Federal health officials are calling on doctors nationwide to be especially vigilant about recognizing and rapidly diagnosing a mysterious polio-like illness that primarily afflicts children and leaves some permanently paralyzed.
Acute flaccid myelitis, a viral infection simply known as AFM, strikes in late summer through early fall. Federal health officials say 2018 was a record year for the disease with an unprecedented upsurge. More than 200 children nationwide were diagnosed with the infection last year, including youngsters in New York State, where 39 cases were under investigation at the height of the outbreak last fall.
Since 2014, there have been 570 diagnoses across the country, according to the Centers for Disease Control and Prevention.
“We want clinicians and parents to be ready for a possible significant outbreak this year,” Dr. Anne Schuchat, principal deputy director of the CDC said during a telephone news briefing Tuesday, referring to the rare but serious disease. “One of the reasons we are reporting these results now in July is because it’s every August that we start to see an uptick.”
Doctors suspect the viral culprit at the core of the disease is an enterovirus — the same broad family of pathogens that includes the poliovirus. Experts, however, do not yet have enough evidence to say which virus is the cause of AFM.
In 2014, another AFM outbreak year, the most common virus isolated from spinal fluid specimens was an enterovirus dubbed EV-D68. But specimens collected in the latest nationwide cluster of cases did not implicate EV-D68 as the prime suspect.
Dr. Tom Clark, deputy director of the viral disease division at the CDC, said it is important for doctors to report suspected cases as soon as possible to aid the search for the disorder’s actual cause. A problem, he said, has been a nagging delay in getting specimens sent to the CDC.
“This delay in reporting kind of hamstrings our efforts,” Clark said Tuesday of conducting appropriate and rapid laboratory testing.
“We’re really trying to make the case that rapid recognition and reporting is what will help us collect the best specimens early enough to advance our understanding of what’s causing AFM,” he said.
The majority of children who developed limb weakness or paralysis had symptoms consistent with a viral infection with fever about a weak before serious limb problems occurred. All were previously healthy, according to data from a CDC report, which was released Tuesday to coincide with the news briefing. Siblings and close friends who developed the same flu-like symptoms at the same time emerged from the illness healthy, which has led some doctors to suggest a genetic flaw may underlie the disease. Limb weakness or paralysis can affect one or more extremities, doctors have found.
AFM, according to the CDC, can progress quickly from limb weakness to respiratory failure requiring urgent medical intervention, which is another reason that identifying symptoms early is important, according to the agency’s report.
Although Schuchat said federal officials are bracing for a possible surge in cases this year, the infection has had a surprising episodic nature over the past several years, experts have found.
Last fall, Dr. Stefan Hagmann, a specialist in pediatric infectious diseases at Cohen Children’s Medical Center in New Hyde Park, told Newsday that AFM tends to occur in specific cycles in even-numbered years. CDC doctors who addressed the news briefing also acknowledged a cyclic characteristic to the disease.
“The condition is on a biennial cycle, every two years,” Hagmann said last fall. “For us in our practice, it is not a very common condition. But in reading the [medical] literature and reports from the CDC, there is an increase in AFM cases every other year,” Hagmann said. “Many people have compared this condition to polio for obvious reasons. This reference for us is historical because my generation [of physicians] has not seen polio in the United States.”
Prior to the polio vaccine’s development in the 1950s, children were the usual targets of the poliovirus — an enterovirus — that generally caused illness in warmer months, especially summer.
The problems facing medical science now is pinpointing AFM’s cause and developing ways to aid patients who have permanent disabilities because of the disease.