There are countless ways salmonella bacteria can contaminate the food we eat. Whatever route it takes, salmonella infects the gut. Once infection takes hold, symptoms like diarrhea and fever can happen in just a few hours. Fortunately, infections typically resolve themselves without any outside interference. Learn more about the symptoms and treatment of salmonella in the sections that follow.
Salmonella is a common bacterial infection of the intestines and the most common cause of food poisoning. Over a billion people pick up a salmonella infection each year, and almost one and a half million of those folks live in the United States. Fortunately, most salmonella cases only infect intestinal tissues and clear up without treatment after a few days of diarrhea. For most salmonella cases, the primary threat is dehydration and loss of electrolytes.
However, the typhoid strains of Salmonella (Salmonella enterica variants—typhi and paratyphi) easily make their way through intestinal tissues, invade the body, and cause typhoid fever, one of the deadliest infectious diseases on the planet. Also called enteric fever, typhoid fever infects 21 million people a year and kills over 200,000 of them. Fortunately, typhoid fever is very rare in the United States, averaging about 400 cases a year, and almost all those patients catch the infection overseas.
Salmonella, then, is divided into two diseases. Typhoidal salmonella causes enteric fever. Non-typhoidal salmonella, or NTS, usually causes transient intestinal infections that, on rare occasions, may sometimes progress to a system-wide infection. In the United States, salmonella almost always refers to non-typhoidal salmonella, so we’ll focus on that disease with an occasional reference to typhoid fever.
Non-typhoidal Salmonella is passed from animals to humans. The normal route of transmission is for people to eat animal feces populated with Salmonella bacteria but more than 95% of salmonella infections in the U.S. are food-borne, that is, people are eating food contaminated with feces. Considering that salmonella infects the majority of farm animals —especially chickens—it’s not hard to imagine how easily food can be contaminated.
Meat, especially ground beef or pork, can be contaminated when being processed. Eggs can be infected when they’re formed in the chicken, or afterward, the shell can become contaminated. Vegetables and fruit can be contaminated by fertilizer or by being processed or prepared along with contaminated meats. Food handlers with poor hygiene can contaminate foods. Handling or cleaning up after pets can spread salmonella to the hands, which can then contaminate food. There are a million ways for Salmonella bacteria to get into a person’s digestive system, but the basic equation always remains the same.
Typhoid fever, however, only infects humans. The infection is passed from person to person through feces. The risk factors for typhoid fever, then, are poor sanitation, untreated drinking water, and overcrowding, so travel to developing countries includes a risk for typhoid fever.
A Salmonella infection, called salmonellosis, is always a prime suspect when a patient has diarrhea and fever. Healthcare providers only diagnose salmonella when they’ve confirmed the presence of Salmonella in the patient’s stools, urine, or blood.
To understand the risk for salmonellosis, it helps to understand what it takes to catch an infection. Salmonella bacteria have several formidable obstacles to overcome before they can cause an infection. First, they have to end up on food. They are wiped out if the food is cooked or cleared out if the food is washed. If the bacteria make it past that first hurdle, they then have to survive deadly acid in the stomach, which most don’t survive. Once in the intestines, normal intestinal motility sweeps them out before they can do anything. Those that don’t get swept out still have to face bacteria already living in the intestines, some of which can poison what little Salmonella remains. Finally, the immune system takes on the stragglers, clearing them out before an infection takes hold.
Considering all those hurdles, the risk factors for salmonella infection are
Symptoms appear in six to 48 hours. Diarrhea is the cardinal symptom, but patients often have nausea, vomiting, and abdominal cramps. Fever, chills, headache, bloody stools, and muscle pain are also common.
Typhoid fever, on the other hand, typically takes five to 21 days for symptoms to manifest. It may be preceded by intestinal swelling (gastroenteritis) with abdominal pain and either diarrhea or constipation. The most characteristic symptom of typhoid fever is a “stepwise” fever in the first week of infection—the body’s temperature increases, levels off for a while, then increases some more, plateaus again, and so on, eventually reaching a sustained, high fever. Stepwise fever is followed by the other distinguishing symptom of typhoid fever, a rash of “rose spots.”
Salmonellosis is only diagnosed when Salmonella is found in the stools either by culturing the bacteria or detecting antibodies. Typhoid fever is confirmed by culturing a blood sample, running antibody tests on blood or urine, or detecting Salmonella genes in the blood.
Approximately 0.5% of patients who get non-typhoidal salmonella and 3% of patients with typhoid fever become salmonella carriers without any symptoms; “Typhoid Mary” being the first and most famous. A carrier continues to pass salmonella bacteria in their stools and urine for years and can continue to spread the infection. Called “asymptomatic carriage,” the carrier form of salmonellosis is diagnosed with regular stool samples but is usually only monitored in patients with typhoid fever. Since most non-typhoidal salmonella infections go undiagnosed and untreated, asymptomatic carriers usually go undiagnosed.
Non-typhoidal salmonellosis typically resolves in a few days without treatment, but if the infection threatens to spread, then medications, hospitalization, and even surgery may be required.
