Lower riskMedical device recall · FDA · Published May 12, 2020
DiaSorin MOL3655 Simplexa VZV Swab Direct: False negatives due to software issue
DiaSorin recalls MOL3655 Simplexa VZV Swab Direct for potential false negative results from a software malfunction in the Multi Assay Suite. Affected lots were sold between September 2019 and February 2021.
Due to a software malfunction in the Multi Assay Suite, there is the probability of increased occurrence of false negative results.
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Contact the company
📍Recalling firmDiaSorin Molecular LLC11331 Valley View St · Cypress, CA 90630-5366
✎ GovInfoNow plain-language explainer
DiaSorin is recalling its MOL3655 Simplexa VZV Swab Direct product because a software issue in the Multi Assay Suite could cause false negative results. This means tests might incorrectly show no virus when it's actually present, which could lead to missed diagnoses. Read more at govinfonow.com/recall/65179-diasorin-mol3655-simplexa-vzv-swab-direct-false-negatives-due-to.
“DiaSorin MOL3655 Simplexa VZV Swab Direct: False negatives due to software issue.” GovInfoNow, updated August 19, 2026. https://govinfonow.com/recall/65179-diasorin-mol3655-simplexa-vzv-swab-direct-false-negatives-due-to. Based on FDA recall #Z-2549-2020 (https://api.fda.gov/device/enforcement.json?search=recall_number:%22Z-2549-2020%22&limit=1).
DiaSorin Molecular LLC recalled MOL3655 Simplexa VZV Swab Direct due to a software malfunction that may cause false negative results, the FDA said on May 12, 2020. The voluntary Class II recall affects products distributed worldwide.
A software malfunction in the Multi Assay Suite creates a probability of increased false negative results. The product is intended for qualitative detection of varicella-zoster virus (VZV) DNA in cutaneous and mucocutaneous lesion swabs.
Context
GovInfoNow's records show DiaSorin Molecular LLC has had four other recalls since September 23, 2021. Other recent recalls of similar products include Siemens Healthineers Immulite 2000 Syphilis Screen Recall (July 13, 2026), Vivoo Protein Test Recall (November 22, 2025), and Biomerieux VITEK 2 AST-N461 Test Kit Recall (July 24, 2026).
How to tell if you have this one
Check the lot number on the product label. Affected lots include 5743N (released Sept 2019, expires Sept 2020), 5819N (released Oct 2019, expires Oct 2020), and 5820N (released Feb 2020, expires Feb 2021).
Brand
DiaSorin
Category
Medical device
FDA recall event · 3 products
All 3 products in this recall
FDA lists each product line separately under one recall event. Check your product description, lot or code numbers against each row. Every row shares the hazard and remedy on this page.
Classification
Class II
Status
Terminated
Distribution
Worldwide distribution - U.S. Nationwide distribution including in the states of CO, FL, KS, MI, NC, PA, TX, and WA The countries of Austria, Czech Republic, France and Switerland.
