You can read all of Teresa's posts on The Microbiome and our other series reports in our EXCLUSIVES category.
- The Microbiome: Could It Be The Epicenter Of Autism?
- Autism: Does Mercury Modulate The Microbiome?
- The Microbiome In Regressive Autism
- The Microbiome: Could It Be The Epicenter Of Autism?
- The Human Microbiome: Evolution of Vaccine Exposure
- Autism And The Microbiome: Knock-Knock-Knock Penny And The Increasing Observations Of OCD
- Autism and the Microbiome:1st International Symposium and an Odyssey
By Teresa Conrick
I continue to read and piece together facts about the microbiome because it seems very much involved in my daughter’s regression into the abyss of autism. Megan is twenty-one and has both an autism and autoimmune diagnosis. She regressed in her second year of life. Antibiotics, called both good and evil if you read on the internet these days, are being named a connected culprit in the damage being seen in the microbiome:
Scientist Martin Blaser argues that we are suffering from new wave of 'modern plagues' such as obesity and asthma because we have destroyed the naturally occurring bacteria in our bodies….Over the past 150 years, most countries have been getting healthier. Chalk it up to improved sanitation, rat control, clean drinking water, pasteurised milk, childhood vaccinations, modern medical procedures and, of course, 70 years of antibiotics….Yet recently, just within the past few decades, amid all of these medical advances, something has gone terribly wrong. In many ways, we appear to be getting sicker. You can see the headlines every day. We are suffering from an array of what I call "modern plagues": obesity, childhood diabetes, asthma, hay fever, food allergies, oesophageal reflux and cancer, coeliac disease, Crohn's disease, ulcerative colitis, autism, eczema. In all likelihood, you or someone in your family or someone you know is afflicted. Unlike most lethal plagues of the past that struck relatively fast and hard, these are chronic conditions that diminish and degrade their victims' quality of life for decades…These disorders suggest that our children are experiencing levels of immune dysfunction never seen before. And then there's autism – a much discussed and debated modern plague that is a focus of my laboratory…..
….we need to look closely at the micro-organisms that make a living in and on our bodies – massive assemblages of competing and co-operating microbes known collectively as the microbiome….The microbes that constitute your microbiome are generally acquired early in life; surprisingly, by the age of three, the populations within resemble those of adults. Together, they play a critical role in your immunity and ability to combat disease. In short, your microbiome keeps you healthy….And parts of it are disappearing.
The reasons are all around us, including overuse of antibiotics in humans and animals, caesarean sections, and the widespread use of sanitisers and antiseptics, to name just a few…..In the presence of antibiotics, the resistant organisms are the ones more fit; it is the pressure of intensive antibiotic use that is increasing the presence of these resistant organisms.…….
If that is true, should we not worry about MERCURY as well?
The following scientific studies tell the story and a history that should be included as we look at the microbiome:
“Is exposure to mercury a driving force for the carriage of antibiotic resistance genes?”
…we analysed mercury resistance in collections of strains from various populations with different levels of mercury exposure and various levels of antibiotic resistance. The first population lived in France and had no known mercury exposure. The second lived in French Guyana and included a group of Wayampi Amerindians with a known high exposure to mercury. Carriage rates of mercury resistance were assessed by measuring the MIC and by detecting the merA gene. Mercury-resistant E. coli was found significantly more frequently in the populations that had the highest carriage rates of antibiotic-resistant E. coli and in parallel antibiotic resistance was higher in the population living in an environment with a high exposure to mercury, suggesting a possible co-selection. Exposure to mercury might be a specific driving force for the acquisition and maintenance of mobile antibiotic resistance gene carriage in the absence of antibiotic selective pressure….This confirmed the well established link between mercury and antibiotic resistance (Edlund et al., 1996; Liebert et al., 1997; Pike et al., 2002, 2003; Ready et al., 2003, 2007; Summers et al., 1993; Wireman et al., 1997).
Some of bacteria have developed special resistance mechanisms against mercury, in addition to resistant to different antibiotics. These bacteria usually acquire Hg and antibiotic resistance genes via horizontal gene transfer in their habitat…
They reported that there is a direct relationship between increased use of herbicides and spreading resistant to mercury in bacterial communities residing in agricultural soils (9). Enhancement of mercury contamination increases antibiotic resistant strains. This is a serious environmental and public health concern in such regions (10-12). Moreover, using mercury-containing products such as disinfectants and amalgam may cause spreading of multiple antibiotic resistance strains in hospitals and human intestine (3, 13)..
Mercury and antibiotic resistance has long been a subject of interest in microbiology that a vast of literature consisting of studies that looked at its genetics and molecular mechanisms. The aim of this study was to isolate and identify Mercury resistant and antibiotic resistant bacteria and determine the Hg-resistant isolates were also antibiotic resistant….
In two studies, a large fraction of healthy, non-antibiotic-treated infants in the first 3 months of life harbored resistant and multiple resistant bacterial strains [59,60], perhaps through maternal transmission . Although it has yet to be evaluated epidemiologically, the growing presence of resistant microbes may be due in part to more widespread contaminant exposures from foods and the environment. For instance, several studies demonstrated that individuals exposed to mercury were more likely to possess resistance to multiple antibiotics, suggesting a coselection mechanism …. These multiresistant pathogens heighten risk of adverse outcomes, especially in young children. Once antibiotic resistance genes are selected for, they may persist within the microbiota for years .
