Moreover, some evidence suggests this loss of aversion may be specific to feline odors: when given a choice between two predator odors (cat or mink), infected rodents show a significantly stronger preference to cat odors than do uninfected controls.In rodents, T. gondii–induced behavioral changes occur through epigenetic remodeling in neurons associated with observed behaviors; for example, it modifies epigenetic methylation to induce hypomethylation of arginine vasopressin-related genes in the medial amygdala to greatly decrease predator aversion. Similar epigenetically induced behavioral changes have also been observed in mouse models of addiction, where changes in the expression of histone-modifying enzymes via gene knockout or enzyme inhibition in specific neurons produced alterations in drug-related behaviors. Widespread histone–lysine acetylation in cortical astrocytes appears to be another epigenetic mechanism employed by T. gondii.T. gondii-infected rodents show a number of behavioral changes beyond altered responses to cat odors. Rats infected with the parasite show increased levels of activity and decreased neophobic behavior. Similarly, infected mice show alterations in patterns of locomotion and exploratory behavior during experimental tests. These patterns include traveling greater distances, moving at higher speeds, accelerating for longer periods of time, and showing a decreased pause-time when placed in new arenas. Infected rodents have also been shown to have lower anxiety, using traditional models such as elevated plus mazes, open field arenas, and social interaction tests. Marine mammals
A University of California, Davis study of dead sea otters collected from 1998 to 2004 found toxoplasmosis was the cause of death for 13% of the animals.
If the fetus has been infected, the pregnant woman can be treated with pyrimethamine and sulfadiazine, with folinic acid, after the first trimester. They are treated after the first trimester because pyrimethamine has an antifolate effect, and lack of folic acid can interfere with fetal brain formation and cause thrombocytopaenia. Infection in earlier gestational stages correlates with poorer fetal and neonatal outcomes, particularly when the infection is untreated.Newborns who undergo 12 months of postnatal anti-toxoplasmosis treatment have a low chance of sensorineural hearing loss. Information regarding treatment milestones for children with congenital toxoplasmosis have been created for this group. Epidemiology
T. gondii infections occur throughout the world, although infection rates differ significantly by country. For women of childbearing age, a survey of 99 studies within 44 countries found the areas of highest prevalence are within Latin America (about 50–80%), parts of Eastern and Central Europe (about 20–60%), the Middle East (about 30–50%), parts of Southeast Asia (about 20–60%), and parts of Africa (about 20–55%).In the United States, data from the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2004 found 9.0% of US-born persons 12–49 years of age were seropositive for IgG antibodies against T. gondii, down from 14.1% as measured in the NHANES 1988–1994. In the 1999–2004 survey, 7.7% of US-born and 28.1% of foreign-born women 15–44 years of age were T. gondii seropositive. A trend of decreasing seroprevalence has been observed by numerous studies in the United States and many European countries.