Acute flaccid myelitis – Summary and current Ontario situation

Advisory Alert

October 23, 2018

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To community health care providers:

There has been an increase in acute flaccid myelitis (AFM) with no known cause in children under 18 years of age in the United States. However, some cases have tested positive for non-polio enteroviruses, particularly enterovirus-A71 (EV-A71). This alert is to ensure that you are aware of the situation and remind you that that acute flaccid paralysis is reportable to Public Health Sudbury & Districts.

Increase in acute flaccid myelitis in the United States

The Centers for Disease Control and Prevention (CDC) has been working with state and local health departments and health care providers to investigate an increase in reports of suspected and confirmed cases of AFM in children under 18 years of age in the United States.

As of October 16, 2018, there have been 62 confirmed cases this year in 22 states. At this point, the cause of most cases of AFM is unknown; however, patients’ symptoms are similar to complications of infection from viruses such as enteroviruses (ex. EV-A71 and EV-D68), poliovirus, adenovirus and West Nile virus.

In 2014, an increase in AFM occurred at the same time as a national outbreak of EV-D68-associated respiratory infections and EV-D68 was found in respiratory specimens of some patients with AFM. From the initiation of their AFM surveillance in August 2014 through September 2018, 386 confirmed cases of AFM were reported, mostly in children.

Current Ontario situation

Acute flaccid paralysis (AFP): AFP is a reportable disease of public health significance in Ontario for children less than 15 years of age. AFP reporting is intended to ensure Ontario is monitoring for paralytic poliomyelitis infections in order for Canada to maintain its polio-free status. AFP is under-reported in Ontario with very few cases of AFP reported per year, likely due to lack of awareness of this reporting requirement. AFP monitoring for polio surveillance is also conducted by participating pediatricians through the Canadian Paediatric Surveillance Program. In the past few days, Public Health Ontario (PHO) has received an increasing number of reports of cases being investigated as AFP. Heightened awareness may have an impact on reporting frequency. As of October 18, 2018, there have been six recent reports in iPHIS of children under investigation for AFP from three health units, one of whom tested positive for EV-D68.

Enteroviruses: Non-polio enteroviruses are not a reportable disease of public health significance in Ontario. The laboratory at PHO tests for enteroviruses on request from respiratory specimens, cerebrospinal fluid, stool and other specimen types. Molecular serotyping, which can identify EV-D68 and EV-A71 along with other enterovirus subtypes, can also be performed at PHO. From September 1 to October 18, 2018, seven samples have tested positive for EV-D68 in respiratory specimens tested at PHO. Only one sample from August was positive for EV-A71.

Testing and Reporting

Health care providers ordering enterovirus/EV-D68 testing are required to complete a Clinical Summary Form (PDF) and a General Test Requisition Form (PDF) when submitting samples for EV-D68 testing.

These can be found on the PHO website at:

Should you require further information, or to report a case of acute flaccid paralysis please contact Public Health Sudbury & Districts at 705.522.9200, ext. 301.


Ariella Zbar, MD, CCFP, MPH, MBA, FRCPC
Associate Medical Officer of Health and Director of Clinical Services

This item was last modified on October 23, 2018