onsite typhoid igg/igm rapid test simplifying diagnostics of s. typhi & paratyphi infection
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OnSite Typhoid IgG/IgM Rapid TestSimplifying Diagnostics of S. typhi & paratyphi Infection
Contents S. typhi and paratyphi infection Current detection methods OnSite Typhi IgG/IgM Rapid Test To be aware of
S. typhi and paratyphi Infection
• Gram negative
• Facultative rod-shaped bacterium
• Enterobacteriaceae family
S. Typhi and Paratyphi Type A, B, C
Structure of Typhi Bacterium
• O and H antigen are the most predominant antigens which induce antibody production during infection
• IgM to O antigen is seen in primary infection and re-infection • H antigen is a strong IgG immunogen
Flagellar “H” antigen
Somatic “O” antigen
S. Typhi & Paratyphi Transmission
Contaminated food or water
• Raw food
• Poor water sanitation
• Traditional sanitary style
• Inappropriate food & water preparation or storage
Traveler disease!
High Prevalence of Typhi and Paratyphi in Developing Countries
In 2000, Typhi and Paratyphi cause
• Over 2.16 million episodes worldwide
• 216,000 deaths
• More than 90% occurred in Asia
S. Typhi & Paratyphi Infection Trend
• S. Typhi infection decreases dramatically• Paratyphi infection is predominant now
Detection of both S. typhi and paratyphi are critical
Typhi & Paratyphi Fever Symptoms
• Daily increase of fatigue• Headache• Diarrhea• Malaise• Anorexia• Transient macular rash of rose-colored
spots on body trunk• Daily increase in fever of 38.5 to ℃
40 by the 3℃ rd or 4th day of illness• Constipation or diarrhea• Enlarged lymph nodes, spleen and liver
To Be Differentiated from
Present with similar symptoms (diarrhea, vomiting, fever, nausea or share similar transmission route (contaminated water source): • Malaria • Norovirus • Cholera • Influenza • Filariasis • Rotavirus • Leptospirosis• Dengue fever
Disease Course
• 6-30 day incubation • Last for one month if untreated • Serious complications: - Intestinal Hemorrhage - Intestinal Perforation• Long term carrier “Typhi Mary”
Early and accurate diagnosis is critical:• Facilitate proper treatment for early recovery and prevent deaths
• Prevent spread
Current Diagnostic Methods
Current Diagnostic Methods • Culture
- Blood culture - Bone marrow culture - Stool culture
• Serological Ab Detection
- Agglutination (widal test)
- ELISA (Typhi dot)- Lateral flow chromatographic
immunoassay (OnSite rapid test)
• Molecular Dx - Not clinically practical
Typhi Ag
A 3+ day procedure. Not a screening testAntibiotic administration reduces detection rate
Culture Detection
Widal Test: the Most Over Used Test
• Add O, H, AH, BH Widal Test reagents to all of the tubes• Incubate at 37-C overnight or rock by hands for 1 minute
• A test method developed in1896• Pre-dilute specimen to a series of dilutions
Old method Prone to operator error Time consuming Require skillful technician Cross reaction A dilution series with each target O, H, AH and BH
Not recommended by WHO
Typical Problems with Widal Test
Cross reaction with non-Typhi Salmonella or malaria
Cross reactivity with other LPS of enterobacteriaceae
Operator error
False Positive False Negative Inadequate application of
bacterial antigen on test tubes or slides
Variability in preparation of commercial antigens
Operator error
Low reproduce-abilityUnreliable with less sensitivity and specificity
Typhi Dot IgM or IgG Test
Dot EIA for the detection of IgM and IgG antibodies against a specific antigen for Salmonella typhi.
