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Panbio Dengue ELISAs
Most appropriate use: Panbio
Dengue ELISAs
Panbio Dengue ELISAs
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Dengue IgM Capture ELISA (E-DEN01M)
– For the diagnosis of active dengue
– Suitable for use in endemic and non-endemic dengue regions
– Recommended for use with the Dengue IgG Capture ELISA in
regions where secondary dengue is prevalent
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Dengue IgG Capture ELISA (E-DEN02G)
– For the diagnosis of secondary dengue
– For use in dengue endemic regions
– Use with the Dengue IgM Capture ELISA to detect and distinguish
primary and secondary dengue with a high degree of confidence
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Dengue Duo IgM and IgG ELISA (E-DEN01D)
– This kit consists of the Dengue IgM Capture ELISA and the Dengue
IgG Capture ELISA packaged together for convenience and cost
savings.
– Ideal for use in regions where primary and secondary dengue are
common.
– For the differentiation of primary and secondary dengue.
Panbio Dengue ELISAs cont.
• Dengue IgG Indirect ELISA (E-DEN01G)
– For detecting past or active dengue
– Suitable for seroepidemiological studies
Positioning
• Laboratory testing
• Recommend test based on location and patient types
– i.e. endemic region v non-endemic region
– Is differentiation between primary and secondary important?
– Diagnosis of infection v seroepidemiological screening
• Emphasize Panbio: No 1 in dengue fever detection
– Numerous publications to support this
Panbio Dengue IgG Indirect ELISA
Specific serum antibodies combine with dengue 1-4
antigens attached to the polystyrene
surface of the microwells
Washing removes residual serum
Peroxidase-conjugated anti-human specific
immunoglobulin is added
The colourless substrate,
tetramethylbenzidine/hydrogen peroxide (TMB /
H2O2) is hydrolysed to a blue chromogen
Stopping the hydrolytic reaction
with acid turns the TMB yellow
Colour development indicates the presence
dengue antibodies in the test sample
Dengue IgG Indirect ELISA
Anti-human IgG HRP conjugated
Patient’s dengue specific IgG
Dengue antigen coated plate
Panbio Dengue IgM & IgG Capture ELISAs
Dengue IgM Capture ELISA
Dengue antigen-Mab complex
IgM in patient’s serum
Anti-human IgM coated plate
Dengue IgG Capture ELISA is essentially the same except anti-human IgG antibodies
are coated on the plate and therefore IgG in the patient’s serum is captured.
Interpretation: Capture ELISAs
IgM positive / IgG negative
• Serology indicates the probability that the patient has
current or recent primary dengue infection.
IgM positive / IgG positive
• Serology indicates the probability that the patient has
current or recent secondary dengue infection.
IgM negative (equivocal) / IgG positive
• Serology indicates the probability that the patient has
current or recent secondary dengue infection.
– In secondary dengue IgM may be negative in up to 75% of patients,
depending on the stage of disease when the sample was collected.
Interpretation cont: Capture
ELISAs
IgM equivocal / IgG negative
• Serology indicates that the patient may have current or
recent primary dengue infection.
– If clinical signs and symptoms persist recommend that a second
serum sample be collected and tested.
IgM positive / IgG equivocal
• Serology indicates the probability that the patient has
current or recent primary dengue infection.
– Equivocal IgG suggests that the patient may have current or recent
secondary dengue infection.
– Patient should be monitored.
– If clinical signs and symptoms persist recommend that a second
serum sample be collected and tested.
Interpretation cont: Capture
ELISAs
IgM negative / IgG negative
• Serology indicates the probability that the patient does
not have current or recent dengue infection.
– Note: Serum samples collected early in infection may yield
a negative serological test result.
– If a differential diagnosis can not be established and clinical
signs and symptoms persist, recommend that a second
serum be collected and tested.
IgM negative / IgG equivocal
• Equivocal IgG suggests that the patient may have
current or recent secondary dengue infection.
– Patient should be monitored.
– If clinical signs and symptoms persist recommend that a
second serum sample be collected and tested.
Interpretation cont: Capture
ELISAs
IgM positive / IgG positive
• Suggestive of an active dengue infection. Could be
either primary or secondary. Use the Dengue IgG
Capture ELISA if distinction between primary and
secondary dengue is necessary.
IgM negative / IgG positive
• Suggestive of a past infection. Secondary dengue
infection cannot be ruled out as IgM levels in
secondary dengue may be undetectable. If the
patients IgG result is >40 Panbio Units, it is likely that
the patient has a secondary infection.
Performance: Capture ELISAs
Serological sensitivity and specificitya
High sensitivity
High specificity
Some patients exhibit no IgM in a secondary infection. Therefore
detection of high IgG levels to improve the sensitivity is recommended
Performance: IgM Capture ELISA
Cross reactivity study
94.8% specificity
Performance: IgG Capture ELISA
Cross reactivity study
96.8% specificity
Publications: Panbio Dengue
ELISAs
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Vaughn et al (1999). Rapid serological diagnosis of dengue virus
infection using a commercial capture ELISA that distinguishes primary
and secondary dengue infections. Am.J.Trop.Med.Hyg., 60:693-698.
Lam & Devine (1998). Evaluation of capture ELISA and rapid
immunochromatographic test for the determination of IgM and IgG
antibodies produced during dengue infection. Clin.Diagn.Virol. 10:75-81.
Chew et al. (1998). Evaluation of commercial capture ELISA for
detection of immunoglobulin M and G antibodies produced during
dengue infection. Clin.Diagn.Lab.Immunol. 5:7-10.
Cuzzubbo et al. (1997). Commercial assays for the serological
diagnosis of dengue infection. In Arbovirus Research in Australia 7:5660.
Phillips et al. (1997). Flavivirus diagnostic assays: the Queensland
perspective. In Arbovirus Research in Australia 7:208-211.
Cuzzubbo et al. (1998). Detection of specific antibodies in saliva during
dengue infection. J. Clin. Microbiol. 36:3737-3739.
Allwin et al. (1998). Abstract. Assessment of flavivirus-specific antibody
cross-reactivity after vaccination against TBE and yellow fever. Eur.
Conf. Clin. Vir., Hamburg.
Available upon request
Commonly Asked Questions about
Panbio dengue tests...
Q In the Panbio Dengue Duo ELISA and Dengue Rapid
Tests, why don’t symptomatic donors from endemic
areas show elevation of IgG?
A IgG Cutoff set above the level in Primary and Past
Dengue.
Commonly Asked Questions about
Panbio dengue tests...
Q How do the cutoffs of these tests compare with
haemagglutination-inhibition assays?
A IgG Cutoff = HAI Titre for 2° Dengue (e.g. HAI 1:2560).
Commonly Asked Questions about
Panbio dengue tests...
Q Do I need to use both IgM and IgG for the diagnosis of
dengue infection? Why can’t I just use IgM?
A Some cases of secondary dengue do not show
detectable IgM.
References
1. Dengue IgM Capture ELISA Instructions for Use. Rev
08/12/04
2. Dengue IgG Capture ELISA Instructions for Use. Rev
20/10/03
Panbio Dengue: The complete
range
ELISA kits
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Dengue IgG Indirect
Dengue IgM Capture
Dengue IgG Capture
Dengue Duo Capture IgG & IgM
E-DEN01G
E-DEN01M
E-DEN02G
E-DEN01D
Rapid kits
• Dengue Rapid Strip test
• Dengue Rapid Cassette
R-DEN02D
R-DEN03D
www.panbio.com