadenopathy with organ involvement, and generalized toxoplasmosis. Lymphadenopathy is the most common, characterized by enlarged lymph nodes. Generalized toxoplasmosis is more common in immunocompromised individuals. Diagnosis is often based on serological tests, with the Sabin-Feldman dye test being the most reliable but difficult to perform. Antibody titers can indicate recent infection, though they may not be reliable in long-standing infections. Treatment involves combinations of sulphonamides and pyrimethamine, or spiramycin, which are effective in controlling active infections. However, these treatments may have side effects, such as folic acid deficiency, requiring regular blood checks. Spiramycin is often preferred for lymphadenopathic toxoplasmosis due to its fewer side effects. Epidemiological studies show a rising trend in clinically apparent toxoplasmosis, with congenital infections occurring in 57-7.5 per 10,000 pregnancies in various cities. The role of cat oocysts in human infections is being studied, with transmission possibly occurring through ingestion or inhalation. Antibody tests are essential for diagnosis, and new tests like latex-agglutination are being developed for more accurate and efficient detection.