Typhoid and Paratyphoid Enteric Fevers - Major Diseases 

Four major disease manifestations are produced by Salmonella infection

Where there are no manifestation but a person carries the bacteria and spreads around.

Enteric Fever

1) What causes Enteric fever?

Enteric fever can be caused by any of the bacterial strains of

• salmonella
• Salmonella typhi
• Salmonella paratyphi A
• Salmonella paratyphi B
• Salmonella paratyphi C

2) How does Salmonella infection causes disease in enteric fever?

After entering the small intestine wall, the Salmonella invades through the lymphatic system to the lymph nodes and after a period of multiplication invades the blood stream. From blood stream the bacteria invades the Liver, gall bladder, spleen, kidney and bone marrow where it multiplies and causes infection of these organs.

From here they again invade the blood stream causing secondary bacteremia.

The secondary bacteremia is responsible for causing fever and clinical illness.

3) What are the symptoms of enteric fever?

• Severe headache
• Fever
• Chills
• Dry cough
• Rose spots or Rashes appearing on the lower chest and abdomen
• Abdominal tenderness
• diarrhea
• bloody stools
• Anorexia (Loss of appetite)
• Malaise (General discomfort)
• Fatigue
• Weakness
• Epistaxis (Nosebleed)
• Fluctuating mood

4) What are the complications of enteric fever?

Intestinal hemorrhage (Profuse bleeding from the intestine)

Intestinal perforation and leakage of intestinal juices in to the abdomen leading to peritonitis.

Salmonella Gastroenteritis

Ingestion of food contaminated with Salmonella leads to Bacterial food poisoning causing Gastroenteritis

Salmonella are common causes of food poisoning world wide

Symptoms of Salmonella gastroenteritis -

• Watery, green offensive loose
• stools
• Vomiting
• Fever
• Shivering
• Abdominal pain
• Dehydration
• Cramps
• Renal kidney failure

Severe Salmonella infection occurs mostly in young, elderly and immuno-compromised individuals.

Bacteremia with Metastatic Disease

Bacteremia is common infection with Salmonella infection.

Due to bacteremia, Salmonella is present throughout the body resulting in persistent infection and spread of infection to many organs in the body.

Spread of bacteria is caused by Salmonella bacteremia which can lead to -

Atherosclerotic plaques within large arteries

Damaged heart valves

Joint prostheses

Osteomyelitis Arthritis

Salmonella meningitis

Asymptomatic Carriers

Even after a complete clinical cure from salmonella infection, some people continue to harbor the bacilli for long periods.

Due to the 'carrier status' of these individuals, the pathogens continue to be secreted in their faces for days or even weeks. Despite being relieved of their symptoms, this makes it possible for 'the carriers' to transmit the disease to others.