Salmonella: Everything You Need to Know

Medically reviewed by Jordana Haber Hazan, MDMedically reviewed by Jordana Haber Hazan, MD

Salmonella is one of the most significant causes of food-borne illness worldwide. The bacteria can live in and cause infections in animals and humans.

Experts estimate that salmonella bacteria causes about 1.35 million illnesses, 26,500 hospitalizations, and 420 deaths in the United States every year.

This article discusses how and where you get salmonella poisoning, risk factors, symptoms, treatment, and prevention.

<p>Anjelika Gretskaia / Getty Images</p>

Anjelika Gretskaia / Getty Images

How Do You Get Salmonella Poisoning?

Salmonella can be transmitted to humans through improper food handling and preparation and from person to person or animal to person. It's usually transmitted to humans by eating foods contaminated with animal feces.

Many food sources can be contaminated with salmonella, especially if they are not cooked properly, are in the heat for too long, or have been exposed to the bacteria from an infected person. Often, food and water contaminated with salmonella look and smell normal.

Uncooked Meat, Seafood, and Poultry

The most common way to get salmonella poisoning is through consuming contaminated food of animal origin (eggs, meat, poultry, fish, and milk). Other foods like fruits and vegetables can carry salmonella if they have been contaminated by manure.

You can get sick if contaminated meat, seafood, and poultry are not cooked properly. Cooking foods at proper temperatures can prevent salmonella and kill any potential microbes.

Uncooked Eggs

Salmonella bacteria can get on the shells of eggs when chickens lay them or when eggs touch poop. Typically, because eggs are washed before they reach stores, it's not a problem. However, salmonella can get inside the eggs when the egg forms inside the chicken. While rare, avoiding eating raw eggs and cooking eggs thoroughly is still important.

Fruits and Vegetables

Fruits and vegetables may be contaminated with salmonella through water or soil. The risk is lower when cooked, washed, prepared, and stored properly. It's best to store fresh produce away from raw meat, fish, and poultry. Juices of raw meat or poultry left on a cutting board or kitchen surface that touches fruits and vegetables can also increase the risk of salmonella.

Lack of Hygiene

If you have salmonella, are experiencing diarrhea, and don't wash your hands, you can spread it to others. Avoid food handling until your diarrhea stops. Washing hands after using the toilet, changing diapers, or assisting someone sick with diarrhea is essential.

Pet Reptiles and Amphibians

Reptiles like turtles, lizards, and snakes are particularly likely to harbor salmonella because they often carry the bacteria in their digestive tracts. Even pets that appear to be healthy can carry salmonella. It is recommended that you wash your hands after handling reptiles or their environments (tanks, water, and food).

Risk Factors for Salmonella

Anyone can get a foodborne illness. Certain people are at increased risk of getting salmonella, including those with:

  • Weakened immune systems

  • Autoimmune diseases

  • Diabetes

  • Organ transplants

  • Cancer

  • HIV

  • Pregnancy

  • Children younger than 5 and adults 65 and older

People who take medications that reduce stomach acid may also be at increased risk.



Takeaway


Salmonella occurs more frequently in the summer (June, July, and August). Higher temperatures and unrefrigerated foods increase the chances of growing the bacteria. Refrigerate foods within two hours or one hour if the temperature outside is 90°F or hotter.



Salmonella Symptoms

Salmonella symptoms can occur between six to 72 hours (usually 12 to 36 hours) from ingestion and last two to seven days. Common symptoms include:

  • Fever (almost always)

  • Diarrhea (comes on suddenly and can be bloody or contain mucous)

  • Abdominal cramps or pain

  • Headache

Most people recover without medical intervention. However, salmonella infection can be more serious in older adults, infants, and people with chronic conditions. In rare and severe cases, it can cause joint pain, painful urination, and eye irritation (Reiter's syndrome).

Invasive salmonella, which accounts for about 8% of people with confirmed infection, can cause infections in the blood (bacteremia), the lining of the brain and spinal cord (meningitis), and the bone (osteomyelitis).

Is Salmonella Contagious?

An infected person spreads salmonella through food handling and the sharing of utensils or food. If a person touches a surface with salmonella and then puts their hands in their mouth, they can also become infected. The most common way to contract salmonella is by eating or drinking food or water that contains it.

How Long Does Salmonella Last?

