A common parasite spreads through undercooked pork, and occasionally our cats can have more insidious health effects than previously suspected. New research suggests a link between infection with Toxoplasma gondii and an increased risk of brain cancer. At this point, however, scientists are still unsure whether there is a direct cause and effect relationship, and the overall risk of brain cancer is still very low.
T. gondii It’s known for his mind-altering tricks in rodents, one of its natural intermediate hosts. In these animals, unicellular parasites induce them to become reckless in the face of danger, causing them to no longer avoid the smell of cat urine. Rodents – and their parasites – are then more likely to be swallowed by a feline, allowing the parasites to reach their primary feline host and reach full adulthood. They then breed and create a new generation of eggs that are shit by the cat in the environment, restarting the horrible life cycle. Humans are an unhappy spectator in all of this, being infected by close contact with cat poop or by eating meat (usually pork) contaminated with T. gondii cysts.
Acute T. gondii infections in people it can be serious for those with weakened immune systems or for newborns who have contracted during the uterus. In most people, however, an acute infection does not cause symptoms, while some may develop mild, flu-like symptoms for several weeks.
Historically, these acute symptoms were considered to be the extent of damage that T. gondii can cause for us. But more recently, scientists have discovered a intriguing connection between the parasite and the subtle neurological effects on people, aided by the fact that cysts can survive quietly in the body, including the brain, for decades. Chronicle T. gondii infections have been associated with an increased risk of schizophrenia, decreased cognition and behavioral changes, such as increased risk and aggression. This new study, Published at the International Journal of Cancer, indicates that certain types of brain cancer may need to be added to the list above.
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The researchers analyzed data from research projects that track people’s health over time, including a long-term study on cancer prevention conducted by the American Cancer Society. They focused specifically on people who later discovered they had gliomas, the most common form of brain cancer. As part of the initial examination, volunteers gave blood samples that were tested for antibodies to various germs, including T. gondii.
When researchers compared people who developed gliomas in these studies to similar people who did not, they found that the glioma group had a greater chance of having T. gondii antibodies. In general, the presence of T. gondii was associated with a more than twice as high risk of glioma. In people with the highest levels of a specific type of antibody for T. gondii, the associated risk was more than three times higher. About 350 people with glioma, including people over 70 and under 40, were studied, with similar associated risks seen in both age groups.
Other studies have found a similar link between T. gondii and brain cancer. However, according to the authors, it is the first evidence of what is known as prospective research, which is when people are observed before they develop the condition being studied. This is important, because scientists can clearly know which thing A – in this case, T. gondii infection – happens before thing B – brain cancer. This alone cannot prove that T. gondii helps to cause brain cancer, but it is evidence that makes the connection more likely.
“The results suggest that individuals with greater exposure to T. gondii The parasite is more likely to develop glioma, ”said study author Anna Coghill, a researcher at the Moffitt Cancer Center, in a declaration launched by the American Cancer Society. “However, it should be noted that the absolute risk of being diagnosed with a glioma remains low and these findings need to be replicated in a larger and more diverse group of individuals.”
There are about 24,000 new cases of brain cancer estimated which occurs annually in the USA, accounting for about 1% of all cancers. Meanwhile, it is believed that 11% of Americans over six years carries T. gondii, then more than 30 million people. This means that, even if this connection is real, the chances of developing brain cancer as a result of chronic illness T. gondii infection are very low on an individual level. Likewise, not everyone who develops glioma will have T. gondii, and there are people with T. gondii who would have contracted brain cancer even if the infection had never happened – the risk of cancer is complicated Like that.
Still, this is the latest research suggesting that infections hidden in the body and brain can influence our health long after they arrive.