Florida’s coastline and climate present both an attractive destination for a dynamic tourist population and for the ever-growing retirement community. The demographics of these groups contribute to unique issues concerning emerging food-borne diseases. Vacationers are far more likely to be exposed to contaminated food in restaurants than at home, simply due to the volume of food processed. New and exotic foods may mean exposure to new and exotic infections. Tracking sources of infection among tourists presents difficulties when the affected persons do not become ill until after they return home. Aging populations in our state are generally declining in their ability to combat infectious disease; consequently, they become much more susceptible to most food-borne illness. The elderly and persons with other immune deficiencies, such as HIV, can harbor emerging diseases that are not evident in healthy populations. The port cities of Florida often provide the first point of US contact for infected persons or contaminated food sources. Ballast water from ships may carry pathogens around the world, contributing to the spread of pandemic disease. Many of these diseases are not typically found in the US and are a source of emerging infections.
Today both the USDA and FDA maintain vigorous standards to ensure food and water safety, but the challenge is daunting. Systems such as inspection and testing, HACCP (hazard analysis critical control points, and GAPS (good agricultural practices) and others have been put in place to minimize contamination in food sources from the point of harvest to the presentation of food on the table. HACCP was developed as a byproduct of another Florida industry, namely the space program, to ensure that astronauts would not become stricken during space travel. NASA recognized that it was virtually impossible to test every item of food for every potential pathogen; therefore, a strict code of standards at appropriate checkpoints was established to ensure food safety. This process is now in place throughout the entire food industry, and recent indications suggest that it may be responsible for substantial declines in food-borne diseases.
Today’s food industry is not only concerned with maintaining the highest quality and safest product during normal conditions but is also evaluating procedures that may need to implemented in times of natural or manmade disasters, such as hurricanes, terrorist acts, or large epidemics. As seen recently with Katrina, disruption in the distribution of both food and water can create even greater burdens in affected areas and prolong the time needed for recovery.
SALMONELLA: AN OLD ENEMY IN NEW PLACES
Salmonella enterica (subtype Typhi) is the causative agent of typhoid fever, which plagued the US in the nineteenth and early twentieth centuries. This frequently fatal disease was contracted through contaminated food and water, but occasional asymptomatic carriers like the infamous "Typhoid Mary" also spread disease. Today improved hygiene and surveillance have virtually eliminated the threat to this country. However, milder Salmonella illnesses are one of the largest contributors to food-borne disease in the US, and because of the large numbers of persons affected, mortality is still significant. Notably, the first reported incident of terrorism in the US involving food occurred when a group purposefully contaminated salad bars with Salmonella, resulting in more than 700 illnesses.
Closely related strains of the same species that caused typhoid fever now produce diarrheal disease with much less severe symptoms and outcome. These strains became endemic in commercial chicken populations, and most outbreaks of Salmonella gastroenteritis were associated with undercooked poultry or eggs. However, several recent large outbreaks in Florida have been traced back to rather unusual sources involving unpasteurized orange juice or salad tomatoes. Interestingly, contamination of oranges attributed to contact of the product with tree frogs that are ubiquitous in Florida and can harbor the bacterium. These types of produce are typically too acidic for growth of most bacteria and are usually not implicated food-borne infections. Their association with Salmonella disease is of particular concern because the products are often consumed without cooking. These new cases may indicate evolution of the species towards adaptations that increase their survival in acidic foods. Alternatively, introduction of new strains in the food supply may be associated with climatic changes, migrating birds, or unsafe harvesting and production practices. Avoiding unpasteurized juices and more extensive washing of produce will greatly reduce the risks to the consumer.