Posts about Antibiotics

Widespread Misuse by Those Who Use Antibiotics Infrequently Leads to Resistance

Widespread, occasional use of antibiotics in USA linked with resistance

The increasing prevalence of antibiotic resistance in the U.S. appears more closely linked with their occasional use by many people than by their repeated use among smaller numbers of people, according to a large new study from Harvard T.H. Chan School of Public Health.

The study also found that antibiotic use varies across the nation, and that in areas where particular antibiotics are used more frequently, resistance to those antibiotics is higher.

“We know that efforts to reduce inappropriate use of antibiotics are critical to addressing the problem of antibiotic resistance.

“Our results show that most antibiotic use is occasional—by people taking just one antibiotic course in a year—and that this occasional use is more closely linked with antibiotic resistance than intense, repeated use.”

The problems created by misuse of antibiotics are significant and continuing. The consequences are long term and diffuse. The lack of immediate and damaging impacts makes the continued misuse seem to have little consequence. However, the consequences are dire but not immediate.

In this way it is similar to the problems caused by pumping huge amounts of green house gases into the atmosphere and causing massive climate changes (though delayed by several decades). As a society we really have to get better at changing our behavior when the long term consequences are dire and clear.

It is good to learn from these efforts to understand the most significant aspects of our continued misuse of antibiotics in order to prioritize where we focus our improvement efforts.

Related: What Happens If the Overuse of Antibiotics Leads to Them No Longer Working? (2011)Our Dangerous Antibiotic Practices Carry Great Risks (2012)80% of the Antibiotics in the USA are Used in Agriculture and AquacultureCDC Urges Increased Effort to Reduce Drug-Resistant Infections (2006)Antibiotics Breed Superbugs Faster Than Expected (2010)

Learning About Bacterial Biofilms

Unlike bacterial biofilms can be visible to the naked eye. As with many instances of bacteria they are often harmless to us but when the bacteria are dangerous the biofilm offers them protection (which is why they form such structures).

Unlocking the secrets of bacterial biofilms – to use against them by Karin Sauer

The term “biofilms” suggests a thin, two-dimensional substance, but these communities feature microscopic-scale tower-like structures crisscrossed with water channels, all of which is encased in a protective, self-produced slimy layer. The bacteria within communicate and demonstrate cooperative behavior reminiscent of primitive organs.

According to the National Institutes of Health, more than 65 percent of chronic inflammatory and infectious diseases are due to biofilms. According to recent studies, biofilm-related infections claim as many lives as heart attack or cancer.

Scientists think there are several reasons for this decrease in susceptibility. First, the slimy layer encasing biofilms can make it hard for disinfectants or antimicrobials to even physically reach the bacteria. Also, bacteria living in biofilms experience high stress levels while growing rather slowly, which can render most antibiotics ineffective since they only work on actively growing cells. My favorite theory is that living in a biofilm changes bacteria and their behavior; something about their mix of active genes and proteins just makes them more resilient. Whatever the contributing factors, bacteria growing in a biofilm can be up to 1,000-fold more resistant to antibiotics than the same bacteria grown planktonically.

The use of biofilms predates our use of anti-biotics but the adaptation of forming biofilm communities serves as a protection against antibiotics and so it isn’t a surprise that with more use of antibiotics more surviving bacteria will be those using biofilm strategies.

Controlling biofilms in the future will likely require a combination of strategies, addressing both attachment and escape, with and without the use of antibiotics and communication blockers, and likely in a manner more or less tailored toward the different bacterial lifestyles.

Thankfully for us, we have many researchers exploring options to help us figure out how we can protect ourselves when we need to. We are going to need many different strategies to protect us going forward. Our success will depended on thousands of scientists working on these issues.

Related: Scientists Target Bacteria Where They Live (2009)Using Nanocomposites to Improve Dental Filling Performance (2012)Fighting Superbugs with Superhero Bugs (2015)The Search for Antibiotic Solutions Continues: Killing Sleeper Bacteria Cells (2013)

Our Poor Antibiotic Practices Have Sped the Evolution of Resistance to Our Last-Resort Antibiotic

The risk to human health due to anti-biotic resistance continues to be a huge public health concern. Our continued failure to adopt better antibiotics practices increase that risk. Those bad practices include feeding large amounts of antibiotics to farm animals to increase yields and increase the evolution of drug resistant bacteria.

