EV-D68 cases spiked in 2018, new surveillance shows

Enterovirus D-68, or EV-D68, was detected in only two U.S. patients with acute respiratory illness in 2017. By 2018, nearly 14% of patients — mostly young children — tested positive for the virus, according to a recent MMWR.

EV-D68 has been a suspected cause of acute flaccid myelitis (AFM), a rare neurological condition hallmarked by limb weakness and paralysis.

Stephanie A. Kujawski, PhD, and colleagues wrote that the epidemiology of EV-D68 is not fully understood because not all health care facilities test for it, and when the disease is detected, it is not required to be reported to the CDC. However, the CDC began surveillance in 2015 for the virus among pediatric patients at seven medical centers that were part of the New Vaccine Surveillance Network.

According to the researchers, in 2017, 2,433 patients were treated for acute respiratory illness (ARI). Of these patients, two (0.08%) tested positive for EV-D68. Although a similar number of patients were treated in 2018 (n = 2,579), the researchers identified 358 (13.9%) patients who tested positive for the virus.

The median age of patients who tested positive was 3 years (range = 1 month-17 years; interquartile range = 1.5-5), and 58.9% were male.

The patients who tested positive in 2017 were located in Rochester, New York, and Houston, Texas. All seven states included in the network detected EV-D68 in 2018. Most patients with positive test results in 2018 (67.6%; range by site = 53.3%-76.8%) were hospitalized.

Kujawski and colleagues observed that nearly half of cases in 2018 occurred in September, but peak seasons varied across sites. For example, Cincinnati and Kansas City experienced a peak from late August through September, whereas Houston, Pittsburgh and Rochester experienced their peaks in mid-September, and Nashville and Seattle had peaks in October.

The researchers emphasized that continued active, prospective surveillance is necessary to better understand trends in EV-D68 circulation in the country.

“Although AFM is rare in the U.S., AFM surveillance data, along with the EV-D68 activity documented through the New Vaccine Surveillance Network, provide additional supporting evidence for a temporal association between EV-D68 respiratory illness and AFM, Kujawski and colleagues wrote. “CDC, in collaboration with clinical and public health partners, continues to investigate the relationship between AFM and enteroviruses, including EV-D68.” – by Katherine Bortz

Disclosures: Kujawski reports no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.

Enterovirus D-68, or EV-D68, was detected in only two U.S. patients with acute respiratory illness in 2017. By 2018, nearly 14% of patients — mostly young children — tested positive for the virus, according to a recent MMWR.

EV-D68 has been a suspected cause of acute flaccid myelitis (AFM), a rare neurological condition hallmarked by limb weakness and paralysis.

Stephanie A. Kujawski, PhD, and colleagues wrote that the epidemiology of EV-D68 is not fully understood because not all health care facilities test for it, and when the disease is detected, it is not required to be reported to the CDC. However, the CDC began surveillance in 2015 for the virus among pediatric patients at seven medical centers that were part of the New Vaccine Surveillance Network.

According to the researchers, in 2017, 2,433 patients were treated for acute respiratory illness (ARI). Of these patients, two (0.08%) tested positive for EV-D68. Although a similar number of patients were treated in 2018 (n = 2,579), the researchers identified 358 (13.9%) patients who tested positive for the virus.

The median age of patients who tested positive was 3 years (range = 1 month-17 years; interquartile range = 1.5-5), and 58.9% were male.

The patients who tested positive in 2017 were located in Rochester, New York, and Houston, Texas. All seven states included in the network detected EV-D68 in 2018. Most patients with positive test results in 2018 (67.6%; range by site = 53.3%-76.8%) were hospitalized.

Kujawski and colleagues observed that nearly half of cases in 2018 occurred in September, but peak seasons varied across sites. For example, Cincinnati and Kansas City experienced a peak from late August through September, whereas Houston, Pittsburgh and Rochester experienced their peaks in mid-September, and Nashville and Seattle had peaks in October.

The researchers emphasized that continued active, prospective surveillance is necessary to better understand trends in EV-D68 circulation in the country.

“Although AFM is rare in the U.S., AFM surveillance data, along with the EV-D68 activity documented through the New Vaccine Surveillance Network, provide additional supporting evidence for a temporal association between EV-D68 respiratory illness and AFM, Kujawski and colleagues wrote. “CDC, in collaboration with clinical and public health partners, continues to investigate the relationship between AFM and enteroviruses, including EV-D68.” – by Katherine Bortz

Disclosures: Kujawski reports no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.