Dengue Virus Serology

Testing

Focus Diagnostics has been a leader in the development of infectious disease

immunology assays for more than 25 years. Our Dengue DxSelect™ and Dengue

Dx™ Rapid tests reflect the tradition of quality, reliability and consistency expected

by our customers around the world.

Dengue fever (DF) is the most prevalent mosquito-borne viral illness in the world –

endemic in more than 100 countries, with 2.5 billion people at risk for transmission.

The CDC estimates that there are 50 to 100 million cases of DF and several

hundred thousand cases of dengue hemorrhagic fever (DHF), causing more than

25,000 deaths annually. DF and DHF are most prevalent in tropical and subtropical

areas where there is limited public health infrastructure for mosquito control: Africa,

Asia, Mexico, and Central and South America.

40% of the world’s population is at risk of dengue infection

Dengue viruses are comprised of four closely related serotypes: DEN-1,

DEN-2, DEN-3, and DEN-4. Infection with one serotype does not provide

protective immunity to the others, and a secondary infection is more likely

to result in dengue hemorrhagic fever (DHF).

The onset of dengue symptoms is marked by the presence of dengue NS1

antigen in the patient’s serum. NS1 is a glycoprotein that is common to all

dengue serotypes and can be used to detect either primary or secondary

infections in the earliest stages. Serology testing for dengue virus-specific

antibodies, types IgG and IgM, can be useful in confirming primary or

secondary diagnosis. IgM is produced approximately 5 days after infection in

both primary and secondary infections, while IgG is produced about 2 to 4

weeks after onset of primary infection and almost immediately after onset of a

secondary infection.

Dengue Serology Testing

Dengue is spread by the

Aedes aegypti mosquito,

a day-biting mosquito that

prefers to feed on humans

and breeds in standing

water.

In Asia, dengue is spread

from the Aedes albopictus,

which has similar breeding

and feeding habits to the

Aedes aegypti mosquito.

Dengue Virus Serology Testing

The Dengue DxSelect™ IgM Capture and IgG ELISA kits are designed for optimal performance and

cost efficiency. Each kit utilizes inactivated dengue virus types 1-4 and contains 96 breakaway wells

to give laboratories the flexibility to set up runs based on volume requirements, improve turnaround

time with reduced incubation requirements, and eliminate sample pre-treatment.

Dengue Virus IgG and IgM Capture DxSelect™ ELISA Kits

Sensitivity and specificity for the Dengue Virus IgG DxSelect™ ELISA kit was assessed through well

characterized sera. This sera was drawn from patients exhibiting dengue fever (DF) or dengue hemorrhagic

fever (DHF) symptoms within 1 to 16 days of onset and were previously confirmed as infected with dengue

virus by ELISA, hemagglutination inhibition (HI), and/or PCR.

Dengue Virus IgG DxSelect™ Performance Summary

Condition Sensitivity 95% CI

DF 98% (49/50) 89.4 - 99.9%

DHF 93% (27/29) 77.2 - 99.2%

Overall 96% (76/79) 89.3 - 99.2%

Dengue Virus IgG DxSelect™ ELISA SensitivityCondition Specificity 95% CI

Overall 93% (253/271) 89.7 - 96.0%

Dengue Virus IgG DxSelect™ ELISA Specificity

Sensitivity and specificity for the Dengue Virus IgM Capture DxSelect™ ELISA kit was assessed through well

characterized sera. This sera was drawn from patients exhibiting dengue fever (DF) or dengue hemorrhagic

fever (DHF) symptoms within 1 to 16 days of onset and were previously confirmed as infected with dengue

virus by ELISA, hemagglutination inhibition (HI), and/or PCR.

