Simplexa® Flu A/B & RSV Direct Gen II Kit

Latest generation assay with comprehensive strain coverage that can be run with the Simplexa® COVID-19 Direct Assay to differentiate Flu A, Flu B, RSV and SARS-CoV-2.

KIT for Infectious Diseases



Influenza (flu) is a contagious respiratory illness caused by influenza viruses. It can cause mild to severe illness. Serious outcomes of flu infection can result in hospitalization or death. Older people, young children, and people with certain existing maladies, are at high risk of serious flu complications. There are two main types of flu virus: Types A and B.

Influenza A viruses are the only influenza viruses known to cause flu pandemics.1 A pandemic can occur when a new and very different influenza A virus emerges that both infects people and has the ability to spread efficiently between people. While there are potentially 198 different influenza A subtype combinations, only 131 subtypes have been detected in nature.1 Current subtypes of influenza A viruses that routinely circulate in people include: A(H1N1) and A(H3N2).1

Influenza B viruses are not divided into subtypes, rather they are further classified into two lineages: B/Yamagata and B/Victoria.1 Influenza B viruses generally change more slowly in terms of their genetic and antigenic properties than influenza A viruses and therefore typically have a slower circulation.2 However, the proportion of influenza B viruses that circulate can vary by geographic location.

RSV is a contagious illness that infects the respiratory tract and can lead to more severe infections like pneumonia or bronchiolitis. In older children, RSV can resemble a bad cold, but in babies it’s sometimes a serious illness — particularly for those with other medical conditions such as asthma, or those who were born prematurely. RSV infections can also be dangerous for certain adults. Adults at highest risk for severe RSV infection include those 65 years and older, those with chronic heart or lung disease and those with compromised immune systems.

1. Centers for Disease Control and Prevention. (n.d.). Types of Influenza Viruses. Retrieved from

2. Centers for Disease Control and Prevention. (n.d.). Antigenic Characterizations. Retrieved from

Why to choose it

A CLIA moderate complexity assay with the most comprehensive strain coverage (over 100 strains) that ensures high performance and provides improved efficiency with a true sample-to-answer workflow without RNA extraction. The Simplexa® Flu A/B & RSV Direct Gen II assay and the Simplexa® COVID-19 Direct assay can be run on the same disc at the same time for differential diagnosis of SARS-CoV-2, Flu A, Flu B and RSV. Alternatively, the assay can be run as a stand alone test based on your specific diagnostic needs.


100+ strains

DiaSorin Molecular continually monitors the major flu databases and tests newly emerging and vaccine flu strains on an ongoing basis.

100+ strains

We have collectively tested over 100 Flu A, B & RSV strains to ensure confidence in assay performance.

2020/2021 Northern Hemisphere
A/Hawaii/70/2019 (H1N1)T
A/Hong Kong/2671/2019V
2020/2021 Southern Hemisphere
A/Brisbane/02/2018 (H1N1)V
A/South Australia/34/2019 (H3N2)T
V = Validated and in CE marked IFU
T = Tested in silico but not in IFU

Flexibility for your lab

With the LIAISON® MDX system, the Simplexa® COVID-19 Direct assay and the Simplexa® Flu A/B & RSV Direct Gen II assay can be run on the same disc at the same time for differential diagnosis of COVID-19 and flu from one patient sample.


High sensitivity and specificity for confidence in your results

greater than 96% clinical agreement
SimplexaTM Flu A/B & RSV Direct Clinical Agreement Summary
Positive % Agreement Negative % Agreement
SpecimenInfluenza A Sensitivity100.0% (55/55)
95% CI: 93.5 to 100.0%
Specificity97.8% (181/185)
95% CI: 94.6 to 99.2%
SpecimenInfluenza B Sensitivity100.0% (58/58)
95% CI: 93.8 to 100.0%
Specificity97.8% (178/182)
95% CI: 94.5 to 99.1%
SpecimenRSV Sensitivity100.0% (52/52)
95% CI: 93.1 to 100.0%
Specificity96.8% (182/188)
95% CI: 93.2 to 98.5%

Ordering info

Product Code Reactions

Simplexa® Flu A/B & RSV Direct Gen II*


* Direct Amplification Discs included in kit

Code MOL2655 Reactions 24

Simplexa® Flu A/B & RSV Direct Positive
Control Pack**


**Contains Inactivated influenza A virus, Inactivated influenza B virus, InactivatedContains inactivated influenza A virus, inactivated influenza B virus, and inactivated RSV.

Code MOL2660 Reactions 10

The Simplexa® COVID-19 Direct has not been FDA cleared or approved. It has been authorized by FDA under an EUA for use by authorized laboratories. The test has been authorized only for the detection of nucleic acid from SARS-CoV-2, not for any other viruses or pathogens. The Simplexa® COVID-19 Direct is only authorized for the duration of the declaration that circumstances exist justifying the authorization of emergency use of in vitro diagnostic tests for detection and/or diagnosis of COVID-19 under Section 564(b)(1) of the Act, 21U.S.C. § 360bbb-3(b)(1), unless the authorization is terminated or revoked sooner.

Code Reactions

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