Big 6 Foodborne Illnesses

Big 6 Foodborne Illnesses: How to Prevent Them?

There are numerous diseases that cause serious consequences for human health. Stay for more information on the big 6 foodborne illnesses

January 1, 2022

There are approximately 40 kinds of viruses, fungi, bacteria, and parasites on the list that the FDA has officially published. They are all dangerous pathogens and seriously affect human health. Many of them are highly contagious and have the potential to create pandemics worldwide. However, the FDA also identifies exactly 6 types of diseases that are dangerous, contagious, and have the most severe symptoms. So what are those big 6 foodborne illnesses? In this guide, Servsafe-Prep will show you more useful information.

Big 6 Foodborne Illnesses
Big 6 Foodborne Illnesses

1. Hepatitis A


Hepatitis A is a disease caused by the hepatitis A virus. This is a disease that is transmitted from person to person by the fecal-oral route due to contaminated water, and contaminated food but not thoroughly cooked. Hepatitis A virus is one of a number of hepatitis viruses that damage liver epithelial cells and impair liver function.

Unlike hepatitis B, the hepatitis A virus does not cause chronic hepatitis, which is inflammation of the liver that doesn’t last more than 6 months and is very rarely fatal. A small percentage of deaths in the setting of acute liver failure. Hepatitis A can be completely cured in 2-4 weeks. Currently, there is an effective and safe vaccine against hepatitis A.

Symptoms of Hepatitis A

Some people can be infected with the hepatitis A virus without showing any symptoms. Children often have mild symptoms, while symptoms in adolescents and adults are often more severe. Common symptoms include:

  • Fatigue: This is the first manifestation that appears when you have hepatitis A, harmful toxins are retained in the body, making the whole body feel tired and uncomfortable.
  • Digestive disorders: When infected with the hepatitis A virus, signs of gastrointestinal disease appear such as loss of appetite, nausea, vomiting, mild abdominal pain in the right rib area, diarrhea, constipation…
  • Mild fever: When the body is inflamed in any part, the number of white blood cells is mobilized to increase to fight invading agents, causing fever.
  • Skin manifestations: Toxins retained in the liver will be emitted through itchy skin and pimples. Another sign is elevated levels of albumin in the liver, which causes the skin to appear light or dark yellow, depending on the severity of the disease.
  • Yellow urine: This is a common sign that appears in most hepatitis B, C, alcoholic hepatitis …
  • Muscle and joint pain: This symptom is uncommon, about 10% of people with hepatitis A have this symptom, indicating that your disease has progressed to the chronic stage.

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How is hepatitis A transmitted?

In people with hepatitis A, the virus is found most often in feces, and also in saliva and urine. The main routes of transmission of the hepatitis A virus include:

  • Eating food prepared by someone with hepatitis A who did not wash their hands thoroughly after using the toilet
  • Drinking water from a polluted water source
  • Eating shellfish and snails living in polluted water
  • Frequent contact with people with hepatitis A

In general, hepatitis A is not transmitted by blood because there is very little virus in the blood. The fecal-oral route is the main route of transmission of the disease. Eating contaminated food or food, drinking contaminated water, swimming in infected ponds or swimming pools, sharing food, and sharing personal items such as towels, towels, etc. with an infected person can transmit hepatitis A.

Prevention of Hepatitis A

Currently, there is no specific treatment for hepatitis A. Instead, the main treatment regimen is still to ensure adequate nutrition and avoid permanent liver damage. Hepatitis A can be prevented by ensuring food hygiene and personal hygiene. As follows:

  • Ensure food safety
  • An adequate supply of safe drinking water
  • Proper wastewater treatment
  • Practice personal hygiene regularly

Several injectable inactivated hepatitis A vaccines are available worldwide. There is no licensed vaccine for children under 1 year of age. Manufacturers recommend 2 doses of the vaccine to ensure longer-lasting protection about 5 to 8 years after vaccination.

2. E. Coli


E. Coli (short for Escherichia coli) is a bacterium belonging to the microbial system of the human and animal body. They live mainly in the intestinal system and have the largest number in the body’s microbiome.

There are many types of E. Coli, normally they are not harmful but make an important contribution to helping the body digest foods that the stomach cannot digest. But when the body appears to be unable to create the right conditions for the entry and growth of certain groups of E. Coli, they have the ability to produce potent toxins and become one of the causes. the main cause of diarrhea, abdominal pain, and fever. The most common pathogenic E. Coli is E. Coli O157:H7.