Resistance to last-resort antibiotic has now spread across globe

The genes found in Denmark and China are the same, says Aarestrup, suggesting mcr-1 has travelled, rather than arising independently in each place. It is thought to have emerged originally in farm animals fed colistin as an antibiotic growth promoter.

In 2012, the World Health Organization called colistin critically important for human health, meaning its use in animals should be limited to avoid promoting resistance. Yet in 2013, the European Medicines Agency reported that polymyxins were the fifth most heavily used type of antibiotic in European livestock.

Colistin, an antibiotic that previously was a last defense against resistant strains of bacteria, is even more heavily used in China than Europe (it is not clear how the resistance developed but it likely developed in one place, most likely China, and spread rather than emerging in 2 places). The USA has been more responsible and has not risked human health through the widespread use of colistin in farm animals. But the USA still uses antibiotics irresponsibly to promote livestock growth at the risk of human lives being lost as antibiotics lose their effectiveness as bacteria evolve resistance (which is sped by poor practices in agri-business).

Antibiotic resistance is an enormous risk to human health. Millions of lives could be lost and we have have years to reduce those risks. Scientists are doing a great deal of work to find new tools to help us avoid catastrophe but we have been far too careless in our practices, especially in the massive use of antibiotics merely to boost yields in agribusiness.

Related: Are you ready for a world without antibiotics? (2010)80% of the Antibiotics in the USA are Used in Agriculture and AquacultureWhat Happens If the Overuse of Antibiotics Leads to Them No Longer Working?Waste Treatment Plants Result in Super Bacteria (2009)CDC Again Stresses Urgent Need to Adjust Practices or Pay a Steep Price (2013)

Fighting Superbugs with Superhero Bugs

As concerns over deadly antibiotic-resistant strains of ‘superbug’ bacteria grow, scientists at the Salk Institute are offering a possible solution to the problem: ‘superhero’ bacteria that live in the gut and move to other parts of the body to alleviate life-threatening side effects caused by infections.

Salk researchers reported finding a strain of microbiome Escherichia coli bacteria in mice capable of improving the animals’ tolerance to infections of the lungs and intestines by preventing wasting–a common and potentially deadly loss of muscle tissue that occurs in serious infections. If a similarly protective strain is found in humans, it could offer a new avenue for countering muscle wasting, which afflicts patients suffering from sepsis and hospital-acquired infections, many of which are now antibiotic resistant.

images of E. coli bacteria, salmonella typhimurium and burkholderia thailandensis

Salk scientists found a strain of E. coli bacteria (left) that were able to stop muscle wasting in mice infected with either Salmonella Typhimurium (center) and Burkholderia thailandensis (right). Image courtesy the Salk Institute.

“Treatments for infection have long focused on eradicating the offending microbe, but what actually kills people aren’t the bacteria themselves–it’s the collateral damage it does to the body,” says Janelle Ayres, a Salk assistant professor in the Nomis Foundation Laboratories for Immunobiology and Microbial Pathogenesis and senior researcher on the study.

“Our findings suggest that preventing the damage–in this case muscle wasting–can stave off the most life-threatening aspects of an infection,” she adds. “And by not trying the kill the pathogen, you’re not encouraging the evolution of the deadly antibiotic-resistant strains that are killing people around the world. We might be able to fight superbugs with ‘superhero’ bugs.”

Once the most powerful and revolutionary of drugs, antibiotics appear to have reached their limits, due to the ability of bacteria to rapidly evolve resistance to the medicines. The rise of antibiotic resistance presents a grave threat to people around the world, as diseases once easily controlled repel all attempts at treatment. A recent study found that up to half of the bacteria that cause infections in US hospitals after a surgery are resistant to standard antibiotics.

In the United States alone, two million people annually become infected with bacteria that are resistant to antibiotics and at least 23,000 people die each year as a direct result of these infections, according to the U.S. Centers for Disease Control.

