Toxoplasmosis is an ailment caused by Toxoplasma gondii, one of the most commonly encountered parasites in the world. The disease usually spreads by either eating undercooked meat, exposure to infected faeces of cats, or genetics, where it passed from the mother to the child during pregnancy. It is especially fatal during pregnancy since the parasites might be transmitted through the placenta. The foetus can sustain severe damage before the development of toxoplasma-specific antibodies. However, if this infection is contracted before pregnancy, it poses no threat to the foetus since the maternal antibodies protect it. People with weakened immune systems, especially those with HIV and AIDS, are also at significant risk for toxoplasmosis. Hence, it is vital to differentiate between the acute and chronic stages of the disease to reduce its effects and to chart out an adequate treatment plan. Since it is difficult to isolate the parasite, the diagnosis is usually made via serological methods. The toxoplasma avidity IgG test is the standard blood test that checks for toxoplasma-specific antibodies in the blood. The testing requires only a blood sample. For pregnant women, the doctor will take a sample of the amniotic fluid and the foetus’s blood. The doctor then studies the samples to determine if the infection has been transmitted to the foetus. The avidity IgG test is primarily responsible for measuring the antibody binding force, which differs depending on the time of the infection. The antibody binding force is low in the early stage after the primary infection occurs A high avidity IgG test signals that the infection likely occurred around 4 months ago IgG antibodies are notorious for appearing a few weeks after the toxoplasmosis infection and may remain in the body forever. But the blood test can detect these antibodies almost instantly. Apollo 24|7 offers a comprehensive toxoplasma avidity IgG test to determine the presence of the infection in the body. Although the toxoplasmosis infection is mainly asymptomatic, the few visible symptoms associated with it are similar to that of flu. Some of these include: Body aches Swollen lymph nodes Headache Fever Fatigue These symptoms may differ in individuals with weakened immune systems. They may encounter the following symptoms: Lung problems akin to tuberculosis  Poor coordination Seizures Retinal inflammation leading to blurred vision Confusion Constant headache Children might also contract a toxoplasmosis infection from their mothers and may display symptoms like severe eye infections and yellowing of the skin.    Medically reviewed by Dr. Ravikiran Barigala, Infectious disease, Apollo Hospitals Jubilee Hills, Hyderabad.