Because mercurial compounds were commonly used as disinfectants in medical settings they selected for Hg resistant bacteria (Porter et al., 1982); in light of such observations, Hg-containing disinfectants were largely replaced by quaternary ammonium disinfectants during the 1980's. By that time, advances in the study of bacterial gene transfer had revealed that plasmids, which are small circles of DNA capable of moving themselves from one cell to another, could carry multiple genes for resistance to several different antibiotics. Plasmids were then revealed to be the major agents mediating the newly recognized spread of antibiotic multiresistance. Many of the first studied plasmids also carried resistance to mercury and organomercury (e.g. merthiolate) compounds genetically linked to the antibiotic resistance loci on these transferrable bacterial plasmids. Consequently, exposure of bacteria to any agent for which their resident plasmid provided resistance would indirectly select (co-select) for all of the other genetically linked resistance loci on that plasmid (Fig. 2).
Plasmid sharing is one way bacteria develop resistance not only to antibiotics but to any agent that threatens their survival, including metals. In situations where intestinal bacteria are continuously exposed to a metal such as mercury, those bacteria with the genetic machinery that enables them to tolerate the metal are more likely to survive and reproduce. Anne Summers, a microbiologist at the University of Georgia, explains, "In the high-impact environments there are more complex plasmids, but the underlying machinery for generating that complexity has been enabling bacterial evolution for eons." She says humans have generated unprecedented environments with high concentrations of antibiotics and metals, especially mercury, inside our bodies.
Summers says bacterial exposure to metals such as mercury can contribute to antimicrobial resistance because many transferrable plasmids carry genes for multiple types resistance. In other words, in the process of developing metal resistance, a bacterium may also become resistant to an antibiotic it hasn't even encountered. This is important because the result of our collective microbiomes' gene transfers may not always be as good for us as they are for our microbiomes, says Les Dethlefsen, a staff scientist at Stanford University. As Silbergeld puts it: "We may exist at the pleasure of the microbes."
Resistance to mercurials (Hg') is a common plasmid-determined property of both gram-positive and gram-negative bacteria (64, 331, 369,417, 418). This may have been caused by the use (until recently) of mercurials such as phenylmercury and thimerosal as hospital disinfectants (148) or by industrial and urban pollution. A decreasing incidence of mercurial resistance in hospital strains has coincided with the discontinuation of mercurial disinfectant usage (300).
Sadly in that science, we can see how mercury could affect the bacteria of humans, the microbiome, and not in a good way. On August 29, 1931, Vivian Ann Murdock was born. She was to be the first child born of the Kanner 11, those first ever children diagnosed, autistic. Her arrival was years before antibiotics were available, like the rest of those ill-fated eleven, but the timing and her place of birth, Baltimore, put her in the bull’s eye of Thimerosal. The connection to mercury in those children and in those families is just too coincidental and tragic.
Some more research to paint that picture:
MERCURY IN MEDICINE REPORT
HON. DAN BURTON OF INDIANA
IN THE HOUSE OF REPRESENTATIVES
In October 1929, Eli Lilly and Company registered thimerosal under the trade name Merthiolate. Merthiolate was used to kill bacteria and prevent contamination in antiseptic ointments, creams, jellies, and sprays used by consumers and in hospitals. Thimerosal was also used in nasal sprays, eye drops, contact lens solutions, immunoglobulins, and most importantly here—vaccines. Thimerosal was patented the same year that Alexander Fleming discovered penicillin. But because it took more than a decade for penicillin to be fully developed, and large-scale production to begin, thimerosal was widely used in the interim. To the medical profession, who were without antibiotics during the 1930’s and 1940’s, thimerosal (marketed as Merthiolate) and other antiseptic products were gladly received.......Thimerosal became the most widely used preservative in vaccines and other medical products. Its use in antiseptic products to prevent infections was common. By the time that the FDA conducted its review of mercury in 1999, more than 50 licensed vaccines contained thimerosal.
…alkyl mercurial compounds such as ethyl mercury have been characterized as readily absorbable when put in contact with the skin or as able to readily cross cell membranes [35, 37].
Degraded solutions of thimerosal possess greater antibacterial activity than freshly prepared solutions . Ethyl mercury, the specific species of mercurial which blocks bacterial growth, becomes more plentiful with time and is not lost in solution . Thimerosal added to vials of hepatitis B vaccine undergoes rapid, partial (29-44%) degradation to ethyl mercury and then is stable for at least 3 years . The degradation occurs without loss of antimicrobial activity.
…..It has been suggested that the widespread use of thimerosal in vaccines and various other products for medical use may account for the fact that thimerosal usually produces the highest frequency of positive skin reactions in the general population in dermal patch tests .
And this quote may be the most important of all:
….early-life toxicant exposure could shift the microbial balance, potentially affecting both immune and microbiome development…
If mercury, especially Man-made mercurials, can affect bacteria like antibiotics, it is important as we look to the microbiome as both the problem but also the solution.
Teresa Conrick is Contributing Editor to Age of Autism.