Want to keep these uninvited guests away from your Thanksgiving dinner? Find out how below!
With the implementation of the Food Safety Modernization Act of 2011 (FSMA), food safety practices are undergoing their largest re-haul since the Food, Drug and Cosmetic Act of 19381. FSMA has provided much needed updates to food safety practices, an emphasis on traceability, and a large focus on produce. However, FSMA will change the farming and food industry as a whole. The poultry industry, where most of the Kathariou Lab’s Campylobacter isolates come from, may also be effected. To understand how FSMA will affect the poultry industry one has to understand FSMA. It is also important to keep in mind that meat, poultry, and eggs are covered under the USDA so FSMA (which effects the FDA) will not effect them directly. However, the effects of FSMA will ripple into all parts of the food industry so these kinds of changes might take place in the USDA several years down the road.
If you have read What is Campylobacter, you will know that it is a top five foodborne pathogen for illness, hospitalization, and death. With that being the case it is remarkable that Campylobacter is still an relatively unknown pathogen. However, there are a few reasons for this including the self-limiting and sporadic nature of the disease, and under reporting of illnesses.
Campylobacteriosis most often occurs as a sporadic illness i.e. a common source for an outbreak is not noted. This tends to draw less attention from both the media and government agencies than the large multi-state outbreaks that we sometimes hear about. However, larger outbreaks of Campylobacter can occur and are often the result of unpasteurized milk or untreated water.
Campylobacteriosis is also known as being a relatively minor illness. This is true in the sense that most people will recover from their gastrointestinal discomfort without needing to see a doctor. However, illness can also be extremely acute with the pains sometimes mimicking appendicitis. Campylobacter also has the potential of causing more serious infections in the very young, old, pregnant, or immunocompromised. After a Campylobacter infection there is the potential for autoimmune complications such as Guillain-Barré syndrome, a form of reversible paralysis. Those suffering from Guillain-Barré may take months to recover and may require respiratory support. Another autoimmune complication that can follow a Campylobacter infection is reactive arthritis, characterized by painful joints, eye, and urinary tract problems.
Finally, under reporting is another contributor as to why this disease is not discussed more. Because most healthy adults will recover on their own, it is estimated that only about 1 in 31 cases is reported. Many patients do not seek medical care. Even if a patient does seek medical attention, it is not guaranteed that the doctor will perform a culture-based diagnosis. So, there may not be a definitive conclusion as to what caused the illness. Doctors may treat a patient based on one’s symptoms, and because the symptoms of Campylobacter are nearly indistinguishable from other agents that may cause gastroenteritis e.g., diarrhea and/or cramping, doctors may prescribe antibiotics that may not be optimal for treating campylobacteriosis.
It is likely that Campylobacter infections occur much more often than reported. Because the illness can be mild and of relatively short duration patients do not always seek medical care. However, even if they do it is not guaranteed that a specific etiologic agent will be identified. And, because large outbreaks are rare the media does not give this pathogen the same coverage as others which may cause more severe illness or larger outbreaks. But, because of the high number of illnesses, and the potential for severe infections and autoimmune sequelae Campylobacter should be treated as a much more important foodborne pathogen.
My name is Paige and I am a senior in Microbiology at North Carolina State University. I have been doing research in Dr. Kathariou’s lab since February of 2016. So far, my experience has been invaluable for my future career, and has made me much more excited about my future in microbiology. It is one thing to take classes and occasionally work in a lab environment, but having my own experiments to work on makes the results that much more rewarding. I enjoy lab classes, but they do not give any freedom to be creative or alter experiments if they are not working. The instructors and students already know what will happen. This is not always the case in a real lab setting.
Doing research in a lab outside of the classroom has given me the opportunity to learn how to make various types of agar, how to use an autoclave, and the correct techniques to keep everything sterile. In lab classes we always have the agar plates already made for us. Other skills I have learned include spot plating, DNA purification, how to use and interpret NanoDrop results, perform PCR, and how to work with Campylobacter and Listeria.
Although working with Campylobacter has been very fascinating, I find it much trickier than other bacteria I have worked with. Experiments do not always go as planned. Because of this I feel much more prepared for a real lab environment in terms of expectations of results, problem solving, and creative thinking. For example, we have performed various transformation experiments with Campylobacter. The goal was to transform 800 base pairs of PCR amplicon from erythromycin resistant strains to susceptible strains. We did this by adding PCR product or genomic DNA from resistant strains directly to susceptible strains. This experiment has been especially interesting because we have been able to transform using genomic DNA, but the PCR fragments have not worked yet.
One of my favorite experiments to date is a competitive fitness assay. This involves the inoculation of chicken skin fragments with various Campylobacter strains. After counting the resulting plates I then make graphs to quantify the results. This has been one of the first times I have had to make such detailed reports in Excel. So far, we have found that there is not a measurable difference between strain survival over the time points we are measuring. So, our next attempt will be to lengthen the time between measurements.
