A common parasite spread by cats may increase your risk of developing brain cancer, scientists have warned.
The parasite, called toxoplasma gondii (T. gondii), is usually spread to humans through contact with cat faeces, or by eating undercooked meat.
Most people who become infected with the parasite are not aware of it, and will not experience any major symptoms.
However, new research indicates that T. gondii could increase your risk of developing glioma, an aggressive type of brain cancer.
The parasite, called toxoplasma gondii (T. gondii), is usually spread to humans through contact with cat faeces, or can be acquired from undercooked meat
WHAT IS TOXOPLASMOSIS?
Toxoplasmosis is caused by a common brain parasite Toxoplasma gondii.
It is usually contracted via cat faeces, but can also be caught from uncooked infected meat, especially lamb or pork.
The condition is often symptomless but can cause miscarriage or stillbirth in pregnant women and can also be dangerous for people with weakened immune systems.
Up to half the world’s population is thought to be infected with toxoplasmosis, but without showing any symptoms.
The infection can be detected using a blood test.
It does not usually require treatment but medication can be used in more vulnerable patients.
In the study, published in Cancer Epidemiology, researchers from the American Cancer Society in Atlanta examined the link between T. gondii antibodies and glioma – a type of tumour that occurs in the brain and spinal cord.
Glioma is relatively rare, with an estimated 300,000 incident cases in 2018.
However, it is a highly fatal cancer, with the majority (80 per cent) of malignant tumours being gliomas.
The study analysis revealed that people who have glioma are more likely to have antibodies to T. gondii (indicating that they have had a previous infection) than a similar group that was cancer-free.
According to the researchers, this suggests that exposure to the parasite could increase your risk of aggressive brain tumours.
Dr Anna Coghill, assistant professor at the Moffitt Cancer Center and co-author of the study, said: ‘The findings do suggest that individuals with higher exposure to the T. gondii parasite are more likely to go on to develop glioma.
‘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.’
Toxoplasma gondii is a single-celled parasite that can infect most warm-blooded species of animals — including humans — and cause the disease toxoplasmosis.
It is only known to reproduce sexually in cats.
Toxoplasma gondii is a single-celled parasite that can infect most warm-blooded species of animals — including humans — and cause the disease toxoplasmosis
Humans can be infected with the T. gondii parasite in a number of ways.
One of the most common ways people become infected is by consuming undercooked or contaminated meat.
However, the parasite can also be passed on to humans through contact with cat faeces.
The Centres for Disease Control and Prevention explained: ‘This might happen by cleaning a cat’s litter box when the cat has shed Toxoplasma in its faeces, touching or ingesting anything that has come into contact with cat faeces that contain Toxoplasma, or accidentally ingesting contaminated soil.’
Toxoplasmosis is caused by a common brain parasite Toxoplasma gondii, which is usually passed to humans via cats
Most people who become infected with the parasite will experience no symptoms, or basic flu-like symptoms.
However, in some cases, and particularly in people with weakened immune systems, the parasite can cause damage to the brain, eyes or other organs.
Meanwhile, a bizarre recent study also found that the parasite can be linked to increased sexual arousal from fear and danger.
The research, published in the journal Evolutionary Psychology, was based on 36,564 people in Slovakia and the Czech Republic, some of who were infected with toxoplasmosis and some of which were parasite-free.
‘Infected subjects are more often aroused by their own fear, danger, and sexual submission,’ according to the study carried out by researchers from Charles University in Prague.
The study says that people with toxoplasmosis have a ‘higher attraction to bondage, violence and, in men, to masochism and raping’.
WHAT IS A GLIOMA?
Gliomas are brain tumours that start in the glial cells – the cells that surround neurones, helping to support and protect the nerve cells.
Around 2,200 cases of glioma are diagnosed every year in the UK, statistics show.
And the tumours affect two-to-three in every 100,000 adults annually in the US.
The most common type of glioma is an astrocytoma, which develops from cells called astrocytes.
Unspecified gliomas occur when a doctor cannot tell the exact tumour grade or where it started.
Low-grade tumours, which are slow growing, may not need immediate treatment and are monitored via ‘watchful waiting’.
Around half of low-grade tumours need operating on within two-to-three years of monitoring.
Surgery may be carried out to remove as much of a low-grade tumour as possible, which is known as debulking.
Radiotherapy may then be carried out if a lot of the tumour remains.
Chemo may be recommended instead of radiotherapy if a patient has a specific genetic mutation.
High-grade gliomas require surgery, which may be followed by radiotherapy.
This does not cure the tumour but aims to control it.
Source: Cancer Research UK