Infectious diseases Biomarker
Collection Type: Blood
Related System: Infectious diseases
Toxoplasma Ab IgG measures IgG-class antibodies directed against Toxoplasma gondii, the parasite that causes toxoplasmosis. IgG appears weeks after infection and typically persists for life, indicating past exposure or established immunity; it does not by itself prove active recent infection. The test is used when exposure, congenital infection, ocular disease, unexplained lymphadenopathy, or systemic illness is suspected, and routinely in prenatal screening and in immunocompromised patients. Seroprevalence increases with age and varies by geography, diet, and socioeconomic factors; women of childbearing age and immunosuppressed people have special clinical implications for positive results.
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Q: What does a positive toxoplasma IgG antibody mean?
A: A positive Toxoplasma gondii IgG antibody indicates past exposure and usually immunity; IgG appears weeks after infection and often persists lifelong. It does not by itself mean active infection (that’s suggested by IgM or rising titres). In pregnancy, positive IgG with negative IgM generally implies prior infection and low fetal risk, but follow-up tests and clinical advice may be needed.
Q: What if toxoplasma IgG is negative?
A: A negative Toxoplasma IgG means you likely have no past exposure and lack immunity, so you're susceptible to new infection. If recent exposure is suspected, or if pregnant or immunocompromised, clinicians usually check IgM and repeat tests after 2 to 3 weeks to detect seroconversion. Continue prevention measures (avoid undercooked meat, unwashed produce, and cat litter) and consult your healthcare provider for guidance and follow-up.
Q: What are the symptoms of toxoplasmosis IgG?
A: A positive toxoplasma IgG usually indicates past infection and most people have no symptoms. When illness occurs it’s typically mild low fever, fatigue, muscle aches and swollen lymph nodes. In immunocompromised people or with reactivation, more serious signs can appear: headache, confusion, seizures, fever, respiratory problems and focal neurologic deficits. In pregnancy, acute infection (IgM), not IgG, carries fetal risk.
Q: What does it mean when your IgG antibody is positive?
A: A positive IgG antibody test indicates your immune system has produced IgG antibodies against a specific pathogen or vaccine, reflecting past infection or immunization. It usually appears weeks after exposure and can suggest some level of protection, but doesn’t guarantee immunity or its duration. Results must be interpreted with the specific test, timing, and clinical context in mind—discuss findings with your healthcare provider.
Q: How to avoid toxoplasmosis during pregnancy?
A: During pregnancy, avoid toxoplasmosis by not eating raw or undercooked meat and unpasteurized dairy; wash fruits, vegetables, and kitchen surfaces; freeze meat before cooking; wear gloves when gardening or handling soil and wash hands afterwards; avoid changing cat litter (or have someone else clean it daily) and, if unavoidable, wear gloves and wash hands thoroughly; avoid contact with stray cats and don’t feed them raw meat.
Q: How many cat owners have toxoplasmosis?
A: An estimated roughly one-third of people worldwide have been infected with Toxoplasma gondii at some point, though regional rates vary widely. In many developed countries prevalence is lower (often around 10–30% depending on age and testing). Most cat owners are not infected; infection commonly arises from undercooked meat and soil exposure rather than cat ownership alone.