The World Health Organization has made a list of the most dangerous antibiotic-resistant bacteria

National Institute of Allergy and Infectious Diseases (NIAID)

For the first time ever, the World Health Organization has drawn up a list of the highest priority needs for new antibiotics — marching orders, it hopes, for the pharmaceutical industry.

The list, which was released Monday, enumerates 12 bacterial threats, grouping them into three categories: critical, high, and medium.

"Antibiotic resistance is growing and we are running out of treatment options. If we leave it to market forces alone, the new antibiotics we most urgently need are not going to be developed in time," said Dr. Marie-Paule Kieny, the WHO's assistant director-general for health systems and innovation.

"The pipeline is practically dry."

Three bacteria were listed as critical:

• Acinetobacter baumannii bacteria that are resistant to important antibiotics called carbapenems. These are highly drug resistant bacteria that can cause a range of infections for hospitalized patients, including pneumonia, wound, or blood infections.

U.S. Centers for Disease Control and Prevention

• Pseudomonas aeruginosa, which are resistant to carbapenems. These bacteria can cause skin rashes and ear infectious in healthy people but also severe blood infections and pneumonia when contracted by sick people in the hospital.

• Enterobacteriaceae that are resistant to both carbepenems and another class of antibiotics, cephalosporins. This family of bacteria live in the human gut and includes bugs such as E. coli and Salmonella.

Notably missing from the list is the bacterium that causes tuberculosis. That was not included, Kieny said, because the need for new antibiotics to treat it has already been designated the highest priority.

Although mounting concerns about the worsening problem of antibiotic resistance have reinvigorated research efforts, producing new antibiotics is an expensive and challenging task.

The international team of experts who drew up the new list urged researchers and pharmaceutical companies to focus their efforts on a type of bacteria known as Gram negatives. (The terminology relates to how the bacteria respond to a stain — developed by Hans Christian Gram — used to make them easier to see under a microscope.)

Dr. Nicola Magrini, a scientist with the WHO's department of innovation, access and use of essential medicines, said pharmaceutical companies have recently spent more efforts trying to find antibiotics for Gram positive bacteria, perhaps because they are easier and less costly to develop.

Microscopic image of gram-negative Pseudomonas aeruginosa bacteria (pink-red rods) Credit: wikipedia

Gram negative bacteria typically live in the human gut, which means when they cause illness it can be serious bloodstream infections or urinary tract infections. Gram positive bacteria are generally found outside the body, on the skin or in the nostrils.

Kieny said the 12 bacteria featured on the priority list were chosen based on the level of drug resistance that already exists for each, the numbers of deaths they cause, the frequency with which people become infected with them outside of hospitals, and the burden these infections place on health care systems.

Paradoxically, though, she and colleagues from the WHO could not provide an estimate of the annual number of deaths attributable to antibiotic-resistant infections. The international disease code system does not currently include a code for antibiotic-resistant infections; it is being amended to include one.

The critical pathogens are ones that cause severe infections and high mortality in hospital patients, Kieny said. While they are not as common as other drug-resistant infections, they are costly in terms of health care resources needed to treat infected patients and in lives lost.

Six others were listed as high priority for new antibiotics. That grouping represents bacteria that cause a large number of infections in otherwise healthy people. Included there is the bacteria that causes gonorrhea, for which there are almost no remaining effective treatments.

Three other bacteria were listed as being of medium priority, because they are becoming increasingly resistant to available drugs. This group includes Streptococcus pneumoniae that is not susceptible to penicillin. This bacterium causes pneumonia, ear and sinus infections, as well as meningitis and blood infections.

The creation of the list was applauded by others working to combat the rise of antibiotic resistance.

"This priority pathogens list, developed with input from across our community, is important to steer research in the race against drug resistant infection — one of the greatest threats to modern health," said Tim Jinks, head of drug-resistant infections for the British medical charity Wellcome Trust.

"Within a generation, without new antibiotics, deaths from drug-resistant infection could reach 10 million a year. Without new medicines to treat deadly infection, lifesaving treatments like chemotherapy and organ transplant, and routine operations like caesareans and hip replacements, will be potentially fatal."

