Toxoplasmosis: the parasite found in meat that can seriously damage your eyesight

A widely prevalent parasite found across the globe, Toxoplasma gondii, is causing concern among medical researchers. It causes toxoplasmosis, an infection that often produces no symptoms in healthy individuals. However, specialists warn that in certain cases, the disease can severely affect the eyes and lead to vision loss.

According to estimates cited by researchers, approximately one third of the world's population is infected with this parasite. Ocular toxoplasmosis is considered the most common intraocular infection worldwide and one of the leading infection-related causes of vision loss.

A disease not taken seriously enough

Although it can cause serious damage to the eyes, toxoplasmosis does not receive the international attention it deserves, specialists argue. Dr Justine Smith, an ophthalmologist and vision researcher at Flinders University in Australia, believes the disease should be taken more seriously in global health policy.

"Toxoplasmosis is a major cause of ocular infection and a significant cause of vision loss worldwide, yet it receives limited attention on global health agendas," said Dr Justine Smith.

In her view, stronger recognition of the disease by the World Health Organisation could improve the way it is prevented and treated. "Through WHO recognition, we can make substantial progress in preventing and managing this infection," she noted.

How the infection is transmitted

The primary route of transmission is the consumption of undercooked meat contaminated with the parasite. Another means of infection is the accidental ingestion of eggs shed in cat faeces — for example, when cleaning a litter tray or through contact with a contaminated environment.

Transmission from mother to foetus via the placenta during pregnancy is also a significant route of infection. In such cases, the infection can result in pregnancy loss or severe congenital conditions.

"Toxoplasmosis is often considered inevitable, but it has well-known transmission routes and can be prevented and controlled," explained Dr João Furtado of the University of São Paulo, Brazil.

A widespread but understudied disease

Researchers say that toxoplasmosis meets the criteria to be classified as a neglected tropical disease: it is concentrated in impoverished areas, prevalent in tropical and subtropical regions, preventable and controllable, yet chronically underfunded and under-researched.

The disease is more common in South America and in resource-limited regions, and the funds allocated to its research are far lower compared to other similar diseases.

The absence of a vaccine — a sign of how the disease is underestimated

There is neither a vaccine nor a standard treatment protocol for toxoplasmosis, which, according to researchers, reflects how greatly its global impact is underestimated. It is estimated that approximately 190,000 children are born with congenital toxoplasmosis each year.

The most serious consequences occur in vulnerable communities where access to healthcare is limited and sanitary conditions are poor. In these areas, prevention becomes all the more important.

Measures that could reduce the risks

Specialists believe that the impact of the disease could be reduced through simple public health measures: improved food safety, access to clean water, better sanitation, and expanded antenatal care.

"These effects could be reduced through practical public health measures, such as improved food safety, clean water, sanitation, and better access to antenatal care," explained Dr João Furtado.

Researchers warn that toxoplasmosis should not be regarded as a minor infection simply because, in many cases, it produces no visible symptoms. When it affects the eyes or occurs during pregnancy, the disease can have serious consequences.