Is Salmonella Contagious or Infectious?

Salmonella bacteria cause infections via fecal-oral transmission. This happens when food, water, or objects carrying bacteria from poop, either human or animal, come into contact with your mouth.

Eating raw or undercooked meat is the most common way salmonella is spread. The Centers for Disease Control and Prevention (CDC) estimates that there are 1.35 million salmonella infections per year in the United States, with most cases resulting from contact with food (food poisoning).

Common food sources of infection include:

• beef
• pork
• chicken
• turkey
• fish

Raw meat can carry fecal bacteria that was present on the animal before it was slaughtered. Eggs from a contaminated bird can also carry Salmonella bacteria. Eating raw eggs in particular increases the risk ofsalmonella infection.

Unwashed fruits and vegetables can carry fecal bacteria as well. Bacteria can infect fruits and vegetables through fertilizer or contaminated water. Bacteria can also come from the waste of animals close to where the fruits or vegetables were grown.

As noted by the CDC in 2009, Salmonella has also been known to turn up in processed foods such as peanut butter, as occurred in the 2008-2009 outbreak, which was likely caused by infected birds or contaminated water runoff.

Some animals can also carry Salmonella bacteria, such as:

• lizards
• turtles
• iguanas
• baby chickens
• hamsters
• gerbils
• pet or wild dogs
• domestic or wild cats

Salmonellosis is contagious. Although transmission from person to person is rare, it can be spread by someone who’s contracted it even if they aren’t showing any symptoms or have undergone successful antibiotic treatment.

Sexual activities that expose you to fecal bacteria, such as anal sex, can make you vulnerable to contracting the bacteria.

Putting an object in your mouth that was touched by someone with an active infection can also spread salmonellosis.

The best prevention against the spread of salmonellosis is good personal hygiene. Be sure to thoroughly wash your hands before every meal and after every trip to the bathroom.

Salmonellosis symptoms usually last for about 4 to 7 days. A person can still transmit the bacteria for several weeks after symptoms fade, and even several months later.

The North Dakota Department of Health notes about 1 percent of adults and 5 percent of babies who contract salmonella still have traces of the bacteria in their stool for a year or longer.

Most Salmonella bacteria live on dry surfaces for up to 4 hours before they’re no longer infectious. But Salmonella’s survival rate also depends on its species. A 2003 study found that Salmonella enteritidis can survive for 4 days on a heavily contaminated surface.

You typically carry Salmonella bacteria in your body for 6 hours to 6 days before you show symptoms of salmonellosis. Some bacteria may not cause symptoms for months.

Once salmonellosis takes hold, you’ll start experiencing symptoms rather suddenly.

The best way to prevent salmonellosis is by taking measures to minimize your exposure to Salmonella bacteria. Do the following to keep yourself from contracting the bacteria. These tips will also help you avoid transmitting salmonellosis to others if you already have it:

• Don’t share anything with someone who has salmonellosis. Specifically, don’t share anything of yours that touches your hands or mouth when you have it.
• Don’t have sex if you or the other person has contracted the bacteria.
• Avoid sharing anything that’s touched your mouth with anyone else until you’re certain you’re no longer carrying the bacteria.
• Wash your hands immediately after handling animals such as birds, reptiles, amphibians, livestock such as cows and horses, and both wild and pet animals.
• Clean any surface that’s come into contact with raw meat or other raw foods that may carry bacteria.
• Wash your hands thoroughly before and after touching raw meat or unwashed fruits and vegetables.
• Don’t drink any raw, unpasteurized, or unpurified liquids, especially milk and water.
• Cook meat, eggs, and other animal products thoroughly to kill bacteria through heat.
• Refrigerate foods immediately after purchasing or preparing them.
• Check for food recall notices regularly at your local grocery stores. The websites for the Food and Drug Administration (FDA) and CDC also provide recall information.
• Throw away any food or dump any water that you suspect may be contaminated.

Salmonella is highly infectious. Avoid touching and sexual activity until you’re fully clear of the bacteria.

Call 911 or local emergency services and get medical attention if you start experiencing severe salmonellosis symptoms. Keep seeing a doctor or healthcare professional regularly after your symptoms have faded to test for the presence of the bacteria until they’re gone, especially if you work in food service, healthcare, daycare, or other vulnerable settings.