Scientists publishing a new, global study have called for the World Health Organisation (WHO) to recognise the dangers posed by a common parasite that infects cats
Scientists have warned that a common pet parasite infecting potentially up to a third of the world’s population could leave billions of people susceptable to serious health consequences.
A collaborative multi-university study has called for a global push to recognise toxoplasma gondii as a clear and present danger to millions of people, despite having once been understood not to have significant health impacts. The parasite, which is also known as toxo and carried by cats, has been dubbed the “leading intraocular infection worldwide” and is known to infect billions of people, although the vast majority remain symptom-free – especially if they’re healthy.
But the researchers have discovered that the toxoplasmosis-causing parasites can also cause a retina-damaging eye infection, and have called for it to be recognised as a neglected tropical disease (NTD).
Professor Justine Smith, the author of the study, which published in the journal PLOS Neglected Tropical Diseases, said toxoplasmosis is “a leading eye infection and a major cause of vision loss worldwide”. But, she added, it “receives limited attention in global health agendas”.
Most people who experience toxoplasmosis won’t have symptoms, but people with compromised immune systems can experience flu-like effects.
Symptoms can mimic those caused by the virus or glandular fever, including a high fever, body aches and muscle pain, and tend to go away on their own. But in some cases, the parasite can live dormant in people’s bodies, completely undetected, and activate later on to cause eye infections in people- immune compromised or not.
Ocular toxoplasmosis causes eye pain and redness, blurred or reduced vision, and dark spots known as “floaters” that drift across the vision. In severe cases, it can cause retinal inflammation and permanent blindness.
The PLOS paper was led by Associate Professor João Furtado, of the University of São Paulo and Professor Smith from Flinders University in Adelaide, Australia. The pair brought together experts from the Americas, Europe, Africa, and Asia. Professor Smith said the eye-damaging effects of toxoplasmosis deserve more attention, as they tend to receive “limited attention”.
She said: “Toxoplasmosis is a leading eye infection and a major cause of vision loss worldwide, yet it receives limited attention in global health agendas. With WHO’s recognition, we can make substantial progress in prevention and management of this infection.”
Professor Furtado, the study’s second author, said additional recognition and appropriate attention would allow public health specialists to reduce the potentially massive impact toxoplasmosis eye infections can have.
He said: “Toxoplasmosis is often seen as inevitable, but it has well-characterised transmission pathways and can be prevented and controlled. These impacts could be reduced through practical public health measures such as improved food safety, clean water, sanitation and better access to antenatal care.”
People are usually infected with toxoplasma gondii after eating undercooked meat, contaminated water or produce, and exposure to cat faeces. Cats themselves are usually infected by eating or drinking from a contaminated source.
