Poliovirus – Isolation and Characterization

Consistent with O. Reg. 671/92 of the French Language Services Act, laboratory testing information on this page is only available in English because it is scientific or technical in nature and is for use only by qualified health care providers and not by members of the public.

This page provides testing information for poliovirus accepted at Public Health Ontario (PHO). Specimens requesting for Poliovirus testing will be sent to the National Microbiology Laboratory (NML) for testing. For information regarding other testing options, refer to the following PHO webpages:

Testing Indications

Laboratory testing for poliovirus should be considered for patients presenting with:

  • Acute flaccid paralysis (AFP) in children <15 years of age
  • Acute flaccid myelitis (AFM) in any age
  • Poliomyelitis in any age

Testing should also be considered in cases with other acute neurological presentations of possible viral cause or clinical illness in a person who is epidemiologically linked to a laboratory-confirmed case.

For any suspected cases of poliovirus/poliomyelitis, contact Public Health Ontario Laboratory to discuss testing guidelines and provide notification.

Additional Testing Guideline for AFP/AFM at PHO’s Laboratory

Persons of any age presenting with AFM, or any child less than 15 years of age with AFP should have laboratory investigations to detect an infectious cause. Screening for viral pathogens may also be indicated for other neurological presentations where viral infection is on the differential diagnosis.

Testing should include Enterovirus detection, as well as Enterovirus molecular serotyping if Enterovirus-positive. See Enterovirus Test Information Sheet for specimen collection instructions for stool, respiratory, and cerebrospinal fluid (CSF) specimens and testing information.

Additionally, testing for Campylobacter should be performed if Guillain-Barre syndrome is suspected. Please refer to Enteric – Bacterial Culture Test Information Sheet for specimen collection instructions and testing information. Indicate on the test requisition “Campylobacter testing” in the Test(s) Requested field.

When submitting specimens from patients with neurological presentation, it is important to document the neurological symptoms on the laboratory requisition form, so the appropriate testing can be ordered.

Specimen Collection and Handling

Specimen Requirements

Test Requested Required Requisition(s) Specimen Type Minimum Volume Collection Kit


Stool (paired)3

2 x 2 grams

Virus – Enteric Kit order#: 390087

Submission and Collection Notes


Complete all fields of the requisition form, including:

  • Test(s) requests and indications for testing
  • Specimen type and date collected
  • Relevant clinical information (e.g. symptoms, date of symptoms onset)
  • Travel history
  • Relevant exposure, history or sick contact
  • Immunization history
  • Investigation or outbreak number

Label the specimen container with the patient’s full name, date of collection and one other unique identifier such as the patient’s date of birth or Health Card Number. For additional information see: Criteria for Acceptance of Patient Specimens. Failure to provide this information may result in rejection or testing delay.


Unpreserved stool in sterile leak proof container is the required specimen for poliovirus diagnostics as the likelihood of poliovirus isolation is the highest from stool. It is recommended to submit 2 stool samples taken at least 48 hours apart for patients with suspected poliomyelitis or acute flaccid paralysis. Ideally, these samples should be collected within 14 days after onset. Refer to the Virus-Enteric Kit Instruction Sheet for detailed specimen collection instructions.


Respiratory/oropharyngeal, serum and CSF specimen types are not recommended for poliovirus testing at the National Microbiology Laboratory (NML). If CSF, serum, or respiratory swabs are sent for poliovirus testing, they will not undergo poliovirus isolation, they will be referred for Enterovirus and Human Parechovirus molecular detection and typing.

Timing of Specimen Collection

To increase the probability of poliovirus isolation, obtain two stool specimens at least 48 hours apart from patients with suspected poliomyelitis. Ideally, these samples should be collected within 14 days after onset.


Rectal swab, respiratory/oropharyngeal, serum and CSF specimen types are not recommended for polio testing. Please refer to NML Poliovirus Isolation and Molecular Characterization.

Storage and Transport

Specimens should be frozen at -20°C following collection and shipped to PHO’s laboratory on dry ice.

All clinical specimens must be shipped in accordance to the Transportation of Dangerous Good Act.

Requisitions and Kit Ordering

Test Frequency and Turnaround Time (TAT)

Stool specimens are forwarded to NML for poliovirus testing Monday to Thursday.

Total turnaround time for the complete polio testing at NML may take up to 28 calendar days from receipt at NML.

Test Methods


When poliomyelitis is suspected in persons of all ages, or acute flaccid paralysis (AFP) occurs in children less than 15 years of age, PHO’s laboratory will conduct Enterovirus testing by Enterovirus PCR, and Enterovirus molecular serotyping on Enterovirus-positive specimens. For further information on Enterovirus testing, refer to the PHOL Enterovirus Test Information Sheet.

For additional information on the test methodologies and algorithms used to at NML, please refer to NML Poliovirus Isolation and Molecular Characterization. NML will determine the type of testing (PCR and/or virus culture) required for patient sample based on the patient’s clinical and exposure information.


Results are reported to the ordering physician, authorized health care provider (General O. Reg 45/22, s.18) or submitter as indicated on the requisition.

Specimens that are positive for poliovirus are reported to the Medical Officer of Health as per Health Protection and Promotion Act.

Additional Information

For information on Enterovirus PCR and Enterovirus Molecular Serotyping TAT, please see the PHO laboratory Enterovirus Test Information Sheet.

contact lab

Contact Laboratory Customer Service

Laboratory Services


Updated 11 Sep 2023