Salmonellosis Salmonella

What is Salmonellosis?

Salmonellosis is an acute infectious gastro-intestinal disease caused by a large group of bacteria known as salmonella. There are over 2,000 types of salmonella with considerable variability from country to country and region to region.

How do you get Salmonellosis?

You can get salmonella by consuming improperly prepared, contaminated food. Because salmonella bacteria are ubiquitous, they can be found in many contaminated foods and food products.  Unpasteurized milk and all kinds of milk products made with unpasteurized milk may be contaminated with salmonella.  Other common sources include raw or poorly cooked eggs or egg products and raw or poorly cooked meat and meat products, especially poultry and poultry products.

In spite of treatment, an infected person can spread the bacteria for several days to weeks without any symptoms.  Other infected people may develop a so-called “carrier state” in which they can spread the bacteria for many months.  A very small number of people may excrete the bacteria for more than a year.

Susceptibility and Resistance

Everyone is susceptible to salmonella poisoning.

Incubation Period

The incubation period for Salmonellosis is 1-3 days.

What are the Symptoms?

Salmonella begins with a headache, pain in the abdomen, diarrhoea, nausea and vomiting.  Fever is almost always present.  Dehydration may occur rapidly, especially in the young and elderly.  The illness continues for several days and may vary from relatively mild to severe symptoms.  Occasionally, the bacteria gain access to the blood stream and cause a serious illness.  Deaths are relatively rare, except in the very young and elderly. 

Preventative Measures

Prevention of this infection involves avoiding contaminated water and improperly cooked meats, poultry, eggs, etc.  Careful hygiene with frequent hand washing is also recommended.


There is no vaccine against salmonella.  For intestinal infections, supportive treatment to maintain adequate hydration (good fluid intake) is generally all that is required.  For salmonella that spreads beyond the intestines, e.g., into the blood stream, antibiotic treatment is required.  Resistance to commonly used antibiotics is variable around the world.


Where Does It Commonly Occur?

With over 2,000 known types of salmonella bacteria, this group of bacteria occur worldwide with many variations from country to country and region to region.