One hour long, 6 test procedures
79% sensitivity and 89% specificity
Does not detect Abs to S. paratyphi
Product needs to be refrigerated
12 month shelf life only
No built-in procedure control
Limited to S. Typhi, no indication of infection stage
Tubex IgM Test
Multiple proceduresExpensiveDoes not detect Paratyphi IgMDoes not detect IgG antibodies in chronic or relapsing patient
On market in the last ten years but not popular
OnSite Typhoid IgG/IgM Rapid Test
First Choice for Screening of Typhi and Paratyphi FeverTrusted by Pathologists of 50 countries
Identify Different Stages of Infection
IgM :Develops in 5-7 days, Declines in one month IgG: Rises in 10-14 days Last for months
specimen
capillary flow
conjugating Pad Control LineTest Line1sample Pad
Detection of anti typhi IgM
Test Line2
IgGIgM
Ag
Immobilized anti human IgM
Ag Ag
Ag-gold conjugateRabbit IgG gold (control)
specimen
IgGIgM
Reagent to bind human IgG
Ag
ImmobilizedAnti rabbit IgG
Detection of anti typhi IgG
control
OnSite Rapid Test Principle
OnSite Typhoid IgG/IgM Rapid Test
Qualitatively detects and differentiates IgG & IgM to S.typhi and paratyphi in: • Serum• Plasma• whole blood
Utilizes O & H antigens that do not present in healthy individuals
OnSite Typhoid IgG/IgM Test “1-2” Easy Steps
Step 1: 1 drop of specimen
Step 2: 1 drop of sample diluent
Step 3: Read result
OnSite Typhoid IgG/IgM Rapid Test
Negative IgM Positive Invalid
No Infection Early primary Active primary, Late stage or, infection repeat infection latent infection Re-Test
Test Result Interpretation
IgG Positive IgG/IgM Positive
OnSite Typhoid IgG/IgM Test Cross Reactivity
No cross reactivity to the diseases with similar symptoms
H. Pylori Rotavirus Leptospirosis Dengue fever
Cholera Influenza Malaria Pneumonia
Clinical study for IgM Test
OnSite Typhoid IgG/IgM Rapid Test
ELISA Positive Negative Total
Positive 31 3 34
Negative 2 198 200
Total 33 201 234
Relative sensitivity: 91.2%
Relative specificity: 99%
Overall agreement: 97.9%
OnSite Typhoid IgG/IgM Rapid Test
ELISA Positive Negative Total
Positive 13 1 14
Negative 2 198 200
Total 15 199 214
Relative sensitivity: 92.9%
Relative specificity: 99%
Overall agreement: 98.5%
Clinical study for IgG
OnSite Typhoid IgG/IgM Rapid Test Performance
OnSite Typhoid IgG/IgM Rapid Test Evaluation
Country China Indonesia Madagascar Pakistan Zimbabwe
Specimens 11 Typhi 9 Paratyphi A 60 Typhi-Paratyphi 20 Suspicious
specimens 20 suspicious specimens 138 specimens
Reference test kit
Test kit Blood culture Widal test Widal test Tubex IgM test Blood culture
Result 100% Positive 69% Positive (H) 20% Positive (H) 100% Positive12 positive, 126 negative
OnSIte Typhoid IgG/IgM Rapid Test 95% Positive 88% IgG Positive 30% IgG Positive 100% positive via
extended protocol100% sensitivity 93.7% specificity
Distributed to more than 50 countries
Test Detection Procedure Test time Cost
OnSite IgG/IgM Test
IgG and IgM to S. typhi & S.paratyphi O & H antigens
2 simple procedures
15 min Low
Widal Test Antibody to S. typhi & S. paratyphi O & H antigens
Dilution,Incubation
2 min – > 18 hrs
Low
Typhi dot Test
IgM and IgG to S. typhi OMP antigen
6 procedures 60 min Low
Culture Live bacterial replication Incubation 2-3 days High
OnSite Typhiod IgG/IgM Rapid TestThe 1st choice
Widal Test vs OnSite Rapid Test Test Parameter Widal Test OnSIte Typhoid IgG/IgM Rapid Test
Principle Agglutination immunoassay Lateral flow immunoassay
Antigen used S. typhi & S.paratyphi O and H antigens S.tphi & S.paratyphi O and H antigens
Test procedure 1. Dilute specimen to a series of 8 dilutions2. Add O, H, AH, BH reagents to all of the 8 tubes3. Incubate at 37-C overnight
1. Add specimen to the test device2. Add Sample Diluent to the test device
Result reading Visually observe sediments Visually observe colored IgG or IgM band in 15 minutes
Requirement - Dedicated lab staff- Tubes, water bath or incubator
- No equipment required- Minimal training
Sensitivity - 63.2 % sensitivity to cultureCite: J. Clinical and Diagnostic Research: 6(2):