Symptoms of E. Coli

Food poisoning caused by E. Coli is usually transmitted mainly through the gastrointestinal tract, from person to person or from animal to human, through food, drinking water, dirty hands, personal utensils, and utensils. Eating utensils are contaminated with bacteria. Common symptoms of common E. Coli infection include:

  • Mild or severe diarrhea that occurs suddenly with loose stools, sometimes with blood in the stools
  • Cramping or dull abdominal pain
  • Nausea, vomiting, loss of appetite
  • In severe cases, symptoms such as dehydration, blood in the urine, pale skin may appear, and bruises may appear even though there was no previous impact,…

Causes of E. Coli

There are many causes of E. Coli infections such as:

  • Contaminated food sources: the most common cause. Food can become contaminated due to improper handling or storage, such as:
  • Do not wash or wash your hands uncleanly before cooking or before eating.
  • Using dirty dishes or utensils, food damaged by improper storage (inappropriate temperature and humidity).
  • Eating undercooked food, eating raw seafood without washing it thoroughly,…
  • Slaughtering or meat processing of infected poultry, etc.
  • Contaminated water: drinking contaminated water or swimming in a contaminated lake.
  • Person-to-person transmission: E. Coli bacteria are very easily spread to others when hands are not thoroughly washed after cleaning or touching others or sharing items with an infected person.
  • Animals: People who come into contact with animals, especially cows, goats, and sheep are also at risk of contracting bacteria that live in animals.

Prevention of E. Coli

  1. Coli bacteria are ubiquitous in the environment, so the prevention of bacterial infections is very important. There are many methods to prevent diarrhea caused by E. Coli such as:
  • Use safe food: use only fresh foods. It is necessary to soak and wash thoroughly with clean water raw fruits and vegetables. Fruit should be peeled before eating. Do not use frozen foods that have been defrosted and refrozen.
  • Food that has just been cooked should be eaten immediately, ensuring the taste of the dish and avoiding contamination from the environment.
  • Store cooked foods carefully and properly. Cooked foods are reused after 5 hours and should be reheated thoroughly. Reusable foods should not be used for children.
  • Clean surfaces of food preparation utensils. Cooked food can become contaminated with pathogens from contact with raw food or with dirty surfaces (such as sharing knives and cutting boards for food preparation). Dishes need to be boiled in boiling water and wiped dry with a clean towel.
  • Wash hands and utensils before preparing food and after each interruption to other activities. If your hand has open or infected wounds, let’s clean and seal the wound thoroughly before preparing food.
  • The food needs to be covered in sealed containers, glass cabinets, table cages, covered with clean towels, etc. to prevent insects from entering.
  • Keep water sources clean, and avoid contamination of human and animal feces.

3. Nontyphoidal Salmonella


Nontyphoidal Salmonella, also known as typhoid bacteria, includes S. typhi and S. paratyphi A, B, and C all strains are capable of causing typhoid. Nontyphoidal Salmonella enters the body’s digestive system, and after death, it releases endotoxins. The endotoxins of salmonella bacteria cause very bad effects in the intestine, the endotoxins will damage the intestinal lining (irritation of the intestines causing abdominal pain, bleeding, or possibly perforation).

Nontyphoidal Salmonella infection is a bacterial infection in the stomach and intestines. Most patients with mild infections clear up on their own in 4 to 7 days without treatment.

Symptoms of Nontyphoidal Salmonella

Most people infected with Salmonella have the following signs and symptoms 12 to 72 hours after exposure to the bacteria:

  • Diarrhea: Loose, viscous, yellow-brown stools, very pungent, about 5-6 times/day
  • Continuous high fever (39 or 400C)
  • Abdominal pain and bloating in the right iliac fossa.
  • Neurotoxicity due to Salmonella bacterial toxins (headache, insomnia, nightmares, tinnitus, slurred speech).
  • In severe cases, people infected with Salmonella have symptoms of shaking hands to catch dragonflies or lying motionless, apathetic, lethargic, lethargic, delirium, and coma (uncommon).

