Taking Stock: Moo-ving to safety
Making American milk safe—Phoebe Arslanagić-Little
How good ideas spread
‘In 1887, a New Jersey toddler called John Summerfield Coit died of milk-borne diphtheria. Neither his death at such a young age nor that he contracted the disease that killed him from drinking cow’s milk was unusual. In 1880, 28.8 percent of babies in nearby New York died before their first birthday. The primary cause of this extreme infant mortality rate was infectious diseases, with milk acting as a major vector of transmission. Raw cow’s milk can carry pathogens including typhoid, diphtheria, scarlet fever, and tuberculosis. All of these were significant killers of children and adults in nineteenth-century America.
‘Raw milk was a particular threat to infants because it was common for babies to be fed partly or exclusively on cow’s milk, an ancient practice known as “artificial feeding” that grew in popularity as bottle designs improved and more mothers worked outside the home. As populations urbanized, artificial feeding became more dangerous because milk had to travel further distances. The widespread practice of adulteration increased the risk to babies. The result was very high infant mortalitywhere breastfeeding rates were lower, caused by gastrointestinal diseases and pathogens.
‘One early twentieth-century study from New York’s Bureau of Child Hygiene found that of 1,065 infant children killed by diarrheal diseases, only 16.7 percent were breastfed exclusively, with 22.7 percent fed on a mixture of dairy and breast milk, and 60.6 percent exclusively artificially fed.
Today, widespread pasteurization has made milk safe. Pasteurization, a low temperature heat treatment, was invented by French chemist Louis Pasteur in the early 1860s. But 20 years later, John Summerfield Coit and his peers were still dying of milk-borne pathogens.
Delays in understanding that milk was a vector for disease, debates over the health effects of heat-treating milk, and confusion over effective pasteurization meant it took decades for milk pasteurization to become standard in the US, at a cost of hundreds of thousands of lives.
‘. . . [G]erm theory was in its infancy in the 1860s. Instead, it was the impurity of milk due to adulteration, not pathogens, that was the focus of American health authorities as the crucial factor in making milk dangerous to children. . . .
‘A step forward in identifying the presence of pathogens in milk came in 1882, when German microbiologist Robert Koch discovered the human tuberculosis bacillus, which he named Mycobacterium tuberculosis. Koch achieved this by using a special staining method that made the bacillus visible under a microscope. . . .
‘He then injected the bacilli into guinea pigs and saw that they went on to develop the symptoms of tuberculosis.
The discovery made Koch famous. But Koch did not identify bovine tuberculosis, believing that human and bovine tuberculosis were the same disease and doubting the extent to which tuberculosis could pass from cows to humans.
‘Serious interest in pasteurizing milk did not arise until the late 1890s, when a doctor and microbiologist working for the American government, called Theobald Smith, showed that bovine tuberculosis was a distinct, though related, pathogen from human tuberculosis. Smith published a paper warning that humans could be catching bovine tuberculosis from milk.
Building on Koch’s seminal microbiology work, scientists and physicians identified more and more pathogens that could be caught from milk, which by 1900, included diphtheria, scarlet fever and typhoid.
‘But even once it was established that milk could carry dangerous diseases, there was resistance to its widespread pasteurization. In the US, take-up faced strong medical opposition from doctors, particularly pediatricians, who argued that the heating process might be making milk less nutritious and that clean, raw milk was best for infants.
‘Notable among the medical men who resisted pasteurization was Dr Henry L Coit of Newark, father of John Summerfield. . . . Coit, like many pediatricians of his day, completely dismissed pasteurization, believing it to be a dangerous red herring. He called pasteurization a “compromise for pure milk” and a way of making “dirty milk clean”. The resistance of medical men like Coit contributed to public skepticism towards pasteurization and also made dairies less likely to take up the process. Pasteurization was also somewhat counterintuitive. In this era, the safest milk was procured quickly, with as little time as possible between cow and cup. Many people believed that adding extra steps only increased the risk while worsening the taste.
