Unpasteurised milk dangers

Consumers are again being reminded of the importance of avoiding unpasteurised milk.

According to the Food Safety Authority, raw milk – i.e. milk that is unpasteurised – can contain harmful bacteria that increase the risk of foodborne illnesses.

It has just published a report which contains the findings of a survey that confirms the presence of pathogens in raw milk and the filters used in milking equipment.

Among milk samples, detection rates of Campylobacter – the most common cause of bacterial gastroenteritis in Europe – were 3%. However, detection rates among milk filter samples were 22%.

Detection rates of Listeria monocytogenes – another bacteria that causes food poisoning – in milk samples was 7%, but 20% in milk filter samples.

Meanwhile, Salmonella was detected in 1% of raw milk filters and 0.5% of raw milk samples, while E.coli was found in 6% of raw milk filters.

“Almost all milk on sale in Europe is pasteurised and pasteurisation is the simplest and most reliable method to ensure that milk is safe to drink. While the market for raw milk is small, it remains a serious concern given the well-documented public health risks posed by the presence of pathogens in raw milk,” commented Dr Wayne Anderson of the FSA.


He recommended that raw milk should be avoided by consumers.

“For those who still wish to drink it, they should, at a minimum, boil the milk before drinking it to kill any potentially harmful bacteria,” Dr Anderson said.

He emphasised that there is an ongoing risk to farm families who continue to drink raw milk in their own homes.

“The FSA is aware that any ban on the sale of raw milk would not affect those farm families who choose to consume raw milk. But these families should be particularly aware of the risk to young children and pregnant women posed by drinking raw milk and also the fact that farm visitors may not be aware that they are consuming raw milk. We therefore continue to recommend the use of home pasteurisers to ensure milk is safe,” he commented.

Dr Anderson added that while hygiene on farms and animal health have both improved significantly in recent years, farms are still a ‘significant reservoir for pathogens’, and even with the best hygiene standards, contamination is possible.

New antibiotic discovered

A new type of antibiotic has been discovered which could be the first of a class that can effectively kill bacteria while avoiding resistance, scientists have announced.

The research, documented in the journal Nature, could signal the end of a long period in which no new antibiotics have made their way into hospitals and GP surgeries.

Antibiotics resistance is a growing health threat because the existing armoury of medication is steadily being undermined by bugs that have adapted to their destructive properties, while new drugs cannot be produced fast enough to fill the gaps.

The scenario has led to fears that in the future doctors will lack effective treatments against infections that today can be routinely cured.

The scientists say the new drug called teixobactin is effective against Clostridium difficile, Mycobacterium tuberculous and Staphylococcus aureus, and while it is hard to determine if and when resistance will set in, it may have a useful life of at least 30 years and possibly a lot longer.

Widespread introduction of antibiotics in the 1940s, most notably with penicillin and streptomycin, revolutionised medicine, taming many hitherto life-threatening diseases such as tuberculosis.

However, antibiotics have a limited shelf-life because of the way bacteria can evolve to become resistant to them. Since the 1960s this has been developing into a global health crisis.

The first antibiotics were developed by isolating compounds from soil microorganisms, but only about 1% of these can be grown under laboratory conditions. The rest are uncultured. Attempts to replicate this process synthetically have been met with limited success.

The new method uses a technique to harness those soil microorganisms that cannot be grown in the lab by placing them in special chambers in a device called an iChip and allowing them to develop in their natural environment – soil. “Once they’ve formed colonies, then with high probability they will be able to grow on regular petri dishes,” explains Professor Kim Lewis from Northeastern University in Boston.


Professor Lewis and colleagues have screened 10,000 compounds isolated from uncultured soil bacteria in their search. “So far 25 new antibiotics have been discovered by this method,” he says, “and teixobactin, the compound we’re discussing today, is the latest and the most promising one”.

Professor Lewis says the lack of resistance to the compound is “intriguing” and may be due to the way it targets bacteria.

Teixobactin has been shown to attack two specific targets in the cell walls – a novel strategy that may give it its ability to dodge resistance.

“Destruction of the material cell envelope, finally leads to cell death,” says co-author Tanja Schneider of the University of Bonn.

Patents on the iChip and related technology are owned by NovoBiotic Pharmaceuticals, based in Cambridge, Massachusetts, in the US.

Experiments so far have taken place using mice and no human trials of the new antibiotic have yet happened. “My estimate is that we will probably be in clinical trials 2 years from now,” says Professor Lewis. “This is a promising source in general of antibiotics and has a good chance of helping revive the shield of antibiotic discovery,” he adds.