An short overview of parasites

[thorbiorn]

This is a journalistic presentation of some of the parasites that can bring trouble to humans. What I find useful about this article is that it brings up a problem that often overlooked in a way that is understandable. The article is from The Epoch Times

The Worm: A Sight You Will Never Forget
By W. Gifford-Jones M.D. | April 12, 2013

“Would you like ice in your drink?” To this, I normally say yes. But there are times when I say an emphatic no. I know, when traveling in the less hygienic part of the world, having an icy drink may result in the “Hong Kong Trots” or “Montezuma’s Revenge” On an unlucky day, even hepatitis B infection. Even in some North American locations, I sometimes decline ice. Why? Because I never want to see Ascaris lumbricoides in the toilet bowl. If it ever happens to you, it’s a sight you will never forget.

During my time as a family doctor, a family arrived with their young frightened son. Following a bowel movement he had noticed what he described as a “garden worm” in the toilet, and he had fished it out. Identification proved it to be Ascaris lumbricoides.

How had the boy contacted this worm? Millions of dogs, cats, and other animals are now sharing close quarters with North American families. At times this results in serious injury when an animal mangles a child. But other problems are less obvious and young children are particularly vulnerable.

Dogs and cats often defecate in playground areas. One study of 229 family dogs showed that 189 had roundworm, hookworm, tapeworm, or other parasites. Children who swallow a parasite egg can later pass a worm as long as one foot. Can this also happen to adults? You bet, and it can make their hair stand on end.

Roundworms are very fertile, laying up to 100,000 eggs in a single day. If one of these eggs is accidentally ingested by a dog, the worm hatches and makes its way to the intestines, an ideal feeding ground to be passed on later to humans.

Ascaris lumbricoides can also trigger human intestinal symptoms. A 65-year-old man was admitted to emergency complaining of vomiting and severe pain suggestive of intestinal obstruction. X-rays confirmed the diagnosis. But just before surgery the man suddenly expelled a huge lump of worms. His symptoms quickly subsided.

I’m sure many readers are thinking this problem is rare. After all, we don’t live in the tropics. But according to the U.S. Center for Disease Control, a quarter of the world’s population suffers from Ascaris lumbricoides. And 4 million North Americans harbor this worm.

During a visit to the London School of Hygiene and Tropical Medicine, I discovered that worms can cause more than intestinal obstruction. One of the school’s doctors had a hair-raising experience. He was performing a routine eye examination when suddenly he observed an exotic worm from West Africa crossing the patient’s eyeball. On rare occasions Ascaris lumbricoides can also infect the eye.

So can you prevent having your hair stand on end? I love dogs, but I’ve often watched friends run their hands down their beloved Fido’s tail, then reach for the ice cubes! Worms such as Ascaris are picked up from fecal contamination. And I’ve never seen Fido washing his tail after defecating. This is when I say “no” to ice cubes in my drink. But Fido isn’t the only animal that can cause problems.

Pregnant women must be careful of cats as their feces can cause toxoplasmosis. During pregnancy this parasite can be transmitted to the fetus resulting in serious birth defects. So, when pregnant, let someone else clean out the litter box.

Remember that pet squirrels have a tendency to bite. Turtles can pass along salmonella infection to the entire family causing severe diarrhea. So it’s not prudent to dump turtle water into the kitchen sink. Parrots, parakeets, and pigeons are noted for causing a lung infection called psittacosis. Monkeys are dangerous pets. If you are crazy enough to keep one in the house, you may end up suffering from hepatitis, measles, encephalitis, or amoebic dysentery. Or losing friends!

Suppose your child can’t live without owning a hamster. These animals can cause lymphocytic choriomeningitis. So make sure you buy it from a colony that has been screened for this virus.

It’s been said that cleanliness is next to godliness, and who can argue with this advice? But it can also save you from having your hair stand on end.

Dr. Gifford-Jones is a medical journalist with a private medical practice in Toronto. His website is DocGiff.com. He may be contacted at Info@docgiff.com.

 

[Voyageur]

This is a journalistic presentation of some of the parasites that can bring trouble to humans. What I find useful about this article is that it brings up a problem that often overlooked in a way that is understandable. The article is from The Epoch Times

The Worm: A Sight You Will Never Forget
By W. Gifford-Jones M.D. | April 12, 2013

Interesting you brought this up as i was looking into parasites a few nights ago in relation to the Iron thread not animals:

_http://www.medicalnewstoday.com/releases/226732.php

Insights On Humans, Parasites And Iron Deficiency From C. elegans Study:

Lee Tune
University of Maryland


Using a tiny bloodless worm, University of Maryland Associate Professor Iqbal Hamza and his team have discovered a large piece in the puzzle of how humans, and other organisms safely move iron around in the body. The findings, published in the journal Cell, could lead to new methods for treating age-old scourges - parasitic worm infections, which affect more than a quarter of the world's population, and iron deficiency, the world's number one nutritional disorder.

Using C. elegans, a common microscopic worm that lives in dirt, Hamza and his team have identified a protein, called HRG-3 that transports heme from the mother's intestine to her developing embryos. This finding builds on a breakthrough Hamza's team made three years ago, when he and colleagues discovered HRG-1, a protein common to humans, which transports heme from the environment into the intestine of C. elegans.

Iron Life

Iron is an absolute requirement for humans and most other forms of life, but, because it is a free radical 'instigator,' it can also be toxic. To protect themselves, organisms surround iron with protein escorts to allow it to be safely moved within the body. The most important class of iron-containing compound is heme in hemoglobin, the most familiar iron-binding protein which carries oxygen and makes blood red.

"We've known the structure of hemoglobin for a really long time," said Hamza, "but we haven't been able to figure out how the heme gets into the globin, or exactly how humans and other living organisms move heme, which like iron is toxic, around and between cells."

Hamza first started trying to uncover the secrets of heme transport in 2003. He and his team were studying the molecules and mechanisms involved in heme absorption in the intestine of C. elegans when, in 2008, they discovered that the protein HRG-1 escorts heme into the worm's gut, the first step of the intercellular journey.

"Now, in this current study we've looked at the next step in the transport process, which is how the worm moves heme from the intestine to other parts of its body" he said.

Hamza explained that for this next step they chose to study transport of heme between the mother's intestine and developing embryos because studies in mammals had implied the existence of a pathway for ferrying and depositing mother's heme into her embryos, but no such route had been identified.

In C. elegans, it was easier to manipulate experimental conditions to clearly see the life and growth impacting effects of the presence or absence of heme while simultaneously looking at two separate organisms - the mother and her embryos all residing within a fully transparent living animal.

"What we've found in our current study is that this protein, which we named HRG-3, takes heme from the worm intestine to the embryos," he said. "We believe this protein is also involved in transport of heme from the worm intestine to the other parts of a worms' body such as its brain, skin and muscle."