‘Even as new research showed small children consuming pasteurized milk had lower rates of diarrhea and death, change was slow. Between 1890 and 1927, over 30 scientific reports were published that each recommended different temperatures and lengths of time necessary for pasteurization to kill tuberculosis. Meanwhile, milk producers were sensitive to anything that might give their product a “cooked” flavor.
‘However, others became convinced that pasteurization was the key to providing the children of America with safe milk. Key among them was philanthropist and department store magnate Nathan Straus. . . . Like Coit, Straus’s motivations in joining the fight for safer milk were personal: two of his children had died from milk-borne tuberculosis. But unlike Coit, the tragedy turned Straus into a champion for pasteurization.
‘Straus’s great project was to familiarize Americans with pasteurized milk by making it widely available to them at loss-making prices, putting to bed fears that it was an inferior product through easy access and familiarity. Inspired by a New York paediatrician who had established a heat-treated milk dispensary for children, Straus began opening up his own milk depots in 1893.
‘In sharp contrast with Coit’s expensive certified milk, produced only by select dairies, Straus’s subsidized depots sold bottles of pasteurized milk cheaply and gave them away for free to poor families. . . . In 1900, Straus’s depots distributed over half a million bottles of milk, and by 1920, Straus had established 297 milk depots in 36 different American cities. . . .
‘In 1907, President Theodore Roosevelt ordered the US Public Health Service to investigate the benefits of pasteurized milk. The resulting report was a victory for pasteurization. Surgeon General Walter Wyman wrote that it “prevents much sickness and saves many lives.” In the wake of the report, American cities’ take up of pasteurization gathered pace. By 1924, every city with a population over half a million was pasteurizing at least half its milk supply. . . .
By 1923, New York’s infant mortality rate had decreased from 28.8 percent in 1880 to 6.6 percent. Alongside other improvements, such as better sanitation, the widespread pasteurization of the city’s milk was a contributor to that happy decline.
For Coit’s part, he was undoubtedly successful in getting safer raw milk to more people, and his emphasis on refrigeration and hygiene is mirrored in many of today’s practices. But he remained essentially blind to the value of pasteurization. . . .’
worksinprogress.news | @WorksInProgMag | @PMArslanagic
Powerful CRISPR system inserts whole gene into human DNA—Nature Briefing
‘Directed’ evolution in the laboratory creates an editing tool that outperforms classic CRISPR systems.
‘A new genome-editing tool promises to insert entire genes, precisely and efficiently, into human DNA. The method uses a bacterial enzyme complex called a CRISPR-associated transposase (CAST), which can introduce full-length genes at targeted sites in a single step, without creating double-stranded breaks in DNA. Researchers used directed evolution — a process that harnesses the power of Darwinian natural selection in the lab — to produce an optimized version of the enzyme complex, called evoCAST, that showed a more than 400-fold improvement in efficiency over the non-evolved original.’
nature.com
Landmark pandemic treaty adopted despite pushback by some countries—Jenny Lei Ravelo
The treaty is designed to create a world better prepared for pandemics, ensuring a more equitable distribution of lifesaving medical interventions, a key challenge highlighted by the COVID-19 response.
‘After more than three years of wrangling, the 78th World Health Assembly adopted the long-awaited pandemic treaty this morning — a sweeping effort to fix the global failures exposed by the COVID-19 pandemic. . . .
‘The treaty aims to boost pandemic readiness and tackle inequities, but disagreements over funding, tech transfer, and sovereignty dragged talks out for years. Some countries, such as Iran and Slovakia, voiced concerns over access and human rights, with Slovakia forcing a rare vote, Devex Senior Reporter Jenny Lei Ravelo writes.
‘Still, the resolution cleared the two-thirds bar with no votes against — though there were 11 abstentions and 46 no-shows — setting the stage for formal adoption this morning. Now comes the hard part: Finalizing the pathogen access and benefit sharing system, or PABS, a key piece tying shared pathogen data to fair access to vaccines and treatments. Negotiators hope to wrap that up by May 2026.’
pages.devex.com | @devex | @JennyLeiRavelo
+ With U.S. absent, WHO adopts pandemic treaty aimed at improving vaccine access—STAT News
Countries at the World Health Assembly showed strong support for the treaty, which was negotiated over three years.
