The bacterium causes listeriosis, a bacterial infection that can cause severe illness, including severe sepsis, meningitis, or encephalitis, which can result in lifelong harm and even death. Symptoms include fever and muscle aches, gastrointestinal problems, headaches, confusion and convulsions.

In addition to the 150 people known to be infected, the Spanish Ministry of Health has confirmed that it is investigating an additional 523 suspected cases.

The outbreak is believed to have originated from a processed meat product manufactured in Seville that has since been withdrawn from sale. Although it is hoped that this will reduce future cases, a spokesperson from the World Health Organization said that it is likely that there will be more cases in the coming days and weeks due to the long incubation period of the disease.

Acting Health Minister Maria Luisa Carcedo commented on how the outbreak occurred: “Obviously there was a failure to follow the established procedures. Now we need to carry out the inspections and investigations to figure out exactly where this failure took place.”

The authorities have warned tourists that the infection can be contracted by eating contaminated food or coming into contacted with infected humans or animals. The elderly, pregnant women, newborns and people with weakened immune systems are particularly at risk.

Tourists are advised to refrain from consuming the affected product, ‘Mecha’ branded meat, and if they have consumed the product and develop symptoms, they should seek medical advice. Additional precautions that can be taken include ensuring all food is cooked thoroughly and following food and water hygiene advice.