Listeria and pregnancy

Listeriosis is a rare but serious disease caused by the bacteria Listeria monocytogenes and is produced typically by consuming certain foods contaminated with listeria. While it is probably common for people to eat foods contaminated with a small amount of the bacteria, only some people are at risk of becoming sick. Pregnant women are at an increased risk due to their reduced immunity during pregnancy. 

What are the symptoms of Listeriosis?

Symptoms are mild for pregnant women however, it can be harmful to your unborn or newborn baby.  Symptoms may include:

• High temperature
• Flu-like symptoms 
• Abdominal pain
• Vomiting and/or diarrhea
• Headaches
• Muscle aches and pains

Symptoms can appear 3 to 70 days after eating contaminated food. Listeriosis can be treated so important to seek immediate medical attention to avoid any complications. Without treatment, listeriosis can cause preterm birth or miscarriage. It is important that pregnant women who have symptoms of listeriosis seek medical attention immediately.

What foods should I avoid? 

The risk of developing listeriosis may be reduced by avoiding the consumption of high-risk foods. High risk foods include:

• Raw seafood such as sashimi, smoked fish, smoked mussels and oysters 
• Pre-prepared and refrigerated salads (e.g. coleslaw, pre-packaged salad and fruit salad)
• Ready-to-eat deli meat products such as ham, turkey, salami and patѐ
• Unpasteurized milk or products containing unpasteurized milk
• Soft cheeses including brie, camembert and ricotta
• Soft serve ice cream 
• Rock melon
• Raw mushrooms

How do I to reduce my risk of Listeria?

The risk of listeriosis can also be reduced by practicing safe food handling. Safe food handling practices include: 

• Washing hands before and during food preparation 
• Using separate chopping boards, bowls and utensils for raw and cooked foods
• Separating raw and cooked foods to avoid cross-contamination 
• Storing cold foods in the fridge (below 5°C)
• Thoroughly washing raw fruits and vegetables with clean water before consumption 
• Defrosting frozen food in the fridge or microwave, avoid defrosting foods on the bench 
• Thoroughly cooking raw foods
• Avoid eating food past its use-by or best before date

For more information on healthy eating during pregnancy click here

References 

1. Lamont RF, Sobel J, Mazaki-Tovi S, Kusanovic JP, Vaisbuch E, Kim SK, et al. Listeriosis in human pregnancy: a systematic review. J Perinat Med. 2011 Apr 25;39(3):227-36. 
2. Department of Health. Listeria Fact Sheet [Internet]. Canberra: Australian Government; [updated 2020 Apr 09]. Available from: https://www1.health.gov.au/internet/main/publishing.nsf/Content/ohp-listeria-fs.htm#:~:text=Listeria%20in%20Australia,outbreak%2C%20however%20outbreaks%20can%20occur.
3. Janakiraman V. Listeriosis in pregnancy: diagnosis, treatment, and prevention. Rev Obstet Gynecol. 2008;1(4):179-85. 
4. Madjunkov M, Chaudhry S, Ito S. Listeriosis during pregnancy. Arch Gynecol Obstet. 2017 Aug 1;296(2):143–52.
5. Department of Health and Human Services. Listeria – the facts [Internet]. 2010 [cited 2020 Jul 27]. Victoria: State Government of Victoria; Available from: 2010;https://www2.health.vic.gov.au/about/publications/factsheets/Listeria—the-facts.

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