Increase in Acute Respiratory Illnesses Among Children and Adolescents Associated with Rhinoviruses and Enteroviruses, Including Enterovirus D68 - United States, July-September 2022

Abstract

Increases in severe respiratory illness and acute flaccid myelitis (AFM) among children and adolescents resulting from enterovirus D68 (EV-D68) infections occurred biennially in the United States during 2014, 2016, and 2018, primarily in late summer and fall. Although EV-D68 annual trends are not fully understood, EV-D68 levels were lower than expected in 2020, potentially because of implementation of COVID-19 mitigation measures (e.g., wearing face masks, enhanced hand hygiene, and physical distancing) (1). In August 2022, clinicians in several geographic areas notified CDC of an increase in hospitalizations of pediatric patients with severe respiratory illness and positive rhinovirus/enterovirus (RV/EV) test results.* Surveillance data were analyzed from multiple national data sources to characterize reported trends in acute respiratory illness (ARI), asthma/reactive airway disease (RAD) exacerbations, and the percentage of positive RV/EV and EV-D68 test results during 2022 compared with previous years. These data demonstrated an increase in emergency department (ED) visits by children and adolescents with ARI and asthma/RAD in late summer 2022. The percentage of positive RV/EV test results in national laboratory-based surveillance and the percentage of positive EV-D68 test results in pediatric sentinel surveillance also increased during this time. Previous increases in EV-D68 respiratory illness have led to substantial resource demands in some hospitals and have also coincided with increases in cases of AFM (2), a rare but serious neurologic disease affecting the spinal cord. Therefore, clinicians should consider AFM in patients with acute flaccid limb weakness, especially after respiratory illness or fever, and ensure prompt hospitalization and referral to specialty care for such cases. Clinicians should also test for poliovirus infection in patients suspected of having AFM because of the clinical similarity to acute flaccid paralysis caused by poliovirus. Ongoing surveillance for EV-D68 is critical to ensuring preparedness for possible future increases in ARI and AFM.

FIGURE 1

Weekly trends in the reported percentage of emergency department visits associated with acute respiratory illness (A) and asthma/reactive airway disease (B), in children aged 0–4 years, by age group and year — National Syndromic Surveillance Program, United States, January 2018–September 2022 Abbreviation: ED = emergency department. * The last reporting week (week 37) ended on September 17, 2022; data from this week are considered preliminary.

FIGURE 2

Weekly trends in the reported percentage of positive rhinovirus/enterovirus nucleic acid amplification test results, by year — National Respiratory and Enteric Virus Surveillance System, United States, January 2014–August 2022^,† Abbreviation: RV-EV rhinovirus/enterovirus. * The last complete reporting week (week 35) ended on September 3, 2022. ^† Enterovirus D68 detections were high during 2014, 2016, and 2018.

FIGURE 3

Weekly trends in reported percentage of positive enterovirus D68 test results among children and adolescents aged <18 years with acute respiratory illness and positive rhinovirus/enterovirus test results who received care in the emergency department or inpatient units — New Vaccine Surveillance Network, United States, 2017–2022 Abbreviation: EV-D68 = enterovirus D68. * The seven sites in the New Vaccine Surveillance Network are located in Kansas City, Missouri; Rochester, New York; Cincinnati, Ohio; Pittsburgh, Pennsylvania; Nashville, Tennessee; Houston, Texas; and Seattle, Washington. Two sites do parallel testing with a pan-rhinovirus and EV-D68 assay; fives sites do sequential testing with a pan-rhinovirus and pan-enterovirus assay or a rhinovirus/enterovirus assay, followed by an EV-D68 assay. All sites use the same CDC-developed EV-D68 reverse-transcription–polymerase chain reaction assay. ^† Testing for EV-D68 occurred at all seven sites during July–October 2017 and during July–November 2018–2020. Year-round testing began at most sites in July 2021 and was fully implemented at all sites during June 2022. EV-D68 testing windows in NVSN have changed over time, limiting annual comparisons outside of these windows. Retrospective testing is still in process for 2021 and early 2022, and data are current as of September 22, 2022. Weeks 33–35 are subject to delays in reporting.