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Teixobactin – New Antibiotic Attacks Ability of Bacteria to Build Cell Walls

New class of antibiotic could turn the tables in battle against superbugs

The antibiotic, called teixobactin, kills a wide range of drug-resistant bacteria, including MRSA and bugs that cause TB and a host of other life-threatening infections.

It could become a powerful weapon in the battle against antimicrobial resistance, because it kills microbes by blocking their capacity to build their cell walls, making it extremely difficult for bacteria to evolve resistance.

It would be great if the exciting results carried through to real world results similar to the hope. Medical research is full of promising initial results that fail to deliver, however. We are at great risk if some new miracle anti-biotic isn’t found. Many people are investigating potential solutions.

Most antibiotics are isolated from bacteria or fungi that churn out lethal compounds to keep other microbes at bay. But scientists have checked only a tiny fraction of bugs for their ability to produce potential antibiotics because 99% cannot be grown in laboratories.

Lewis’s group found a way around the problem by developing a device called an iChip that cultures bacteria in their natural habitat. The device sandwiches the bugs between two permeable sheets. It is then pushed back into the ground where the microbes grow into colonies.

Working with a Massachusetts-based company, NovoBiotic, and researchers at the University of Bonn, [Kim] Lewis’s group screened 10,000 soil bacteria for antibiotics and discovered 25 new compounds. Of these, teixobactin was the most promising.

Though promising, Lewis said that years more work lie ahead before the drug could be available. Human clinical trials could begin within two years to check its safety and efficacy, but more development would follow that.

It is wonderful to read about the great work so many scientists are making in researching potential life saving drugs. Hopefully this antibiotic will save us from what will be catastrophic harm if some new antibiotic is not available soon.

Related: Search for Antibiotic Solutions Continues: Killing Sleeper Bacteria Cells (2013)New Family of Antibacterial Agents Discovered (2009)Potential Antibiotic Alternative to Treat Infection Without Resistance (2012)

Lots of Bacteria are Always Living in Our Bodies

My response to a question on Reddit – Ask Science:

Let’s say you get infected with a bacterium that causes annoying, but totally non-dangerous symptoms. If you just try to “live with it,” will your immune system eventually kill it, or does killing bacteria require antibiotics in all cases?

Your body definitely kills lots of bacteria.

Your body also has tons of bacteria all the time (many doing much more good than they do harm). These bacteria also compete with each other.

So your “existing” bacteria kill off others all the time too (you have lots of different types of bacteria full time in your body – they often settle into niches and fight off any others , which is normally good as they are long term residents your body has learned to live with them).

Also like everything bacteria die off themselves – though if the conditions are right they are multiplying like crazy so that exceeds die off.

An astonishing number and variety of microbes, including as many as 400 species of bacteria, help humans digest food, mitigate disease, regulate fat storage, and even promote the formation of blood vessels.

According to estimates, phages destroy up to 40 percent of the bacteria in Earth’s oceans each day.

Staphylococcal food poisoning – an example of bacteria infection my body dealt with quickly.

People talk about genetics impact on getting cavities and impact of brushing and flossing well. Also the makeup of bacteria can help or hurt. If your mouth is home to certain bacteria tooth decay is less likely, home to others it is more likely. They tend to remain fairly steady (a certain makeup of bacteria will be consist for a person over the long term – not perfectly that way but tend that way). A UCLA microbiologist developed a mouthwash to try and ceed your mouth with good bacteria and oust the bad guys.

Related: People Have More Bacterial Cells than Human CellsHuman Gene Origins: 37% Bacterial, 35% Animal, 28% Eukaryotic

Lactic Acid Bacteria in Bees Counteracted Antibiotic-Resistant MRSA in Lab Experiments

13 lactic acid bacteria found in the honey stomach of bees have shown promising results as an antibiotic treatment in a series of studies at Lund University in Sweden (Open access paper: Lactic acid bacterial symbionts in honeybees – an unknown key to honey’s antimicrobial and therapeutic activities). The group of bacteria counteracted antibiotic-resistant MRSA in lab experiments. The bacteria, mixed into honey, has healed horses with persistent wounds. The formula has also previously been shown to protect against bee colony collapse.

photo of a bee on a flower

Photo by Justin Hunter

Raw honey has been used against infections for millennia, before honey – as we now know it – was manufactured and sold in stores. So what is the key to its’ antimicrobial properties? Researchers at Lund University in Sweden have identified a unique group of 13 lactic acid bacteria found in fresh honey, from the honey stomach of bees. The bacteria produce a myriad of active antimicrobial compounds.

