Clarification from CDC on Case Confirmation

So that we can make sure that the magnitude and severity of AFM is truly understood, we must ensure that all cases of AFM are reported to Center for Disease Control (CDC).

Currently, here’s how a suspected AFM case is reported to the CDC: Physicians are encouraged (but unfortunately, not required) to report cases to their local health departments. These health departments report to the CDC, and the CDC classifies the case as either fitting criteria for AFM, or not fitting criteria for AFM. After the CDC classifies the case, local health departments relay the case status to the physician, who in turn, alerts the family. This is a lengthy process with many levels. We encourage parents to reach out to their local health departments to find out the status of their child’s case, if they haven’t received an update in a timely manner.

In some cases, parents have felt understandably frustrated when a doctor diagnoses their child with AFM, but the CDC classifies the child as “not AFM.” We reached out to the CDC to better understand how they decide to define a specific case as AFM or not. The CDC’s response is as follows:

CDC has case definitions for AFM with specific criteria that we use to classify patients as having a confirmed or probable case of this illness. If a patient does not meet these criteria, they are classified as “not a case” of AFM.  Our AFM case definitions provide a set of consistent criteria to help us define and learn more about this rare condition, and they are the basis for our AFM surveillance. A case classification by CDC is not meant to override a doctor’s diagnosis of a patient’s illness, or his or her treatment and rehabilitation plan. Even though some patients may not meet our case definitions, they are still counted in our AFM surveillance and help us understand the full spectrum of illness. We continue to evaluate our case definitions as we learn more about AFM.

Generally for disease surveillance, the primary goal is to better understand how often a disease occurs and how it affects a population. For our AFM surveillance, we have the additional challenge of trying to figure out what is causing this condition. In order to do this, we need to make sure our case definitions are ruling out other similar conditions, such as transverse myelitis and Guillain–Barré syndrome. This helps us make sure that we are comparing the patients with the most similar illness for risk factors and possible causes, which gives us the best chance of understanding this condition.

I personally was frustrated when I found out that my son’s case from 2016 was not counted as AFM by the CDC. When we reached out, we realized that they didn’t have the MRI showing the inflammation to the grey matter-- a previous MRI was sent that had been read as normal. The CDC isare currently in the process of updating my son’s case.

We encourage parents to reach out in an attempt to determine their child’s case status. Our goal is for the CDC (and other researchers) to have as much information as possible about all cases of AFM in order to improve diagnosis, treatment and prevention in the future.

AFM parents after presenting to the AFM Task Force about their experience with AFM.

AFM parents after presenting to the AFM Task Force about their experience with AFM.