C. difficile was responsible for almost half a million infections and was associated with approximately 29,000 deaths in 2011. (Funded by the Centers for Disease Control and Prevention.).

This report has been corrected. The definition of pediatric obesity was incorrectly stated in the text of the report and in the Table footnote; however, the analysis was correct and used the CDC definition of pediatric obesity for children aged ≥2 years (body mass index [kg/m2] ≥95th percentile for age and sex based on CDC growth charts).

Background Laboratory testing is helpful when evaluating patients with suspected Lyme disease (LD). A two-tiered antibody testing approach is recommended, but single-tier and non-validated tests are also used. We conducted a survey of large commercial laboratories in the United States to assess laboratory practices. We used these data to estimate the cost of testing and number of infections among patients from whom specimens were submitted. Methods Large commercial laboratories were asked to report the type and volume of testing conducted nationwide in 2008, as well as the percent of positive tests for four LD endemic states. The total direct cost of testing was calculated for each test type. These data and test-specific performance parameters available in published literature were used to estimate the number of infections among source patients. Results Seven participating laboratories performed ~3.4 million LD tests on ~2.4 million specimens nationwide at an estimated cost of $492 million. Two-tiered testing accounted for at least 62% of assays performed; alternative testing accounted for less than 3% of assays. The estimated frequency of infection among patients from whom specimens were submitted ranged from 10% to 18.5%. Applied to the total numbers of specimens, this yielded an estimated 240,000 to 444,000 infected source patients in 2008. Discussion LD testing is common and costly, with most testing in accordance with diagnostic recommendations. These results highlight the importance of considering clinical and exposure history when interpreting laboratory results for diagnostic and surveillance purposes.

this report was posted as an MMWR Early Release on the MMWR website (https://www.cdc.gov/mmwr).Although COVID-19-associated hospitalizations and deaths have occurred more frequently in adults, † COVID-19 can also lead to severe outcomes in children and adolescents (1,2). Schools are opening for in-person learning, and many prekindergarten children are returning to early care and education programs during a time when the number of COVID-19 cases caused by the highly transmissible B.1.617.2 (Delta) variant of SARS-CoV-2, the virus that causes COVID-19, is increasing. § Therefore, it is important to monitor indicators of severe COVID-19 among children and adolescents. This analysis uses Coronavirus Disease 2019-Associated Hospitalization Surveillance Network (COVID-NET) ¶ data to describe COVID-19-associated hospitalizations among U.S. children and adolescents aged 0-17 years. During March 1, 2020-August 14, 2021, the cumulative incidence of COVID-19-associated hospitalizations was 49.7 per 100,000 children and adolescents. The weekly COVID-19-associated hospitalization rate per 100,000 children and adolescents during the week ending August 14, 2021 (1.4) was nearly five times the rate during the week ending June 26, 2021 (0.3); among children aged 0-4 years, the weekly hospitalization rate during the week ending August 14, 2021, was nearly 10 times that during the week ending June 26, 2021.** During June 20-July 31, 2021, the hospitalization rate among unvaccinated adolescents (aged 12-17 years) was 10.1 times higher than that among fully vaccinated adolescents. Among all hospitalized children and adolescents with COVID-19, the proportions * These authors contributed equally to this report.

report receiving funding from the CDC EIP cooperative agreement. Libby Reeg and Laurie Billing report receiving a CDC federal grant from the Council of State and Territorial Epidemiologists. Laurie Billing reports receiving Epidemiology and Laboratory Capacity (ELC) grant funding from CDC to support vaccine preventable disease epidemiology staffing and additionally report receiving Immunizations and Vaccines for Children (VFC) grant funding from CDC. Evan Anderson has consulted for Pfizer, Sanofi Pasteur, Janssen, and Medscape, and his institution receives funds to conduct clinical research unrelated to this manuscript from MedImmune, Regeneron, PaxVax, Pfizer, GSK, Merck, Sanofi-Pasteur, Janssen, and Micron. He also serves on a safety monitoring board for Kentucky BioProcessing, Inc. and Sanofi Pasteur. His institution has also received funding from NIH to conduct clinical trials of Moderna and Janssen COVID-19 vaccines. The remaining authors have nothing to disclose.