Should You Do a Widal Test?

The Widal Test is a blood test commonly used (particularly in Nigeria) to determine if a person has typhoid fever. It checks for antibodies that fight Salmonella typhi, the bacterium that causes typhoid fever.

Before you do a widal test, you may want to consider the following:

• The test cannot distinguish between current and previous infections. This means that a person with a previous typhoid infection may continue to test Widal positive even in the absence of a new infection.
• A person vaccinated against Salmonella typhi develops antibodies against the infection, which means they will likely have a positive Widal test result.
• Other infections can cause a Widal test to come back positive. For example, typhus, malaria, liver disease, kidney disease, etc.

Hence, the reliability of a Widal test is significantly circumstantial. Before conducting one, it is important to consider factors such as previous infection, a typhoid vaccination, and other febrile conditions.