Author: Alicia Maroney

The ability to identify foodborne pathogens quickly can determine whether an outbreak affects a handful of people or spreads across multiple states before its source is discovered. Advances in laboratory diagnostics are changing how public health officials identify infections, recognize emerging outbreaks, and trace contaminated food through the supply chain. One of the most significant developments is the growing use of culture independent diagnostic tests, commonly known as CIDTs. According to the Centers for Disease Control and Prevention’s preliminary 2024 Foodborne Diseases Active Surveillance Network data, 78% of reported bacterial infections covered by the analysis were diagnosed using CIDTs, compared…

Foodborne illness investigations are often most concerning when public health officials know people are getting sick but cannot yet determine what they ate. That is the situation facing federal investigators in October 2026. The U.S. Food and Drug Administration is actively investigating multiple outbreaks involving Salmonella, E. coli, and Listeria monocytogenes for which the implicated food has not yet been identified. As of October 4, seven such investigations were listed by the FDA, involving a combined 362 reported illnesses. The investigations involve three Salmonella outbreaks, one E. coli outbreak and three separate Listeria investigations. The largest is a Salmonella Newport…

Fall is often associated with changing leaves, cooler temperatures, football games and holiday gatherings. It is also the beginning of a period when foodborne illness risks can shift significantly. The foods served during fall celebrations create several opportunities for contamination. Large quantities of turkey, chicken, beef, stuffing, casseroles, gravies and other foods are prepared for family gatherings. Food may be transported from one location to another, placed on buffet tables and left at room temperature for extended periods. At the same time, the approach of colder weather creates conditions in which norovirus outbreaks become increasingly common. Foodborne illness does not…

Summer 2026 has produced an unusually concentrated series of foodborne illness outbreaks, recalls and public health warnings. The most consequential incidents have involved Cyclospora in iceberg lettuce, Salmonella in jalapeño peppers and shell eggs, E. coli in frozen blueberries, and a particularly unusual outbreak involving both E. coli and Salmonella in alfalfa sprouts. The outbreaks differ in their pathogens and food sources, but they share an important characteristic. Each demonstrates how a contaminated ingredient can move through a modern food supply chain faster than public health officials can identify it. The result is that consumers can become ill hundreds or…

One of the most misunderstood aspects of foodborne outbreak investigations is what it means when the CDC announces that an outbreak has expanded. Many consumers assume that adding additional states means contaminated food is continuing to spread throughout the country. In reality, expansion usually reflects something very different. It indicates that investigators have gathered sufficient scientific evidence to determine that illnesses reported in additional states are part of the same outbreak. The current cyclosporiasis investigation provides an excellent example of this process. During the early stages of the investigation, only a limited number of illnesses had been linked through epidemiological…

Foodborne illness investigations often focus public attention on a single restaurant, manufacturer, or food product. While identifying the immediate source of contamination is essential for protecting consumers, doing so can sometimes obscure a broader public health problem. The current increase in Cyclospora cayetanensisinfections illustrates this challenge. Although investigators have identified one confirmed outbreak associated with shredded iceberg lettuce supplied to Taco Bell restaurants, the Centers for Disease Control and Prevention (CDC) and the Food and Drug Administration (FDA) have made clear that this cluster does not explain all reported illnesses. Numerous additional cases remain under investigation, suggesting that multiple contamination events may…

Fresh produce occupies a unique position in modern nutrition and food safety. Public health agencies consistently encourage increased consumption of fruits and vegetables because they reduce the risk of cardiovascular disease, diabetes, obesity, certain cancers, and numerous chronic illnesses. At the same time, however, fresh produce has become one of the leading vehicles for foodborne disease outbreaks in the United States and around the world. Over the past two decades, the Centers for Disease Control and Prevention (CDC), the Food and Drug Administration (FDA), and state health departments have investigated numerous outbreaks linked to lettuce, spinach, cucumbers, onions, cantaloupes, tomatoes,…

Few food products carry greater public responsibility than infant formula. Unlike most processed foods, infant formula is designed to sustain life during a period when the immune system remains immature and nutritional requirements are extraordinarily precise. For many infants, including those born prematurely, those with metabolic disorders, or those unable to breastfeed, formula is not merely a dietary choice but a medical necessity. This dependence creates exceptionally high expectations regarding product safety. Parents assume that every container of infant formula has undergone rigorous testing and can be safely consumed without hesitation. When contamination occurs, however, the consequences extend far beyond…

One Contaminated Ingredient, Many Victims: How a Single Food Component Can Trigger Widespread Foodborne Illness Across Multiple Products Foodborne illness investigations often begin with what appears to be a simple question: What food made people sick? Increasingly, however, investigators discover that the answer is not a single finished product but a single contaminated ingredient shared across numerous products. In today’s food system, ingredients move through extraordinarily complex supply chains before reaching consumers. A spice harvested in one country may be blended into sauces, snacks, frozen meals, and restaurant foods. An onion grown on a single farm may eventually appear in…