Enterovirus D68: What we know now
The Doc Smitty looks at EVD68 after new reports of paralysis and death
Enterovirus D68 has officially spread across the country, identified in 40 states and locally in Dallas and Denton counties. There have yet to be positively identified cases in Tarrant County, although there are individuals here that have not been ill enough to warrant specific testing. The latest news concerning Enterovirus D68 involves cases of paralysis and four deaths that the CDC have reported to be associated with the virus. I want to stress that the role of enterovirus with these findings is still under investigation and that, even if it is associated, they are extremely rare.
It may surprise you to know that there are more than 100 known varieties of non-polio enteroviruses in the world. All of these different types of enteroviruses can cause confusion and panic.
The non-polio enterovirus strains range from the common cold to meningitis. You may have noticed those strains are non-polio enteroviruses, which means that yes, an example of an enterovirus strain that can cause paralysis is polio.
Approximately 1 in 200 infections with polio will cause paralysis. Other enterovirus strains can cause similar symptoms, but do so much less frequently.
There have been a few reports stating that cases of EVD68 have possibly been associated with paralysis, most notably 10 cases in Colorado, 5 cases in California and now a case identified in Dallas. The most common locations for weakness have been the upper arms and hips.
But much work still needs to be done to decide what role EVD68 played in the paralysis. In a published Morbidity and Mortality Weekly Report last week, only four of the 10 children in Colorado tested positive for EVD68.
Investigation is ongoing to determine if these cases were actually caused by the virus. Those patients affected will be undergoing extensive physical therapy to regain function.
The CDC released a report this week that announced there have been five deaths in which enterovirus D68 has been associated. We currently don't know the details of two of these cases. We do not know where the patients lived, their ages or if they had other medical conditions. These would all be important factors in determining the cause of death. The fourth patient was a 10-year old girl from Rhode Island who tested positive for enterovirus D68, but also for a bacteria in her blood stream called Staphylococcus aureus. Staph aureus infections are known to be dangerous, often progressing rapidly, and are resistant to many antibiotics.
Another case reported today described a boy who after an unexplained death was found to be positive for enterovirus D68. Prior to his death, he showed no signs or symptoms of upper respiratory infection, other than a case of pink eye which was proven not to be connected to EVD68. Because of these complicating factors, it is unclear what role EVD68 played in these deaths.
It is entirely possible that the others had similar stories with multiple infections or that they had other chronic health conditions which put them at risk for complications. At this point, I continue to believe that, in almost all children, enterovirus D68 causes mild runny nose and cough and that our biggest complication is the progression towards wheezing. Again, there are not many details out surrounding the deaths, but we felt it was important to update you on the situation given that we have stated all along that there had been no deaths clinically caused only by enterovirus D68. We will follow along and update you as soon as we know more.
Enterovirus D68 peaks in late summer and early fall so I expect that the number of cases to begin dropping soon (if it is not already on the way down). Other regions that experienced earlier outbreaks have already seen the end…they are doing what we will be doing soon, preparing for flu.
Justin Smith, M.D., is a Cook Children's pediatrician in Lewisville . He attended University of Texas, Southwestern Medical School and did his pediatric training at Baylor College of Medicine. He joined Cook Children's after practicing in his hometown of Abilene for four years. He has a particular interest in development, behavior and care for children struggling with obesity. In his spare time, he enjoys playing with his 3 young children, exercising, reading and writing about parenting and pediatric health issues.