Widal (Slide Agglutination Method)
The Widal test detects antibodies against Salmonella typhi and paratyphi, the bacteria that cause typhoid fever. A rising titre over time is more diagnostic than a single test.
6 hours
Turnaround
Blood
Sample
What the Widal (Slide Agglutination Method) test tells you
The Widal test is an old and widely available way of looking for antibodies produced against Salmonella Typhi and the paratyphoid salmonellae, the bacteria behind enteric fever. In the slide agglutination form used here, drops of serum are mixed with prepared bacterial suspensions and the technologist watches for visible clumping. Separate reactions look at antibodies against the somatic antigen of the bacterial body and the flagellar antigen of its tail, and the pattern across those reactions is what the report describes.
Typhoid itself presents as a fever that builds over days rather than arriving suddenly, often with headache, abdominal discomfort, poor appetite and a change in bowel habit in either direction. It remains an important diagnosis to consider in and after travel to regions where the infection is common. Because antibodies take time to appear, this test is generally more informative later in the illness than at its beginning, and comparing a first sample with a second one taken some days afterwards carries more weight than any single reading.
Its weaknesses are well documented and are worth stating plainly. Antibodies persist after an old infection and after typhoid vaccination, and in populations where typhoid is common a background level of antibody is widespread, so a positive reaction often reflects something other than current illness. Cross-reaction with malaria, dengue and other febrile infections, and with some liver and autoimmune conditions, adds further false positives. In the other direction, the test can be negative early in a genuine infection or when antibiotics have already been started. Blood culture, which grows the organism itself, remains the reference standard, and a Widal result is at best supportive of a diagnosis made on the whole clinical picture.
Used in the diagnosis of typhoid fever, particularly in endemic areas where blood culture facilities may be limited.
It is one of several tests considered when a fever has continued for days without an obvious cause. It contributes to the picture rather than settling it.
Where enteric fever is already suspected on symptoms and travel history, the pattern of reactions can add weight while culture is awaited.
A clear increase between an early sample and a later one is more persuasive than any single result. This is how the test is best used.
It is quick and widely accessible, which is why it is still used in settings where blood culture is not readily available.
Reasons your doctor may request the Widal (Slide Agglutination Method) test
Your doctor may order this test for any of the reasons below. Some are routine checks, others follow specific symptoms or an earlier result.
Prolonged fever
Fever continuing for several days without an obvious source, particularly with headache and abdominal discomfort.
Travel & close contacts
Fever after travel to or residence in a region where typhoid is common.
Symptoms in a household member or close contact of someone with confirmed typhoid.
Alongside culture & repeat sampling
Suspected enteric fever where blood culture has been taken and the result is awaited.
A follow-up sample requested to compare against an earlier one.
No fasting window — pick any slot that suits you, online or on WhatsApp.
A DHA-licensed nurse collects your sample at home or in the office — free home collection.
A physician-reviewed, easy-to-read report lands securely by WhatsApp and email.
Widal screens for typhoid (Salmonella) antibodies.
Widal (Slide Agglutination Method)
Widal screens for typhoid (Salmonella) antibodies.
No infection or antibodies detected — a negative result.
Detected — a positive result. Please consult your physician for confirmation and next steps.
This test is reported descriptively rather than on a numeric scale — each finding below explains what your report may say.
This information is for general education only and is not medical advice. Reference ranges can vary by laboratory, age, sex, and individual factors. Always consult your physician or doctor to interpret your results.
What a higher result can point to
- Current typhoid or paratyphoid fever, where antibody levels rise as the illness progresses.
- A past episode of enteric fever leaving antibodies that persist long after recovery.
- Previous typhoid vaccination, which produces antibodies indistinguishable from those of infection on this test.
- Background antibody carried by many healthy people in regions where typhoid is common.
- Cross-reaction with other febrile illnesses such as malaria and dengue.
- Some chronic liver conditions and autoimmune disorders that provoke non-specific reactions.
These are possibilities, not diagnoses. A single value outside the reference range is interpreted alongside your symptoms, history and other tests — your doctor decides what it means for you.
What this test cannot tell you
- The test has well-documented specificity problems: previous typhoid vaccination, an old infection, and background antibody in populations where typhoid is common all produce misleading positive results.
- Cross-reaction with malaria, dengue and other febrile infections is common, so a positive reaction is not specific to typhoid.
- It can be negative early in a genuine infection, before antibodies have developed, and in people who have already started antibiotics.
- Blood culture remains the reference standard for diagnosing typhoid, and results from different laboratories and kits are not directly comparable.
Risks of the blood draw
- Mild bruising or brief soreness where the needle went in.
- Occasional lightheadedness, which settles after a few minutes of rest.
- Bleeding or infection at the site, which is rare with sterile single-use equipment.
- 1The test detects antibodies against typhoid and paratyphoid bacteria, not the bacteria themselves.
- 2Blood culture is the reference standard, and this test is supportive at best.
- 3Vaccination, past infection and background exposure in endemic areas all cause positive results without current illness.
- 4A negative result early in the illness or after antibiotics have been started does not rule typhoid out.
- 5Paired samples showing a clear rise are far more informative than a single reading.
Frequently Asked Questions
Everything you need to know about the Widal (Slide Agglutination Method) test. Can't find what you're looking for?
Talk to our team→No. It is a supportive test with well-known accuracy problems in both directions. A diagnosis rests on your symptoms, examination and travel history, ideally confirmed by blood culture, which grows the organism itself.
Antibodies build up as the illness progresses, so a clear rise between an early sample and a later one is far more convincing than a single reading. It helps separate a current infection from antibodies left over from the past.
It can be, and this is one of the test's real weaknesses. The antibodies produced by vaccination cannot be distinguished from those produced by infection on this method, so always tell your doctor about any typhoid vaccination you have had.
Yes. Malaria, dengue and several other fevers, along with some chronic liver and autoimmune conditions, can cause cross-reactions. This is why the result is never interpreted on its own and why culture matters when it is available.
The Widal test detects antibodies against Salmonella typhi and paratyphi, the bacteria that cause typhoid fever. A rising titre over time is more diagnostic than a single test.
Used in the diagnosis of typhoid fever, particularly in endemic areas where blood culture facilities may be limited.
No, fasting is not required for the Typhoid Screen (Widal) test, so you can eat and drink normally beforehand.
The Typhoid Screen (Widal) test uses a blood sample, collected quickly by our DHA-licensed phlebotomist with minimal discomfort.
Results for the Typhoid Screen (Widal) test are typically ready within 6 hours. You will receive a secure digital report, and your Smart Report highlights anything outside the normal range.
The Typhoid Screen (Widal) test is AED 70, which includes free home sample collection and a physician-reviewed report. You can also build a custom panel and pay only for the markers you choose.
Yes. A DHA-licensed phlebotomist can collect your sample at home or the office anywhere in Dubai at no extra cost, 7 days a week. See how it works.
It is commonly chosen by all ages. If you are not sure it is right for you, our care team is happy to advise.
Add the Typhoid Screen (Widal) test to your cart and complete the short booking wizard, choosing home collection or a lab visit. Guest checkout lets you book without creating an account.
Yes. It is processed at our EIAC-accredited laboratory (ISO 15189:2022) under DHA license 0046381 and verified by board-certified pathologists.
Every report includes reference ranges and plain-language notes. If you have questions, our care team can arrange a clinician review — just get in touch.
Absolutely. Add it to a curated health package or bundle it with any of our 160+ biomarkers, often from a single sample in one visit.