The full list is:

Priority 1: Critical

1. Acinetobacter baumannii, carbapenem-resistant

2. Pseudomonas aeruginosa, carbapenem-resistant

3. Enterobacteriaceae, carbapenem-resistant, ESBL-producing

Priority 2: High

4. Enterococcus faecium, vancomycin-resistant

5. Staphylococcus aureus, methicillin-resistant, vancomycin-intermediate and resistant

6. Helicobacter pylori, clarithromycin-resistant

7. Campylobacter spp., fluoroquinolone-resistant

8. Salmonellae, fluoroquinolone-resistant

9. Neisseria gonorrhoeae, cephalosporin-resistant, fluoroquinolone-resistant

Priority 3: Medium

10. Streptococcus pneumoniae, penicillin-non-susceptible

11. Haemophilus influenzae, ampicillin-resistant

12. Shigella spp., fluoroquinolone-resistant

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The above post is reprinted from materials provided by Businessinsider . Note: Materials may be edited for content and length.

This fascinating periodic table shows the origin of each atom in the human body. "We are made of stardust"

Credit: Jennifer Johnson

Here’s something to think about: the average adult human is made up of 7,000,000,000,000,000,000,000,000,000 (7 octillion) atoms, and most of them are hydrogen - the most common element in the Universe, produced by the Big Bang 13.8 billion years ago.

The rest of those atoms were forged by ancient stars merging and exploding billions of years after the formation of the Universe, and a tiny amount can be attributed to cosmic rays - high-energy radiation that mostly originates from somewhere outside the Solar System.

As astronomer Carl Sagan once said in an episode of Cosmos, "The nitrogen in our DNA, the calcium in our teeth, the iron in our blood, the carbon in our apple pies were made in the interiors of collapsing stars. We are made of stardust."

To give you a better idea of where the ingredients for every living human came from, Jennifer A. Johnson, an astronomer at the Ohio State University, put together this new periodic table that breaks down all the elements according to their origin:

Jennifer Johnson

To keep things relevant for the human body, Johnson explains that she cut a number of elements from the bottom section.

"Tc, Pm, and the elements beyond U do not have long-lived or stable isotopes. I have ignored the elements beyond U in this plot, but not including Tc and Pm looked weird, so I have included them in grey," Johnson explains on her blog with the Sloan Digital Sky Survey.

The new periodic table builds on work Johnson and her colleague, astronomer Inese Ivans from the University of Utah, did back in 2008 - a project born out of equal measures of frustration and procrastination.

"This is what happens when you give two astronomers, who are tired of reminding everyone about which elements go with which process on a periodic table, a set of markers, and time when they should have been listening to talks," Johnson admits.

The periodic table works by identifying the six sources of elements in our bodies, and breaks them down into the processes in the Universe that can give rise to new atoms: Big Bang fusion; cosmic ray fission; merging neutron stars; exploding massive stars; dying low mass stars; and exploding white dwarf.

The way the corresponding colours fill up the boxes of elements shows roughly how much of that element is the result of the various cosmic events.

So you can see that elements like oxygen (O), magnesium (Mg), and sodium (Na), resulted from gigantic explosions of massive stars called supernovae, which occur at the end of a star's life, when it either runs out of fuel, or accumulates too much matter.

The incredible amount of energy and neutrons this releases allows elements to be produced - a process known as nucleosynthesis - and distributed throughout the Universe.

Old favourites like carbon (C) and nitrogen (N), on the other hand, exist mostly thanks to low-mass stars ending their lives as white dwarfs. 

Strange elements boron (B) and beryllium (Be), and some isotopes of lithium (Li) are unique in their origins, because they're the result of high-energy particles called cosmic rays that zoom through our galaxy at close to the speed of light.

Most cosmic rays originate from outside the Solar System, and sometimes even the Milky Way, and when they collide with certain atoms, they give rise to new elements. 

Interestingly, lithium is part of the reason why Johnson decided to distribute this new periodic table in the first place. If it's giving you a serious case of deja vu, it's because there's a similar version on Wikipedia:

Jennifer Johnson

But, as Johnson explains, the Wikipedia version is unclear in some places, and just plain wrong in others.

She says the "large stars" and "small stars" in the Wikipedia version don't make much sense, because nucleosynthesis has nothing to do with the radius of the stars, so we have to assume they mean "high-mass stars" and "low-mass stars", respectively. 

"High-mass stars end their lives (at least some of the time) as core-collapse supernovae. Low-mass stars usually end their lives as white dwarfs," says Johnson.

"But sometimes, white dwarfs that are in binary systems with another star get enough mass from the companion to become unstable and explode as so-called Type-Ia supernovae. Which 'supernova' is being referred to in the Wikipedia graphic is not clear."


Head over to Johnson's blog to access a higher resolution version of the periodic table, and if you need a colour blind-friendly version, she's got you covered:

Jennifer Johnson

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• A new theory on the Creation of the Universe, disprove the Big Bang

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The above post is reprinted from materials provided by Sciencealert . Note: Materials may be edited for content and length.