Back in 2006, when her son Chris was just 7 years old, Mary McGonigle-Martin thought raw milk might be a more healthful alternative to pasteurized milk for her family.
Labor Day weekend of that year, Chris drank raw milk -- and ultimately ended up in the hospital for 2 months, severely ill from an infection with Shiga toxin-producing E. coli.
"Every morning, I have to look in the mirror and deal with the fact that I almost killed my son when I made the decision to give him raw milk," McGonigle-Martin , confirming the story to ľֱ.
As more states legalize the sale of unpasteurized milk -- Iowa is -- public health experts are sounding alarms about the dangers of raw milk and how it's particularly risky for children.
A by Megin Nichols, DVM, MPH, deputy director of the CDC Division of Foodborne, Waterborne, and Environmental Diseases, and colleagues found that outbreaks linked with unpasteurized milk over a 5-year period disproportionately affected younger people. Almost half of the illnesses (48%) occurred in people age 19 and under, they found.
"We know that children are at greater risk for severe infections, and they might not make dietary decisions for themselves," Nichols told ľֱ. "We are very concerned about the risk of hemolytic uremic syndrome [HUS] due to Shiga toxin-producing E. coli that can severely affect children."
McGonigle-Martin's son that caused kidney failure. He also developed congestive heart failure, acute pancreatitis, and seizures. Chris had to be put on a ventilator and needed dialysis and blood transfusions, as well as surgery, his mother said.
He recovered, but it took a few years for Chris to get back to normal, she said.
McGonigle-Martin is now a board member of , an advocacy group that works to prevent food-related illness and death. Her goal is to spare other parents from going through what she did.
"We live in a time when we are far removed from the horrors of unpasteurized milk," she said.
Pasteurization, like vaccination, is a technology that can be taken for granted, as it's difficult to see the consequences of a world without these life-saving public health innovations.
Pasteurization is the process of heating milk to a high enough temperature, for a long enough period of time, to kill illness-causing bacteria. It was developed at a time when "millions of people became sick and died of diseases like tuberculosis, scarlet fever, typhoid fever, and other infections that were thought to be transmitted [in part] through consumption of raw milk," Nichols told ľֱ.
Implemented in the U.S. in the early 20th century, pasteurization led to "dramatic reductions" in disease and infant mortality previously associated with unpasteurized milk consumption, and it remains the best way to eliminate disease-causing bacteria in milk, she said. "It's considered one of the greatest public health achievements that we have, because it provides a source of nutrition without the germs."
For their study, Nichols and colleagues analyzed data from the CDC Foodborne Disease Outbreak Surveillance System (FDOSS), which is part of its National Outbreak Reporting System (NORS). It collects data from state, local, and territorial health departments.
From 2013 to 2018, there were 75 outbreaks tied to unpasteurized milk, totaling 675 illnesses. The vast majority of outbreaks (78%) occurred in states that allowed sales of unpasteurized milk. Indeed, jurisdictions where sales were allowed had about a three-fold higher number of outbreaks, and about a three-fold greater number of outbreak-associated illness compared with those where sales were prohibited, they reported.
A study that Nichols and colleagues cited in their paper estimated that the incidence of outbreaks involving unpasteurized dairy products was about per pound of dairy product consumed than the incidence involving pasteurized products. Another study found unpasteurized dairy products over a 5-year period, translating to about 840 times more illness and 45 times more hospitalizations than pasteurized products.
"Even though only 1% to 2% of the U.S. population is consuming [raw milk], the amount of illness in that population is very, very high, leading us to put unpasteurized milk on our list of food products that are very risky," Nichols told ľֱ.
Nichols and colleagues' paper noted that Campylobacter was the pathogen responsible for most of the reported outbreaks and outbreak-associated illnesses related to unpasteurized milk. Others included Shiga toxin-producing E. coli, Listeria monocytogenes, Salmonella, and Brucella, she said.
Researchers at the FDA Center for Food Safety and Applied Nutrition recently attempted to quantify the rate of contamination of raw milk. A of studies from a nearly 20-year period found average prevalences for the following bacteria in raw milk samples:
- Campylobacter: 6%
- Shiga toxin-producing E. coli: 4.3%
- Listeria monocytogenes: 4.3%
- Salmonella: 3.6%
While the FDA researchers declined an interview with ľֱ, FDA spokesperson Taryn Webb said in an email that the agency " the use of pasteurization of milk products," adding that the bacteria in raw milk "can be especially dangerous to people with weakened immune systems (such as transplant patients and individuals with HIV/AIDS, cancer, and diabetes), children, older adults, and pregnant women."
Nichols echoed that the risk is highest for those groups, but noted that "people of any age can get sick or die from drinking unpasteurized milk."
She added that kids aren't necessarily making dietary decisions for themselves, so it's important to educate parents about the risks of raw milk. She said sometimes people assume that improved management and sanitization practices mean these products are safer than in the past.
"If you think about the location of where manure comes from in the cow, it's directly over the udder," Nichols said. "So in terms of gravity, there is a significant chance that cow feces are coming into direct contact with the udder, and then through milking, there can be contamination of milk with cow feces."
Mastitis in the animals' teats could also contaminate the milk, and other threats in the environment, including dirty processing equipment, rodents, and insects, can add to contamination risk, Nichols said.
She added that research has shown pasteurization "doesn't significantly alter the nutritional content of the milk," and that any perceived health benefits would be outweighed by risks of contamination.
For its part, the CDC will continue to keep tabs on raw milk-associated illness through its strong partnerships with state and local health departments, Nichols said.