198:199, 2012- 95%-100% sensitivity to culture
Comments - Time consuming- Prone to operator error- Losing its relevance in western and European
nations- Cross reactive- Required be stored at 2-8◦C
· Fast & inexpensive- Stored in a wide range of temperatures- High reproducibility- Can use whole blood specimen
Co-relation
Widal Test Typhi O antigen 1: 40: OnSite IgM Negative Widal Test Typhi O antigen 1: 80: OnSite IgM PositiveWidal Test Paratyohi H antigen 1: 80: OnSite IgG positive Widal Test Paratyohi H antigen 1: 160: OnSite IgG positive * Study in Madacascar, 2011
OnSite: Practical Advantages- DRUQDetection Advantages Detects antibodies to S.typhi & paratyphi A , B , C Differentiates IgG from IgM in the same test device Easily accessible specimens serum, plasma, whole blood, suitable for emergency care
Result Advantages Result in 15 minutes, enabling doctor to take immediate action Highly accurate & reproducible: Performance is verified in multiple regions across the world The most reliable test on the market User Advantages Can be performed by health professionals with minimal training No equipment no electricity is required 24 month stability at a wild range of temperatureQuality Advantages Launched since 2005, millions of tests are sold in more than 50 countries Key raw materials made in house in compliance with ISO 13484 to
ensure product quality and delivery quality
Final Message to Doctors
For fast, reliable and simple screening of Typhi & Paratyphi fever
Rely On Onsite Typhoid IgG/IgM Rapid tests (R0160C, R0161C)
• #1 brand of typhi IgG/IgM rapid test• Established in 2007 • Widely accepted in over 50 countries• Passed MOH evaluation studies and
registered in many countries
Together, we grow CTK
QUALITY . INNOVATION . SIMPLICITY
To Be Aware Of
To Be Aware Of #1
• Without symptoms IgG or IgM positive = Infection or Exposure
• With symptoms IgG or IgM positive = Disease
To Be Aware Of #2
Typhi is an acute infection. It progresses rapidly. Test result at initial test is negative, but can turn to positive few days late
Re-sampling is necessary if symptoms persist
Detectable level
• Proper action to be followed – Verify by confirmatory tests to make final
diagnostic decision – Conduct antibiotic sensitivity test to select proper
antibiotic for effective treatment
To Be Aware Of #3
Together, we grow CTK
QUALITY . INNOVATION . SIMPLICITY
The Common Typhi Tests on Market Test
Parameter Blood Culture Widal Test Typhoi Dot OnSIte Typhoid IgG/IgM Rapid Test
Principle Live bacterial replication Agglutination immunoassay Enzyme Immunoassay Lateral flow immunoassay
Antigen used N/A S. typhi & S.paratyphi O and H antigens S. typhi OMP antigen S.tphi & S.paratyphi O and H
antigens
Test procedure 1. Culture blood in broth from pro-enrichment
2. Dual selection enrichment
3. Dual plating. Total 3-4 day procedure
1. Pre-dilute specimen to a series of 8 dilutions
2. Add O, H, AH, BH Widal Test reagents to all of the 8 tubes
3. Incubate at 37-C overnight
1. Add 4 drops of specimens
2. Incubate for 10 mins3. Wash4. Incubate HRP-anti
human IgG or IgM 5. Wash 6. Add TMB
1. Add specimen to the test device
2. Add Sample Diluent to the test device
Result reading Traditional or biochemical identification Visually observe sediments Visually observe IgG or
IgM color dotVisually observe colored IgG or IgM band in 15 minutes
Requirement- Incubator- Electricity- Trained personnel
- Dedicated lab staff- Tubes, water bath or
incubator- Minimal training- Refrigerator
- No equipment required- Minimal training
Comments - Gold Standard method- Not a screening test
- Time consuming- Prone to operator error- Losing its relevance in
western and European nations
- Cross reactive
- 1 hour long, 7 step test procedure
- Does not detect Paratyphi
- Test components must be stored at 2-8°C
- No built-in procedure control
· Fast & inexpensive- Can be used and stored
in a wide range of temperatures
- Detects both S. typhi & Paratyphi infections
- Detects latent or chronic infection
- High reproducibility