The European Food Safety Authority has published an open-access report with a description of parasites not routinely controlled in food: Cryptosporidium spp., Toxoplasma gondii and Echinococcus spp.
Each of these parasites can be transmitted by ingesting contaminated foods – often fresh produce not cooked before consumption. Individual methods of identification and recording currently exist for each parasite with no standard protocol to monitor the safety of food. Creating food safety protocols for these parasites is complex. In the case of Echinococcus spp, there can be a delay of many years between infection and symptoms. The existence of lifecycles that include wildlife also makes evaluation complex. This report offers some useful guidance, however.
Cryptosporidium can be present in many hosts and survive wet environments but the transmission of its oocysts is inactivated by pasteurization. There is an ISO standard method for detecting Cryptosporidium oocysts although it is only valid for some fresh products, including berry fruits.
Toxoplasma can be transmitted via the ingestion of raw or undercooked meat from infected animals. Freezing meat before consumption and limiting cats’ access to farms can help to reduce the risk of transmission.
The main source of Echinococcus is infected dogs and foxes and the importance of food-borne transmission is unclear. Important preventive procedures include the control of stray dogs, meat inspections, sheep vaccination and the routine deworming of dogs.
To reduce the risk posed by these parasites, simple measures such as hand-washing, washing fresh produce prior to consumption and avoiding ready-to eat products are important. More research is certainly needed and the link between farm and table must always be considered when taking measures to reduce food-borne diseases.
EFSA Panel on Biological Hazards (BIOHAZ). 25 October 2018. Public health risks associated with food-borne parasites. doi: 10.2903/j.efsa.2018.5495