Dengue Virus IgM Capture DxSelect™ Performance Summary

Condition Sensitivity 95% CI

DF 96% (48/50) 86.3 - 99.5%

DHF 96% (25/26) 80.4 - 99.9%

Overall 96% (73/76) 88.9 - 99.9%

Dengue IgM Capture DxSelect™ ELISA Sensitivity

Condition Specificity 95% CI

Overall 97% (296/306) 94.1 - 98.4%

Dengue IgM Capture DxSelect™ ELISA Specificity

Condition Sensitivity 95% CI

Low IgM 97% (29/30) 82.8 - 99.9%

Primary Infection 100% (10/10) 69.2 - 100%

Secondary Infection 90% (9/10) 55.5 - 99.8%

Old Infection 7% (1/14) 0.2 - 33.9%

Overall excluding Old Infection 96% (48/50) 86.3 - 99.5%

Overall 77% (49/64) 64.3 - 86.2%

Dengue IgM Capture DxSelect™ ELISA Sensitivity With Primary, Secondary, and Old Infection Sera*

*The overnight incubation method was used to perform the assay.

Dengue Virus Serology Testing

A positive result will not change once it has been established within 15-20 minutes. In order to prevent

incorrect results, test results should not be interpreted after 20 minutes.

The Dengue Dx™ NS1 Antigen and IgG/IgM Rapid tests detect primary or secondary infections in 15

minutes using whole blood, plasma, or serum samples. These easy-to-use rapid strip tests detect all

four dengue serotypes and are practical for both point of care and laboratory testing.

Dengue Dx™ Rapid Tests

Dengue Dx™

NS1 AntigenRT-PCR and Viral Culture

SpecificityPositive Negative

POSITIVE 104 3 92.8%

NEGATIVE 8 186 98.4%

The Dengue Dx™ IgG/IgM test was compared to the hemagglutination inhibition (HI)

test and showed good correlation. Specimens used in the Dengue Dx™ NS1 Antigen

Rapid test were confirmed with Dengue RT-PCR and/or Viral Culture.

Dengue Dx™ NS1 Antigen Rapid Test

Dengue Dx™ IgG/IgM Rapid Test

Days After Onset 1-7 Days 8-14 Days All

NS1 Antigen + + – or + – or + –

IgG/IgM – / + + / – + / + + / – – / –

Interpretation Primary Infection

Secondary Infection

Primary Infection

Secondary Infection

No dengue infection

Dengue Dx™ Test Interpretation

Dengue Dx™ Performance Summary

Dengue Dx™

IgG/IgMRT-PCR and Viral Culture

SpecificityPositive Negative

POSITIVE 93 9 91.2%

NEGATIVE 20 180 90%

Dengue Virus Serology Testing

Ordering Information

Catalog Number Description Quantity

EL1500G CE Dengue Virus IgG DxSelect™ 96

EL1500M CE Dengue Virus IgM Capture DxSelect™ 96

RT1510 CE Dengue Dx™ NS1 Antigen Rapid Test 25

RT1500GM CE Dengue Dx™ IgG/IgM Rapid Test 25

Learn more about our products on our Web site: www.focusdx.com

For additional information contact Focus Diagnostics Customer Service at:

+1-562-240-6500 or fax +1-562-240-6510.

Cypress, California 90630 USA www.focusdx.com

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ISO 13485:2003 Certified QUALITY MANAGEMENT SYSTEM

LITERATURE FOR DISTRIBUTION OUTSIDE THE USA ONLY

Focus Diagnostics, the associated logo and DxSelect are the trademarks of Focus Diagnostics.

IgM antibodies appear approximately 5 days after the onset of symptoms, followed by IgG at about 14 days post-onset. IgM levels peak after 1 to 2 weeks, but may be elevated for 2 to 3 months after illness.

Primary Infection

Dengue DxSelect™ and Dengue Dx™ Kits Detect All Stages of Infection

IgG rises rapidly within 1 to 2 days of symptoms and often exceeds previous levels; IgM may not appear for up to 20 days and may be undetectable in 20-30% of secondary infections.

Secondary Infection

Primary Infection

Onset of symptomsOnset of symptoms

IgG

Secondary Infection

Ant

igen

& A

ntib

ody

Leve

l

NS1 Ag NS1 Ag

IgMIgM

IgG

Dengue Virus Serology Testing

Common to all dengue serotypes and can be used to detect either primary or secondary infections.

NS1 Antigen