CDC: Acute Flaccid Myelitis Cases Increased in 2018

Acute flaccid myelitis (AFM) is a rare polio-like condition that can cause limb weakness, and it mostly occurs in young children. This mysterious condition first emerged with outbreaks starting in 2014, which prompted the CDC to begin surveillance for the serious condition.¹

Pharmacists can play an important role as part of an interdisciplinary team to assist with referral and management of patients with AFM.

The CDC examined cases that occurred during 2018 through health department reports of patients meeting the clinical criterion for AFM, which was acute onset of flaccid limb weakness.² The report revealed that 233 AFM cases occurred in 41 states, which was the largest number since surveillance started in 2014, and the average age of patients was 5 years.^1,2 Additionally, the CDC received reports of suspected AFM cases on average 18 days after the patient’s limb weakness started. No deaths were reported during the acute illness in patients with confirmed AFM; however, 2 deaths occurred months after limb weakness began.

Evidence suggests that viruses such as enteroviruses play a role in AFM. The report showed that 44% of confirmed AFM cases in 2018 had an enterovirus or rhinovirus identified in respiratory specimens; however, about half were negative. Poliovirus does not cause AFM since the stool samples tested negative.

This report sheds light on the importance of early recognition of AFM so that patients are treated promptly. One limitation of the study is that there may be underreporting with surveillance monitoring, so the number of AFM cases may actually be higher.² Patients presenting with acute flaccid limb weakness, especially after respiratory illness or fever, between August and October (most cases occur in late summer and early fall) may be experiencing AFM.¹ These patients should be hospitalized, and specimens should be collected which include cerebrospinal fluid, serum, stool, and nasopharyngeal swabs. Patients should have an MRI, and if it shows a spinal lesion with some gray matter, then the health department should be contacted.²

Patients with AFM often need rehabilitation as part of the management process, which include physical and occupational therapy to improve outcomes. Specific treatments have not been extensively studied for AFM leaving no clear recommendations, but intravenous immunoglobulin, corticosteroids, and plasmapheresis may be considered as options to alleviate AFM symptoms.²

Future studies will include monitoring long-term outcomes of AFM and analyzing treatment options. Pharmacists should encourage parents to seek medical attention immediately if their children experience sudden arm or leg weakness. Since viruses may be associated with AFM, pharmacists should educate parents with the following tips to decrease the risk of their children becoming infected with a virus or spreading one:¹

• Wash hands frequently with soap and water
• Avoid touching the face or mouth with unwashed hands
• Avoid close contact with individuals who are sick
• Clean and disinfect frequently touched surfaces
• Cover coughs and sneezes
• Keep sick children at home

References

• Acute flaccid myelitis (AFM) Vital Signs. CDC website. https://www.cdc.gov/vitalsigns/afm/index.html. Accessed July 11, 2019.
• Lopez A, Lee A, Guo A, et al. Vital Signs: Surveillance for Acute Flaccid Myelitis-United States, 2018. MMWR Morb Mortal Wkly Rep 2019;68:608-614. DOI: http://dx.doi.org/10.15585/mmwr.mm6827e1.