100m infected with parasite that 'silently' eats away at the brain... subtle sign YOU have it

• READ MORE: Urgent warning over deadly infection spread by dodgy cheese

Alarming findings show that potentially more than 100 million Americans have been infected with a parasite that silently eats away at the brain.

A new study by scientists at the University of California , Riverside, estimates that 10 to 30 percent of people in the US are infected with Toxoplasma gondii (T. gondii), often without knowing it.

Previous studies have linked it to mind-altering behavior, such as risk-taking, depression and even schizophrenia.

The parasite, which can lie dormant in the brain for decades, is typically contracted through undercooked meat or exposure to cat feces.

Most people infected with Toxoplasma gondii experience no symptoms. When symptoms do occur, they often resemble those of the flu , such as fever, swollen lymph nodes, muscle aches, and fatigue, as well as confusion, poor coordination and muscle weakness.

Because it typically mimics more benign conditions, the infection is often overlooked, but can be diagnosed via blood tests that look for antibodies.

The milder symptoms usually subside within a few weeks with the help of anti-parasitic medicines or antibiotics, but in individuals with weakened immune systems, pregnant women, and infants, toxoplasmosis can cause more severe complications such as seizures and difficulty breathing.

Now, based on their research, the scientists believe they have potentially found a way to detect T. gondii and treat it.

The team discovered infected neurons in the brain release fewer extracellular vesicles (EVs) — particles that play a role in communication between cells.

Lead researcher Emma Wilson, professor of biomedical sciences, said: 'Our research opens the door to using EVs as biomarkers, which can be isolated from blood.'

Current diagnostic tools can only confirm if someone has been exposed to T. gondii by identifying antibodies, proteins produced by the body's immune system to fight foreign invaders like bacteria and viruses.

However, tests cannot detect if the parasite is still active in the brain or how it might be impacting brain function.

Wilson and her team are now conducting further research to better understand how the parasite operates in a bid to develop new therapies to clear the parasite or even vaccines in the future to protect against it.

In humans, T. gondii can lead to toxoplasmosis, which causes flu-like symptoms that can go largely unrecognized.

Pregnant women who ingest the parasite in early pregnancy can suffer a miscarriage or stillbirth, according to studies.

Most infections go away without treatment but medication is available for those who are more at risk of serious complications.

The researchers behind the most recent study say that there is 'no need to avoid someone who is infected [and] most people live their entire lives without symptoms'.

But there are signs it could be linked to brain damage.

Studies suggest patients infected with T. gondii were almost 50 percent more likely to have been diagnosed with schizophrenia than those without, for example.

Offering advice in terms of avoiding infection, researchers behind the new paper added: '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.'

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