How to Kill Toxoplasma gondii? Transmission Routes and Treatment for Infection in Pregnant Women

People preparing for pregnancy all know how terrifying it is to be infected with Toxoplasma gondii, because both dogs and cats are hosts of Toxoplasma gondii, so how do you kill Toxoplasma gondii? What are the transmission routes? What should pregnant women do if infected?

What exactly is Toxoplasma gondii?

Toxoplasma gondii is also called the three-corpse worm, and it is an intracellular parasite. It parasitizes inside cells, travels with the bloodstream, reaches every part of the body, and damages the brain, heart, and fundus of the eye, causing a person's immunity to decline and leading to various diseases. It is an obligate intracellular parasite, in the subclass Coccidia, order Eucoccidiida, family Eimeriidae, genus Toxoplasma. In a sense, it is almost the most successful single-celled animal on Earth. However, compared with its much more famous relative——the malaria parasite, this worm came into human view only relatively recently. In 1908, two French scholars discovered it in the gundi (Ctenodactylus gundi) in North Africa.

How does Toxoplasma gondii cause infection?

Cats are the only definitive host of Toxoplasma gondii. In other words, Toxoplasma gondii produces eggs only inside cats.

Cats may become infected after eating infected wild game or raw meat.

Three to 10 days after infection, the eggs begin to be shed in the feces, lasting about 10-14 days. The eggs become infectious after 1-5 days in the environment. Generally speaking, by the time a cat shows symptoms, it has already passed the period of shedding eggs.

Other animals (including dogs) and humans are intermediate hosts and become infected by eating infectious eggs, but after infection they do not produce eggs in the body. Therefore, dogs are not a transmission route for Toxoplasma gondii, unless infected raw dog meat is handled or eaten.

In the United States, 22.5% of people over 12 years old have been infected with Toxoplasma gondii. Globally, in some areas 95% of people have been infected with Toxoplasma gondii. The vast majority of people have no symptoms or only flu-like symptoms.

How do people become infected with Toxoplasma gondii?

Pregnant women or people with weakened immune systems are more likely to become infected.

Because cats shed eggs for only a brief few days, the likelihood of transmitting it to people is relatively small.

If indoor cats have no opportunity to come into contact with infected soil and raw meat, the infection rate is very small.

The chance of infection through petting a cat is also extremely small.

More infections occur through eating infected raw meat, unwashed vegetables and fruits, or unpasteurized dairy products.

What symptoms does Toxoplasma gondii infection cause?

According to different studies, the Toxoplasma gondii infection rate in our country's population is at a relatively low level worldwide, about 5%-20%. Even so, the “toxoplasmosis patients” around us are still a fairly large group. At the same time, we do not seem to feel this. This is because Toxoplasma gondii infection rarely causes serious consequences. For people with good immune function, first contact with Toxoplasma gondii at most causes mild flu-like symptoms, such as fatigue, muscle aches, low fever, or swollen lymph nodes, and these symptoms disappear before long. Pregnant women generally have no symptoms when infected. One-third to one-half of infected pregnant women will transmit it to the fetus. Most infected infants have no symptoms at birth, but afterward may develop vision, hearing, or intellectual impairments.

How do you kill Toxoplasma gondii?

If infected pregnant women are treated in time, the incidence of congenital Toxoplasma gondii infection in infants can be reduced from 60% to 23%; if untreated, about 50% can infect the fetus through the placenta.

Drug treatment currently generally uses spiramycin. This drug belongs to the macrolide class, has low toxicity, and is relatively safe for use in pregnant women. When used in large doses, gastrointestinal reactions such as nausea, vomiting, and diarrhea may occur. For usage and dosage, please follow a doctor's advice, and do not use it indiscriminately on your own.

Timely and appropriate treatment can bring toxoplasmosis under control or cure it. Traditional anti-Toxoplasma drugs are sulfadiazine and pyrimethamine, and now spiramycin, clindamycin, azithromycin, and other drugs can also be used. Treatment of toxoplasmosis must be carried out under the guidance of an experienced doctor, to determine suitable drug combinations, dosage, and course of treatment, and to prevent the occurrence of drug side effects.

How can Toxoplasma gondii be avoided?

The U.S. Centers for Disease Control and Prevention (CDC) points out that pregnant women do not need to avoid cats. Here are some suggestions:

For pregnant women:

Do not eat raw meat.

Do not eat unpasteurized dairy products.

Do not eat unwashed vegetables and fruits.

Do not drink water from the environment unless it has been boiled.

After handling raw meat, wash your hands thoroughly with soap and clean the countertop.

Wear gloves when touching plants, trees, and soil.

Wash your hands before eating.

For cats:

Do not feed raw meat or unpasteurized milk to cats.

It is best to keep cats completely indoors, avoiding contact with infected soil, animals, and raw meat.

Scoop the litter box every day, and frequently scald and wash the litter box with boiling water. (Because the eggs in the feces need 1-5 days to become infectious.)

Pregnant women should avoid cleaning the litter box; this is the man's job.

Avoid stray cats, and do not get a new cat during pregnancy.

Control the number of intermediate hosts, such as mice.