Émile Pierre-Marie van Ermengem (1851–1932) was a Belgian bacteriologist who, in 1895, isolated Clostridium botulinum, the bacterium that causes botulism, from a piece of ham that had poisoned thirty-four people.^[1]

Van Ermengem was born in Leuven on 15 August 1851. After studying in Berlin he became a professor at the University of Ghent. He became a corresponding member of the Académie royale de médecine de Belgique in 1887 and a full member in 1902, serving as secretary 1919–1932.^[2]

He died in Ghent on 29 September 1932.^[2] His sons were the writer Franz Hellens and the art critic François Maret.