Widal Test for Typhoid: When and Why It’s Recommended

Typhoid fever poses a critical health issue in many developing and developed countries. Early interventions are essential for effective treatment. It begins as a fever and quickly becomes a serious illness which affects multiple organs if it is not treated promptly.

In this regard, this article will explore what the Widal test is, when it should be done and why it is relevant for curing typhoid fever.

Understanding Typhoid Fever

Typhoid fever is a chronic bacterial disease that is caused by Salmonella enterica serotype Typhi. Its transmission occurs because of eating food or drinking water that has been contaminated with the faeces of insects.

Typhoid fever is characterised by a slow onset of chronic fever, headache, abdominal pain, constipation or loose stool movements. Its symptoms are occasionally observed as rash, which goes by the name ‘rose spots’.

Severity of Typhoid Fever

The infection mainly occurs in areas with poor sanitation and less access to clean water. The Typhoid fever affects millions of individuals worldwide, and it causes most of its impact in Asia, sub-Saharan Africa, and Latin America, as gauged by global health estimates. This disease can lead to serious complications such as intestinal perforation and sepsis, if not treated promptly.

Accurate and timely diagnosis is important for the proper management of individual cases, along with controlling their outbreaks. Meanwhile, blood culture is the best way to diagnose typhoid, but it is often not available or expensive in many places.

What is the Widal Test?

Widal test is a serological diagnostic test used to measure the presence of antibodies made by the body against typhoid infection. In particular, it counts agglutinating antibodies to the O (somatic) and H (flagellar) Salmonella Typhi antigens. It may also detect antibodies to Salmonella Paratyphi A and B that can result in a similar but milder disease.

It is done by pooling the serum of the patient with standardized preparations of killed suspension of Salmonella antigens. In case the serum has antibodies against these antigens, there is a visible clumping (agglutination). This is measured as a titer, and it is the most significant dilution of a serum where agglutination can be observed.

In Which Ways is the Widal Test Available?

This test can be conducted in two ways, which are the slide agglutination and tube agglutination methods. The slide agglutination method provides fast results but has less precise results. Meanwhile, the tube agglutination method is more reliable, and it allows quantification of antibodies in humans.

These tests are affordable, easy to perform, and have become a common typhoid test in many nations.

When is the Widal Test Recommended?

The Widal test is the most useful method when other diagnostic options are limited or unavailable. It is usually advised to take at least 7 to 10 days of sickness before it can be administered because the antibodies can only be detected after the first week of a fever. Testing too early can result in a false negative due to insufficient antibody production.

In regions where typhoid fever is becoming endemic, the Widal test is often used as a primary diagnosis for patients who have prolonged fever or gastrointestinal symptoms. However, clinicians are advised to interpret the results with the patient’s clinical history and local epidemiological patterns.

For example, when doctors suspect typhoid, they often examine the antibody levels in the blood. If they take two blood samples within 10 days, then it might be a stronger sign of active typhoid infection.

Why is the Widal test mostly preferred?

The rationale for using the Widal test in the diagnosis of typhoid includes multiple aspects, which are:

• Affordability: This test is affordable in comparison to blood cultures or molecular tests. It is widely accessible in the healthcare systems.
• Ease of Use: The Widal test is a simple laboratory test and needs little training, which in turn can be done in the peripheral health centres that do not have high-quality facilities.
• Availability: The test kits are easily accessible and are available in large quantities in most regions of the world. This adds to the convenience of its diagnostic usefulness in remote regions as well.

However, the Widal test’s accuracy can be affected by previous vaccinations, past infections, and the presence of other febrile illnesses that cause cross-reacting antibodies.

Steps to Improve Diagnostic Accuracy in Typhoid Testing

In order to improve the efficiency of the Widal test, there are four key steps you have to follow. These steps are discussed below:

Tell your doctor everything about your illness

Share full details about your symptoms and medical history. Tell your doctor when your fever started, if you have recently travelled in locations where typhoid is common, or if you have taken the typhoid vaccine. This helps the doctor to interpret your test results correctly.

Understand when the test works best

Consult your doctor between 7 and 10 days after fever. In this period, your body most of the time has created detectable levels of antibodies.

Be open to giving more than one blood sample

In some cases, doctors may recommend that you take two blood samples. Comparing these can show if antibody levels are rising.

By staying informed and working closely with your doctor, you can help them make sure your typhoid test details are accurate and get back to them as quickly as possible.

Conclusion

The Widal test continues to play a crucial role in diagnosing typhoid fever. Its affordability and simplicity make this test a valuable tool when interpreted correctly. If you or your loved ones are experiencing symptoms of typhoid, then choosing a trusted diagnostic centre becomes important. In this aspect, Vijaya Diagnostics is known for its reliable testing services and commitment to quality.

You can easily check the Vijaya Diagnostics test price list online or at their nearest centre to make an ideal choice for healthcare assistance.  You can browse various diagnostic tests, along with the initial cost of each treatment. You can even book your checkup appointment directly from their website.