A study has revealed how up to 30 percent of Americans could be infected with a dangerous parasite.

According to researchers at the University of California, Riverside, over 100 million Americans could be infected with a bug that impacts how the brain communicates.

The toxin is called Toxoplasma gondii - also known as T. gondii, and can enter the body by eating undercooked meat or through exposure to cat feces.

The new study has revealed that between 10 to 30 percent of people in the US could be infected without even realising.

In a paper published in PLoS Pathogens, scientists explained how the parasite can interfere with brain cells by infecting a number of neurons.

The neurons impacted by the toxin were found to release fewer extracellular vesicles which are crucial in exchanging information.

“We found this disruption in EV signaling can interfere with how neurons and glial cells, especially astrocytes, maintain a healthy brain environment,” said Emma H. Wilson, who led the research.

“Even a handful of infected neurons can shift the brain’s neurochemical balance. This suggests that communication between neurons and supporting glial cells is not only critical, but also vulnerable to hijacking by parasites.”

Using a combination of mice and human cells, Wilson explained the research revealed how the disruption of neurons can result in heightened glutamate levels, leading to seizures and other neurological issues.

While the parasite can lie dormant for years, it can activate and cause severe illness.

“The parasite may play a larger role in neurological and behavioral conditions than we previously thought,” she said.

“Our brains have built-in defenses that may recognize and respond to neurons infected by Toxoplasma gondii.

“If we can learn how to support or enhance that process, we may be able to better protect people, especially the most vulnerable.”

Although there are only tests to find out if a person has ever been infected with the toxin - and not one to establish whether it is still present - Wilson hopes the research can help identify therapies and vaccines.

“There’s no need to avoid someone who is infected; most people live their entire lives without symptoms,” she said.

“Pregnant individuals should be cautious as the parasite can cause serious birth defects if contracted for the first time during pregnancy. The most effective prevention is proper food handling and hygiene. Cook meat thoroughly, wash vegetables, and always wash your hands after handling cat litter, especially from young cats, which are more likely to shed the parasite.”

Souces: Unilad