Test Order - Influenza A(H5) Real-time PCR
Synonym(s) - Influenza A(H5) PCR
Methodology - Real-time polymerase chain reaction (PCR)
Acceptable Specimen Type(s) for Testing -
For individuals that meet clinical and epidemiologic criteria for influenza A(H5) collect the following specimens depending on symptomology:
- Upper respiratory specimens: anterior nares swab and oropharyngeal swabs, in separate transport media vials.
- Lower respiratory specimens: Patients with severe respiratory disease should also have lower respiratory tract specimens collected such as an endotracheal aspirate, bronchoalveolar lavage, or sputum.
- For patients with conjunctival symptoms: For individuals that meet the clinical and epidemiological criteria for influenza A(H5) with conjunctivitis (with or without respiratory symptoms) If conjunctivitis is present in both eyes, collect separate swabs from each eye and combine the swabs in a single transport media vial. Instructions for conjunctival Sample collection can be found under the Additional Collection instruction section. Conjunctival specimens from patients with conjunctivitis have been more sensitive for detection of Influenza A(H5) than other specimens to date in 2024.
- Patients who have ingested raw dairy products and have gastrointestinal symptoms, with or without respiratory symptoms, may also have a stool specimen collected in Cary Blair to be tested for enteric pathogens with the Biofire GI panel. Visit the Gastrointestinal Panel for specific collection instructions.
SERUM: ONLY COLLECT SERUM IF DIRECTED BY SAN FRANCISO COMMUNICABLE DISEASE
Serum: Collect Tiger tops or SST (gold top) tubes per manufacturer instructions. If tiger top vacutainers are not available, please use 2 gold top vacutainers. Do not shake the tubes. Vigorous mixing may cause foaming or hemolysis. Insufficient mixing or delayed mixing in serum tubes may result in delayed clotting. Collected blood should be stored at 4°C immediately and centrifuged within 24hrs of collection. If centrifugation is not available submit the specimens to the laboratory within 24 hrs. of collection. If centrifugation is available: BD vacutainer SST tubes can be centrifuged at 1100 to 1300g for 10 minutes in swing-head units or 15 minutes in fixed angle centrifugation units (balance the tubes in the centrifuge). Submit specimens to the laboratory as soon as possible.
Transport / Collection Medium - Swab specimens should be collected and placed into Universal viral transport media (VTM or UTM) Specimens should be refrigerated at 2 to 8⁰C for up to 72 hours. Alternatively ship specimens on dry ice in compliance with DoT and IATA regulations governing Biological Substances, Category B (UN 3373) Monday through Thursday. Specimen can also be sent via courier Monday-Friday 8:00am-5:00pm. Serum specimens should be collected in tiger tops or 2 SST (gold top) vacutainers for children (3 to 11 years) or teens and adults (≥12 year of age) and 1 SST (Gold top) tubes for pediatric patients (≤3 years of age).
Storage and Preservation of Specimen - Swab specimens collected in VTM should be stored at 2 to 8⁰C for up to 72 hours and submit to the laboratory as soon as possible; otherwise freeze at ≤-70⁰C. Store serum specimens at 4°C immediately after collection and submit to the laboratory within 24 hours of collection.
Minimum Volume Required -
Swabs: 3 milliliters for swabs collected in VTM
Serum:
Pediatric patients: 5.0 milliliters of whole blood
Children: 5-10 milliliters of whole blood
Teens and adults” ≥10 milliliters of whole blood
Additional Collection Instructions -
Contact San Francisco Communicable Disease Control at 6628-217-6100 prior to requesting this test. SFPHL requisition required for all specimens. In addition, please fill out CDC 50.34 Specimen submission form. Reference Conjunctival Sample Collection Instructions for Influenza A(H5) Testing for additional information
Additional Required Information - Label specimens with at least 2 patient identifiers.
Send Out? - Serum testing will be performed by the Centers for Disease Control and Prevention.
Turnaround Time - 24 hours
Testing Restrictions - Results for this test will be reported as “presumptive”. Specimens will be sent to CDC for confirmation.
Limitations / Notes / Disclaimers -
Please refer Centers for Disease Control Health Alert Network for Influenza A(H5). Please refer to CDPH’s Human Influenza A(H5N1) guidance (December 13,2024) Please refer to CDPH’s Evaluation and Testing for Human Avian Influenza A (H5N1) Infection guidelines