The incidences of a polio-like illness that mostly affects children appear to have peaked, the Centers for Disease Control and Prevention announced Monday.
The agency has confirmed 134 cases of the illness, called acute flaccid myelitis, or AFM, in 33 states. Another 165 cases have been reported to the CDC. Most cases appear to have occurred in September and October, and the CDC said it expected a decline that had been noticed in November to continue.
Officials liken the illness to polio because it affects the nervous system in a similar way, weakening patients’ muscles and making it difficult for them to move. People who are infected have trouble moving and develop a facial droop as well as slurred speech.
[Related: CDC creates task force to find cause of spike in polio-like illness afflicting kids]
The illness is still considered rare, but it raised alarm bells for public health officials because incidences rose this year and because its effects can be severe. It tends to mostly infect children, and has landed some of them hooked up to a respirator in intensive care. Some children recover while others can become paralyzed. Last year one child died after becoming ill.
Federal data suggest a pattern of higher infections every two years. In 2014, the CDC found 120 people had been infected, and the number dropped to 22 in 2015. The following year, it rose to 149 but then fell to 33 in 2017.
Scientists remain in the dark about the cause of AFM, but they think it may result from a viral infection. Neurological issues are often triggered by viruses, genetic conditions, or toxic chemicals in the environment.
So far the CDC has been able to knock out other causes that have been culprits in the past – including the respiratory illness enterovirus; the cold-causing rhinovirus; and West Nile Virus, which is carried by mosquitoes.
CDC officials have urged parents and their children to immediately seek medical care if they suddenly develop weakness in their arms or legs.
