What is the Difference Between Salmonella typhi and Salmonella typhimurium

The key difference between Salmonella typhi and Salmonella typhimurium is that Salmonella typhi is a bacterial serotype that causes typhoid fever in humans, while Salmonella typhimurium is a bacterial serotype that causes gastroenteritis in humans.

Salmonella is a genus of gram-negative bacteria. This genus belongs to the family Enterobacteriaceae. Salmonella was named after the American veterinary surgeon Daniel Elmer Salmon (1850-1914). There are two accepted species of the genus Salmonella: Salmonella enterica and Salmonella bongori. Salmonella typhi and Salmonella typhimurium are two serotypes of over 2500 serotypes of Salmonella enterica.

CONTENTS

1. Overview and Key Difference
2. What is Salmonella typhi  
3. What is Salmonella typhimurium
4. Similarities – Salmonella typhi and Salmonella typhimurium
5. Salmonella typhi vs Salmonella typhimurium in Tabular Form
6. Summary – Salmonella typhi vs Salmonella typhimurium

What is Salmonella typhi?

Salmonella typhi is a serotype of over 2500 serotypes of Salmonella enterica. This bacterium can only infect humans. It causes typhoid fever. This bacterial infection is more common in developing countries where hygiene is very poor, and water is contaminated from sewage. The symptoms of typhoid fever include fever, weakness, stomach ache, headache, and loss of appetite. Without proper and prompt treatment, Salmonella typhi infection can lead to liver damage, inflammation of the heart, holes in the gut, constipation, and internal bleeding. Some people may develop a skin rash with rose-colored spots. In severe cases, people may experience confusion. Normally, without treatment, symptoms may last weeks or months. Diarrhea is uncommon in typhoid fever. Typhoid fever is considered an enteric fever along with paratyphoid fever.

Salmonella typhi bacteria can grow in the different regions of the human body, including the intestine, Peyer’s patches, mesenteric lymph nodes, spleen, liver, gallbladder, bone marrow, and blood. Moreover, typhoid is spread by eating or drinking food or water contaminated with the feces of an infected person. There are no animal reservoirs for this particular bacterial serotype. The diagnosis of typhoid fever is made through blood, bone marrow, and stool culture, Widal test, and rapid diagnostic tests such as Tubex, Typhidot, and Test-It. Furthermore, the treatments for typhoid fever include rehydration therapy, oral antibiotics (ciprofloxacin, ceftriaxone, cefixime, ampicillin, trimethoprim-sulfamethoxazole, and amoxicillin), surgery for intestinal perforation and cholecystectomy.

What is Salmonella typhimurium?

Salmonella typhimurium is a serotype of over 2500 serotypes of Salmonella enterica. Salmonella typhimurium can cause infections in both humans and animals. This serotype is often associated with animals and animal products that are eaten. This serotype normally transmits to humans through raw or undercooked infected food, including meat and eggs. In poultry, this bacterial serotype is passed from bird to bird through their droppings.

Salmonella typhimurium causes gastroenteritis or inflammation of the gut. Gastroenteritis leads to diarrhea, vomiting, fever, and abdominal cramps. These symptoms may last up to seven days. Diagnosis of gastroenteritis can be made through physical examination, testing, stool and body fluids, culture media-based techniques (SM2 chromogenic media, Rappaport Vassiliadis broth), biochemical testing (API-20E system), and KW serogrouping. Treatment options for gastroenteritis include antidiarrheals (medications such as Ioperamide (Imodium A-D) and antibiotic medications such as ciprofloxacin.

What are the Similarities Between Salmonella typhi and Salmonella typhimurium?

• Salmonella typhi and Salmonella typhimurium are two serotypes of Salmonella enterica.
• They belong to the genus Salmonella and the family Enterobacteriaceae.
• Both serotypes cause infections in humans.
• They can be transferred to humans through contaminated foods.
• The diseases caused by both serotypes can be treated through antibiotics.

What is the Difference Between Salmonella typhi and Salmonella typhimurium?

Salmonella typhi is a bacterial serotype that belongs to the genus Salmonella and causes typhoid fever in humans, while Salmonella typhimurium is a bacterial serotype that belongs to genus Salmonella and causes gastroenteritis in humans. Thus, this is the key difference between Salmonella typhi and Salmonella typhimurium. Furthermore, diarrhea is uncommon with the infection of Salmonella typhi, while diarrhea is very common with the infection of Salmonella typhimurium.

The below infographic presents the differences between Salmonella typhi and Salmonella typhimurium in tabular form for side by side comparison.

Summary – Salmonella typhi vs Salmonella typhimurium

Salmonella typhi and Salmonella typhimurium are two serotypes of Salmonella enterica species of the genus Salmonella. Salmonella typhi causes typhoid fever in humans, while Salmonella typhimurium causes gastroenteritis in humans. So, this is the key difference between Salmonella typhi and Salmonella typhimurium.

Reference:

1. “Salmonella Typhimurium.” Microbewiki.
2. “Typhoid Fever (Salmonella Typhi).” BC Centre for Disease Control.

Image Courtesy:

1. “Typhoid bacteria (Salmonella typhi)” By Sanofi Pasteur  (CC BY-NC-ND 2.0) via Flickr
2. “Salmonella Typhimurium Gram” By Y tambe – Own work (CC BY-SA 3.0) via Commons Wikimedia