Friday, April 6, 2018

Will The Newly "Unearthed" Antibiotics Save Us From The Approaching Deadly Superbugs?

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"Nightmare bacteria” with unusual resistance to antibiotics of last resort were found more than 200 times in the United States last year in a first-of-a-kind hunt, according to a report by the CDC.  This hunt was undertaken to see how much of a threat these rare cases are becoming, health officials said Tuesday.  As reported in The Denver Post, the outlook isn't good.

Fortunately the problem remains relatively confined to people in hospitals and nursing homes, especially  who need IVs and other tubes, the most at risk. The reason is that these medical accessories create small apertures in the skin that can get infected. In many cases, others in close contact with these patients also harbored the superbugs (e.g. C. Diff.) even though they weren’t sick — a risk for further spread.

I am probably numbered among these given I took care of Janice when she had two severe bouts of C. Diff. in December, 2006 then January, 2007.  So evidently I may be a kind of "carrier" of the bug, i.e. harboring it but not sick from it. (I also make sure to take acidophilus regularly to create billions of healthy gut bacteria for those times I have to take an antibiotic - such as I did for gall bladder surgery in 2016 and for the 3D staging biopsy  last year.)

According to Dr. Anne Schuchat, principal deputy director of the U.S. Centers for Disease Control and Prevention, quoted in the Denver Post:

"Essentially, we found nightmare bacteria in your backyard.These verge on untreatable infections-  where the only option may be supportive care — fluids and sometimes machines to maintain life to give the patient a chance to recover".

In Janice's case, she had to be administered IV fluids - gallons of them - to replace the gallons she lost through C. Diff. diarrhea which can exceed a frequency of  20 times a day. Some physicians have even compared C. Diff. to cholera in terms of the frequency. (People become subject to infection by  C. Diff. when certain antibiotics, in Janice's case, amoxicillin, wipe out too many of the 'good' intestinal bacteria leaving an opening for the clostridium difficile to wreak havoc.)

Concern has been growing about a rise in bacteria resistant to all or most antibiotics. Last year, public health labs around the country were asked to watch for and quickly respond to cases of advanced antibiotic resistance, especially to some last-resort antibiotics called carbapenems.

In the first nine months of the year, more than 5,770 samples were tested for these “nightmare bacteria,” as CDC calls them, and one quarter were found to have genes that make them hard to treat and easy to share their resistance tricks with other types of bacteria. Of these, 221 had unusual genes that conferred resistance. The cases were scattered throughout 27 states. 

All of which elicits the question of whether there is hope for a new generation of antibioltics to combat the rising threat of antibiotic resistance and the horrific bugs that are enabled because of it.  

As serendipity would have it, the headline "New Antibiotics Unearthed" appeared in the WSJ of Feb. 13 (p. A3). wherein we learned:

"In a bag of backyard dirt, scientists have discovered a powerful new group of antibiotics they say can wipe out many infections including some microbes that arre resistant to most traditional antibiotics.":

In respect of the latter,, the lower graphic tells the sobering story of how we've very nearly come to a dead end in terms of antibiotic effectiveness.  Specifically, the initial orange marker for each antibiotic discloses the year introduced and then the black end mark shows when the antibiotic resistance was identified. Think of each black mark appended as indicating when that antibiotic's use ran out. 

According to the CDC, at least 2 million illnesses each year and 23,000 deaths can be attributed to antibiotic resistant bacteria.   Worldwide, deaths from the superbugs that evolve from the current crop are predicted to rise tenfold by 2050. So, it's a race against the clock. 

The ray of hope the WSJ reported concerns the discovery of a new class of antibiotics called malacidins, and was reported in the journal Nature Microbiology, e.g.

This discovery is described (ibid.) as "being the latest in a series of promising antibiotics found through innovative genetic sequencing techniques."  These techniques allowed researchers at Rockefeller University in New York to "screen thousands of soil bacteria that previously couldn't be grown or studied in the laboratory." 

According to Sean Brady, a biochemist at Rockefeller's Laboratory for Genetically Coded Small Molecules, a senior author of the above cited study (ibid.):

"We extract DNA directly out of soil samples. We then put it into a bug we can grow easily in the laboratory and see if it can make new molecules which are the basis of new antibiotics."

The  researchers found  the new compounds appear to interfere with the ability of infectious bacteria to build cell walls. This is a function so basic to cellular life that it seems unlikely microbes could evolve a way to resist it. (In lab tests, the bacteria were exposed to the experimental anticiotics for 21 days without developing resistance.)

The ray of hope offered by this finding may be a bit premature, however. While all the new compounds appear safe and effective there is no plan to submit them for human testing  - an essential precursor to getting them into the Pharma market.  As Dr. Brady put it: "It is the early days for these compounds."   

In the meantime, he and his Rockefeller colleagues have set up an online citizen science project called "Drugs from Dirt".   It solicits soil donations from around the world to see if the right DNA might be found to advance the search for the new generation of antibiotics.  (The sandy soil that yielded malacidin came from the Southwestern U.S.)

Who knows? Maybe the next powerful antibiotic will be developed from soil taken from your own backyard.

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