As defined by the Centers for Disease Control and Prevention, a foodborne disease outbreak is a “cluster of two or more infections caused by the same agent (pathogen or toxin) which upon investigation are linked to the same food.” Foodborne outbreaks must be reported to the health department in Virginia as required by state regulation. Upon receiving notice of a suspected or confirmed foodborne disease outbreak, the Virginia Department of Health will start an investigation to confirm an outbreak has occurred. If it is determined that a foodborne outbreak has happened, the goals of the investigation are to identify the pathogen or “bad bug” (i.e. bacteria, virus, parasite) that caused illness in the outbreak, determine the source of illness and most importantly, control the spread of illness and prevent further spread of the disease. Virginia foodborne disease outbreak data may be reviewed on the Foodborne Disease Data Webpage.
If you believe that more than one person has become ill from gastrointestinal symptoms (such as diarrhea, nausea, vomiting, abdominal cramps) from a common food exposure, please report this occurrence to your local health district. In order to investigate a suspected foodborne disease outbreak, staff from the local health district will need to collect information from you by asking several questions. By providing the following information, you will help to start the investigation:
There are several steps involved during a foodborne disease outbreak investigation. Once a suspected outbreak is reported to the local health district, the health department attempts to collect initial information to better describe the who/what/when/where details of the occurrence. Often this involves the interviewing of the sick individuals involved with the suspected outbreak. At the same time, laboratory specimens may be collected by the health department from people that are sick. Testing of human specimens (usually stool) for suspected foodborne disease outbreaks is conducted at the state laboratory, the Division of Consolidated Laboratory Services. Details collected during interviews of the ill help outbreak investigators determine which pathogens to test for at the state laboratory. In addition, an inspection of the retail food establishment may occur in order to determine if any factors can be identified that may have led to this outbreak happening. If a restaurant or caterer was involved in the event, environmental health personnel from the Virginia Department of Health will be involved in the inspection. Other types of retail establishments would be inspected by the Virginia Department of Agriculture and Consumer Services. During these inspections of retail food establishments, environmental health specialists record all violations and discuss them with the person in charge, in an attempt to educate them to prevent any repeat occurrences. Certain critical violations are fixed immediately as they are found during the inspection.
As information is being collected, health department investigators are attempting to put the “pieces of the puzzle” together, to attempt to come up with an educated guess (otherwise referred to as a hypothesis) as to what might have caused this outbreak. If the health department finds a strong indication as to what might have led to the outbreak, an analytic study will be started. The purpose of the analytic study is to determine if a statistical link can be found between a particular exposure (food item) and the illness, showing an association between the two items. All persons involved in the outbreak event, including well persons, will be interviewed during the analytic study. After an investigation has been completed, a narrative report will be written by the local health district. The narrative report summarizes the findings of the outbreak investigation and provides recommendations to prevent its repeat occurrence in the future.