Severe respiratory illness sends kids to hospital in many states; No cases reported in N.C.

Severe Respiratory Illness Associated with Enterovirus D68

On Aug. 19, the CDC was notified by Children's Mercy Hospital in Kansas City, Missouri, of an increase (relative to the same period in previous years) in patients examined and hospitalized with severe respiratory illness, including some admitted to the pediatric intensive care unit. An increase also was noted in detections of rhinovirus/enterovirus by a multiplex polymerase chain reaction assay in nasopharyngeal specimens obtained during August 5–19. 

On August 23, CDC was notified by the University of Chicago Medicine Comer Children's Hospital in Illinois of an increase in patients similar to those seen in Kansas City. To further characterize these two geographically distinct observations, nasopharyngeal specimens from most of the patients with recent onset of severe symptoms from both facilities were sequenced by the CDC Picornavirus Laboratory. 

Enterovirus D68 (EV-D68) was identified in 19 of 22 specimens from Kansas City and in 11 of 14 specimens from Chicago. Since these initial reports, admissions for severe respiratory illness have continued at both facilities at rates higher than expected for this time of year. Investigations into suspected clusters in other jurisdictions are ongoing.

Of the 19 patients from Kansas City in whom EV-D68 was confirmed, 10 (53%) were male, and ages ranged from 6 weeks to 16 years (median = 4 years). Thirteen patients (68%) had a previous history of asthma or wheezing, and six patients (32%) had no underlying respiratory illness. 

All patients had difficulty breathing and hypoxemia, and four (21%) also had wheezing. Notably, only five patients (26%) were febrile. All patients were admitted to the pediatric intensive care unit, and four required bilevel positive airway pressure ventilation. Chest radiographs showed perihilar infiltrates, often with atelectasis. Neither chest radiographs nor blood cultures were consistent with bacterial coinfection. 

Of the 11 patients from Chicago in whom EV-D68 was confirmed, nine patients were female, and ages ranged from 20 months to 15 years (median = 5 years). Eight patients (73%) had a previous history of asthma or wheezing. Notably, only two patients (18%) were febrile. Ten patients were admitted to the pediatric intensive care unit for respiratory distress; two required mechanical ventilation (one of whom also received extracorporeal membrane oxygenation), and two required bilevel positive airway pressure ventilation.

Enteroviruses are associated with various clinical symptoms, including mild respiratory illness, febrile rash illness, and neurologic illness, such as aseptic meningitis and encephalitis. EV-D68, however, primarily causes respiratory illness (1), although the full spectrum of disease remains unclear. EV-D68 is identified using molecular techniques at a limited number of laboratories in the United States. 

Enterovirus infections, including EV-D68, are not reportable, but laboratory detections of enterovirus and parechovirus types are reported voluntarily to the National Enterovirus Surveillance System, which is managed by CDC. Participating laboratories are encouraged to report monthly summaries of virus type, specimen type, and collection date. 

Since the original isolation of EV-D68 in California in 1962 (2), EV-D68 has been reported rarely in the United States; the National Enterovirus Surveillance System received 79 EV-D68 reports during 2009–2013. Small clusters of EV-D68 associated with respiratory illness were reported in the United States during 2009–2010.

There are no available vaccines or specific treatments for EV-D68, and clinical care is supportive. Health care providers should consider EV-D68 as a possible cause of acute, unexplained severe respiratory illness; suspected clusters or outbreaks should be reported to local or state health departments. CDC's Picornavirus Laboratory (e-mail: wnix@cdc.gov) is available for assistance with diagnostic testing.

EV-D68 Infections Reported

• Hospitals in Missouri and Illinois are seeing more children than usual with severe respiratory illness caused by enterovirus D68.
• Several other states are investigating clusters of children with severe respiratory illness, possibly due to enterovirus D68.
• CDC is watching this situation closely and helping the states with testing of specimens.

Enterovirus D68

• Enterovirus D68 (EV-D68) is one of many non-polio enteroviruses. Enterovirus D68 (EV-D68) infections are thought to occur less commonly than infections with other enteroviruses. EV-D68 was first identified in California in 1962. Compared with other enteroviruses, EV-D68 has been rarely reported in the United States for the last 40 years.

Symptoms

• EV-D68 has been reported to cause mild to severe respiratory illness. However, the full spectrum of EV-D68 illness is not well-defined.

Transmission

• EV-D68 is not frequently identified, so it is less studied and the ways it spreads are not as well-understood as other enteroviruses. EV-D68 causes respiratory illness, and the virus can be found in respiratory secretions such as saliva, nasal mucus, or sputum. The virus likely spreads from person to person when an infected person coughs, sneezes, or touches contaminated surfaces.

Treatment

• There is no specific treatment for EV-D68 infections.
  • Many infections will be mild and self-limited, requiring only treatment of the symptoms.
  • Some people with severe respiratory illness caused by EV-D68 may need to be hospitalized and receive intensive supportive therapy.
• No antiviral medications are currently available for treating of EV-D68 infections.

Prevention

• There are no vaccines for preventing EV-D68 infections.
• You can help protect yourself from respiratory illnesses by following these steps:
  • Wash hands often with soap and water for 20 seconds, especially after changing diapers
  • Avoid touching eyes, nose and mouth with unwashed hands
  • Avoid kissing, hugging, and sharing cups or eating utensils with people who are sick
  • Disinfect frequently touched surfaces, such as toys and doorknobs, especially if someone is sick

By CDC