Recall number
Product, codes & lots
Quantity
Z-2547-2020
MOL2150 Simplexa HSV 1&2 Direct -CSF -Genital Swab -Cutaneous / Mucocutaneous Swabs Product Usage: is intended for use on the LIAISON MDX instrument for the qualitative detection and differentiation of HSV-1 and HSV-2 present in cerebrospinal fluid (CSF), or cutaneous and mucocutaneous lesion swabs from patients with signs and symptoms of HSV-1 or HSV-2 infection of the central nervous system (CNS) or cutaneous and mucocutaneous lesions.; MOL2150 Simplexa HSV 1&2 Direct: Lot Numbers Release Date Exp Date 3606N 08/16/18 6/30/2020 3607N 08/31/18 6/30/2020 3609N 08/31/18 6/30/2020 3610N 10/08/18 7/31/2020 3615N 01/07/19 6/30/2020 3616N 11/28/18 6/30/2020 3618N 12/26/18 6/30/2020 3619N 12/26/18 6/30/2020 3847N 12/31/18 6/30/2020 3998N 07/20/18 5/31/2020 4000N 07/18/18 5/31/2020 4130N 03/05/19 6/30/2020 4131N 02/01/19 6/30/2020 4132N 02/15/19 6/30/2020 4134N 04/18/19 8/31/2020 4137N 04/04/19 8/30/2020 4138N 04/30/19 8/31/2020 4139N 07/12/19 5/31/2021 5171N 09/17/19 6/30/2021 5172N 09/03/19 6/30/2021 5173N 05/03/19 8/31/2020 5174N 06/04/19 8/31/2020 5175N 06/04/19 8/31/2020 5187N 07/19/19 5/31/2021 5188N 06/05/19 8/31/2020 5189N 07/25/19 5/31/2021 5190N 05/23/19 8/31/2020 5623N 07/25/19 5/31/2021 5738N 08/02/19 5/31/2021 5739N 08/20/19 6/30/2021 5793N 10/07/19 7/31/2021 5795N 03/09/20 12/31/2021 5841N 10/22/19 8/31/2021 5843N 10/31/19 8/31/2021 5845N 10/18/19 8/31/2021 5846N 04/06/20 1/31/2022 5846NA 04/16/20 1/31/2022 5847N 12/17/19 10/31/2021 5878N 03/11/20 1/31/2022 5888N 03/18/20 1/31/2022 R5170N 06/20/19 8/31/2020 R5201N 06/28/19 8/31/2020 R5202N 07/03/19 4/30/2021 R5283N 08/13/19 8/31/2020 R5285N 06/20/19 8/31/2020
13943 plastic vials (24 vials per box)
Z-2548-2020
MOL3650 Simplexa VZV Direct - Product Usage: is intended for use on the LIAISON MDX instrument for the qualitative detection of varicella-zoster virus (VZV) DNA in cerebrospinal fluid (CSF) from patients with signs and symptoms of VZV infections of the central nervous system (CNS).; MOL3650 Simplexa VZV Direct: Lot Numbers Release Date Exp Date 5178N 06/12/19 6/30/2020 7004N 03/04/20 2/28/2021
405 plastic vials (24 vials per box)
Z-2549-2020
MOL3655 Simplexa VZV Swab Direct - Product Usage: is intended for use on the LIAISON MDX instrument for the qualitative detection of varicella-zoster virus (VZV) DNA present in cutaneous and mucocutaneous lesion swabs from patients with signs and symptoms of VZV infection.; MOL3655 Simplexa VZV Swab Direct: Lot Numbers Release Date Exp Date 5743N 09/11/19 9/30/2020 5819N 10/09/19 10/31/2020 5820N 02/14/20 2/28/2021
304 plastic vials (24 vials per box)
Based on the official FDA remedy
What to do — step by step
Check Lot Number
Look for the lot number on the product label to determine if it's affected (5743N, 5819N, or 5820N).
Where it went and when
Where it was distributed
Distributed nationwide and abroad; the notice names 8 states.
Named in the notice
Covered by “nationwide”
Not listed
FDA distribution: “Worldwide distribution - U.S. Nationwide distribution including in the states of CO, FL, KS, MI, NC, PA, TX, and WA The countries of Austria, Czech Republic, France and Switerland.” States read from FDA’s own wording; “not listed” means the notice does not name it.
Named in the notice: Colorado, Florida, Kansas, Michigan, North Carolina, Pennsylvania, Texas, Washington.
Recall timeline
FDA terminated this recall 3.9 years after the firm started it.
1Firm started the recall
2FDA classified it Class II
3Published in FDA’s Enforcement Report
4FDA terminated the recall
Dates from the agency record only; steps without a date are left out.
The facts (hazard, remedy, dates, manufacturer) are pulled from the official FDA recall record. The plain-language summary and step-by-step checklist are written by GovInfoNow to make the official notice easier to act on — they don’t replace it.
Official source: FDA Recall #Z-2549-2020 (May 12, 2020) — FDA publishes no per-recall page; this is the official machine-readable enforcement record. Search FDA recalls for Z-2549-2020 to see it in context.
Plain-language summary written by qwen3:4b on August 19, 2026, from the official record above. Not reviewed by a person — if it conflicts with the FDA notice, the notice is correct. Report an error on this page.
GovInfoNow is an independent service and is not a government agency. We republish official FDA recall data; we don’t issue, amend or administer recalls.