Association between household exposure and cycle threshold in COVID-19 infected health care workers.

Details

• Personal Author:
  Blanc PD ; Chien A ; Domeracki S ; Guntur S ; Lampiris H ; Lu CM ; Taylor K
• Description:
  Objective: Household SARS-COV-2 contact constitutes a high-risk exposure for health care workers (HCWs). Cycle threshold (Ct) of reverse transcriptase-polymerase chain reaction testing provides an estimate of COVID-19 viral load, which can inform clinical and workplace management. We assessed whether Ct values differed between HCWs with COVID-19 with and without household exposure. Methods: We analyzed HCW COVID-19 cases whose Ct data could be compared. We defined low Ct at a cut-point approximating a viral load of 4.6 × 106 copies per ml. Logistic regression tested the association of household exposure and symptoms at diagnosis with a low Ct value. Results: Of 77 HCWs with COVID-19, 20 were household exposures cases and 34 were symptomatic at testing (7 were both household-exposed and symptomatic at testing). Among household exposures, 9 of 20 (45%) manifested lower Ct values compared to 14 of 57 (25%) for all others. In a bivariate model, household exposure was not statistically associated with lower Ct (Odds Ratio [OR] 1.20; 95% Confidence Interval [CI] 0.97-1.51). In multivariable modelling both household exposure (OR] 1.3; 95% CI 1.03-1.6) and symptoms at diagnosis (OR 1.4; 95% CI 1.15-1.7) were associated with a low Ct value. Discussion: Household exposure in HCWs with newly diagnosed COVID-19 was associated with lower Ct values, consistent with a higher viral load, supporting the hypothesis that contracting COVID-19 in that manner leads to a greater viral inoculum. [Description provided by NIOSH]
• Subjects:
  Communicable Diseases Environmental Exposure Health Personnel Occupational Health Safety Viral Diseases
• Keywords:
  Author Keywords: COVID-19; Health Care Workers; Household Exposure; Cycle Threshold SARS-CoV-2; Coronavirus; COVID-19; Health Care Workers; Environmental Exposure; Viral Infections; Infectious Diseases;
• ISSN:
  1745-6673
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Journal Article
• Place as Subject:
  California ; OSHA Region 9
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  29
• Volume:
  16
• Issue:
  1
• NIOSHTIC Number:
  nn:20065565
• Citation:
  J Occup Med Toxicol 2021 Aug; 16(1):29
• Contact Point Address:
  Paul D. Blanc, Occupational and Employee Health Section and Infectious Disease Section, Medical Service and Laboratory Medicine Service, San Francisco Veterans Affairs Health Care System, 4150 Clement St., San Francisco, CA, 94121, USA
• Email:
  paul.blanc@ucsf.edu
• Federal Fiscal Year:
  2021
• Performing Organization:
  University of California, Berkeley
• Peer Reviewed:
  True
• Start Date:
  20050701
• Source Full Name:
  Journal of Occupational Medicine and Toxicology
• End Date:
  20250630
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:ee610c2f2c9a84adf35c9c5adef6d1de50317d5617715f1d69ecfb9486f39b55b7a4ca7c34d303b0127bf27fc9304f509e1769e19ad6ce7bae66d897a607fcff
• Download URL:
  https://stacks.cdc.gov/view/cdc/248557/cdc_248557_DS1.pdf
• File Type:
  [PDF - 480.82 KB ]