Salmonella is a type of bacteria that causes a foodborne illness known as salmonellosis. It is the most common type of food poisoning which may affect over 1 million people in the U.S. and is responsible for thousands of hospitalizations and hundreds of deaths each year.
Most people who are affected by Salmonella are unaware that they have food poisoning but in severe cases, it can be deadly. Symptoms of Salmonella usually begin within 8 to 72 hours but most people recover in a few days.
In other cases, Salmonella food poisoning may cause severe diarrhea which may cause dehydration and require hospitalization. If the infection spreads beyond the intestines, it may become life-threatening.
What Types of Food Causes Salmonellosis?
Foodborne illness caused by Salmonella is known as salmonellosis. It is caused by Salmonella bacteria which normally live in the intestines of humans and animals. Human infections of Salmonella are generally caused by undercooked foods, contaminated water or foods which are normally eaten raw that have been exposed to Salmonella through cross-contamination or contaminated water.
The main sources of Salmonella infection include
- Raw vegetables or salad greens which have not been thoroughly washed
- Raw fruits which have not been washed
- Raw or undercooked
Contamination may originate in the fields when produce is irrigated with contaminated water. It may also occur during commercial food processing or may begin in the kitchen when raw meat juices come into contact with foods that are eaten raw such as salads. It may also be caused by people who do not adequately wash their hands after using the toilet, changing a diaper, touching a pet, or working with raw foods.
Notable Salmonella Food Outbreaks
The CDC estimates that over 1 million Americans may get Salmonella poisoning each year. Most of these do not cause symptoms or cause symptoms that are mild and not bothersome. Over 20 thousand people, however, become ill enough to require hospitalization and more than 300 people die each year due to salmonellosis.
There are a number of types of Salmonella bacteria, the most well-known of which is Salmonella typhi which is responsible for Typhoid fever. The other most common type in the U.S. is Salmonella enteritidis but both have similar symptoms.
As of September 2018, 12 outbreaks have been recorded in the U.S. but none have been fatal. Outbreaks have included:
- Eggs – two events
- Raw Turkey
- Pasta Salad
- Pre-cut melon
- Dried coconut
- Frozen coconut
- Chicken salad
- Raw sprouts
- Honey Smacks cereal
Since 2006, large-scale and notable events have involved:
- Peanut butter – 3 events involving thousands of patients and at least 9 deaths
- Alfalfa sprouts – 7 events
- Ground meats (chicken, turkey, beef) – 10 events
- Prepared entrée products – 7 events
- Nut butter (not peanut butter) – 3 events
- Nuts – 3 events
- Cantaloupe – 2 events
- Dry snacks or cereal – 3 events
- Eggs – 2 events
- Seafood – 2 events
- Papayas – 2 events
Notable events with deaths included:
2008 – 1,442 people were sickened in 43 states and 2 people may have died due to jalapeno and serrano peppers
2009 – Between 2008 and 2009, 714 people were sickened in 46 states and 9 people died from Salmonella in peanut butter
Hundreds of thousands of people are also affected by contamination events which occur at home and many are not reported because the illness is not severe. Certain animals may also cause salmonella contamination including live poultry, guinea pigs and lizards.
Symptoms of Salmonella
Salmonella symptoms usually occur within a few hours of food consumption by may be delayed by up to 10 days. In most cases, the patient will recover at home within 4 to 7 days but when diarrhea is severe, dehydration may become an issue requiring hydration in a hospital setting. In certain cases, the bacterial infection may spread beyond the intestines and result in chronic inflammatory disease or may even cause death.
The most common symptoms of salmonellosis include:
- Stomach cramps
- Nausea and vomiting
- Fever, cold, chills
- A headache
- Bloody stools
Most people will recover on their own without treatment, but it may take several months before bowel habits return to normal. When diarrhea has been severe, some patients will become dehydrated. This may result in medical complications and often requires hospital-based treatment. Symptoms of dehydration include:
- Little to no urine production
- Dry mouth and tongue
- Sunken or dry eyes
- Extreme thirst
- A headache
Symptoms of dehydration should be reported immediately.
In serious cases, though rare, Salmonella bacteria may spread beyond the gastrointestinal system and affect other body systems including the brain, heart, bones and blood vessels. Infections over 101.5, changes in consciousness, or heart rhythm disturbance should be treated as a medical emergency.
Longer term, some patients may develop a chronic inflammatory condition known as reactive arthritis which may result in joint pain, irritation of the eye or painful urination. It may last for months to years and is difficult to treat.
Treatment of Salmonellosis
In most cases, the patient will recover with little or no treatment, but more severe cases will require hospitalization to rehydrate the body. Antibiotics may be given to help eliminate the infection and supportive care will be offered.
In general, food poisoning should not be treated with anti-diarrheal medications unless recommended by a physician. Anti-diarrheal medications may slow the elimination of the bacteria from the intestines and prolong or worsen the illness.
Children under 5 are most at risk from Salmonella food poisoning but should never be given antidiarrheal medication except under the advice of a physician. Children are more prone to dehydration and any suspected food poisoning in a child should be reported to a physician immediately.
Preventing Salmonella Food Borne Illness
Salmonella may be difficult to detect as it does not usually smell or taste bad. There are a number of things that can be done to prevent Salmonella poisoning. Tips for preventing Salmonella exposure include:
- Wash raw produce before eating, even if purchased as “prewashed”
- Wash fruits before eating them, include fruits with an inedible rind or peel like cantaloupe
- Do not eat raw or runny eggs
- Do not eat raw or undercooked beef, poultry, pork or seafood. Cook meats to the correct temperature
- beef, pork, lamb and fish – 145 F
- ground beef, pork or lamb – 160 F
- poultry (chicken, duck, turkey) – 165 F
- eggs – no visible liquid remains
- Refrigerate food properly, before and after cooking it
- Do not allow food to sit at room temperature. Serve hot food hot and cold food cold
- Do not mix raw and cooked foods
- Do not prepare raw vegetables with the same utensils used to prepare raw meats
- Keep food preparation surfaces clean
- Wash hands with soap and warm water for at least 20 seconds after using the restroom, touching animals, or after preparing food
Most cases of Salmonella food poisoning are caused by contamination events which occur in the home or only cause minor symptoms. Those that occur due to contamination at commercial facilities, farms or restaurants may affect hundreds or even thousands of people and may cause serious illness or even death. In these cases, businesses may be held responsible for their inadequate safety practices.
People who were exposed to and became ill due to a commercial food contamination of Salmonella should seek legal advice. They may be eligible for compensation for their medical costs, pain, and suffering and other damages or for wrongful death when a victim has died.