Understanding Widal Test - Salmonella Paratyphi B (H): Normal vs Optimal Ranges
Also known as: paratyphoid b h antigen, s. paratyphi b flagellar antigen, widal paratyphi b h
?What is Widal Test - Salmonella Paratyphi B (H)?
The Widal test measures antibodies against Salmonella paratyphi B flagellar (H) antigen, which is used to aid in the diagnosis of paratyphoid fever. This serological test detects either IgM (acute infection) or IgG (past or chronic infection) antibodies. Paratyphoid fever is caused by Salmonella paratyphi bacteria and presents similarly to typhoid fever.
!Why It Matters
A positive result for Salmonella paratyphi B H antibody may suggest current or recent paratyphoid B infection, particularly when combined with clinical symptoms and other Widal test components. This marker helps healthcare providers identify bacterial infections requiring prompt treatment and public health monitoring. Results should always be interpreted alongside clinical presentation, O antigen results, and other diagnostic findings rather than as a standalone indicator.
Reference Ranges
| Range Type | Min | Max | Unit | Note |
|---|---|---|---|---|
| Lab Normal | — | — | Titer | Standard lab reference range |
| Optimal | — | — | Titer | Evidence-based optimal range for health |
| Longevity Target | — | — | Titer | Per longevity medicine research (Attia et al.) |
Lab normal ranges may vary between laboratories. Optimal and longevity targets are based on research literature and should be interpreted with your physician.
Symptoms of Imbalance
- Prolonged fever lasting 1–3 weeks
- Abdominal pain and discomfort
- Headache and general malaise
- Diarrhea or constipation
- Rash on trunk (rose spots)
How to Improve Your Levels
- 1Follow prescribed antibiotic therapy as directed by a healthcare provider
- 2Ensure complete rest and adequate hydration during acute infection
- 3Maintain proper food and water hygiene to prevent reinfection
- 4Avoid food preparation for others during acute illness to prevent transmission
- 5Monitor symptoms closely and report complications to a physician
- 6Complete the full course of antibiotics even after symptom improvement
When to Test
The Widal test should be considered when a patient presents with prolonged fever, abdominal symptoms, and clinical suspicion of enteric fever. Testing is most reliable from the second week of illness onward when antibody titers are higher. It is particularly relevant in endemic regions or in individuals with recent travel history to areas with high paratyphoid prevalence.
Related Biomarkers
Track your Widal Test - Salmonella Paratyphi B (H) with ByoMap
Upload your blood report and get personalized Widal Test - Salmonella Paratyphi B (H) ranges based on your age, sex, and ancestry — free.
Try Free — Upload Your Report