Salmonella widal test: Indications, meaning

The Salmonella Widal test (or Widal test) is considered the standard for diagnosing typhoid. Since then, the Widal test has been used to screen for typhoid in the community and assist in the treatment and monitoring of this disease. The purpose of this test is to detect anti-Salmonella O and H antibodies in serum.

To understand this test we need to understand what salmonella is?
This is a gram-negative bacillus causing typhoid - an acute infectious disease, caused by strains of S.typhi, S.paratyphi A, S.paratyphi B and S.paratyphi C.
Clinical manifestations of the disease include systemic lesions accompanied by pathological lesions, typically gastrointestinal diseases. The antigenic structure of this bacterium includes: O-antigen and H-hair antigen.
Salmonella Widal test is a type of test that works based on a specific antigen-antibody agglutination reaction mechanism. Through this mechanism, the test can detect anti-Salmonella O and H antibodies in the serum of people with typhoid fever. The reaction appeared on 3 strains of bacteria: S. typhi (H), S. paratyphi A (AH) and B (BH). To perform this test, patients need to perform 2 times, the 1st time is done at the end of the first week and the 2nd time is done 7 to 14 days apart from the 1st time.

This is a test that detects antibodies in salmonella bacteria. Widal testing can be performed in a test tube or on a sheet of paper. After taking this test, if you receive a negative result, it means that your body has never been infected with Salmonella bacteria. But in case the result is positive, it means that you are infected or have been infected with typhoid. Therefore, you should visit your doctor for detailed advice about this disease. Your doctor will check to see if you have any symptoms of typhoid fever, for example: Diarrhea, fever, abdominal cramps, etc. If necessary, your doctor may order you to do some tests. specific as blood culture, stool culture for Salmonella.

When the patient has typhoid fever, the disease has diverse and non-specific symptoms, often difficult to distinguish from other febrile illnesses clinically. The cause of the disease is Salmonella Typhi (S. Typhi), which can cause a systemic infection.
Risk factors for disease are often due to unsafe water, eating dirty food or hygiene habits of sick people. Therefore, typhoid has similar characteristics to cholera, diarrhea, ... In addition, the patient has a high risk of contracting a number of other diseases. The onset of the disease is often accompanied by sudden fever, headache, abdominal pain and diarrhea. If not treated promptly, the disease can progress at a rapid rate and can progress to a variety of complications such as gastrointestinal bleeding, intestinal perforation, and even death.
Salmonella bacteria currently have an increasing rate of drug resistance, which makes treatment difficult. Therefore, it is very important to vaccinate high-risk groups. Because the symptoms of the disease are very diverse, people choose the Salmonella Widal test for early diagnosis instead of using blood cultures or other cultures that are time-consuming.
Indication of testing for the following subjects:
People infected with Salmonella in the first stage (from the second week, do 2 times a week apart to find antibody dynamics). This has the effect of monitoring and supporting the treatment of the disease. For people living in endemic areas. In the absence of facilities for performing cultures, the Salmonella Widal test is highly reliable and diagnostic in this case. Vinmec International General Hospital is one of the hospitals that not only ensures professional quality with a team of leading medical professionals, a system of modern equipment and technology. The hospital provides comprehensive and professional medical examination, consultation and treatment services, with a civilized, polite, safe and sterile medical examination and treatment space. Customers when choosing to perform tests here can be completely assured of the accuracy of test results.