Nobody likes it when their pet is accused of spreading diseases. I remember hearing news a while ago that a dog parasite, Toxocara canis, could be transmitted through contamination from dog feces – and the campaign to use pooper scooters was born.
Now the US Centers for Disease Control and Prevention has published worrying statistics that around 40 million people in the US have a parasite called Toxoplasma gondii in their brain.
This parasite can spread to humans from their domestic cats, reports scientist and writer Dan Robitzski.
The reason we should all be careful is that toxoplasmosis, the disease caused by the Toxoplasma parasite, appears to run parallel to an increased risk of glioma from brain tumor, according to the American Cancer Society study.
The study looked at two groups of people – from a study by the American Cancer Society and the Norwegian Cancer Registry’s Janus Serum Bank – to compare the prevalence of glioma and T-Gondii antibodies in blood samples from patients.
Analysis showed a clear connection between the two, but it’s only a connection. It is not proof.
The study does not establish a cause and effect between the parasite and the development of brain tumor.
So if you are a cat owner don’t worry, this study certainly doesn’t suggest that owning a cat increases your risk of cancer.
Rather, the likelihood is that the two factors (toxoplasmosis and brain tumor) are somehow related, or that one factor somehow makes people more susceptible to the other.
While the general trend in the data leans strongly in the direction of a parasite-brain tumor correlation, the data also suggest that a small number of toxoplasmosis patients appeared to have a lower risk of developing glioma, or no association at all.
Another point to consider is that people with toxoplasmosis may be more likely to be exposed to other things that can cause cancer.
So the correlation is by no means certain.
The numbers are small, but the study paves the way for further research. We also need a lot more research to determine the relationship between cats and brain cancer.
“Our results provide the first prospective evidence for a link between T-Gondii infection and glioma risk,” the new publication states.
“Further studies with larger case numbers are needed to confirm a possible etiological role for T gondii
in glioma. ”