Incidence and Trends of Infections with Pathogens Transmitted Commonly Through Food and the Effect of Increasing Use of Culture-Independent Diagnostic Tests on Surveillance - Foodborne Diseases Active Surveillance Network, 10 U.S. Sites, 2013-201

April 26, 2017 — 

Compared with the 2013-2015 average annual incidence, the 2016 incidence of confirmed Campylobacter infections was lower, incidences of confirmed Shiga toxin-producing Escherichia coli (STEC), Yersinia, and Cryptosporidium infections were higher, and incidences of confirmed or Culture-independent diagnostic test (CIDT) positive-only STEC and Yersinia infections were higher. However, CIDTs complicate the interpretation of surveillance data; testing for pathogens might occur more frequently because of changes in either health care provider behaviors or laboratory testing practices. A large proportion of CIDT positive specimens were not reflex cultured, which is necessary to obtain isolates for distinguishing pathogen subtypes, determining antimicrobial resistance, monitoring trends, and detecting outbreaks. [Source: CDC Morbidity and Mortality Weekly Report, April 21, 2017]

What are the implications for public health practice?
Some information about the bacteria causing infections, such as subtype and antimicrobial susceptibility, can only be obtained for CIDT positive specimens if reflex culture is performed. CIDTs are increasingly used by clinical laboratories to detect enteric infections. Increasing use of CIDTs affects the interpretation of public health surveillance data and ability to monitor progress toward prevention measures.

Read the entire report here.

Marder EP, Cieslak PR, Cronquist AB, et al. Incidence and Trends of Infections with Pathogens Transmitted Commonly Through Food and the Effect of Increasing Use of Culture-Independent Diagnostic Tests on Surveillance -- Foodborne Diseases Active Surveillance Network, 10 U.S. Sites, 2013-2016. MMWR Morb Mortal Wkly Rep 2017;66:397-403. DOI: http://dx.doi.org/10.15585/mmwr.mm6615a1