Your cat may be like your child. But, in fact, you may not be able to have your own biological child because of the cat. That's because of a potentially dangerous parasite protozoan, Toxoplasma gondii, that enters your body when you handle the feces of infected cats or ingest raw or undercooked meat of an intermediary host like rabbit or sheep, or when you eat/drink aliments or water contaminated with parasite eggs from cat feces, which are the only species lodging the parasite during the sexual stage of its life cycle.
20% to 80% of human populations worldwide are infected with Toxoplasma (over 60 million Americans are infected). Usually, initial exposure causes only mild flu-like symptoms. After that, the parasite passes
down into an inactive cyst stage that stays resident in muscles and other tissues. Latent toxoplasmosis is asymptomatic, but is usually a life-long infection, and its presence is proved by the presence of anti-Toxoplasma antibodies in the blood.
The parasite can trigger severe health problems in pregnant women and individuals with lowered immune reaction, like HIV positive patients or organ transplant recipients. If a woman gets infected with Toxoplasma for the first time while she is pregnant, the parasite can travel across the placenta and cause miscarriage and birth defects. Testing for previous exposure to the parasite is standard in many maternity clinics. A 2006 research showed that toxoplasmosis skews towards the increase in male births, but it did not establish cause and effect.
Now, a new Australian study published in ACS' Nano Letters comes with a method employing a new type of gold nanoparticle for killing the Toxoplasma parasites.
As gold does not interact with human cell structures, the "golden bullet" technology could be a safer, more effective way to destroy the parasites, than conventional drug therapy.
The team led by Michael Cortie attached antibodies to the parasite onto gold nanorods that are shut on by laser-light. Toxoplasma-infected animal cells were isolated from cell cultures and put in contact with the "golden bullets".
Subsequently, the cells were exposed to laser-light, which raised the temperature of the "bullets" and killed the parasites, in a proportion of about 83 %. The next step is changing the technique, so that it could be used for killing the parasite in human patients.