The duration and severity of symptoms will depend on the infected person and the serotype they are infected with. Some types cause severe illness, while others cause mild symptoms.

Preventing the Spread of Infection

Salmonella prevention includes proper food handling (cooking, preparation, and storage) and hand washing. Stay home if you are sick, and do not cook or prepare food for others when you are symptomatic to avoid spreading infection. Prevent salmonella by cooking foods at proper temperatures, avoiding poultry or chicken that is pink inside, or undercooked eggs.

How Do I Know If I Have Salmonella?

Salmonella can be detected in a person's stool (poop), body tissue, or fluid. A stool sample or blood can be tested to determine if you have salmonella. A healthcare provider will ask you for a history of your symptoms and do an abdominal exam. If they suspect a salmonella infection, they may or may not require additional testing.

How Is Salmonella Treated?

Most people recover in four to seven days without treatment. Antibiotics are typically used only for severe illness. People with salmonella infection should drink extra fluids and rest. Small sips of fluids with electrolytes or ice chips may help if you have trouble keeping beverages and foods down. Hospitalization may be needed for dehydration.

Over-the-counter pain medication can help with headaches, belly pain, and fever. A heating pad can also soothe stomach cramping.

Although rare, the infection may spread from the intestines to the bloodstream and other body parts. This can become serious and, without prompt antibiotic treatment, could lead to death.

How to Prevent Salmonella

Taking safety measures when prepping, storing, and cooking foods is an easy way to prevent salmonella infection. Cooking food properly kills off potential bacteria.

Other prevention tips include:

  • Washing fruits and vegetables well.

  • Thawing frozen food in cold water, the refrigerator, or microwave. Thawing food at room temperature can increase the risk of salmonella. Foods that have been thawed should be cooked to a safe internal temperature after thawing.

  • Keeping countertops clean, using disposable paper towels to wipe down surfaces, and hot, soapy water to clean up any raw meat or poultry residue.

  • Using separate cutting boards to handle raw meat and vegetables prevents cross-contamination.

  • Serving food on clean plates, and never place cooked food on a plate with raw meat.

  • Washing hands before and after handling raw food and after petting animals.

Hand Washing

Unwashed hands can spread salmonella if a person handles food that is contaminated. It's recommended to wash your hands with warm, soapy water for at least 20 seconds before and after food handling, as well as after:

  • Using the bathroom

  • Changing a diaper

  • Handling pets

  • Tending to a sick person

  • Blowing your nose, coughing, or sneezing

  • Handling uncooked eggs, raw meat, poultry, or fish

Food Handling

When shopping, keep fresh produce, raw meat, poultry, and fish separate in your cart and shopping bags. Separate raw meat products from ready-to-eat foods and deli meat. After preparing meat on a cutting board, don't use it to cut vegetables or other fresh foods without adequately washing them.

The best way to protect yourself is to cook food to a proper internal temperature and measure it using a food thermometer. You will also want to reheat leftovers until they are hot. Food left out at high temperatures should not be kept after one hour. Perishable food items should be appropriately chilled and not left out for more than two hours at room temperature.

Egg Safety

Keep eggs in the original carton and store them in the main part of the refrigerator, not in the door. Cook eggs until both the yolk and white are firm. Do not consume raw eggs or foods that contain raw eggs like cake batter or cookie dough.

Pets

Pets can pass salmonella through their stool or contaminated saliva. Your pet is more likely to have salmonella and another infection and will experience the same symptoms as humans. The best way to keep your pet safe and healthy is to have regular vet checkups, including well visits.

When to Contact a Healthcare Provider

Speak with a healthcare provider if symptoms are not improving after a few days. This includes a fever with diarrhea for more than three days, bloody stools, and prolonged vomiting that prevents you from keeping down liquids. Call a healthcare provider if you experience dehydration symptoms like little urine output, dry mouth and throat, or dizziness.

Summary

Salmonella is a type of bacteria that can be found in many different types of foods. The most common way to contract salmonella is by consuming contaminated food of animal origin (eggs, meat, poultry, fish, and milk). However, proper storage, preparation, and cooking techniques can prevent infections.

Understanding food safety and good hygiene can prevent salmonella infection. Call a healthcare provider if you contract salmonella and experience signs of dehydration, prolonged diarrhea, vomiting, or fever.

Read the original article on Verywell Health.