Communicable diseases and wounds without modern day treatments of vaccines and antibiotics were deadly for our ancestors. According to the World Health Organization (WHO) 70% of worldwide deaths are a result of diseases that cannot be passed from one person to another.
These noncommunicable diseases are produced from a combination of lifestyle factors, environment and genetics versus transmission by bacteria, virus or fungi. However, in recent years, scientists are developing a hypothesis suggested by studies that a collection of microbes found in and on the human body, known as microbiome can influence your health. This includes the transmission of what are considered noncommunicable diseases such as cancer, diabetes, inflammatory bowel, cardiovascular disease and others.
Certain microbes or “bugs” help in directing the function of certain physiological systems. These include digestion, immune defense and metabolism. Certain diseases have been linked to bacterial imbalance in the body.
For instance, people with diabetes, inflammatory bowel disease and cardiovascular disease tend to host a different collection of bacteria in their guts than those without the diseases, according to a report published Jan. 16 in the journal Science. The paper suggests that healthy people could potentially "catch" aspects of these ailments through exposure to these mixed-up microbes.
B. Brett Finlay a microbiologist at The University of British Columbia in Vancouver stated, "It is a radical thought to think that [noncommunicable diseases] might actually be communicable, and [this hypothesis] gives us a whole new way of thinking about these diseases.”
Finlay and his colleagues developed a hypothesis based on a 2019 study carried out in Fiji. They also considered the finding of other studies to arrive at the hypothesis.
The study took stool samples and saliva from 290 persons who lived in close proximity to one another to determine what bacteria existed in their mouth and gut. The results found a distinct pattern of bacterial transmission between members of the same community, especially among those living in the same household.
Those with the closest similarity were found between mothers and their offspring and between spouses. “The team could even predict which study participants were paired up as a couple based on their microbiomes alone.”
The Fiji study found that microbiome can be passed between persons, and this could possibly also drive the transmission of what are considered “noncommunicable diseases”.
"Spouses of people with type 2 diabetes, for example, stand a higher chance of developing the disease themselves within a year of their partner's diagnosis", Finlay noted. In an animal model of the disease, germ-free mice developed diabetic symptoms after receiving a bacteria-laden fecal transplant from a diseased mouse. Similar trends have been uncovered in inflammatory bowel disease, both in human spouses and animal models.
Even cardiovascular disease may be linked to the presence of particular bacteria in the gut, Finlay noted. Studies show that bacteria linked to cardiovascular disease if transferred from a human into a mouse, but it's unknown whether the same might occur between people.
Other studies suggest that there are other “noncommunicable diseases” influenced by bacteria can travel between people. These microbes alter immune function, which is relevant to cancer patients whose immune systems fail to attack tumors in the body.
Finlay said, "Our lab has shown that early-life microbes impact hugely on asthma ... and we have some very exciting preliminary data with Parkinson’s.”
Obesity, a major risk factor for noncommunicable diseases, also involves potentially transmittable microbes. Lean mice become obese when they receive a fecal transplant from already-obese mice, while humans with obese friends or siblings stand a higher chance of being obese than those who don't have obese friends or siblings. Living in a country with a high obesity rate also raises a person's risk of being obese. But all of these studies raise a similar question: How can scientists tell which aspects of a disease might be linked to troublesome microbes, as opposed to diet, exercise, genes or environmental factors?
In the process in which science determine how these noncommunicable diseases hop from an unhealthy person to a healthy one, some companies are starting to develop so-called second generation probiotics designed to rebalance the gut microbiome.
If Finlay's hypothesis garners support over time, it could lead to an entirely new understanding of noncommunicable disease.
"It has significant public health policy implications," Finlay said, "and further suggests that looking after your own microbes will not only benefit you but also people close to you."
Source - LiveScience
Stranger Than Fiction Stories by Marlene Pardo Pellicer