Most non-typhoidal Salmonella infections will be treated with rest and rehydration. Patients with severe diarrhea or dehydration, however, will be hospitalized and put on intravenous fluids and electrolytes. Antibiotics can make the condition worse so they’re not recommended.
The most serious complication for non-typhoidal Salmonella is a blood infection, or bacteremia, a potentially life-threatening infection that happens in 1-4% of cases. When this happens, about one in 10 patients will advance to more serious localized salmonella infections such as pneumonia, meningitis, osteomyelitis, or reactive arthritis. These cases are always treated with antibiotics. Some patients are more at risk for complications than others, such as young children and the elderly, so they will often be put on antibiotics before the infection spreads.
Typhoid fever is always treated with antibiotics, if possible. The mortality rate for untreated typhoid fever is 10-30%; antibiotic treatment lowers the mortality rate to 1%. Also, typhoid fever can cause intestinal tearing (perforation) that will require surgery.
Treatment for carriers involves a four-week course of antibiotics. Because the gallbladder can house a salmonella colony, it is usually the cause of asymptomatic carriage. If antibiotic treatment doesn’t work, surgical removal of the gallbladder, or cholecystectomy, may be necessary.
Non-typhoidal salmonella is treated with rest and rehydration, but both enteric fever and complicated salmonella infections will be treated with antibiotics. Salmonella infection is so common, however, that drug-resistant strains are prevalent. Many antibiotics that used to fight off salmonella can no longer be used.
The initial antibiotic treatment for cases where salmonellosis is suspected but not confirmed is a third-generation cephalosporin such as ceftriaxone. Once a complicated salmonella infection or typhoid fever has been confirmed, the preferred antibiotics are fluoroquinolones (ciprofloxacin, ofloxacin, or fleroxacin), azithromycin, or ceftriaxone. Drug-resistant salmonella is always a risk, so treatment may have to switch to carbapenems (ertapenem or meropenem) particularly if the infection is acquired in Pakistan. . Patients with complicated NTS usually require seven to 10 days of antibiotics, but typhoid fever usually involves 10-14 days of treatment. Carriers will need to endure four weeks (or longer) of fluoroquinolones to clear the infection.
There are no vaccines for non-typhoidal salmonellosis, but there are two typhoid fever vaccines: oral Vivotif and injectable typhoid vaccine. Both are equally effective, so the choice will depend on the age of the patient and the number of years of immunity required. The Centers for Disease Control (CDC) recommend typhoid fever vaccination for all Americans traveling to developing countries.
Patients with either non-typhoidal or typhoidal salmonellosis might use over-the-counter or prescription medications to relieve abdominal pain or nausea.
The most severe and deadly cases of typhoid fever will be treated with high doses of dexamethasone along with antibiotics. Dexamethasone is a corticosteroid that is used in typhoid fever to reduce potentially life-threatening swelling in the brain.
Most cases of salmonella resolve without drug treatment. Antibiotics are only used if the infection spreads to the rest of the body. Healthcare providers use an established set of guidelines for prescribing antibiotics for salmonella infections, so there is no “best” antibiotic for salmonellosis.
Best medications for salmonella | ||||
---|---|---|---|---|
Drug Name | Drug Class | Administration Route | Standard Dosage | Common Side Effects |
Cipro (ciprofloxacin) | Fluoroquinolone antibiotic | Oral | One 500 mg tablet every 12 hours | Nausea, diarrhea, liver problems |
Floxin (ofloxacin) | Fluoroquinolone antibiotic | Oral | One 200 mg tablet every 12 hours | Nausea, headache, insomnia |
Zithromax (azithromycin) | Macrolide antibiotic | Oral | Two 250 mg tablets on day 1 followed by one 250 mg tablet daily on days 2-5 | Diarrhea, nausea, abdominal pain |
Rocephin (ceftriaxone) | Cephalosporin antibiotic | Injection | One to two grams injected daily in divided doses | Blood problems, liver problems, diarrhea |
Invanz (ertapenem) | Carbapenem antibiotic | Infusion | One gram infused daily (optimum dose is not established for typhoid fever) | Diarrhea, vein problems, headache |
Typhim Vi (salmonella typhi ty2 vi polysaccharide antigen) | Vaccine | Injection | One injection of 0.5 ml of 25 mcg/0.5 ml | Injection site reactions, headache, malaise |
Vivotif (salmonella typhi ty21a) | Vaccine | Oral | One capsule taken before a meal on days 1, 3, 5, and 7 for a total of four capsules | Abdominal pain, nausea, headache |
Many of the standard dosages above are from the U.S. Food and Drug Administration (FDA). Dosage is determined by your doctor based on your medical condition, response to treatment, age, and weight. Other possible side effects exist. This is not a complete list.
Different classes of antibiotics have different side effects. However, this is not a complete list of side effects, and you should consult with a healthcare professional for possible side effects and drug interactions based on your specific situation.
