The type of treatment someone with a listeria infection requires depends on the patient and his or her symptoms. RELATED: The Signs and Symptoms of Listeria Infection Healthy, nonpregnant individuals with normal immune function may not require any treatment — or even feel sick enough to warrant a call to the doctor. (1) While these people may experience mild symptoms after eating food contaminated with listeria bacteria — such as a stomachache or diarrhea — symptoms will typically subside by themselves within one to three days, though they can last for up to a week. (2) RELATED: Why Listeria Makes You Sick But what about at-risk patients and those rare healthy people who experience a severe (or “invasive”) listeria infection? The Centers for Disease Control and Prevention (CDC) recommends different treatment protocols based on a patient’s symptoms. (1) So let’s say you’ve eaten a food that is part of a listeria-related outbreak or recall. Or maybe you grabbed a hunk of cheese from your fridge and realized after eating it that it was several weeks old. Until you experience symptoms associated with a listeria infection, your doctor likely won’t perform any testing or prescribe any antibiotics. (1) It’s important to note that while symptoms usually show up within 24 hours, they may take up to two months to emerge. (1) If you think you may have eaten a contaminated food, you should see your doctor if and when you experience nausea, diarrhea, fever, or any other signs of a listeria infection. (1) RELATED: When to See Your Doctor if You Have Diarrhea If you are experiencing symptoms and think you may have been exposed to listeria and you are pregnant, elderly, or immunocompromised, your doctor may pursue diagnostic testing to confirm a listeria infection — usually a blood test or other fluid test. Your doctor may also start you on a course of oral antibiotics. In other cases, your doctor may wait until a diagnostic test comes back positive to start you on antibiotics. The CDC says both options are common, and there’s no clear evidence showing one is more effective than the other. (1) In either case, if the diagnostic test comes back positive for a listeria infection, a course of intravenous (IV) antibiotics using the drugs ampicillin (Omnipen) and gentamicin (Garamycin) might be required for severe, invasive listeria infections (bloodstream, central nervous system, vascular, bone, or joint). The course of IV antibiotics would run for 14 to 21 days, with individuals hospitalized so that their risk of complication can be monitored (1). Doctors may try a different antibiotic if these two don’t work (or if the patient is allergic). This is handled on a case-by-case basis. If you have a fever (along with other symptoms of listeriosis), your doctor may start you on a course of IV antibiotics from the beginning, says Rob Danoff, DO, a family physician at Jefferson Health in Bensalem, Pennsylvania. “If the symptoms are severe, hospitalization for treatment is common.” Sometimes in higher-risk individuals who have only mild symptoms, oral antibiotics alone can be used to treat the infection. (3) If a pregnant woman does not have symptoms of listeria infection (even if she thinks she has been exposed to the bacteria), she does not need testing or antibiotics. The same is true if she has symptoms but no fever — although in these cases a doctor may order testing and recommend antibiotics as a precaution. (4) If a pregnant woman has a fever coupled with other listeriosis symptoms, her doctor will likely start her on a course of intravenous antibiotics while ordering blood or placenta testing to check for the infection. (4) RELATED: What All Pregnant Women Should Know About the Risks of Listeria But when it comes to more serious listeria infections, recovery timetables and outcomes are all over the map. Dr. Danoff says nearly all patients with severe infections that cause complications, like sepsis, meningitis, and others, will require hospitalization. And how long that hospital stay lasts depends on a patient’s age and underlying health status, as well as the type of listeria-related infection they experience. Tragically, roughly 15 percent of patients with invasive listeriosis die. (7) Fortunately, quick diagnosis and treatment is often very effective, Danoff says. If people — especially those at high risk — are careful about what they eat and quick to notify their doctor of symptoms they do experience, they have a good chance of knocking out the infection before it can invade their blood and cause more serious health problems. RELATED: How to Prevent Listeria Infection
