Invasive Listeriosis in Europe – A Case Review

Listeria monocytogenes bacilli are a known cause of non-invasive gastrointestinal listeriosis with diarrhea, less frequently they cause invasive infections: meningitis and encephalitis, bacteremia and its complications: endocarditis, intraocular inflammation of the eye and others. The risk of human infection is mainly associated with consuming food contaminated with these bacteria. According to the European Food Safety Authority (EFSA), infections with L. monocytogenes etiology caused the highest hospitalizations and deaths among zoonotic diseases reported in 2022. A report by the European Center for Disease Prevention and Control (ECDC) reported 0.44 cases of listeriosis per 100,000 population in 2021, with the highest incidence rate for people over 64 years old at 1.7.

The study aimed to review and describe cases of invasive listeriosis diagnosed in adult patients in Europe between 2010 and 2023. Fifty-two cases of the disease were included, of which 19 were meningitis, 13 showed bacteremia, nine were associated with endocarditis and 10 with intraocular inflammation. One case had a clinical form of hepatitis. Only seven cases of L. monocytogenes infection were related to consuming contaminated food. Eleven cases ended in the death of patients.

Invasive listeriosis is a difficult-to-treat infection with a significant mortality rate. It requires decisive action by monitoring the prevalence and extent of food contamination with these microorganisms and preventing epidemic outbreaks. Research on listeriosis should focus on improving the clinical treatment of severe cases of infection and studying the complex mechanisms of their pathogenesis.