Bird-flu vaccine for cows shows promise—Nature Briefing
‘Researchers have developed the first mRNA bird-flu vaccine for cattle. Early results suggest that the vaccine triggers a strong immune response to the virus, and curbs infection in calves given milk from H5N1-infected cows—a suspected route of transmission among cattle. A widely-used vaccine for livestock could reduce the risk of animal-to-human transmission of a virus that poses a “real pandemic threat”, says virologist and study co-author Scott Hensley. He and his team are working on further trials in adult lactating cows.’
nature.com | @Nature
Why some tycoons are speeding up their charity—The Economist
Governments are doing less, but the need for aid has not diminished
‘Earlier this month Bill Gates announced that the Gates Foundation will close its doors in 2045, earlier than expected. Since it was established at the turn of the millennium the foundation has become the world’s largest, spending $100bn to fight disease and poverty. The plan is to dish out another $200bn in the next 20 years. That is virtually all of Mr Gates’s fortune. It is the latest example of a trend towards speedy giving.
‘The grandfathers of modern philanthropy—Gilded Age industrialists like Andrew Carnegie and John D. Rockefeller—set up foundations that still operate. Some of today’s wealthy are experimenting with models that get money out of the door fast. MacKenzie Scott, the ex-wife of Amazon’s founder, Jeff Bezos, has dished out more than $19bn in just a few years. In the past ten years the share of American family foundations spending down their funds has risen to 13% from 9%. Why the rush?
‘Some tycoons seem genuinely uncomfortable with their wealth. That was true of Chuck Feeney, a duty-free billionaire, who quietly gave away $8bn and closed his foundation before he died a couple of years ago. Others want to give while they’re alive in order to control how money is spent. The Ford Foundation’s decades-long feud with the founder’s family is a warning to all. It helps that the rich are minting money younger. Mr Gates, the founder of Microsoft, became a billionaire aged 31, making him the youngest one in the world at the time. Some of today’s tech bros earned their first billion in their 20s. They have time for “giving while living”.
‘Add to that a newly urgent need for funding. The Gates Foundation is trying to plug some of the gap left by government donors. America, which has historically spent more on aid than other rich countries, has gutted its aid agency. Others are slashing budgets, too. Official development assistance from the world’s largest donors dropped for the first time in six years in 2024, according to estimates from the OECD, a club of rich countries.
Mr Gates reckons there is no reason for private donors to hold back. ‘The needs are very urgent,’ he says, ‘and there will be a lot of rich people 20 years from now.’. . .
‘Mark Suzman, head of the Gates Foundation, says $200bn is a “conservative” estimate of what it will spend in the next 20 years. Not everyone is excited about donors dishing out so much so quickly. It can be hard to give effectively at full speed. In his note announcing the closure of his foundation, Mr Gates quoted Carnegie’s “The Gospel of Wealth”: “the man who dies thus rich dies disgraced.” It’s hard to think of a statement that is more joyfully counter-cultural.‘
economist.com | @TheEconomist
Arresting headlines
Sugar signalling applications could boost wheat yields by up to 12%: Long term study confirms effectiveness of new technology. Enhancing wheat plants’ sugar signalling ability could deliver increased yields of up to 12%, according to a study from Rothamsted, Oxford University and the Rosalind Franklin Institute and published today in the journal Nature Biotechnology. That is an order of magnitude greater than annual yield increases currently being achieved through breeding—Rothampsted Research (h/t Lynn Brown)
Swiss cows moo-ved to safety in landslide risk areas: Fears of a landslide in the Swiss village of Blatten saw 52 cows ‘moo-ved’ to safety, suspended in harnesses from a helicopter. As you can see, the herd appeared fairly untroubled by the whole operation, as they soared above the Alps—BBC News Briefing
