The Los Angeles County Public Health Laboratory (LAC-PHL) will only be accepting specimens for influenza virus
testing meeting the following criteria:
Reference Examination for Influenza A and B and/or Other Respiratory Viruses test request form must accompany each submission.
Refer to Test Request below.
Hospitalized Influenza Like Illness (ILI) patient
Fatal cases of Influenza Like Illness (ILI)
Contact to confirmed
case of novel or variant influenza
ILI with recent swine exposure
Outbreaks or cluster of cases with ILI
Designated surveillance sites
Specimens from the above criteria, other than designated surveillance sites, will be initially tested for
presence of Influenza A & B viruses by rt RT- PCR
If Influenza A virus is detected: sub-typing to identify Influenza A H1N1 (seasonal),
Influenza A 2009 A H1N1 (A/H1pdm09)
- formerly pandemic, Influenza A H3N2 (seasonal)
and presumptive variant Influenza A
H3N2v will be performed.
If no Influenza A or B virus is detected and specimen is from naso-pharyngeal source,
Luminex xTag RVP* will be performed.
Specimen sources other than naso-pharyngeal will only be tested for Influenza A
(seasonal and pdm09), Influenza A
subtypes; H1 (seasonal and 2009
H1) and H3 (seasonal and H3N2v) and Influenza B viruses.
For fatal cases and specific case request; If no virus detected by a PCR method, respiratory
viral culture will be performed.
Note: ONLY naso-pharyngeal specimens will be tested by Luminex xTag RVP.
* Respiratory Viral Targets included in xTag RVP: Respiratory Syncytial Virus’s (RSV) A&B, Influenza A (non-specific),
Influenza A subtypes H1 & H3, Influenza B, Parainfluenza’s 1, 2, & 3, Human metapneumovirus, rhinovirus and adenovirus.
Collection of Specimens and Storage:
Specimens should be collected within the
first 24-72 hours of symptom onset and no later than 4 days after symptom onset.
Personnel collecting clinical specimens should follow CDC safety guidelines.
Each specimen must be labeled with:
- Collect a naso-pharyngeal specimen using a Dacron-tipped or nylon flocked swab.
- Place the swabs in viral transport medium. Gel-based transport media are not acceptable.
- Please contact LAC-PHL for other specimen sources.
Specimen and Storage and Shipment:
Specimens should be kept refrigerated at 4ºC and
sent on cold packs if they can be received by
the laboratory within 72 hours of collection.
If specimens cannot be received by the laboratory within
72 hours of collection,
specimens should be frozen at -70 ºC or below and transported on dry ice.
Specimens should be submitted per usual protocol to:
Los Angeles County Public Health Laboratory,
Attn: Molecular Epidemiology,
12750 Erickson Ave. Downey, CA 90242-3456For courier assistance please call (562) 658-1341 or (562) 658-1460
Reference Examination for Influenza A and B and/or Other Respiratory Viruses test request form must
accompany each submission. This form provides the PHL Influenza testing method algorithm,
along with specimen collection and transport information and is available online at:
Please ensure that a completed form is submitted with all specimens. Testing may be
delayed if the form is not submitted with the specimen or is incomplete. Hospitals and Community Health
Centers with Sunquest direct or interface to the PHL Sunquest system must also include this form when
For Health Care Facilities with Sunquest direct test order access, please use test order
code “FLUPCR” for INFLUENZA COMPREHENSIVE test request.
Reflex Testing - LUMINEX xTAG RESPIRATORY VIRAL PANEL MULTIPLEX PCR and / or
Conventional Virus Culture, will be ordered and performed by LAC-PHL in accordance with above
For sites interfaced with LAC-PHL, results can
be accessed in the SunQuest software.
Results can be faxed to approved submitters with
an approved secure fax.