Officials in the United States have warned over and over again that raw, unpasteurised milk can carry dangerous and potentially deadly bacteria.

Today, however, it seems like that information is falling on deaf ears. Disease outbreaks caused by raw milk are on the rise, and a new warning from the Centres for Disease Control and Infection (CDC) has now set 19 states on high alert.

At the end of 2018, a New York resident was diagnosed with an infectious disease called brucellosis after drinking raw milk from Miller's Biodiversity farm in Pennsylvania.

Now the CDC has confirmed that this farm's raw milk did, in fact, contain a rare strain of the Brucella bacterium, RB51, which is resistant to first-line antibiotics and can be difficult to diagnose given its flu-like symptoms.

Tracing the sale of this product, investigators have found it in over a third of US states, including California, Connecticut, Florida, New Jersey, Pennsylvania, and Virginia, putting an unknown number of people at risk.

It's the third time that raw milk has caused brucellosis since 2017, when the CDC had to warn the public about the risks "for the second time in three months."

The sad thing is, these outbreaks are entirely preventable, if only people would listen.

Ever since pasteurisation was first discovered in the mid-19th century, it has been saving lives. By heating milk to a high-enough temperature, we can kill Brucella and other illness-causing germs that hide in raw milk, like bovine tuberculosis and typhoid fever, which used to claim hundreds of thousands of lives back in the day.

Nowadays, milk you will typically find in the supermarket is pasteurised to prevent dangerous bacterial growth.

Nevertheless, some people are beginning to eschew these products. Proponents of raw milk claim that pasteurised products cause allergies and contain fewer of the healthy enzymes and nutrients than raw ones.

Still, there is little scientific evidence to support either of these arguments, and most experts warn against consuming raw dairy products.

"Pasteurising milk does not cause lactose intolerance and allergic reactions," the FDA website reads.

"Both raw milk and pasteurised milk can cause allergic reactions in people sensitive to milk proteins. Pasteurisation also does not reduce milk's nutritional value."

On the other hand, the risks from raw milk are clear. Out of all the food-borne illnesses linked to dairy products, raw milk and raw cheese are responsible for no less than 96 percent.

This means that unpasteurised dairy products cause 840 times more illnesses and 45 times more hospitalisations than their pasteurised counterparts.

It isn't unheard of for people who drink raw milk to contract rare diseases, which, if they aren't treated properly, can sometimes lead to paralysis, stroke, kidney failure, and even death.

As a result, roughly half of all US states have banned the sale of raw milk; while this tactic isn't foolproof, the CDC claims that as more states allow the sale of raw milk, the number of associated outbreaks has also gone up.

From 1993 to 2012, raw milk was responsible for 127 disease outbreaks, including nearly 2,000 individual cases and 144 hospitalisations. Most of these cases were caused by Brucella, Campylobacter, certain types of E. coli, or Salmonella.

But unfortunately, in recent years, these outbreaks have started to occur more and more. According to the CDC, from 2007 to 2012, the average number of annual outbreaks linked to raw milk was four times higher than the thirteen years previous.

One particularly bad outbreak in 2010 saw 30 people hospitalised in Colorado from raw goats milk. And just last summer, a particularly nasty strain of E. coli called O157:H7 caused kidney failure in at least four victims in Tennessee.

What's worse, young children are at the highest risk. According to the CDC, 59 percent of these raw milk outbreaks involved at least one child younger than five.

In fact, kids between the ages of one and four have accounted for 38 percent of the salmonella cases and 28 percent of the E. coli cases linked to raw milk.

"These studies indicate that outbreaks from raw milk continue to threaten the public's health," the CDC concludes.

"You should only consume pasteurised milk and milk products. Look for the word "pasteurised" on product labels."