Difference Between Salmonella Typhi and Paratyphi

The key difference between Salmonella Typhi and Paratyphi is that Salmonella Typhi is the causative agent of Typhoid fever while Salmonella Paratyphi is the causative agent of Paratyphoid fever.

Typhoid fever and paratyphoid fever are two illnesses caused by bacterial infections. They are kinds of enteric fever. The causative agents of these two diseases are Salmonella Typhi and Salmonella Paratyphi, respectively. These two bacteria are serotypes of Salmonella enterica. Poor sanitation is the main reason for the spreading of these two illnesses. When infected, they affect the whole body including the digestive tract. These two diseases can be successfully treated by timely diagnosis and proper treatments. However, they may cause complications in some patients due to poor response to treatment, delayed treatment or incorrect diagnosis.

CONTENTS

1. Overview and Key Difference
2. What is Salmonella Typhi 
3. What is Salmonella Paratyphi
4. Similarities Between Salmonella Typhi and Paratyphi
5. Side by Side Comparison – Salmonella Typhi vs Paratyphi in Tabular Form
6. Summary

What is Salmonella Typhi?

Salmonella Typhi is a serotype of the bacterial species Salmonella enterica. It is the serotype that causes typhoid fever. Typhoid fever is prevalent in areas of poor sanitation and is a major public health concern. Also, salmonella typhi is a rod-shaped gram-negative bacterium. Moreover, it is a flagellated bacterium. The bacterium resides only inside the human body.

Figure 01: Salmonella Typhi

Looking at cause of the disease, the bacterium enters the human body through ingestion of food and water contaminated with the bacterium. Once the bacterium enters the human digestive tract, it multiplies and makes more copies of bacteria. Then, they invade the blood circulation and travel into organs such as liver, spleen, bone marrow, etc. and multiply by developing the disease.

What is Salmonella Paratyphi?

Salmonella Paratyphi is another serotype of Salmonella enterica. There are three types of serovars as Paratyphi A, B, and C. Also, it is a rod-shaped gram-negative bacterium. Moreover, it possesses flagella like Salmonella Typhi.

Furthermore, Salmonella Paratyphi is responsible for paratyphoid fever. However, paratyphoid fever is less severe than typhoid fever. Also, the  bacterium creates gastrointestinal tract symptoms. But, it is a less invasive disease. Moreover, as like the Salmonella Typhi, Paratyphi also enters the human body via fecal-oral route.

What are the Similarities Between Salmonella Typhi and Paratyphi?

  • These are two pathogenic bacterial serotypes.
  • Also, both are gram-negative rod-shaped bacteria.
  • They can be found in blood, fecal matter and urine of infected people.
  • Moreover, these two serotypes are highly adapted to higher primates.
  • And, both cause enteric fever including typhoid and paratyphoid fever.
  • However, these bacteria should enter us through our mouth in order to cause the infection.
  • Furthermore, they cause illnesses that show similar symptoms.
  • Therefore, laboratory testing of a faecal, urine or blood specimen is necessary to confirm that symptoms are due to infection with Salmonella Typhi or Salmonella Paratyphi.
  • Besides, both bacteria can cause life-threatening diseases if proper treatments are not done.
  • But, these bacteria can be controlled by antibiotics.

What is the Difference Between Salmonella Typhi and Paratyphi?

Salmonella Typhi is responsible for typhoid fever while Salmonella Paratyphi is responsible for paratyphoid fever. Therefore, this is the key difference between Salmonella Typhi and Paratyphi. Also, typhoid fever is a severe disease than paratyphoid fever.

Moreover, a further difference between Salmonella Typhi and Paratyphi is that the Salmonella Typhi is highly prevalent than Salmonella Paratyphi. Furthermore, there are two types of Salmonella Typhi as ST1 and ST2 while there are three types of Salmonella Paratyphi as Paratyphi A, B and C. Therefore, this is also a difference between Salmonella Typhi and Paratyphi.

Summary – Salmonella Typhi vs Paratyphi

Salmonella enteric is a bacterial species that is responsible for enteric fever. There are two types of enteric fever as typhoid fever and paratyphoid fever. Salmonella Typhi is the bacterium that causes typhoid fever while Salmonella Paratyphi is the bacterium that causes paratyphoid fever. Both diseases show similar symptoms. However, paratyphoid fever is a milder disease than typhoid fever. Thus, this summarizes the difference between Salmonella Typhi and Paratyphi.