These lactic acid bacteria have now been tested on severe human wound pathogens such as methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa and vancomycin-resistant Enterococcus (VRE), among others. When the lactic acid bacteria were applied to the pathogens in the laboratory, it counteracted all of them.

While the effect on human bacteria has only been tested in a lab environment thus far, the lactic acid bacteria has been applied directly to horses with persistent wounds. The LAB was mixed with honey and applied to ten horses; where the owners had tried several other methods to no avail. All of the horses’ wounds were healed by the mixture.

The researchers believe the secret to the strong results lie in the broad spectrum of active substances involved.

“Antibiotics are mostly one active substance, effective against only a narrow spectrum of bacteria. When used alive, these 13 lactic acid bacteria produce the right kind of antimicrobial compounds as needed, depending on the threat. It seems to have worked well for millions of years of protecting bees’ health and honey against other harmful microorganisms. However, since store-bought honey doesn’t contain the living lactic acid bacteria, many of its unique properties have been lost in recent times”, explains Tobias Olofsson.

This is a very cool: “When used alive, these 13 lactic acid bacteria produce the right kind of antimicrobial compounds as needed, depending on the threat.” As is the note that store bought honey doesn’t contain the living bacteria. My guess is some honey bought directly from farmers or bee-keepers, at farmer’s markets may well still have those live bacteria – but I am just guessing I may be wrong.

The next step is further studies to investigate wider clinical use against topical human infections as well as on animals.

The findings have implications for developing countries, where fresh honey is easily available, but also for Western countries where antibiotic resistance is seriously increasing.

Related: People are Superorganisms With Microbiomes of Thousands of SpeciesThe Search for Antibiotic Solutions Continues: Killing Sleeper Bacteria CellsOur Dangerous Antibiotic Practices Carry Great RisksPotential Antibiotic Alternative to Treat Infection Without Resistance
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80% of the Antibiotics in the USA are Used in Agriculture and Aquaculture

Citing an overabundance in the use of antibiotics by the agriculture and aquaculture industries that poses a threat to public health, economics professor Aidan Hollis has proposed a solution in the form of user fees on the non-human use of antibiotics.

In a newly released paper published (closed science, sadly, so no link provide), Hollis and co-author Ziana Ahmed state that in the United States 80% of the antibiotics in the country are consumed in agriculture and aquaculture for the purpose of increasing food production.

This flood of antibiotics released into the environment – sprayed on fruit trees and fed to the likes of livestock, poultry and salmon, among other uses – has led bacteria to evolve, Hollis writes. Mounting evidence cited in the journal shows resistant pathogens are emerging in the wake of this veritable flood of antibiotics – resulting in an increase in bacteria that is immune to available treatments.

If the problem is left unchecked, this will create a health crisis on a global scale, Hollis says.

Hollis suggest that the predicament could be greatly alleviated by imposing a user fee on the non-human uses of antibiotics, similar to the way in which logging companies pay stumpage fees and oil companies pay royalties.

“Modern medicine relies on antibiotics to kill off bacterial infections,” explains Hollis. “This is incredibly important. Without effective antibiotics, any surgery – even minor ones – will become extremely risky. Cancer therapies, similarly, are dependent on the availability of effective antimicrobials. Ordinary infections will kill otherwise healthy people.”

Bacteria that can effectively resist antibiotics will thrive, Hollis adds, reproducing rapidly and spreading in various ways.

“It’s not just the food we eat,” he says. “Bacteria is spread in the environment; it might wind up on a doorknob. You walk away with the bacteria on you and you share it with the next person you come into contact with. If you become infected with resistant bacteria, antibiotics won’t provide any relief.”

