Citing new research, the Food and Agriculture Organization of the United Nations (FAO) has highlighted the importance of Streptococcus agalactiae sequence type 283 (ST283), also known as Group B Streptococcus (GBS), as a zoonotic foodborne pathogen, as well as the usefulness of structured risk profiling and whole genome sequencing (WGS) analysis in addressing this atypical foodborne disease.

Transmission Pathways and Health Impacts

GBS ST283 presents a different symptomatic profile than other gastroenteric foodborne illnesses, as it is associated with invasive infections, including meningitis, septic arthritis, and bacteremia, and can affect individuals with no underlying health conditions.

Not only is exposure linked to the consumption of freshwater fish, but also to unsafe handling along the food chain, expanding the possible points of introduction to invasive foodborne disease. This is important to risk communication because bacterial hazards linked to aquaculture systems and handling practices can lead to severe outcomes, particularly when fish are consumed raw or undercooked or handled without adequate protection.

“The issue is not the consumption of fish per se, but the type of fish, how it is produced, and how it is prepared and handled,” said FAO.

The Importance of WGS

FAO emphasized the role that WGS has played in recognizing GBS ST283 as a foodborne hazard. Since the pathogen cannot be reliably distinguished using conventional microbiological testing methods, its identification relies on sequence-based approaches, the growing use of which has allowed ST-level differentiation and revealed links between human cases, fish, and environmental sources. FAO stressed that integrating WGS into food safety systems will be key to ensuring that GBS ST283 risks are recognized early and addressed effectively.

However, differences in national laboratory capacities and access to advanced tools like WGS influence detection, which means that the actual scale or distribution of GBS ST283 may be greater than currently understood.

Risk Profiling Implications

Hazards that do not fit neatly into established categories like GBS ST283 illustrate how risk is not defined by exposure alone, but by the combination of severity, transmission complexity, and system-level factors. It sits at the intersection of food production, environmental pathways, and human health, with links to aquaculture systems, multiple routes of transmission, and important gaps in data and surveillance.

FAO has identified GBS ST283 as a hazard requiring structured risk profiling, emphasizing the need to consider not only how often exposure occurs, but also what happens when it does.

Additionally, given the pathogen’s movement across humans, fish, and aquatic environments, a One Health approach is necessary for risk management.