Salmonella Infections
Salmonella infections, also known as salmonellosis, usually occur after eating raw or undercooked meat, chicken, eggs, or egg products. Once ingested, the salmonella bacteria passes through the stomach and can colonize the small and large intestine. This may cause salmonella food poisoning symptoms. In very rare cases (approximately 5% of all salmonella infections), the salmonella can spread to the blood, potentially damaging any organ within the body.
Conditions Caused by Salmonella Infections
Salmonella has three clinical forms:
- Gastroenteritis – When the salmonella infection primarily affects your digestive tract, it is termed gastroenteritis (also known as the stomach flu).
- Enteric Fevers – This type of salmonella infection is very severe and requires prompt treatment with antibiotics. Enteric fevers may accompany gastroenteritis, or may occur after. The most common and most studied form of enteric fever is known as typhoid fever.
- Septicemia – When the bacteria spreads to the blood, it is termed septicemia or sepsis. The spread of salmonella to the blood is very rare. Groups at higher risk of developing sepsis include infants, young children, the elderly, and patients who have compromised immunity.
The Incubation Period of Salmonella Infections
Salmonella food poisoning symptoms may take a few hours to around 2 days before they manifest. This period of time is known as an incubation period, or the time it takes for the bacteria to cause symptoms related to the illness.
Salmonella infections causing enteric fever may take up to three weeks before symptoms develop.
Salmonella Food Poisoning Symptoms
Salmonella Gastroenteritis Symptoms
When salmonella passes its incubation period, the following symptoms associated with gastroenteritis may occur:
- Diarrhea (which may or may not be tinged with blood)
- Melena (blood in the stool)
- Abdominal cramps
- Nausea and vomiting
- A loss in appetite
- Headaches
- Fever
- Chills
Not all symptoms will be present in patients with salmonellosis. In fact, the major symptom (cardinal symptom) of salmonellosis is diarrhea. This may be accompanied by a fever and chills.
The symptoms of salmonella gastroenteritis may last from 4 to 7 days, even without treatment. Diarrhea may persist for up to 10 days.
Salmonella Enteric Fever Symptoms
A person infected with salmonella can present with the following symptoms if they have an enteric fever form of the infection:
- High fever
- Anorexia
- Myalgia (muscle pain)
- Headache
- Constipation or diarrhea
If the condition is untreated and allowed to progress further, the patient may become delirious, weak, fatigued. This is known as a “typhoid state.” It is at this point that the patient is at risk for life-threatening complications.
Signs and symptoms of typhoid fever may recur up to two weeks after the fever has been resolved.
Salmonella Septicemia Symptoms
Salmonella infections affecting the bloodstream can present as an on and off fever. Individuals with septicemia may show respiratory symptoms and diarrhea, but this is not so prominent in this form of salmonella infection.
Salmonella Septicemia: Who Is at Most Risk for Severe Forms of the Disease?
As mentioned earlier, specific groups of people are at risk of severe salmonella infections. These groups include the very young, very old, and immunocompromised.
Those with the following illnesses are at greatest risk of developing severe salmonella:
- Cancer (patients taking chemotherapeutics for treatment)
Certain medical procedures, treatments, or conditions may also increase your risk of developing severe salmonella, such as:
- A splenectomy (removal of the spleen)
- Proton Pump Inhibitors (stomach acid suppression medicine)
What Symptoms Should I Look Out For?
If you notice the following symptoms, seek medical attention as soon as possible:
- Signs of dehydration
- Oliguria (little or no urine production)
- Dizziness upon standing (orthostatic hypotension)
- Dry mucous membranes (your mouth and/or throat)
- A fever of 38°C or higher that is accompanied by diarrhea
- Diarrhea that has lasted for 3 or more days with no signs of improvement
- Stool tinged with blood
- Nausea and vomiting that prevent you from drinking or keeping liquids in
Key Takeaway
Salmonella infections may have very different symptoms. It is important to be able to identify salmonella food poisoning symptoms, as this can help differentiate it from its more severe forms. The more common form of this infection, gastroenteritis, can pass through your system even without treatment, and may only require treatment for dehydration.
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