While the vast majority of antibiotic use has gone towards increasing productivity in agriculture, Hollis asserts that most of these applications are of “low value.”

“It’s about increasing the efficiency of food so you can reduce the amount of grain you feed the cattle,” says Hollis. “It’s about giving antibiotics to baby chicks because it reduces the likelihood that they’re going to get sick when you cram them together in unsanitary conditions.

“These methods are obviously profitable to the farmers, but that doesn’t mean it’s generating a huge benefit. In fact, the profitability is usually quite marginal.

“The real value of antibiotics is saving people from dying. Everything else is trivial.”

While banning the use of antibiotics in food production is challenging, establishing a user fee makes good sense, according to Hollis.

Such a practice would deter the low-value use of antibiotics, with higher costs encouraging farmers to improve their animal management methods and to adopt better substitutes for the drugs, such as vaccinations.

Hollis also suggests that an international treaty could ideally be imposed. “Resistant bacteria do not respect national borders,” he says. He adds that such a treaty might have a fair chance of attaining international compliance, as governments tend to be motivated by revenue collection.

Hollis notes that in the USA, a move has been made to control the non-human use of antibiotics, with the FDA recently seeking voluntary limits on the use of antibiotics for animal growth promotion on farms.

Related: Raising Food Without AntibioticsOur Dangerous Antibiotic Practices Carry Great RisksWhat Happens If the Overuse of Antibiotics Leads to Them No Longer Working?Antibiotics Too Often Prescribed for Sinus Woes

Search for Antibiotic Solutions Continues: Killing Sleeper Bacteria Cells

Killing Sleeper Cells and Superbugs with Assassin Janitors

Discovered in 2005 by scientists from Bayer Healthcare in Germany, ADEP4 killed a variety of different bacteria and cured lethal infections in mice and rats.

Here’s how it works. Proteins need to fold into very precise shapes to do their jobs, and misfolded proteins are wastes of space. Bacteria dispose of these useless molecules with ClpP—a janitorial protein that digests other proteins. It works with a partner, which recognises misfolded proteins, unfolds them, and threads them through a hole in the middle of ClpP so they can be broken down. But ADEP4 opens ClpP up so it no longer needs its partner. The janitor now becomes an assassin, running amok and chopping up any protein it comes across, misfolded or not.

The Bayer scientists showed that ADEP4 can force fast-growing cells to self-destruct, but Lewis suspected that it would do the same to persisters. Afterall, ClpP’s partner requires energy to do its job, but ClpP itself doesn’t. Once ADEP4 opens it up, it should go about its fatal business even in a dormant cell.

Lewis’ team found that ADEP4 did effectively kills persister populations of Staphylococcus aureus, but the bacteria bounce back. ClpP isn’t essential, so the bacteria just inactivated it to evolve their way around ADEP4. This, says Lewis, is why Bayer stopped working on the drug.

His solution was to pair ADEP4 with another antibiotic called rifampycin. ADEP4 would kill off the majority of the persisters, and if any of the rest started growing again, rifampycin would finish them off. He predicted that the double-whammy would leave very few survivors, maybe just a thousand cells or so.

“That’s not what we saw,” he says. “What we saw was complete sterilisation.”

This is a very nice effort. As our efforts fail to find “magic bullet” antibiotics fail and antibiotic resistance increases combo drug solutions offer some hope. While this is good news, the overall state of our ability to treat bacterial infections continues to decline as our misuse of antibiotics has greatly increased the speed at which antibiotic resistance has developed in bacteria.

This solution only works on gram positive antibiotics. ADEP4 is too big to pass through the extra outer layers of the gram-negative bacteria like ecoli and salmonella.

