The history of milk-bourne diseases

Milk Lately

by Elspeth Hay

Milk Lately

Elizabeth Cecil

Milk, raw and otherwise, and the continuing debates about its health benefits, safety and environmental impact, are inextricably linked to human history and the relatively recent industrialization of the dairy industry.  

Milk gets people riled up. Hell, milk gets me riled up.

A few months ago, newly pregnant, I got so overwhelmed with choices between raw and pasteurized, ultra-pasteurized and gently pasteurized—that I actually broke down in tears. No, it wasn’t my hormones, but that was without even getting into the cow’s hormones, or antibiotics, or what they ate, where they lived, or how they were treated. The thing is, milk is powerful. It’s the only food we humans can produce, and as author Nina Planck puts it, “It’s a children’s food. This always gets people excited.”

The fact that we have any choice in cows’ milk, however, is a relatively new phenomenon. Until April 20th, 1862—the day Louis Pasteur and Claude Bernard completed their first test of the method we now know as pasteurization—all milk was raw.

That doesn’t mean all milk was equal. Pasteur was inspired to develop his technique as a way to fight milk-borne diseases: things like typhoid fever, scarlet fever, diphtheria, septic sore throat, tuberculosis, and brucellosis, to name a few. Milk-borne illness was rampant at the time—as late as 1938, when pasteurization had already started to reduce the incidence of milk- borne disease, milk products accounted for 25 percent of all traceable food and water-borne disease outbreaks, according to Cornell University. These days, only 1% can be linked back to dairy.

So why was “milk sickness” such a problem during Pasteur’s time?

In a word: industrialization. Milk-borne disease has been going on since milk consumption began; when cows (or other milk-producing mammals, for that matter) are infected with a bacterial disease like brucellosis, they shed the bacteria through their milk. When we drink the milk, we ingest the bacteria, and if we can’t fight it, we get sick.

But prior to industrialization and the rise of urban living, most people drank milk from cows raised in small herds, on pasture, either in their own backyards or by a small-scale farmer nearby. Cows are bred for these conditions, and for the most part, they were healthy. Milk-borne disease outbreaks occurred, but they were generally small-scale and easy to trace—not worry enough to interest lawmakers and health departments.

In the mid 1800s, when people up and down the eastern seaboard of the United States started flocking from rural areas to cities, hoping to leave subsistence life behind—according to the U.S. Census Bureau, 15 percent of Americans lived in urban areas in 1850 as compared with 60 percent in 1950—milk production moved with them.

These urban dairies were nothing like country dairies. For starters, the cows had no access to pasture. Instead, in cities from New York to Cincinnati, most cows were confined indoors in crowded pens. In an effort to save money, dairy owners partnered with whiskey distilleries to feed the cows spent grains—often fed to the animals still “smoking hot,” as mid-nineteenth century clean-milk crusader Robert M. Hartley put it.

The result, not surprisingly, was sick cows and bad milk. A New York Times article from May 19, 1862, describing the scene when a herd of cows was accidentally exposed to the public during a distillery dairy fire conveys the reporter’s shock:

“There were all kinds of apologies for the cows in the lot, turned loose—long tails, short tails, stub tails, and some with no tails at all. Their appendages were [...] in every degree of decomposition. It was a pitiable and most disgusting spectacle.”

Many cows not only lost their tails— which, due to their inadequate diets, simply rotted and fell off—but also exhibited rotten or missing teeth, skin ulcers, running sores, and various other symptoms of poor health and disease.

But most consumers never saw the cows; all they got was the milk. Without some doctoring, they probably would have been disgusted with this, too, but the thin, blue “swill milk,” as it was called, was doctored with “plaster of Paris to take away the blueness, starch and eggs to thicken it, and molasses to give it the buttercup hue of honest Orange County milk,” as a 2008 article also from the New York Times put it. Not everyone was fooled, but the majority of city dwellers had no other option; they bought the inferior milk, and the distillery dairies reaped the profits.

By the late mid-1800s, in part as a result of this production system (general poor sanitation was also to blame), milk-borne disease and infant mortality in particular began to skyrocket in cities. According to historian Jacqueline Wolf, author of Don’t Kill Your Baby: Public Health and the Decline of Breastfeeding in the 19th and 20th Centuries, a widespread belief amongst immigrant and poorer mothers that their own breast milk was somehow inferior to cow’s milk meant that many infants started drinking the contaminated milk as early as two or three months after birth, long before their immune systems were fully developed.

