The recent outbreak of listeria caused by Jensen Farms/Frontera cantaloupes was the most recent reminder that Listeria poses the greatest risk to certain groups of people.  The most deadly foodborne illness outbreak in U.S. history sickened 146 and has now killed 31 people.   According to the CDC, the average age of vicitms was 77 years.  The average age of those who died was even higher – demonstrating the increased risk that those of advanced age face.

Reuters reported today on addtional medical research from France that demonstrated, among other things, that Leukemia patients are at the greatest risk for listeria infection.   The study involved roughly  2,000 cases of listeriosis in France between 2001 and 2008.  Among the findings:

  • More than 400 of the 2,000 people who developed listeriosis died.
  • None of the cases involved an outbreak.
  • About one in six of the listeriosis cases in France affected pregnant women.
  • Among the remaining cases, 65 percent of the people involved had an underlying health condition, and 41 percent were undergoing treatment that suppressed their immune systems.
  • People with chronic lymphocytic leukemia were at the greatest risk of developing listeriosis — more than 1,000 times higher than the general French population.