In this post, I will write a bit bout how germs evolve around our body as ecosystem, our mouths, its life on the surface and inside as well. I have discovered that writing this topic is quite a challenge for me, compared to the rest of the other health discussions I've written earlier. Though I will try to elaborate and explain as laymen as possible, this topic about germs will always be one of my favorite learning till today.
Preparations for the human-microbe alliance begin before birth. Midway through pregnancy, a hormonal shift directs the cells lining a woman's vagina to begin stockpilling sugary glycogen, the favorite food of the bacteria called lactobacilli. By fermenting the sugar into lactic acid, these bacteria lower the pH of the vagina to levels that discourage the growth of potentially dangerous invaders. These threats include the occasional intestinal bacterium that might stray from anus to vagina, then overgrow and spread into the uterus to cause a pregnancy-threatening infection. The acid secreting lactobacilli also provide partial protection against the sexually transmitted bacteria Neisseria gonorrhoeae and Chlamydia trachomatis, which can cause blindness in newborns infected during passage through the birth canal.
Some vaginal lactobacilli also produce hydrogen peroxide, and these extra aggressive lactobacilli are particularly effective at beating back the growth of Streptococcus agalactiae, or group B strep. Commonly found in vaginas of women who lack hydrogen peroxide producing lactobacilli, group B strep remains a leading cause of infant mortality.
Each year, we noticed hundreds and even thousands of life threatening cases of pneumonia, meningitis, and blood infections primarily in babies under one month of age. Because the natural protection of lactobacillus is far from foolproof, Western obstetricians routinely put women who tested positive for group B strep on antibiotics during labor. Ironically, previous courses of antibiotics are often to be blamed or allowing group B strep to move into the birth canal in the first place, as these drugs tend to disrupt the woman's protective lactobacilli.
Now, let's talk about germs and our mouths. How about infant's mouth? Typically, the infant mouth's first innoculation of bacteria includes a generous sampling of the lactobacilli present in the mother's canal. With the first gulp of breast milk, these lactobacilli are joined by millions of bifidobacteria, a related group of acid-producing microbes.
These microbes mysteriously appear in and around the nipples of a woman's swelling breasts during the eight month of pregnancy. There, the bifidobacteria secrete a potent combination of acids and antibiotic chemicals to repel potentially dangerous microbes. Though, the bifidobacteria themselves perish in the open air, they leave behind acids that linger for hours on the breast and in a baby's mouth.
If the newborn is fortunate, her neisseria population will include globes of Neisseria lactamica, which thrives on lactose, or milk sugar. Early colonization by this species builds strong immunity against Neisseria meningitidis, the most common cause of meningitis, a potentially deadly inflammation of the membrane covering the brain and spinal cord.
Where do all these early colonizers come from? By identifying the specific subtypes of bacteria in children's mouths, researchers have found that the vast majority trace directly to the mouths of their mothers. The maternal antibodies still circulating in a newborn's blood, which was passed during pregnancy, may further encourage the growth of microbes that they recognize as their own.
The mouth's salivary glands secrete a more constant but less intense source of bacterial food, a watery mix of protein, sugars and minerals. The mouth's first wave of aerobic bacteria consumes enough oxygen to create an underlying zone where anaerobic bacteria can thrive. These anaerobic bacteria bacteria feed on the biochemical waste products of their microbial neighbors and so help stabilize their ecosystem as it grows crowded.
Next, let's move on the discussion about germs' life on the surface. As with the mouth and nose, the colonization of the human skin begins during birth, with the lactobacilli in the mother's birth canal. These protective bacteria contribute their lactic acid and hydrogen peroxide to the bacteria-killing enzymes in the creamy vernix that covers the emerging baby.
Like the bifidobacteria of breast milk, lactobacilli don't survive long in open air. The hands and exhalations of parents and birth attendants likewise transfer bacteria to the baby's skin. Twenty four hours after birth, the suburbanization of the baby's skin has gone far, with more than a thousand bacteria per square. This rapid pace of growth continues through the second day, surpassing ten thousand per square centimeter at forty eight hours, and hitting the one hundred thousand mark by six weeks. At such densities, the skin's largely aerobic pioneers begin to deplete the limited oxygen inside hair follicles and glands, preparing them for second wave of settlers.
