Wednesday, February 11, 2015

Uncertain Health in an Insecure World – 23

“The Buggy-man Cometh”

A recent study about the microbes that populate the subterranean world that is the New York City Subway showed that 5.5 million daily travelers are surrounded by DNA fragments of 637 diverse bacteria, viruses and fungi, including pseudomonas, anthrax, enterococcus and (yes!) bubonic plague.

So the ‘buggers’ are inside the gates, in sci-fi Ender’s Game speak.

Surprisingly, 48% of the microbes discovered had DNA that was unmatched to any known organism. Some 12% of the bacteria could potentially cause human diseases, and 27% of samples were from antibiotic-resistant bacteria. Despite common fears of catching viral infections in public places, only 0.032% of New York Subway DNA was viral. One subway station flooded in October 2012 by Hurricane Sandy had a microbiota characteristic of the cold water Atlantic Ocean.

In a move that would please the pro-open access Bill & Melinda Gates Foundation (see Post #16), the authors published their research on the Subway Microbiome in the on-line journal Cell Systems.

1958 Nobel Prize for Medicine winner Joshua Lederberg is credited with coining the term microbiome, the “microorganisms that share our body space…” In fact, microbial organisms (mostly living in our gut) outnumber human body cells 10-to-1! Collectively, an entire human microbiome weighs approximately 200 grams, or 7 ounces. Americans are collectively colonized by 10,000 microbial species with 8 million unique genes.

Why is it that we’re suddenly so keen to understand the human microbiome?

The art of the possible is involved.

In 2001, the Human Genome Project estimated that the cost to sequence a single human genome was US$100 million. The most recent 2013 cost-estimate dropped to just US$5,671. High technology has enabled the exploding field of “metagenomics”, spawning the Human Microbiome Project (HMP). Until recently funded by the U.S. National Institutes of Health (NIH) Common Fund, the HMP comprised only 2% of the total NIH budget in 2006. 

Despite >15 years squarely on the global scientific map, at the 2013 NIH Human Microbiome Science meeting attended by leaders in the field, co-host Dr. Owen White (also the HMP lead on large data management & data sharing) chastised his colleagues for repeatedly referring to the “gaps” in their HMP-enabling technologies. Said Owen, “I came here to be schooled, no kidding, on the specific obstacles to really getting science done”. He left the meeting wanting, it appears. 

HMP now has international partners in Canada, Korea, Australia and Europe.

Their research shows that important immunogenic micro-organisms are passed from mother to child during vaginal births. This is important health protection is lost in a Cesarian section, possibly predisposing C-section babies to emerging global chronic illnesses like asthma, diabetes, celiac disease and obesity (see post #10).

Agribusinesses that fatten cattle and other livestock with nontherapeutic drugs (see post #19) are also shifting the gut microbiomes of those eating these antibiotic-modified foods. Underfed people in rural Malawi, Burkina Faso and the Amazon have greater gut microbial diversity than urban Europeans, but still die younger and suffer more diarrheal intestinal illnesses.

Start-up spawn of the same Big Pharma companies that brought us multi-drug antibiotic resistant bugs like methicillin-resistant staph aureus (MRSA) see their future profitability tied to microbiome-modulating drugs for difficult-to-treat inflammatory bowel diseases (i.e., ulcerative colitis), obesity (i.e., metabolic syndrome), etc.

HMP scientists continue to warn of the complexity of the big data generated by their microbiome research… of analytic data “gaps” that confound their observations (see post #18).But for most of us, the simplest things, like eating bifidus regularis-laden yogurt, remains the only real-life microbiome building intervention available.

An average 165 pound human has approximately 350 times more cell-based than microbiome DNA. It's good that enabling metagenomics technology can now explore the significance of these bugs to human health.

That said, the developed world's scientific and Pharma R&D's laser-like attention to this potential druggable target feels like a public research funding and for-profit boondoggle. This is especially true when the global one trillion dollar drug bill, 50% of which is expended in the U.S., will likely never benefit the less developed, under-served people of the world.

We in the Square are all for the advancement of science, and see the benefits of bio-medical research on global human health. But for the moment... please pass the yogurt.

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