The Centers for Disease Control and Prevention (CDC) has developed and started using a new, faster lab test for detecting enterovirus D68 (EV-D68) in specimens from people in the United States with respiratory illness.
CDC’s new lab test is a “real-time” reverse transcription polymerase chain reaction, or rRT-PCR, and it identifies all strains of EV-D68 seen this summer and fall. The new test has fewer and shorter steps than the test that CDC and some states were using for the EV-D68 outbreak. Also, the new test allows more specimens to be tested at the same time.
The previous test, which CDC used for about nine years, is very sensitive and can be used to detect and identify almost all enteroviruses; however, it requires multiple, labor-intensive processing steps and cannot be easily scaled up to support testing of large numbers of specimens in real time that is needed for the current EV-D68 outbreak.
Every year, enteroviruses and rhinoviruses cause millions of respiratory illnesses in children. This year, EV-D68 has been the most common type of enterovirus identified, leading to increases in illnesses among children and affecting those with asthma most severely. Other rhinoviruses and enteroviruses continue to be detected as well.
CDC expects, as with other enteroviruses, that EV-D68 infections will likely begin to decline by late fall. The real-time lab results combined with data on hospital admissions will help us understand when and where the EV-D68 outbreak is ending.
“CDC has received substantially more specimens for enterovirus lab testing than usual this year, due to the large outbreak of EV-D68 and related hospitalizations,” said Anne Schuchat, MD, assistant surgeon general and director of CDC’s National Center for Immunization and Respiratory Diseases. “When rare or uncommon viruses suddenly begin causing severe illness, CDC works quickly to develop diagnostic tests to enhance our response and investigations. This new lab test will reduce what would normally take several weeks to get results to a few days.”
Since the outbreak of EV-D68 began in August, CDC has tested 1163 specimens submitted by hospitals and from 45 states. Of the specimens tested by the CDC lab from August 1 to October 10, about half have tested positive for EV-D68. About one third have tested positive for a rhinovirus or an enterovirus other than EV-D68. The new lab test will allow us to process the approximately one-thousand remaining specimens at a much faster rate.
Source: CDC press release, adapted.