A common parasite that is spread by undercooked pork and sometimes our cats can have more insidious health consequences than previously thought. New research suggests a link between infection with Toxoplasma gondii and an increased risk of brain cancer. At this stage, however, scientists are still unsure whether there is a direct cause-and-effect link, and the overall risk of brain cancer is still very low.
T. gondii is familiar for his mind-altering tricks on rodents, one of their natural intermediate hosts. In these animals, the unicellular parasites cause them to become reckless in danger, causing them to no longer avoid the smell of cat urine. The toboggants – and their parasites – are then more likely to be caught by a cat, enabling the parasites to reach their primary cat host and reach full maturity. They then breed and create a new generation of eggs that are depleted by the cat in the area and begin the gruesome life cycle anew. Humans are an unfortunate bystander in all these things and become infected through close contact with cat poop or by eating meat (usually pork) that is infected with T. gondii last.
Acute T. gondii infections in humans, it can be serious for those with a weakened immune system or for newborns who contracted it while in the womb. In most people, however, an acute infection does not cause any symptoms, while some mild, flu-like symptoms may develop for several weeks.
Historically, these acute symptoms have been considered to be the extent of the damage T. gondii for us can cause. But more recently, scientists have found that a intriguing connection between the parasite and subtle neurological effects in humans, aided by the fact that cysts can survive for decades in the body, including the brain. Chronies T. gondii infections have been linked to an increased risk of schizophrenia, decreased cognition and behavioral changes such as more risks and aggression. This new study, published in the International Journal of Cancer, indicates that certain types of brain cancer may need to be added to the list above.
G / O Media can get a commission
The researchers looked at data from research projects that track people’s health over time, including a lengthy study on cancer prevention conducted by the American Cancer Society. They specifically focused on people who later found gliomas, the most common form of brain cancer. As part of their initial investigation, the volunteers gave blood samples that were tested on antibodies against various germs T. gondii.
When the researchers compared people who eventually developed gliomas in these studies with similar people who did not, they found that the glioma group had a greater chance of T. gondii antibodies. In general, the presence of T. gondii is associated with more than a double increased risk of glioma. In people with the highest levels of one specific type of antibody against T. gondii, the associated risk was more than three times greater. About 350 people with glioma, including people older than 70 and younger than 40, were studied, with similar risks in both age groups.
Other studies have found a similar link between T. gondii and brain cancer. However, according to the authors, this is the first evidence of prospective research, that is, when people are observed before they develop the condition being studied. This is important because scientists can know thing A clearly – in this case, T. gondii infection – happens before thing B – brain cancer. This alone can not prove it T. gondii helps cause brain cancer, but it’s proof that the connection is more likely.
‘The findings suggest that individuals with a higher exposure to the T. gondii parasite is more likely to develop glioma, ”said study author Anna Coghill, a researcher at the Moffitt Cancer Center, in a study. statement released by the American Cancer Society. “However, it should be noted that the absolute risk of being diagnosed with a glioma is still low, and these findings need to be repeated in a larger and more diverse group of individuals.”
There are about 24,000 new cases of brain cancer estimated to occur annually in the U.S., accounting for about 1% of all cancers. Meanwhile, it is estimated that 11% of Americans wear older than six years T. gondii, so more than 30 million people. This means that the chance of brain cancer due to chronic, even if this connection is real T. gondii infection is very low at individual level. Similarly, not everyone who develops glioma will have T. gondii, and there are people with T. gondii who would have got brain cancer, even if the infection had never occurred – cancer risk is intricate like this.
Yet this is the latest research that suggests that hidden infections in the body and brain can affect our health long after they have first arrived.