Related: Entirely New Antibiotic Developed, Platensimycin (2006) (2013 update: Platensimycin is a very effective antibiotic in vivo when continuously administered to cells, however this efficacy is reduced when administered by more conventional means. Efforts continue to find a way to create delivery options that are successful in treating people.) – New Family of Antibacterial Agents Discovered (2009)Potential Antibiotic Alternative to Treat Infection (2012)

CDC Again Stresses Urgent Need to Adjust Practices or Pay a Steep Price

Untreatable and hard-to-treat infections from Carbapenem-resistant Enterobacteriaceae (CRE) germs are on the rise among patients in medical facilities. CRE germs have become resistant to all or nearly all the antibiotics we have today. Types of CRE include Klebsiella pneumoniae Carbapenemase (KPC) and New Delhi metallo-beta-lactamase (NDM). By following the United States Center for Disease Control (CDC) guidelines, we can slow the penetration of CRE infections in hospitals and other medical facilities and potentially spread to otherwise healthy people outside of medical facilities.

The CDC has worked with hospitals to successfully apply these measures. The CDC worked with Florida to stop a year-long CRE outbreak in a long-term acute care hospital. With the improved use of CDC recommendations (such as educating staff; dedicating staff, rooms, and equipment to patients with CRE; and improving use of gloves and gowns) the percentage of patients who got CRE at the facility dropped from 44% to 0.

One travesty has been how poorly health care professionals have been about prescribe antibiotics wisely We need to improve and follow CDC antibiotics guidelines (stop the overuse of antibiotics) and use culture results (for patients undergoing treatment) to modify prescriptions, if needed. Antibiotic overuse contributes to the growing problems of Clostridium difficile (c-diff) infection and antibiotic resistance in healthcare facilities. Studies indicate that nearly 50% of antimicrobial use in hospitals is unnecessary or inappropriate (per CDC web site).

Israel decreased CRE infection rates in all 27 of its hospitals by more than 70% in one year with a coordinated prevention program. The USA is at a critical time in which CRE infections could be controlled if addressed in a rapid, coordinated, and consistent effort by doctors, nurses, lab staff, medical facility leadership, health departments/states, policy makers, and the federal government.

As I have been saying for years the damage we are creating due to our actions around the use and abuse of antibiotics is likely to kill tens of thousands, or more people. Because the deaths are delayed and often not dramatic we have continued dangerous practices for years when we know better. It is a shame we are condemning so many to increased risks. The CDC, and others, are doing good work, unfortunately too much bad work is continuing in the face of evidence of how dangerous that is.

Related: CDC Urges Increased Effort to Reduce Drug-Resistant Infections (2006)Key scientific articles on Healthcare Associated Infections via CDCOur Dangerous Antibiotic Practices Carry Great RisksDangerous Drug-Resistant Strains of TB are a Growing Threat

Antibiotics fuel obesity by creating microbe upheavals

Antibiotics fuel obesity by creating microbe upheavals

We aren’t single individuals, but colonies of trillions. Our bodies, and our guts in particular, are home to vast swarms of bacteria and other microbes. This “microbiota” helps us to harvest energy from our food by breaking down the complex molecules that our own cells cannot cope with. They build vitamins that we cannot manufacture. They ‘talk to’ our immune system to ensure that it develops correctly, and they prevent invasions from other more harmful microbes. They’re our partners in life.

What happens when we kill them?

Farmers have been doing that experiment in animals for more than 50 years. By feeding low doses of antibiotics to healthy farm animals, they’ve found that they could fatten up their livestock by as much as 15 percent.

Ilseung Cho from the New York University School of Medicine has confirmed that hypothesis. By feeding antibiotics to young mice, he has shown that the drugs drastically change the microscopic communities within their guts, and increase the amount of calories they harvest from food. The result: they became fatter.

I continue to believe we are far to quick to medicate. We tremendously overuse anti-biotis and those costs are huge. They often are delays and systemic and given our current behavior we tend to ignore delayed and systemic problems.

The link between the extremely rapid rise in obesity and the overuse of anti-biotics is in need of much more study. It seems a possible contributing factor but there is much more data needed to confirm such a link. And other factors still seem dominant to me: increase in caloric intake and decrease in physical activity.

Related: Science Continues to Explore Causes of Weight GainWaste from Gut Bacteria Helps Host Control WeightHealthy Diet, Healthy Living, Healthy WeightRaising Our Food Without Antibiotics