In rare cases, Salmonella infection can be fatal if the person is not treated promptly and correctly. However, there are some people who are infected with Salmonella, but because the body already has antibodies, the number of bacteria is small and the virulence of the bacteria is weak, so they may have digestive disorders for a few days and then go away on their own. A very small number of them become carriers of the bacteria, which can last for many months.

Prevention of Nontyphoidal Salmonella

To prevent typhoid caused by Salmonella bacteria, people should follow these guidelines:

  • Wash your hands with soap and warm water after using the toilet, changing a baby’s diaper or touching animals, and eating or preparing food.
  • Thoroughly cook all foods (beef, pork, chicken, duck…)
  • Wash cutting boards and counters used to prepare meat or poultry immediately after use to avoid cross-contamination with other foods.
  • Health authorities need to have a plan to periodically check the health and check food safety and hygiene at hotels, restaurants, food-service facilities, and distribution places (markets, supermarkets…).

4. Norovirus


Norovirus is a highly contagious stomach and intestinal virus. It is easily transmitted through direct or indirect contact with an infected person. It can spread rapidly in areas such as hospitals, schools, and daycare centers. Most people can get a norovirus infection. This is a common disease of the stomach and intestines. Norovirus can also be a source of food poisoning, as you can get it from eating contaminated food. 

Symptoms of Norovirus infection

After onset, symptoms persist for 24 to 72 hours. It is estimated that in some cases, about 30% of the virus causes no symptoms, which is common in children. However, if symptoms persist or there is blood in the stool, the person should see a doctor soon. Besides, frequent and profuse diarrhea can lead to dehydration, which is a medical emergency. Dehydration can be recognized by the following signs:

  • The feeling of dry mouth and throat
  • Decreased urine output or dark urine
  • Drowsy and tired
  • Headache
  • Confusion or indifference to the external environment
  • Fast heartbeat

How is the Norovirus virus transmitted?

Norovirus leaves the body through the feces and vomit of an infected person. Norovirus spreads easily from person to person. People infected with norovirus are most contagious from the moment they first feel sick until at least 3 days after their symptoms disappear. People can get the virus from:

  • Eating food or drinking liquids contaminated with norovirus. Sick food handlers can contaminate raw or undercooked food (including farm produce and shellfish).
  • Touching surfaces or objects contaminated with norovirus and then putting your hands in your mouth or sharing food or utensils with the infected person.
  • Inhaling the virus released from the vomit of an infected person.
  • Close contact with someone who has the virus.

Prevention of Norovirus

There is currently no vaccine to prevent this disease. However, following these steps can help keep the risk of infection to a minimum:

  • Wash your hands after using the bathroom, changing diapers, or caring for someone who is sick. When washing your hands, it’s best to wash them with soap and water for at least 20 seconds.
  • When caring for an infected person, wear gloves and use a plastic bag to clean up dirt or diapers. A disinfectant or chlorine solution can then be used to clean contaminated surfaces.
  • Do not eat food or drink prepared by someone infected with the virus
  • Wash your hands before preparing food and when eating
  • Wash all food before eating or before preparing it
  • Do not eat raw or undercooked seafood
  • Do not swim in public swimming pools when you have diarrhea

People with symptoms should stay at home. This is especially important if the patient works in the food service, health care, or education industry. Children who are sick are also not allowed to go to school, daycare, or participate in community activities.

5. Shigella


Shigella are Gram-negative, shellless, hairless, motile, and non-spore-forming bacilli. This bacterium can cause gastroenteritis and bacillary dysentery in humans. There are four distinct groups of Shigella: Shigella dysenteriae, Shigella flexneri, Shigella boydii, and Shigella sonnei. In an infected person, Shigella bacteria are excreted in the feces.

Symptoms of Shigella

Some people have true shigella infections but have no symptoms. However, the germs (bacteria) will still be present in the stool and they can still pass the disease on to others.

However, most people infected with shigella usually show symptoms. Symptoms tend to appear within 1-7 days of exposure to the bacteria (eg, drinking contaminated or contaminated water, eating contaminated food). The time before symptoms appear is often called the “incubation period”. Symptoms are usually diarrhea (which will often contain blood and mucus – dysentery), abdominal cramps, and a high temperature (fever). Symptoms tend to last for about 5-7 days.