In New York City, where distillery dairies were the most prevalent, infant mortality rates were almost 15% in 1898 according to the New York City Department of Health & Mental Hygiene. Not only that, but the department adds, “This is almost certainly an understatement,” given the incomplete reporting of neonatal deaths at the time.

Infant mortality rates in urban areas in Massachusetts around the same time were lower, but they still hovered around 9 percent in the eleven cities with a population over 20,000. (This according to a fascinating report in Volume 89 of the Boston Medical and Surgical Journal on children’s diseases, a large section of which is devoted to death by milk-borne disease.) That said, the number was well above the rural average of roughly 5%. And by the author’s estimation, “Artificial feeding has become probably the leading cause.”

Clearly, something needed to be done. And that’s where the raw-versus-pasteurized debate began. There were plenty of opinions out there, but in the public advocacy realm, you can trace reform back to two influential men: Nathan Straus, of New York City, also the founder of Macy’s department stores, and Dr. Henry Coit of Newark, New Jersey. Both men had lost infants to milk-borne diseases.

Straus was immensely wealthy. He believed that the only safe milk was pasteurized milk. He and his wife opened the Nathan Straus Pasteurized Milk Laboratory in New York City in 1892, and by the time hot summer weather—and with it spoiled, diseased milk—arrived in the city in 1893, he had opened a sterilized milk depot aimed at getting the poor safe milk at low prices. The next summer, he opened three more. Mothers in particular were ecstatic. “I am so glad,” an 1894 New York Times article quoted one woman as saying, “‘that I can get the sterilized milk for my baby. It saved the life of one of my children last year.”

Dr. Coit went another route. He was less interested in heating milk—the way he saw it, thin, diseased milk wasn’t healthy whether you sterilized it or not—and more interested in convincing dairy farmers to clean up their act. In 1893, he formed a Medical Milk Commission that worked with farmers to improve hygiene and feeding practices and then certified raw milk cleanliness. Both methods were accepted as “safe” milk for a while, but over time, Straus’ approach won out.

Economically, it’s easy to see why: Coit’s milk is said to have cost four times as much. Consumers had gotten used to cheap milk prices, and most either didn’t want to or couldn’t afford to pay more. Coit’s milk may have been nutritionally superior, but Straus’s milk was just as safe, and at 5 cents a quart, it was dirt cheap—a familiar trump card. And from a city health standpoint, certifying all milk was impractical. It was vastly easier to collect it and boil any bacteria out.

That’s the short story. Pasteurization didn’t become compulsory overnight—laws varied by city or town, and even today they still vary by state. But in Massachusetts, a third of milk was pasteurized by 1919, and by 1939, that number was up to almost 100 percent. Today, Massachusetts allows raw milk sales by certified dairies, but only if the consumer purchases the milk at the farm. In other words, it might be legal, but the government isn’t making it easy to get.

People who still share Coit’s view— that sterilized (ie pasteurized) milk isn’t as trustworthy as unheated milk from a clean, certified farm—go to great measures to get the raw stuff. I myself joined a coop three years ago to share the driving burden of getting a weekly supply of milk from the closest farm to our house in Wellfleet—a farm that is 84 miles away from where I live. I didn’t join so much because I was desperate for raw milk, but because like Coit, I wanted dairy from a farmer I felt I could trust—someone I knew was feeding the cows on pasture, someone local, someone who had pledged not to treat the cows with antibiotics or growth hormones. That farmer turned out to be a guy named Bill. We stuck with his milk because although the drive (for which our turn comes up every three or four months ) is a pain, the milk is good— un-homogenized, full fat—and for our two healthy adult bodies, never a problem in terms of illness or digestion.

Ultimately, during my pregnancy, we’ve decided to take a break from the coop. As much as I believe in the cleanliness of the raw milk we get, no cow is completely immune to disease. That’s why pasteurization came about in the first place. I tend to be cautious, and for me, pregnancy is no exception. The risk of contracting a bacterial disease like listeria—which can affect a seemingly healthy cow, which the CDC claims is some twenty times more likely to be contracted by pregnant women, and which can cause complications like premature delivery and stillbirth—is simply too scary for me. Instead, we’re getting whole pasteurized milk from a company I’ve researched extensively, a company whose milk I don’t think is quite as nutrient dense as Bill’s, but is as close in the pasteurized world as we are going to get. And in the end, that’s the thing. There are people who want raw milk. There are people who want pasteurized milk. There are circumstances where pasteurization is important in preventing disease, and circumstances in which it might not help so much. That much, history makes clear. I just hope that eventually, Massachusetts law will catch up and make buying milk more about choice and belief, and less about fear.