A Foodborne Outbreak Associated with ST59-spa t441-SCCmec IVa Methicillin-resistant Staphylococcus aureus Producing Enterotoxins A and B - Puyang City, Henan Province, China, September 2024.

WHAT IS ALREADY KNOWN ABOUT THIS TOPIC?: Staphylococcus aureus (S. aureus) represents a clinically significant pathogen and serves as a common causative agent of foodborne intoxication. The S. aureus strain ST59 constitutes the predominant clone associated with both community-associated methicillin-resistant S. aureus (CA-MRSA) and hospital-associated MRSA (HA-MRSA) infections. However, staphylococcal food poisoning (SFP) outbreaks attributed to ST59 MRSA have been documented in only a limited number of Chinese cities through retrospective investigations.

WHAT IS ADDED BY THIS REPORT?: This report documents the first recorded outbreak of staphylococcal food poisoning (SFP) in Henan Province, which was attributed to the ST59-spa t441-SCCmec IVa CA-MRSA strain producing enterotoxins A and B. The confirmed source of the outbreak was contamination of donkey and goose meat with S. aureus enterotoxins A and B. Additionally, comprehensive genomic analysis identified multiple virulence genes and antibiotic resistance genes within the outbreak-related strains.

WHAT ARE THE IMPLICATIONS FOR PUBLIC HEALTH PRACTICE?: The identification of foodborne clones of ST59 CA-MRSA in this outbreak underscores the prevalence and transmission risks associated with this hypervirulent lineage. These findings highlight the critical need to strengthen surveillance measures for CA-MRSA among food industry workers and implement enhanced food safety protocols.