Another virus to keep track of… great
Enterovirus D68 (EVD68) is a non-enveloped, single-stranded RNA virus of the Enterovirus genus and the Picornaviridae family. It was first isolated from the respiratory tract in children in the 1960s, but it wasn’t until the 2000s that widespread infection was noted – specifically in the Philippines in 2008-09 where it caused severe respiratory symptoms. It is currently (we think) running roughshod across Pediatric Emergency Departments and Emergency Departments in North America, causing everything from garden variety cold symptoms, to respiratory distress replete with wheezing, retractions, and more.
I though Enterviruses cause GI symptoms – why all the wheezing?
EVD68 is genetically similar to rhinoviruses which may explain why it causes upper and lower respiratory tract symptoms. You may have seen PCR panels result positive for rhinovirus and enterovirus in the past. This strain is more likely to cause significant respiratory symptoms than some other rhino or entero strains.
It can cause a polio like illness called acute flaccid myelitis
EVD68 can target motor nuclei in the brainstem and spinal cord and lead to acute paresis of cranial and spinal nerves. This is called Acute Flaccid Myelitis. It can present first with fever, gait problems, and neck, back, and limb pain – later progressing to focal limb weakness and/or cranial nerve dysfunction. This was first noted concurrent with a surge of respiratory illnesses in 2014, then again in 2016 and 2018. We were ready for it to hit in 2020 but social distancing and masking during the early COVID-19 days likely curtailed that. 2022 is an “even” year, so we are again on the lookout. You should suspect AFM in children who develop acute weakness and know that you may only have your clinical history and a mild to moderate lymphocytic pleocytosis CSF and non-enhancing gray matter spinal cord lesions on MRI to help you make the diagnosis, since EVD68 is hard to isolate from the CSF. You may be able to isolate it from the nares, but…
Can we test for it?
…EVD68 testing, whether via antigen or PCR, is not readily available. This is a special “send out” often to government labs.
Any specific respiratory management pearls?
Most children with EVD68 infections are going to be OK. Those with respiratory distress will behave like bronchiolitis – and the pathophysiology of the virus is not going to cause bronchodilator responsive wheezing/respiratory symptoms in most. So, don’t give albuterol (which is in short supply) to all of these patients, but definitely do give it to those with a history of asthma who will likely benefit, and trial it in scenarios where the benefit is more likely (personal history of atopy, strong family history etc,.). Otherwise treatment is supportive. Acetaminophen, ibuprofen, suctioning, hydration – all the good stuff. You don’t need chest X-rays to make the diagnosis either – you’ll see features common to other viral lower respiratory tract infections – such as atelectasis, and peri-hilar infiltrates.
References
Imamura T et al. Global reemergence of enterovirus D68 as an important pathogen for acute respiratory infections. Rev Med Virol. 2015;25(2):102. Epub 2014 Dec 3.
Mertz D et al. Clinical severity of pediatric respiratory illness with enterovirus D68 compared with rhinovirus or other enterovirus genotypes. SOCMAJ. 2015;187(17):1279. Epub 2015 Oct 13.
Kujawski SA et al. Enterovirus D68-Associated Acute Respiratory Illness – New Vaccine Surveillance Network, United States, July-October, 2017 and 2018. MMWR Morb Mortal Wkly Rep. 2019;68(12):277. Epub 2019 Mar 29.
Modlin et al. Enterovirus and parechovirus infections: Clinical features, laboratory diagnosis, treatment, and prevention. Up To Date. Last Updated may 2022. Accessed September 21, 2022.
My experience with EVD-68 has been a bit different and have seen tons of patients with quite severe respiratory illness requiring ICU admission, positive pressure ventilation, etc. Have treated like asthma (bronchodilators, steroids, etc.) and seen good response with that approach. The tachypnea and retractions are out of proportion to the wheezing on auscultation. Quite a fascinating virus, surging now in Seattle.
Very interesting. Yes, many patients I have seen have sat with persistent symptoms for several days and been non-responsive to albuterol. The common thread is that it has made many many children quite ill. And it has done so over broad swath of our continent. That’s a very good point about the work of breathing being more significant than the auscultatory findings. Thanks!