In the United States, approximately 11% of people have been infected, while in some areas of the world this is more than 60%. Approximately 200,000 cases of congenital toxoplasmosis occur a year. Charles Nicolle and Louis Manceaux first described the organism in 1908. In 1941, transmission during pregnancy from a pregnant parent to their baby was confirmed. There is tentative evidence that infection may affect peoples behavior. Signs and symptoms
Infection has three stages:

Acute
Acute toxoplasmosis is often asymptomatic in healthy adults. However, symptoms may manifest and are often influenza-like: swollen lymph nodes, headaches, fever, and fatigue, or muscle aches and pains that last for a month or more. It is rare for a human with a fully functioning immune system to develop severe symptoms following infection. People with weakened immune systems are likely to experience headache, confusion, poor coordination, seizures, lung problems that may resemble tuberculosis or Pneumocystis jiroveci pneumonia (a common opportunistic infection that occurs in people with AIDS), or chorioretinitis caused by severe inflammation of the retina (ocular toxoplasmosis). Young children and immunocompromised people, such as those with HIV/AIDS, those taking certain types of chemotherapy, or those who have recently received an organ transplant, may develop severe toxoplasmosis. This can cause damage to the brain (encephalitis) or the eyes (necrotizing retinochoroiditis). Infants infected via placental transmission may be born with either of these problems, or with nasal malformations, although these complications are rare in newborns.
This PCR technique utilizes the 5 nuclease activity of Taq DNA polymerase to cleave a nonextendible, fluorescence-labeled hybridization probe during the extension phase of PCR. A second fluorescent dye, e.g., 6-carboxy-tetramethyl-rhodamine, quenches the fluorescence of the intact probe. The nuclease cleavage of the hybridization probe during the PCR releases the effect of quenching resulting in an increase of fluorescence proportional to the amount of PCR product, which can be monitored by a sequence detector.Toxoplasmosis cannot be detected with immunostaining. Lymph nodes affected by Toxoplasma have characteristic changes, including poorly demarcated reactive germinal centers, clusters of monocytoid B cells, and scattered epithelioid histiocytes. The classic triad of congenital toxoplasmosis includes: chorioretinitis, hydrocephalus, and intracranial arteriosclerosis. Other consequences include sensorineural deafness, seizures, and intellectual disability.Congenital toxoplasmosis may also impact a childs hearing. Up to 30% of newborns have some degree of sensorineural hearing loss. The childs communication skills may also be affected. A study published in 2010 looked at 106 patients, all of whom received toxoplasmosis treatment prior to 2.5 months. Of this group, 26.4% presented with language disorders. Treatment
Treatment is recommended for people with serious health problems, such as people with HIV whose CD4 counts are under 200 cells/mm3. Trimethoprim/sulfamethoxazole is the drug of choice to prevent toxoplasmosis, but not for treating active disease. A 2012 study shows a promising new way to treat the active and latent form of this disease using two endochin-like quinolones.