Question

Widal test is prescribed to diagnose
A. Typhoid
B. Pneumonia
C. Malaria
D. Filaria

Answer 1

Hint: Widal test is a serological test for enteric fever. It was invented by Georges-Fernand Widal in 1896. It can only give the correct result when the specific antibody level is high generally after 7-14 days.

Complete step by step answer:
To solve the question we must know about the Widal test.
Widal test is a serological test which uses the method of indirect agglutination. In this the bacteria causing fever is mixed with the serum containing specific antibodies. It is used for diagnosing enteric fever like typhoid.
Typhoid is a bacterial infectious disease which can spread through contaminated food and water. The symptoms of this disease are high fever, vomiting, and rashes in the body.
In the first week- Body temperature rises slowly and fever fluctuations are seen.
In the second week- Tiredness and high fever is seen in patients. In the third week- Very high fever, low platelet count, respiratory symptoms can be seen.
The disease can be diagnosed by Widal test by taking blood or fecal samples. The test is usually negative in the first week or during the first stage.
Pneumonia- Blood test is done to check the bacterial infection and Chest X-ray to see the spread.
Malaria—It is diagnosed by staining the blood sample with Giemsa stain and diagnosing under a microscope.
Filaria- It is diagnosed by identification of microfilariae in the blood smear under microscope.

Thus the correct answer is (A). Widal test is used to diagnose typhoid.

Note:
Widal test is an agglutination test that detects the antibodies in the blood sample against antigens. Agglutination is the visible clumps obtained due to antigen-antibody reaction.