How Listeria Spread: Sprouts and Melons

Key points

  • People who eat food contaminated with Listeria bacteria can get a harmful infection.
  • Sprouts and melons can be contaminated with Listeria.
  • Sprouts grow in warm, humid conditions, which are ideal conditions for Listeria to grow.
  • Listeria also can grow in melons, which are low in acid and often refrigerated for a long time.
A cantaloupe that has been cut open.

Sprouts

Sprouts need warm and humid conditions to grow. These conditions are also ideal for the growth of Listeria and other harmful germs. Germs can grow on the inside and outside of sprouts, so washing them does not remove all germs.

Home-grown sprouts can also have germs because they need the same conditions to grow.

Multistate outbreak:

Melons

Melons are more likely than many other fruits to be contaminated with Listeria.

This is because they have low acidity and can be kept in the refrigerator for a long time. Both these conditions support the growth of Listeria.

Multistate outbreak:

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