[Two children in the Netherlands with a Corynebacterium diphtheriaeinfection]

Infections with Corynebacterium diphtheriae were virtually absent among the Dutch population due to vaccination, while in the first half of the 20th century, it was a significant cause of child mortality. However, due to imported infections resulting from migration from countries with low vaccination coverage, infections with Corynebacterium diphtheriae are resurging. Concurrently, the vaccination rates among Dutch children are decreasing, elevating the risk of outbreaks. Severe symptoms are caused by exotoxins from the C. diphtheriae, infections with non-toxigenic strains can occur, which vaccination does not protect against. The bacteria itself is rarely invasive; only the toxin spreads. Non-toxin-producing strains manifest locally with milder symptoms but can become invasive, causing bacteraemia and endocarditis. As infections with non-toxigenic strains are not notifiable, little is known about their epidemiology. Moreover, specific culture media are required for bacterial cultivation, potentially leading to missed diagnoses.