U.S – Recent research conducted by the U.S. Centers for Disease Control and Prevention (CDC) has unveiled concerning findings regarding the outcomes of foodborne salmonellosis when the infecting pathogen exhibits antimicrobial resistance (AMR).
The study, which focused on nontyphoidal Salmonella infections in the U.S., discovered that cases involving AMR were significantly associated with worse clinical outcomes.
While infections caused by Salmonella with resistance only to clinically important antibiotics did not result in poorer outcomes, the study suggests that factors such as strain virulence, source, and host characteristics might play crucial roles.
Nontyphoidal Salmonella infections affect an estimated 1.35 million people in the U.S. annually, making it a significant public health concern.
Antimicrobial resistance is widely recognized as a major threat to global public health by both national and international health organizations.
In the study, CDC scientists examined the relationship between AMR in Salmonella isolates and clinical outcomes, including hospitalization, extended length of stay, and mortality.
Data from the CDC’s Foodborne Diseases Active Surveillance Network (FoodNet) was merged with antimicrobial resistance data from the National Antimicrobial Resistance Monitoring System (NARMS) for nontyphoidal Salmonella infections between 2004 and 2018.
The study revealed that infections involving Salmonella with any resistance were more likely to lead to hospitalization and longer hospital stays compared to non-resistant strains.
Notably, patients infected with strains showing clinical resistance to important antibiotics did not experience significantly worse outcomes.
After adjustments for various factors, any resistance and multidrug resistance (AMR for one or more antibiotics from three or more classes) remained significantly associated with hospitalization.
In 2019 alone, over 5,000 individuals worldwide lost their lives due to NTS infections resistant to antimicrobials, translating to a staggering burden of USD 50 billion.
This figure accounts for only one of over 30 pathogens responsible for antimicrobial-resistant foodborne diseases, illustrating the extensive and alarming scope of the problem.
These findings underline the critical need for continued research to assess the economic costs associated with resistant Salmonella, both direct and indirect.
Moreover, understanding the role of host and strain factors in determining clinical outcomes is essential for developing effective strategies to mitigate the impact of antimicrobial resistance.