Why do we love cats so much?

 

Why do we love cats so much? Could there be a scientific explanation and if there is, is it dangerous? One of our speculations is Toxoplasmosis caused by a parasite called toxoplasma gondii. Like all parasites, toxoplasma gondii can’t live on its own. It needs a host to live. Without a host, a parasite can’t live and multiply. Organisms that are infected with this parasite are usually asymptomatic. When they do show symptoms, they are mild and flu-like. However, recent studies have shown that toxoplasma is more likely to affect your physiological behavior than physical symptoms.

Before we explain the effects of toxoplasmosis on humans, let’s take a look into its life cycle. Its life cycle includes two hosts, a definitive host which toxoplasma will reproduce sexually and form eggs called oocysts and an intermediate host which it will reproduce by making clones of itself called tissue cysts. The intermediate host includes all kinds of mammals like rodents, cows, pigs, birds, and even humans. The definitive host is none other than cats. When oocysts are produced in the cat’s intestines, they will eventually be shed in the cat’s feces. A single infected cat can shed up to a million oocysts in one day. 

After this stage is when intermediate hosts come to play. Sporulated oocysts in cat’s feces are consumed by mammals most likely rodents. Once a rodent consumes a sporulated oocysts, it will form tissue cysts in the rodent’s body. If the rodent is eaten by a cat, the tissue cysts become active in the cat’s intestines and release new oocysts. Hence, making a never-ending loop.

Rodents aren’t the only animals that end up with toxoplasma, humans can also come in contact with them. Humans can accidentally consume oocysts in contaminated water, unwashed produce, and of course cat feces. Consuming does not necessarily mean eating cat feces. They are consumed by inhaling the air surrounding cat’s feces when cat owners clean out litter boxes. This is behind the strict recommendation that pregnant women did not change litter boxes. Toxoplasmosis can result in birth defects and even miscarriage in pregnant women.

We can also come in contact with toxoplasma from eating undercooked meat from other mammals that could possibly ingest oocysts.

Now that we know how toxoplasma infects us, what are the effects on humans? Studies have found a connection between toxoplasma with schizophrenia, OCD, and bipolar disorder. It also slows reactions and decreases concentration. 

Once an intermediate host is infected with sporulated oocysts which results in tissue cysts, it will remain in the intermediate host’s body for life. But like all living creatures, this parasite’s main goal is to reproduce more and more of itself to continue its kind. It does that by increasing dopamine. When dopamine is released, it creates the feeling of pleasure. The result is a fatal attraction. For this reason, is toxoplasma the reason so many of us are attracted to cats? 

By Felicia M/XIIA1/11