I would like to thank the amazing people that work in the lab with me, especially Kshipra who has been a fantastic mentor. I came to the lab with minimal experience and not much knowledge on Campylobacter, and was a bit nervous starting out. However, I have learned so many techniques. The lab members happily help whenever I have questions or need some guidance on experiments. I am very happy with my choice to do research in the Kathariou lab and am excited to see what my future holds.
Recently, USDA-FSIS released performance standards for Campylobacter and Salmonella requiring producers to limit the presence of these bacteria on raw poultry products1. One of the best ways to meet the Campylobacter standards is to raise flocks free of this organism. However, there are a number of reasons why it is difficult to produce Campylobacter-free birds. Campylobacter can be naturally found in the intestinal tract of birds and is easily spread via fecal contamination. As birds move around a poultry house, they may sample other birds’ droppings. Thus ingesting Campylobacter and becoming carriers. Usually, once one bird becomes colonized with Campylobacter it does not take very long for the rest of the flock to become colonized as well. The litter, feces, communal water and insects (e.g. flies) in a poultry house are all possible routes of transfer among the birds.
Growers use a number of strategies to keep the birds free of Campylobacter and other human pathogens, as well as microbes that could make the birds sick. Rodents are known carriers of Campylobacter so growers keep the areas around the poultry houses free of tall grass and debris. Doing so eliminates areas where rodents can hide or build nests. Growers have additional pest control measures in place within the poultry houses. Additionally, flies and other insects can also carry Campylobacter as well as other undesirable microbes so fly bait, insecticides, and litter treatments are used to limit their populations. Growers also wear overalls and plastic overboots so they do not track Campylobacter into the houses from the outside.
As previously mentioned, communal water and litter may play a role in spreading Campylobacter through a flock. To prevent this, the water is generally sanitized via chlorination or acidification to reduce Campylobacter or other pathogens. Campylobacter is known to be a rather fragile organism that does not tolerate oxygen or dry conditions well. Growers till the litter in the poultry houses, which helps to both oxygenate and dry out the litter making it less hospitable to Campylobacter.
At slaughter, there are a number of steps to prevent Campylobacter from being present on the raw, finished product. Externalizing the internal organs for FSIS inspection can result in microbes from the intestine contaminating the carcass. Removal of the intestines can also result in feces (and the bacteria in the feces) to leak onto the carcass. Any intestinal microbes, including Campylobacter can contaminate the carcass at this point. Because bacteria are invisible to the naked eye, all birds are potentially contaminated with Campylobacter and from this point on go through a number of decontamination procedures. To ensure the safety of the product, the carcasses get washed and may be sprayed with organic acids or other compounds that have antimicrobial action. Next, the carcasses are chilled quickly either in ice water or cold air to prevent remaining bacteria from growing and increasing in number. Chlorine may be added to the chill water to reduce microbial levels, including Campylobacter. After this step, the birds are sealed in packages and are shipped to retail.
Even though the government and food industries work together to provide safe food, poultry is still one of the more common vehicles of foodborne illness2. This makes the correct handling of raw poultry a critical step in preventing foodborne illness. You can visit check out the USDA’s tips on preventing cross contamination. By using correct thawing procedures, keeping raw poultry separate from ready-to-eat foods, and washing hands we all can help decrease the chances of becoming ill.
This is perhaps my favorite campaign to raise awareness about Campylobacter. A man in a pink chicken suit runs around ruining others’ summer activities as a reminder that nothing ruins a good BBQ like a couple of cases of campylobacteriosis. Remember that cross-contamination after handling raw poultry is a big risk factor for getting this food-borne illness. After you touch raw poultry wash your hands. As Campylobacter researchers it is also nice to see Campy getting some attention. We hope that this campaign will help to make Campylobacter a better known food borne pathogen. We recently posted an article on some of the reasons why Campylobacter isn’t better known if you would like to check that out.
An update to the previously reported Campylobacter outbreak!
Food Safety News reports that the restaurant implicated in last month’s Campylobacter outbreak is being sued by two individuals who tested positive for the bacterium just days after dining at the restaurant. The results from cooked food samples taken from the restaurant will likely not come back until July the report states, but we will try our best to report them when they do.
Usually Campylobacter causes sporadic cases of illness, so having an outbreak is unusual and interesting for Campylobacter researchers. The article, from Food Safety News, states that the cause of the outbreak is still unknown.
“County health officials are not certain what food item might have caused the illnesses. They are still checking samples of cooked foods taken from the restaurant on June 8 and also continuing to investigate the reports of those sickened.”
Poultry, unpasteurized milk, and untreated water are the most common vehicle for Campylobacter transmission. Additionally, cheeses made from raw milk can be sources of infection. While the researchers are testing the cooked food, we also hope that the raw ingredients are being tested as well.