Campylobacter is part of the natural gut microflora of many of the animals that humans eat – chickens, turkeys, swine, cattle and sheep. A contaminated poultry carcass can carry anywhere between 100 and 100,000 Campylobacter cells. Given that it only takes 500 Campylobacter cells to cause infection, consumers can face significant risk.
There are 17 known species of Campylobacter, and at least a dozen species have been implicated in human illness. The most infamous is Campylobacter jejuni, a nonsporeforming, Gram-negative rod, recognized as one of the main culprits overall for bacterial foodborne illnesses. Scientists estimate that more than 80 percent of Campylobacter infections are caused by C. jejuni.
C. jejuni and the other members of the Campylobacter genus grow at lower than atmospheric oxygen concentrations, typically 3 to 5 percent. Consequently, they are somewhat fragile in the ambient environment and difficult to culture in the laboratory.
The main food sources linked to C. jejuni infections include improperly handled or undercooked poultry products, raw milk, cheeses made from unpasteurized milk and contaminated water. It’s worth noting, though, that C. jejuni has occasionally found in a variety of other places, from vegetables to seafood to pond water.
Campylobacter species are among the leading causes of domestically acquired bacterial foodborne illness in the United States, with nearly 1.3 million cases occurring annually, according to data from the U.S. Centers for Disease Control and Prevention (CDC). For each reported case of campylobacteriosis, 30 cases are projected to be unreported.
Overall the CDC attributes an estimated 76 deaths in the United States per year to campylobacteriosis. And in addition to causing fatalities, C. jejuni has also been linked to autoimmune disorders with scientists believing that antigens present in the pathogen resemble those in certain nervous tissues in humans and lead to reactions. Children less than 5 years old (especially less than 1 year) and young adults between 15 and 29 years in age are C. jejuni’s most common human hosts. The bacterium also has a disproportionally large effect on pregnant women, not only sickening them but causing infection in their fetuses, which can sometimes lead to miscarriage or stillbirth.
Campylobacter has been responsible for serious outbreaks in recent years. Often these relate to consumption of non-pasteurized milk, but there are other sources reminding of the dangers and characteristic of this unique bug. Contaminated water in New Zealand, for example, resulted in more than 4,100 people contracting campylobacteriosis, including at least one fatality. An outbreak in the United States linked to the purchase of puppies showed how much of a stalwart C. jejuni can be. Nearly 100 persons from 17 states were affected – one-fourth of whom required hospitalization – and doctors realized that the particular strain of C. jejuni sickening them was exceptionally resistant to standard antibiotics.
The U.S. Department of Agriculture’s Food Safety and Inspection Service (FSIS), the regulatory body overseeing process controls for handling and microbiologic monitoring of poultry and eggs (as well as meats), is the entity with the most worldwide influence in curbing Campylobacter. Importantly, the FSIS revised its testing program for Campylobacter, as well as Salmonella, in 2016 and anticipates the changes will help prevent 50,000 illnesses from occurring per year. Since that announcement, international regulatory systems have worked to bring their frameworks into harmony.
These changes have reminded food processors of the need for easier and more effectively managed specific and sensitive detection. While isolation and detection methods have long been developed for many foods with a history of Campylobacter contamination, classic culture-based methods (agar, etc.) frequently require 4 to 6 days to get results and are hard-pressed to accurately confirm the pathogen due to the fact that samples – particularly samples in the poultry industry – can possess large, complex microbial loads.
To facilitate these changes, and in efforts to bring about continuous improvement, food producers turn to advanced technologies based on molecular (DNA or RNA) science to amplify and detect a specific gene target from organisms like Campylobacter that may be in their samples, so they can be monitored for presence and prevalence. The 3M™ Molecular Detection Assay 2 – Campylobacter, a test kit that’s applicable with the award-winning 3M™ Molecular Detection System, helps address this need by bringing greater levels of speed, simplicity and efficiency to microbiological analysis of poultry products.