Research needed on toxoplasmosis food safety threat

05-Jun-2012 - Last updated on 18-Jul-2024 at 13:33 GMT

Pregnant women are advised to avoid eating undercooked meat such as pig meat, which is known to be at risk of toxoplasma infection

More research is needed to determine how big a role food plays in the transfer of the parasitic disease toxoplasmosis to humans in the UK, according to scientists.

Following an assessment of the risk profile of toxoplasma in the food chain conducted by the Advisory Committee on the Microbiological Safety of Food (ACMSF), it is to submit recommendations to the Food Standards Agency (FSA), which it advises.

While accurate figures are not available, a draft report produced by ACMSF estimates that 350,000 people become infected with toxoplasma each year in the UK, of which 10–20% show symptoms of the disease.

Toxoplasmosis is a notifiable disease in Scotland but neither a notifiable nor reportable disease in the rest of the UK.

Although many of those infected may not show any symptoms, for individuals that are immune-compromised – including unborn babies – the symptoms are more severe and potentially life-threatening.

Pregnant women

Pregnant women are at higher risk and are advised to avoid eating undercooked meat such as pig meat, which is known to be at risk of toxoplasma infection. (For more information, click here).

From data obtained in the US and the Netherlands, the report suggested “the costs of the relatively small proportion of cases with severe disease make toxoplasmosis one of the most costly of gastro-intestinal infections”.

It added: “This would justify further work to assess the importance of the foodborne route of infection, to identify the most important risks and appropriate risk management measures, and to refine the burden of disease assessment.”

As long ago as 2007, Dr Pascal Boireau, a director at the AFSSA, the French equivalent of the FSA, told Food Manufacture that toxoplasma in the UK meat chain – particularly from outdoor reared pork – was likely to be much higher than generally recognised.

Toxoplasma contamination

Boireau claimed that 80% of toxoplasma contamination occurred from meat and that the threat from livestock was growing with the trend towards outdoor reared animals. (For more, click here).

The ACMSF report suggested that toxoplasma infection was most common in sheep, pigs and wild game. It said: “There is a very small amount of data on meat contamination in the UK but (other than a recent serological survey of sheep) virtually none on the presence of the parasite in farm animals reared in the UK.”

It added: “Further data on seroprevalence[the number in a population which test positive for a specific disease based on blood serum] in farm animals would be useful in monitoring the effectiveness of control measures in animal husbandry and testing of a larger range of meat samples would be useful in identifying the main source of risk.”

ACMSF called for further studies.