What is salmonella poisoning?
Salmonella poisoning, also known as salmonellosis, is an infection of the intestines caused by bacteria. You can get salmonella from drinking water or eating food that is contaminated (known as food poisoning), or by touching an infected animal.
According to Centers for Disease Control and Prevention (CDC) Data, about 1.35 million people are infected by salmonella every year in the U.S., resulting in 26,500 hospitalization and 420 deaths annually. Hospitalization might be necessary in people who become very dehydrated, or if the infection spreads to the bloodstream.
Salmonellosis causes diarrhea, abdominal cramps, and fever. Most people just need to rest and drink plenty of fluids, and will start to feel better within 4 to 7 days. Some people are at higher risk for severe illness and might need to take antibiotics.
Most common symptoms
A Salmonella infection typically lasts a few days, although symptoms can last up to a week. If you’re not feeling better at that point, it’s time to see your doctor. You might need additional tests to make sure that the diagnosis is correct, or different treatment, like antibiotics. —Dr. Anne Jacobsen
After you are exposed to Salmonella, symptoms of salmonellosis may show up anywhere from 6 hours to 6 days later, and last for 4 to 7 days. Most people will have diarrhea—watery stool that happens more than 3 times per day (you may see blood in the stool as well). Abdominal cramping pain is also common and you may have a fever.
In some people, Salmonella can cause a more serious infection and even spread to the bloodstream. Symptoms include a high fever, more frequent diarrhea or vomiting, dark urine, and other signs of dehydration.
- Abdominal cramps—throughout the belly, not just in one area
- Fever greater than 100.4℉
Other symptoms you may have
- Nausea and vomiting
- Dizziness or lightheadedness
Signs of severe infection
- Many episodes of diarrhea or vomiting
- Not able to keep fluids in your system because of vomiting or diarrhea
- Fever over 102℉
- Severe dizziness or lightheadedness
- Decreased urine or dark urine
- Large amount of blood in stools
- Children younger than 5 years old are more susceptible to it. Infection can be more serious in infants (less than 1 year old), who are more likely to become dehydrated.
- People who take antacids for heartburn are at greater risk, because lower levels of stomach acid can make it harder to kill the Salmonella bacteria.
- Intestinal diseases like Crohn’s disease or ulcerative colitis can make the intestines more vulnerable to bacterial attacks.
- Infection may be more serious in older adults (older than 65 years old), who are more likely to become dehydrated.
- People who have weakened immune systems due to HIV or chemotherapy can also have a harder time fighting the infection and are more likely to develop severe symptoms.
People who are normally in good health will usually be able to recover at home.
You should call your doctor if you believe you were exposed to Salmonella bacteria or if you have diarrhea that lasts longer than 7 days. You may need to give a stool sample so the laboratory can check for Salmonella.
You should also contact your doctor if you suspect that your infant has salmonellosis, or if you are over age 65 or have a weakened immune system. These groups might need to take antibiotics.
You should go to the ER if you have a fever greater than 102℉, bloody diarrhea, severe abdominal pain, uncontrolled vomiting, dark urine, or severe dizziness. These symptoms may mean you have serious illness, dehydration, or a condition other than salmonellosis.
You don’t need to actually touch an animal to become infected with Salmonella. Even being inside its habitat or touching other objects in its living space can cause you to be exposed. Make sure you wash your hands (and remind your children to do the same!) if you’re around farm animals or wildlife, or visiting the zoo. This even includes pond water! —Dr. Jacobsen
Salmonella bacteria is spread when people eat or drink contaminated foods or water. Food can become contaminated when it is handled or prepared improperly. For example:
- Raw vegetables can be contaminated if they touch the juices of raw chicken.
- People who don’t wash their hands well after using the restroom can spread bacteria when they prepare food.
- Food that isn’t cooked or cooled properly can allow growth of existing bacteria.
- Many foods could be a source of infection: Fruits, vegetables, poultry, seafood, and processed foods have all been linked to outbreaks.
Water that becomes contaminated with infected stool can also cause salmonellosis.
Additionally, some live animals can spread Salmonella to people. Pet turtles have a reputation for carrying Salmonella, but a variety of reptiles, amphibians, ducks, and chickens have been known to spread this infection.
If you have symptoms of salmonella poisoning, try to rest and drink clear liquids to prevent getting dehydrated. You lose electrolytes (essential minerals) when you have frequent diarrhea, so you can try to drink juice or sports drinks as well.
If you feel hungry, eat bland foods that are easy to digest, like toast, crackers, bananas, or applesauce. Don’t take antidiarrheal medications like loperamide (Imodium) or bismuth subsalicylate (Pepto-Bismol) until you discuss with your doctor, as they can sometimes make your symptoms worse.
Most people recover within 7 days without needing antibiotics. If you’re normally healthy, antibiotics probably won’t help you recover faster or reduce your symptoms. The healthy bacteria living inside your intestines can help fight off this infection.
But your doctor may recommend antibiotics if you have symptoms for more than 7 days or if you have bloody diarrhea. Infants, people older than 50 years with chronic health problems, anyone older than 65 years, and people with weakened immune systems may be given antibiotics earlier in their illness. Antibiotics may start to help symptoms within a few days, but it’s always important to finish all the pills so that the infection is completely treated.
Some people may become dehydrated if they can’t drink enough to keep up with fluid lost to diarrhea. Signs of dehydration are decreased urine or dark urine, severe dizziness, or many bouts of diarrhea or vomiting.
If you’re severely dehydrated, you may need to receive fluids directly into a vein through an IV at the hospital. Many people will start to feel a little bit better right away, but the infection will still take time to go away.
Reporting foodborne illness
The incubation period for Salmonella is about 6 to 72 hours after you are exposed to the bacteria. —Dr. Jacobsen
It’s important to know if contaminated food is being sold in our local grocery stores, so there are systems in place to track and report outbreaks. If your stool test comes back positive for Salmonella, the laboratory will send the results to the state public health lab for additional testing. This can alert public health officials to a possible outbreak.
Sometimes sick people are interviewed about their food intake and activities right before they became ill, and this may reveal a common source. Government agencies identify and keep track of outbreaks, and help spread the word when one does occur.
Most people will recover completely within about a week, but the illness can last longer in people who need antibiotics, IV fluids, or an overnight stay in the hospital. Make sure you finish the entire course of antibiotics if they were prescribed.
Sometimes stool can be loose or more frequent than normal for a few months after having salmonellosis. In rare cases, people can develop joint pain due to arthritis after recovering from this infection.
Stool contamination is unfortunately a big culprit in the spread of this infection. Here are some ways to help avoid eating contaminated food including food safety tips:
- Always wash your hands thoroughly with soap and water after using the bathroom and before eating.
- Always wash your hands after touching animals or spending time in areas where they might live.
- Don’t prepare food for other people if you’re sick with diarrhea.
- Wash raw fruits and vegetables before eating.
- Keep raw meat and poultry away from other foods in your kitchen.
- Cook foods to the recommended internal temperature and use a food thermometer.
- Don’t leave leftovers sitting out of the fridge.