Tracking cases of child paralysis may be paying off, former CDC expert reports
Doctors are now testing common enteroviruses
Recent cases of polio-like paralysis in children are alarming, but the numbers nationwide are lower than in spikes in 2014 and 2016 and that may indicate some progress, according to pediatric infectious disease expert Rishi Desai. Dr. Desai, of Oakland, Calif., previously worked for the Centers for Disease Control and Prevention investigating viral disease outbreaks.
Tracked since an upswing in 2014, cases of acute flaccid myelitis are still rare. Three children with confirmed AFM and three suspected cases have been reported treated at UPMC Children’s Hospital of Pittsburgh.
Spikes of the syndrome have been noted in two-year cycles, with 120 cases in 2014, 22 in 2015, 149 in 2016, 33 in 2017 and 62 so far in 2018.
“In general,” Dr. Desai said Tuesday, “if we saw 120 to 150 cases [in earlier spikes], and now we have 62 cases, we’re already doing a better job than two years ago, if we think the numbers are right.”
An early diagnosis is recommended for the best outcomes in patients, starting with MRIs that can detect the specific sign of AFM: a lesion in the gray matter of the spinal cord. Blood samples, mouth swabs and stool specimens are taken and tested for DNA from suspect viruses. Doctors are now regularly testing AFM patients for signs of common enteroviruses linked to many cases — including enterovirus D-68, known to cause coughing, sneezing and fever.
There are some treatments used to relieve the muscle weakness of AFM, Dr. Desai said, including
intravenous immunoglobulin therapy and high-dose intravenous steroids, documented as used successfully in a case study of a Taiwanese child with AFM, in a recent medical journal.
Patients are treated primarily with supportive care (help if needed with eating, drinking, breathing) and physical therapy. The twoyear cycle is a clue that the syndrome is caused by an infection, Dr. Desai said, citing the flu’s cycle as an example:
“With influenza, we know that every 20 years we have a big outbreak,” he said. “It’s logical: We all see this brandnew virus. It wrecks havoc on our immune system,” he said. People develop an immune response to the virus that protects them from serious illness.
“It’s sufficient,” he said. “Then we have a change every 20 years and everyone’s a naive population again. … We act as if we’ve never seen it before.” Rotovirus is another that has periodic surges in the number of cases, he added.
He said the enterovirus may be having the same effect — although no single virus has been linked to all 62 cases this year, according to the CDC.
Dr. Desai said the CDC reports numbers of AFM cases going up and down over the past four years, but he cautioned against following them too closely.
“These numbers suggest some waxing and waning, but sometimes you miss cases; they’re not reported,” he said. A parent might not recognize weakness in a child’s hand, attributing it to a play or sports injury.
“Some cases fly under the radar. … [We shouldn’t take] too much stock in the exact numbers.”
At the same time, he said, “The CDC is doing a good job.” More diagnoses over time may help, along with information gathered about other viruses.
“We have these fantastic surveillance systems in place,” Dr. Desai said. Tracking flu cases and numbers of patients hospitalized is a much larger task than the AFM cases, which are far fewer, with most children recovering.
There’s also a fast, inexpensive technique to copy DNA segments to identify viruses in the patients’ specimens, he said. “They’re looking at adenovirus, enterovirus, West Nile virus. These are the viruses to look for.”
Parents are bringing their children to the doctor sooner, he said, and that is good news. There may be others, however, who are not being tested for AFM and the viruses — possibly people living in temporary housing due to hurricanes, he said.
“The majority get better or somewhat better. … Most of the time they walk out of the hospital,” Dr. Desai said. “[But] it’s a terrible twoweek experience for parents.”
Dr. Desai is chief medical officer at Osmosis, an online clinical education resource for medical students and the public. For an Osmosis video on acute flaccid myelitis, go to: https://youtu.be/SC3Z2XZKqs.