In 2019, 12 sea otters, a specialty from California, USA, drowned one after the other. Sea otters are marine mammals, so drowning in such large numbers is very rare. Scientists began to investigate with doubts, and as a result, they found that it was caused by a parasitic infection called Toxoplasma gondii or Toxoplasma gondii.
In California, USA, there was an incident where many sea otters infected with feline parasites diedㅣSource: Getty Image Bank
Professor Karen Shapiro from the University of California, Davis, USA, who led the investigation at the time, said, “The parasite caused problems with the sea otter’s brain function, so it seems that the sea otter forgot how to swim and drown .” He said. Toxoplasmosis infects most warm-blooded animals, including sea otters, but is actually better known as a millet parasite. This is because it can only grow and reproduce as an adult in the cat’s body. Other warm-blooded animals, such as sea otters, are only intermediate hosts through which they pass to reach their offspring. The problem is that humans can also become intermediate hosts for this parasite.
Cat parasites use humans as intermediate hosts
According to data released by the Ministry of Health and Welfare in 2012, it was estimated that 10-30% of the world’s population was infected with Toxoplasma gondii, and in particular, the infection rate was expected to reach 70-80% in France, where a culture of loving cats has developed. In the case of Korea, according to the results of a survey published by the Society of Parasitology in 2012, the domestic Toxoplasma infection rate reached 25%. There are two main routes for people to become infected with Toxoplasma gondii. Cats infected with Toxoplasma gondii excrete faeces containing millions of eggs of the parasite every day for several weeks immediately after infection. If you eat raw meat or contaminated vegetables such as chickens, cows, or pigs that have come into contact with this faeces, or if you come into direct contact with faeces, you will get infect you with Toxoplasma gondii.
In most cases, there are no symptoms
An infection with toxoplasmosis is called toxoplasmosis. Fortunately, even if a healthy person is infected with Toxoplasma gondii, the immune system fights the larvae and wins, so most cases do not recognize the infection because there is no symptoms. Even if symptoms do appear, they are considered minor as they are at the level of a mild cold. However, the case of a person with a weak immune system is different. When the immune system fails to overcome the parasite and invades the brain, symptoms such as △ headache △convulsions △consciousness disorder △difficulty breathing are accompanied. If a patient with a serious disease such as cancer becomes infected, it can cause serious infectious diseases such as pneumonia and encephalitis. If the eye is infected with a parasite, Toxoplasma retinitis can lead to eye pain, blurred vision, sensitivity to light and, in the worst case scenario, blindness.
Infection during pregnancy is also dangerous. If a pregnant woman is infected with Toxoplasma gondii, there is a high risk that the fetus will be born with congenital toxoplasmosis. Babies with congenital toxoplasmosis can suffer from △blindness △encephalitis △epilepsy △intellectual disability △developmental failure. There are also examples of abortion. Therefore, prenatal toxoplasmosis testing is essential.
A parasite that controls its host and even causes mental illness?
There is also a study that toxoplasmosis infection causes mental illness. Toxoplasma gondii is a parasite with host manipulation properties by infiltrating the host’s brain, and is known to cause abnormal behavior in rodents used as an intermediate host. For example, mice infected with Toxoplasma gondii lose their fear of cats, become less alert and more active. Academics speculate that this is because the parasite controls the rat and increases the chance of it being eaten by the cat.
According to a similar principle, there is also a study that Toxoplasma gondii affects the human brain and causes mental illness. Researchers at the Academic Medical Center in the Netherlands analyzed the results of more than 50 studies examining the link between Toxoplasma gondii and schizophrenia, and found that people infected with Toxoplasma gondii had more than twice the risk of schizophrenia with those who had not turned. out to be a place In addition, according to a study analysis published by Johns Hopkins University researchers in the United States in 2015, around 50% of those who had a cat as a child were 42% more likely to be diagnosed with schizophrenia or other mental disorder than those who had a cat as a child. it seemed high.
The treatment for toxoplasmosis is surprisingly simple. A blood test is done to determine if there is an infection, then antibiotics are taken. So, should we avoid pets to prevent toxoplasmosis? That’s not it. A cat infected with Toxoplasma gondii transmits the parasite through faeces for only two weeks in a cat’s life. However, when touching the soil outside, make sure you wear gloves, wash vegetables and fruit clean, and cook meat well before eating. If you have a cat, you should clean the toilet often, use gloves when removing faeces, and wash your hands thoroughly afterwards. In addition, it is important to see your vet regularly.