For most part, the skin's microflora stabilize by middle childhood. Though family and friends continuously trade microbes, fewer and fewer of these later visitors remain for long. Then, when we reach adolescence, the pimple inducing Propionibacterium acnes lives up to it name. It becomes trapped and overgrows inside overeactive oil glands. Next, the high estrogen levels of female adolescence also foster the growth of vaginal lactobacilli. A girl does not have to be sexually active to accidentally introduce a small number of these troublesome microbes into her vagina. She may do so when she wipes after a bowel movement.
Because antibiotics, especially broad spectrum antibiotics, tend to disrupt this ecological balance, they frequently trigger either yeast infections or bacteria vaginosis, which is caused by intestinal bacteria.
Now, let's talk a bit about the bacteria called E.coli. I'm not sure how many of you readers heard and know of this bacteria, but allow me to share some of my knowledge with you on this one. This bacteria, remains the best known of all the intestinal bacteria. It was the one bacterium that consistently showed up in stoll cultures and sewage-contaminated water supplies. In truth, E.coli was simply the easiest of the intestinal bacteria to grow outside the body. Anyone of you heard about the contamination of beef burgers years back in countries such as USA would surely learn one of two things about this bacteria. In this case, we are talking about commercial processed meat.
Stay tuned...
The mouth's salivary glands secrete a more constant but less intense source of bacterial food, a watery mix of protein, sugars and minerals. The mouth's first wave of aerobic bacteria consumes enough oxygen to create an underlying zone where anaerobic bacteria can thrive. These anaerobic bacteria bacteria feed on the biochemical waste products of their microbial neighbors and so help stabilize their ecosystem as it grows crowded.
Next, let's move on the discussion about germs' life on the surface. As with the mouth and nose, the colonization of the human skin begins during birth, with the lactobacilli in the mother's birth canal. These protective bacteria contribute their lactic acid and hydrogen peroxide to the bacteria-killing enzymes in the creamy vernix that covers the emerging baby.
Like the bifidobacteria of breast milk, lactobacilli don't survive long in open air. The hands and exhalations of parents and birth attendants likewise transfer bacteria to the baby's skin. Twenty four hours after birth, the suburbanization of the baby's skin has gone far, with more than a thousand bacteria per square. This rapid pace of growth continues through the second day, surpassing ten thousand per square centimeter at forty eight hours, and hitting the one hundred thousand mark by six weeks. At such densities, the skin's largely aerobic pioneers begin to deplete the limited oxygen inside hair follicles and glands, preparing them for second wave of settlers.
For most part, the skin's microflora stabilize by middle childhood. Though family and friends continuously trade microbes, fewer and fewer of these later visitors remain for long. Then, when we reach adolescence, the pimple inducing Propionibacterium acnes lives up to it name. It becomes trapped and overgrows inside overeactive oil glands. Next, the high estrogen levels of female adolescence also foster the growth of vaginal lactobacilli. A girl does not have to be sexually active to accidentally introduce a small number of these troublesome microbes into her vagina. She may do so when she wipes after a bowel movement.
Because antibiotics, especially broad spectrum antibiotics, tend to disrupt this ecological balance, they frequently trigger either yeast infections or bacteria vaginosis, which is caused by intestinal bacteria.
Now, let's talk a bit about the bacteria called E.coli. I'm not sure how many of you readers heard and know of this bacteria, but allow me to share some of my knowledge with you on this one. This bacteria, remains the best known of all the intestinal bacteria. It was the one bacterium that consistently showed up in stoll cultures and sewage-contaminated water supplies. In truth, E.coli was simply the easiest of the intestinal bacteria to grow outside the body. Anyone of you heard about the contamination of beef burgers years back in countries such as USA would surely learn one of two things about this bacteria. In this case, we are talking about commercial processed meat.
Stay tuned...
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