Antibiotics typically cause upset stomach, intestinal problems, diarrhea, constipation, and loss of appetite. The most serious side effect of antibiotics is an allergic reaction which occurs in roughly one out of 15 people. Healthcare providers will avoid certain types of antibiotics that are known to cause reactions in a patient.
Typhoid fever vaccines are safe and have relatively few side effects. The oral typhoid vaccine has few and uncommon side effects including abdominal pain, nausea, headache, fever, and diarrhea. Patients are more likely to experience side effects with the injectable vaccine including feeling bad (malaise), headache, and injection site reactions.
The best home remedy for salmonella is to not get infected in the first place. In the United States, non-typhoidal salmonellosis is almost entirely a food-borne illness, so preventing infection only requires a few common-sense food safety precautions:
Even if you do everything right, you can still contract a salmonella infection. Salmonella outbreaks have been caused by restaurants, markets, and even processed foods, such as peanut butter, ice cream, pot pies, and breakfast cereal. If you do catch salmonella, home remedies are often the preferred treatment:
Most cases of non-typhoidal salmonellosis are treated without antibiotics. In fact, antibiotics may cause the infection to last longer. Typhoid fever, however, is always treated with antibiotics.
Patients with non-typhoidal salmonellosis could be hospitalized for dehydration due to diarrhea or if the infection spreads to the blood (bacteremia).
Native bacteria and yeasts in the intestines often produce toxins that are fatal to Salmonella. For this reason, antibiotic treatment or gastrointestinal surgery that alters the native microbial environment in the intestines is a significant risk factor for salmonellosis. However, there is no scientific evidence that people with a healthy microbial environment in the intestines can prevent or treat salmonella infections with probiotics. The best anyone can say is that it doesn’t hurt.
The first-line treatment for salmonella infections are fluoroquinolones, such as ciprofloxacin, and azithromycin. Third-generation cephalosporins are also effective, and often they are the first antibiotic given if a salmonella infection is suspected but not confirmed.
As with any condition that causes diarrhea, the most important thing you can do is drink water and take electrolytes. It is a good idea to see a healthcare provider and confirm that you have a salmonella infection. The healthcare provider will probably not prescribe medications but will alert you to monitoring for complications.
Most non-typhoidal salmonella infections resolve in four to seven days. Typhoid fever typically responds rapidly to antibiotics. Patients will see a dramatic reduction in symptoms after two days of antibiotic treatment, and the infection typically clears in seven to 10 days.
Most cases of non-typhoidal salmonella are treated at home with rest, rehydration, and electrolyte replacement. The infection usually subsides in four to seven days.
Even after symptoms resolve, people expel bacteria in their waste for an average of four weeks, but some people could remain contagious for months. A small number of people can become chronic, asymptomatic carriers and be contagious for years.
Salmonella is a bacteria and fungicides fight off yeasts and molds. Salmonella is treated with antibacterial drugs.
In most cases, salmonella goes away on its own without drug treatment. Typhoid fever, which is very rare in the United States, will be treated with antibiotics because the mortality rate is high.
Dr. Anis Rehman is an American Board of Internal Medicine (ABIM) certified physician in Internal Medicine as well as Endocrinology, Diabetes, and Metabolism who practices in Illinois. He completed his residency at Cleveland Clinic Akron General and fellowship training at University of Cincinnati in Ohio. Dr. Rehman has several dozen research publications in reputable journals and conferences. He also enjoys traveling and landscape photography. Dr. Rehman frequently writes medical blogs for District Endocrine (districtendocrine.com) and hosts an endocrine YouTube channel, District Endocrine.
...(Except Major Holidays)
© 2024 SingleCare Administrators. All Rights Reserved.
* Prescription savings vary by prescription and by pharmacy, and may reach up to 80% off cash price.
Pharmacy names, logos, brands, and other trademarks are the property of their respective owners.
This article is not medical advice. It is intended for general informational purposes and is not meant to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. If you think you may have a medical emergency, immediately call your physician or dial 911.
This is a prescription discount plan. This is NOT insurance nor a Medicare prescription drug plan. The range of prescription discounts provided under this discount plan will vary depending on the prescription and pharmacy where the prescription is purchased and can be up to 80% off the cash price. You are fully responsible for paying your prescriptions at the pharmacy at the time of service, but you will be entitled to receive a discount from the pharmacy in accordance with the specific pre-negotiated discounted rate schedule. Pharmacy names, logos, brands, and other trademarks are the property of their respective owners.Towers Administrators LLC (operating as 'SingleCare Administrators') is the authorized prescription discount plan organization with its administrative office located at 4510 Cox Road, Suite 111, Glen Allen, VA 23060. SingleCare Services LLC ('SingleCare') is the vendor of the prescription discount plan, including their website.website at www.singlecare.com. For additional information, including an up-to-date list of pharmacies, or assistance with any problems related to this prescription drug discount plan, please contact customer service toll free at 844-234-3057, 24 hours a day, 7 days a week (except major holidays). By using the SingleCare prescription discount card or app, you agree to the SingleCare Terms and Conditions found at https://www.singlecare.com/terms-and-conditions
© 2024 SingleCare Administrators. All Rights Reserved.