Modelling Counterfactual Incidence During the Transition Towards Culture-Independent Diagnostic Testing

Authors

Jessica M. Healy, Division of Foodborne, Waterborne, and Environmental Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA.
Logan Ray, Division of Foodborne, Waterborne, and Environmental Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA.
Danielle M. Tack, Division of Foodborne, Waterborne, and Environmental Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA.
Dana Eikmeier, Minnesota Department of Health, St Paul, MN, USA.
Melissa Tobin-D'Angelo, Georgia Department of Public Health, Atlanta, GA, USA.
Elisha Wilson, Colorado Department of Public Health and Environment, Denver, CO, USA.
Sharon Hurd, Connecticut Emerging Infections Program, Yale School of Public Health, New Haven, CT, USA.
Sarah Lathrop, University of New Mexico Health Sciences Center, Albuquerque, NM, USA.
Suzanne M. McGuire, New York State Department of Health, Albany, NY, USA.
Beau B. Bruce, Division of Foodborne, Waterborne, and Environmental Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA.

Document Type

Article

Publication Date

10-11-2023

Abstract

BACKGROUND: Culture-independent diagnostic testing (CIDT) provides rapid results to clinicians and is quickly displacing traditional detection methods. Increased CIDT use and sensitivity likely result in higher case detection but might also obscure infection trends. Severe illness outcomes, such as hospitalization and death, are likely less affected by changes in testing practices and can be used as indicators of the expected case incidence trend had testing methods not changed.

METHODS: Using US Foodborne Diseases Active Surveillance Network data during 1996-2019 and mixed effects quasi-Poisson regression, we estimated the expected yearly incidence for nine enteric pathogens.

RESULTS: Removing the effect of CIDT use, CIDT panel testing and culture-confirmation of CIDT testing, the modelled incidence in all but three pathogens (Salmonella, Shigella, STEC O157) was significantly lower than the observed and the upward trend in Campylobacter was reversed from an observed 2.8% yearly increase to a modelled -2.8% yearly decrease (95% credible interval: -4.0, -1.4).

CONCLUSIONS: Severe outcomes may be useful indicators in evaluating trends in surveillance systems that have undergone a marked change.

Recommended Citation

Healy JM, Ray L, Tack DM, Eikmeier D, Tobin-D'Angelo M, Wilson E, Hurd S, Lathrop S, McGuire SM, Bruce BB. Modelling counterfactual incidence during the transition towards culture-independent diagnostic testing. Int J Epidemiol. 2023 Oct 11:dyad133. doi: 10.1093/ije/dyad133. Epub ahead of print. PMID: 37820050.