An outbreak of infections linked to McDonald’s Quarter Pounders has a lot of people across the United States concerned about their exposure to dangerous E. coli bacteria.
It is not yet known which specific food ingredient in the burgers has been contaminated, but as of Tuesday, dozens of people have gotten sick with E. coli infections, including one death, in at least 10 states, according to the US Centers for Disease Control and Prevention.
The type of bacteria that has been implicated in this outbreak is E. coli O157:H7.
“With this particular type of E coli that has been in the news – it’s called O157:H7 – the most vulnerable groups tend to be elderly adults and very young children,” said Dr. James Gaensbauer, a pediatric infectious diseases physician at Mayo Clinic Children’s Center in Rochester, Minnesota.
Although E. coli is very common and can cause a number of health problems, including urinary tract infections and stomach flu, “this particular strain mainly causes gastrointestinal symptoms including abdominal cramps, vomiting and most importantly painful diarrhea that at times can become bloody,” Dr. Marcus Pereira, an assistant clinical professor of medicine at the Columbia University College of Physicians, said in an email.
“Some people can also develop fever and eventually become dehydrated from not eating or drinking much while having diarrhea,” he said. “The good news is that, although at times it can be severe, most people with E. coli O157:H7 recover on their own.”
McDonald’s customers are encouraged to get medical care if they ate a Quarter Pounder and developed symptoms of E. coli infection.
What are the symptoms, and how is it treated?
E. coli, or Escherichia coli, is a common type of bacteria that lives in the intestines of people and animals, but some E. coli can make people sick. People can get infected after swallowing E. coli from contaminated food or water or through contact with animals, environments or other people where the bacteria present.
“Also, it occurs in clusters that might be around a particular exposure or a particular risk, and that may happen maybe every few years,” Gaensbauer said. “It’s relatively common and something that I probably treat a few times per year.”
People infected with harmful E. coli can start to notice symptoms a few days to as much as nine days after exposure to the bacteria, according to the US Food and Drug Administration. A person can be tested for the presence of E. coli in their stool.
Symptoms of infection include diarrhea, especially lasting for more than three days, and a fever higher than 102 degrees Fahrenheit. Some people may also have severe stomach cramps and vomiting.
Most healthy people may not develop symptoms, Gaensbauer said.
But “for the most part, the symptoms that people should be on the lookout for is diarrhea,” he said. “The severe kinds of diarrhea that come from E. coli can often start with a loose stool, a watery kind of diarrhea, but it will occasionally then progress to bloody diarrhea.”
Most people recover without treatment, after about a week, but some may develop serious health problems and need to be hospitalized.
“There is a particular kind of E. coli known as Shiga toxin-producing E. coli, or STEC, that has been implicated in serious foodborne illness outbreaks. Exposed individuals could get bloody diarrhea and even kidney failure,” Dr. Leana Wen, an emergency physician and professor of health policy and management at the George Washington University Milken Institute School of Public Health, said last year.
The CDC estimates that there are about 265,000 infections with Shiga toxin-producing E. coli in the United States each year.
“Treatment consists of supportive care for symptoms and fluids for hydration,” Wen added.
Infection with STEC can lead to a serious health condition called hemolytic uremic syndrome, in which kidney failure may occur, or even death. And O157:H7 is one of these types of bacteria.
“For the initial phases of E coli infection, with diarrhea, hydration is the most important treatment so individuals infected should be drinking plenty of fluids if they can tolerate it. Children are at most risk of dehydration and products such as Pedialyte are often recommended in this situation,” Pereira wrote in the email.
“Sometimes patients need IV hydration at a medical facility when they are more severely dehydrated. For E. coli O157:H7, antibiotics are controversial and are generally not recommended based on some evidence that they can actually increase the risk of hemolytic uremic syndrome,” he said.
The CDC warns against using antibiotics with STEC infections for this reason.
“The other thing that we really are careful about with this is that sometimes there are medicines that people take to slow down their bowels when they have diarrhea, and those medicines are not recommended,” Gaensbauer said. “The idea is that you maybe don’t want to keep the bacteria and the toxin in – maybe it’s better to have the diarrhea. So, people should really always consult their physician before taking any anti-diarrheal medicines if they’re worried that they have an E. coli infection.”
How to prevent E. coli infection
The best ways to prevent E. coli infections are to keep your hands clean by washing them frequently, to prepare food safely and to drink safe water, according to the CDC.
“Undercooking meat is a common and serious problem. Infectious organisms may not be killed at lower temperatures,” Wen said. Thoroughly cooking meat to an internal temperature of 160 degrees Fahrenheit throughout kills E. coli O157:H7, according to the US Department of Agriculture.
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Another way to prevent illness is to thoroughly wash vegetables and fruits before using them.
“Even if you are going to peel them, you should wash them first under running water. It’s not necessary or advisable to use soap, dishwashing liquid, disinfectants or other solutions,” Wen said.
“Be aware of what containers and utensils are in contact with raw meat. Do not put salad items or cooked meat into these containers,” she said. “Also, do not wash other uncooked meat or raw seafood in your sink. That could spread bacteria, and you could inadvertently contaminate other food.”
The CDC also notes that choosing pasteurized milk and juices can reduce the risk of E. coli exposure because the pasteurization process kills harmful germs, including E. coli.