Symptoms can be severe in some people, especially the young and the elderly. Diarrhea can get worse and lead to a lack of body fluids (dehydration). You should consult your doctor promptly if you suspect you are becoming dehydrated. Mild dehydration is common and is usually easily reversed by drinking plenty of fluids. Severe dehydration can be fatal if not treated quickly because your body’s organs need a certain amount of fluid to function.

Prevention of Shigella infection

If you have shigella, the following is recommended to prevent spreading the infection to others:

  • Wash hands thoroughly after using the toilet with soap, and dry hands properly after washing. 
  • Do not share personal items with someone who is infected with Shigella
  • People with Shigella should not cook for others
  • Wash the patient’s clothes and blankets separately
  • Every day, the toilet should be cleaned with hot water and detergent, especially the handle, shower, doorknob,…
  • Persons infected with Shigella should stay away from work and school until 48 hours after the last episode of diarrhea or vomiting, and avoid contact with other people during this time.
  • People infected with Shigella, if they work in food processing, should immediately stop working and notify their manager until the disease is completely treated, ensuring no spread.
  • When traveling to areas with poor sanitation, avoid drinking tap water, eating ice cream, eggs, salads, undercooked meat, peeled fruit, etc. because Shigella bacteria are usually transmitted through drinking contaminated water or eating contaminated food.

If treated early, patients infected with Shigella bacteria can recover quickly within 1-2 weeks. However, with severe forms of the disease, if not detected early and treated promptly, the disease can cause death due to complications. Therefore, when there are warning signs of gastroenteritis or dysentery caused by Shigella bacilli, the family should soon take the patient to the doctor for active and effective treatment.

6. Salmonella typhi


Salmonella typhi or typhoid bacillus is the causative agent of typhoid. This is a gram-negative, motile, ciliated bacterium that does not produce spores in the external environment. Typhoid is a blood-borne infection caused by the bacteria Salmonella typhi. Most people in the United States get typhoid while visiting another country from eating or drinking contaminated food or drink. In developing countries, typhoid often causes epidemics.

Symptoms of Salmonella typhi infection

Typhoid fever has different clinical manifestations depending on the patient. Typically, patients will experience the following symptoms:

  • Whole-body fatigue, headache, loss of appetite
  • Fever: Appears suddenly, gradually increasing the temperature in the following days. Fever is higher in the evening, sometimes accompanied by chills. Body temperature sometimes reaches the threshold of 41 degrees Celsius. High fever causes headaches, and worsening general condition.
  • Digestive disorders: Infection with Salmonella typhi bacteria can cause constipation or diarrhea in patients.
  • Erythema: Scarlet fever in typhoid fever can be found in many places in the body such as the chest, back, and extremities. The rash may have a maculopapular, initially measles-like rash.

Typhoid goes through many different disease stages. The first week from the onset of symptoms is a good time for treatment. Skipping this stage, the incidence of complications will be higher, such as meningitis, intestinal perforation, osteomyelitis, endocarditis, …

Prevention of Salmonella typhi infection

Typhoid is a preventable and limited disease if preventive measures are well implemented in the community. People need to coordinate with health workers to adhere to the following:

  • Disseminating health knowledge to those around in many forms such as television, newspapers, leaflets, or live discussions and activities.
  • Maintain the hygiene of the living environment, especially the water source for domestic use and irrigation.
  • Properly handle waste sources such as feces, urine, and garbage.
  • Cook food, do not eat raw foods of unknown origin and quality.
  • Boil drinking water, and give up the habit of drinking water directly from rivers, streams, ponds, and lakes.
  • Vaccination: Typhoid has a vaccine to prevent disease with good immunity. This is an active disease prevention measure that should be encouraged and implemented, helping to significantly reduce morbidity and mortality from disease in the community.

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In conclusion, understanding and preventing foodborne illnesses is crucial for maintaining our health and well-being. By practicing good hygiene, such as proper handwashing and sanitation, along with safe food handling and storage techniques, we can significantly reduce the risk of contamination. Additionally, ensuring that food is cooked thoroughly and avoiding high-risk foods can further protect us from these illnesses. By being knowledgeable and vigilant, we can enjoy a safe and healthy eating experience.

In addition to the definition of the big 6 foodborne illnesses, the above article has also provided information about the causes, symptoms, and prevention of these illnesses. Hope you guys have more useful knowledge to protect the health of yourself and your family.

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