Last year’s fruit salad Salmonella outbreak among health care facilities in several northeastern states was first identified by state and local officials. In this case, as is in many similar instances, it was local authorities who first brought the outbreak of Salmonella Oranienburg to the attention of federal authorities. A recently released Centers for Disease Control (CDC) report into the 2006 outbreak underscores the importance of monitoring programs at state and local levels in the fight against food borne illnesses.
Salmonella is a potentially deadly type of food poisoning, symptoms of which include fever, abdominal pain, nausea, gas and bloody diarrhea. Symptoms appear within 36 hours of exposure, and usually last four to seven days. Salmonella can be particularly dangerous for children, the elderly and people with weakened immune systems. Some victims of Salmonella will develop a disease called Reiter’s Syndrome, a difficult- to- treat condition that can lead to chronic arthritis. In the past several years, outbreaks of Salmonella poisoning have been traced to fresh tomatoes and other produce, as well as peanut butter, snack mix and pet foods.
In 2006, health officials in the Northeast began investigating an outbreak of Salmonella Oranienburg in healthcare facilities. Forty-one cases in the US and Canada would eventually be tied to fruit salad served at hospitals and nursing homes. The outbreak of the Oranienburg strain of Salmonella first came to the attention of health officials from the New Hampshire Department of Health and Human Services (NHDHHS), which officially began its investigation on July 19. The investigation was initiated after Salmonella Oranienburg was identified in stool samples taken from two patients, two employees, and a visitor who had eaten at the cafeteria of a local hospital. Just days later, on July 21, investigators in Massachusetts identified the very same strain of Salmonella bacteria in three residents of a long-term care facility. According to the CDC, health officials in both states submitted portions of their Salmonella samples to PulseNet, a national network for food borne disease surveillance. PulseNet determined that the Salmonella Oranienburg from both states had an identical genetic makeup, making it likely that the bacteria in the samples originated from the same source.
This finding led investigators from NHDHHS to contact officials in other states whenever they reported outbreaks of Salmonella Oranienburg between June and December 2006. Officials from New Hampshire reviewed records from all of these cases, conducted interviews and initially investigated nearly 300 potential sources of exposure. Of the 41 cases identified, 73% had occurred in patients who worked, stayed or ate in health care facilities. Interviews with 33 of those patients indicated that the Salmonella Oranienburg had come from fruit salad served at those institutions. The source of the outbreak was finally traced back to precut honeydew melon and cantaloupe purchased from the same processing plant in Canada. However, Canadian health officials were unable to find a source of contamination at that plant. The CDC report notes, however, that many fresh fruits and vegetables are contaminated with bacteria such as Salmonella while they are still in the fields.
The CDC report concludes that the 2006 fruit salad Salmonella outbreak highlights the importance of lab-based surveillance of Salmonella bacteria. Had health officials from New Hampshire and Massachusetts not submitted samples of Salmonella Oranienburg from their states’ outbreaks, the true nature and extent of the incident might never have become known.