Food Safety for Moms-to-Be: Medical Professionals - Foodborne Pathogens

Food Safety for Moms-To-Be

Important information to help you educate women about food safety during pregnancy.

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Top 14 Foodborne Pathogens

Foodborne pathogens can seriously affect anyone, but for pregnant women and their babies, certain pathogens can be particularly harmful - even fatal. 

As you know:

  1. During pregnancy, the immune system is weakened, which makes it hard for the mother's body to fight off harmful foodborne bacteria, such as Listeria.
  2. Harmful foodborne bacteria can cross the placenta and infect the developing fetus.
  3. The fetus doesn't have a fully developed immune system to fight off harmful foodborne bacteria.

The Top 14 Foodborne Pathogens chart gives detailed information about the most common foodborne pathogens. It highlights pregnancy-risk pathogens and helpful "must-knows" specific to pregnant women and their children.

For more information on how foodborne illness can be prevented, see Lifelong Food Safety.

Campylobacter jejuniA bacterium that's the most common bacterial cause of diarrhea in the U.S. Must-Know: Children under age 1 have the highest rate of Campylobacter infections. Unborn babies and infants are more susceptible on first exposure to this bacterium. In addition, there's a low threshold for seeking medical care for infants.Raw milk, untreated water, raw and undercooked meat, poultry, or shellfishDiarrhea (sometimes bloody), stomach cramps, fever, muscle pain, headache, and nausea.Generally 2 to 5 days after eating contaminated food2 to 10 days
Clostridium botulinumA bacterium that can be found in moist, low-acid food. It produces a toxin that causes botulism, a disease that causes muscle paralysis. Must-Know: Don't feed a baby honey - at least for the first year. Honey can contain Clostridium botulinum spores. Infant botulism is caused by consuming these spores, which then grow in the intestines and release toxin.Home-canned and prepared foods, vacuum-packed and tightly wrapped food, meat products, seafood, and herbal cooking oilsDry mouth, double vision followed by nausea, vomiting, and diarrhea. Later, constipation, weakness, muscle paralysis, and breathing problems may develop. Botulism can be fatal. It's important to get immediate medical help.12 to 72 hours after eating contaminated food (in infants 3 to 30 days)Recovery can take between 1 week to a full year.
Clostridium perfringensA bacterium that produces heat-stable spores, which can grow in foods that are undercooked or left out at room temperature.Meat and meat productsAbdominal pain, diarrhea, and sometimes nausea and vomiting.8 to 16 hours after eating contaminated foodUsually 1 day or less
Pathogenic Escherichia
coli (E. coli)
A group of bacteria that can produce a variety of deadly toxins.Meat (undercooked or raw hamburger), uncooked produce, raw milk, unpasteurized juice, and contaminated waterSevere stomach cramps, bloody diarrhea, and nausea. It can also manifest as non-bloody diarrhea or be symptomless. Must-Know: E.coli 0157:H7 can cause permanent kidney damage which can lead to death in young children.Usually 3 to 4 days after ingestion, but may occur from 1 to 10 days after eating contaminated food.5 to 10 days
Listeria monocytogenesA bacterium that can grow slowly at refrigerator temperatures. Must-Know: Listeria can cause serious illness or death in pregnant women, fetuses, and newborns.Refrigerated, ready-to-eat foods (meat, poultry, seafood, and dairy - unpasteurized milk and milk products or foods made with unpasteurized milk)Fever, headache, fatigue, Muscle aches, nausea, vomiting, diarrhea, meningitis, and miscarriages.9 to 48 hours after ingestion, but may occur up to 6 weeks after eating contaminated food.Variable
Norovirus (Norwalk-like Virus)A virus that's becoming a health threat. It may account for a large percent of non-bacterial foodborne illnesses.Raw oysters, shellfish, cole slaw, salads, baked goods, frosting, contaminated water, and ice. It can also spread via person-to-person.Diarrhea, nausea, vomiting, stomach cramps, headache, and fever.24 to 48 hours after ingestion, but can appear as early as 12 hours after exposure.1 to 3 days
Salmonella EnteritidisA bacterium that can infect the ovaries of healthy-appearing hens and internally infect eggs before the eggs are laid.Raw and undercooked eggs, raw meat, poultry, seafood, raw milk, dairy products, and produceDiarrhea, fever, vomiting, headache, nausea, and stomach cramps Must-Know: Symptoms can be more severe in people in at-risk groups, such as pregnant women.12 to 72 hours after eating contaminated food4 to 7 days
Salmonella TyphimuriumSome strains of this bacterium, such as DT104, are resistant to several antibiotics.Raw meat, poultry, seafood, raw milk, dairy products, and produceDiarrhea, fever, vomiting, headache, nausea, and stomach cramps Must-Know: Symptoms can be more severe in people in the at-risk groups, such as pregnant women.12 to 72 hours after eating contaminated food4 to 7 days
ShigellaA bacterium that's easily passed from person-to-person via food, as a result of poor hygiene, especially poor handwashing. Only humans carry this bacterium.Salads, milk and dairy products, raw oysters, ground beef, poultry, and unclean waterDiarrhea, fever, stomach cramps, vomiting, and bloody stools1 to 2 days after eating contaminated food5 to 7 days
Staphylococcus aureusThis bacterium is carried on the skin and in the nasal passages of humans. It's transferred to food by a person, as a result of poor hygiene, especially poor handwashing. When it grows in food, it makes a toxin that causes illness.Dairy products, salads, cream-filled pastries and other desserts, high-protein foods (cooked ham, raw meat and poultry), and humans (skin, infected cuts, pimples, noses, and throats)Nausea, stomach cramps, vomiting, and diarrheaUsually rapid - within 1 to 6 hours after eating contaminated food24 to 48 hours
Vibrio choleraeA bacterium that occurs naturally in estuarine environments (where fresh water from rivers mix with salt water from oceans). It causes cholera, a disease that can cause death if untreated.Raw and undercooked seafood or other contaminated food and water.Often absent or mild. Some people develop severe diarrhea, vomiting, and leg cramps. Loss of body fluids can lead to dehydration and shock. Without treatment, death can occur within hours.6 hours to 5 days after eating contaminated food3 to 7 days
Vibrio parahaemolyticusA bacterium that lives in saltwater and causes gastrointestinal illness in people.Raw or undercooked fish and shellfishDiarrhea, stomach cramps, nausea, vomiting, headache, fever, and chills4 to 96 hours after eating contaminated food2 to 5 days
Vibrio vulnificusA bacterium that lives in warm seawater. It can cause infection in people who eat contaminated seafood or have an open wound exposed to seawater.Raw fish and shellfish, especially raw oystersDiarrhea, stomach pain, nausea, vomiting, fever, and sudden chills. Some victims develop sores on their legs that resemble blisters.1 to 7 days after eating contaminated food or exposure to organism2 to 8 days
Yersinia enterocoliticaA bacterium that causes yersiniosis, a disease characterized by diarrhea and/or vomiting.Raw meat and seafood, dairy products, produce, and untreated waterFever, diarrhea, vomiting, and stomach pain

Must-Know: Symptoms may be severe for children.

1 to 2 days after eating contaminated food1 to 3 weeks

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Page Last Updated: 11/08/2017
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