You’ve Got a Little Something in Your Eye…

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A Dram of Outlander Voyager Read-Along  Chapter 60 (LISTEN HERE)

Outlander Science Club

You’ve Got a Little Something in Your Eye… (Listen to the podcast HERE!)

 

Jesus H. Roosevelt Christ,” I said.  “What was that?”

What was that, indeed!  In the search for Young Ian, Claire finds herself doctoring a young man in his twenties who is enslaved at Rose Hall. Lying quietly on a pallet in a dark corner of a kitchen pantry, he doesn’t seem to have a fever nor much distress. In fact, he appears rather well.  Until…

As though in answer to my question, the slave suddenly wrenched himself away from my hand, let out a piercing scream, and rolled up into a ball.  Rolling and unrolling himself like a yo-yo, he reached the wall and began to bang his head against it, still screaming.  Then, as suddenly as the fit had come on, it passed off, and the young man sank back onto the pallet, panting heavily and soaked with sweat.

From Voyager by Diana Gabaldon, Chapter 60

Claire indeed finds a small worm moving underneath the surface of her patient’s eye.

The Loa loa worm and Loa loa filariasis

Nope, this isn’t one of Geillis’ hexes or the product of Diana Gabaldon’s imagination. This is a real disease and Loa loa, with its predilection for swimming under the surface of its victims’ eyes is the stuff of itchy nightmares, my friends!

Loa loa, AKA African eye worm, is a parasitic worm that is passed to humans by the bite of a deerfly. Endemic only to parts of West and Central Africa, Loa loa can only be spread by the bite of the deer fly and cannot be spread person to person.  Claire’s patient at Rose Hall no doubt contracted the illness in Africa before he was enslaved and transported to the West Indies.

africa_en_map
Image: WHO

Humans are the only known hosts of the disease. No other animals are known to become infected with Loa loa.  A deerfly carrying the Loa loa larvae bites a healthy human, depositing larvae into the wound.  Once inside a human host, the larvae grow into adult worms over about 5 months and travel throughout the body.  Adult worms prefer to live between layers of connective tissue, under the skin in the subcutaneous tissue, and between the thin layers of tissue that cover muscle (fascia).  The adult worms can produce thousands of microfilariae (tiny larave) each day and spread throughout the blood stream. The deerfly can then bite an infected human, ingesting the microfilariae, which then evolve into their larval form within the fly, ready to infect the next unsuspecting human again when the deerfly bites again!

l_loa_lifecycle
From CDC – Public Domain

What happens to a person infected with the Loa loa worm?

Many patients with loiasis (infection with Loa loa worm) do not experience any symptoms.  This is more true for those people who live in the endemic regions.  Travelers to these regions are more likely to suffer symptoms.  Most commonly, those infected will develop something called “Calabar swellings.”  These localized swellings, several inches in diameter, are found on the arms and legs are caused by the body’s inflammatory response to the presence of dead worms or the metabolic products of the worms.  Itching occurs around these areas and often all over the body.

Adult worms can be seen moving under the skin, as well as just under the surface of the eye.

UtIRaAp.gif
Image courtesy of Skydmark on Imgur

Presence of the Loa loa worm in the eye causes itching, pain, and light sensitivity.  The worm generally only remains in the eye for less than one week (often just hours) and causes very little damage, since it remains just under the surface, rather than deep within the eye.

Loa loa worms can also lodge in other sites of the body, causing complications in the intestines, kidneys, heart, joints and at times, the retina of the eye.

WWCD?

What would Claire do?  Quickly requesting brandy and a small knife, Claire deftly made a small incision in the sclera of the eye with a sterilized knife. She hooked the needle under the worm and pulled it out.

Did this cure this poor man? Nope.  But it certainly provided relief from the severe eye pain.  Can you imagine the agony of that?

Treatment of Loa loa infection

Surgical removal of Loa loa worms is not curative since it is highly unlikely that a person is infected with a single adult worm. Treatment now is with medication diethylcarbamazine, or DEC, which kills both the adult worm and the thousands of microfilariae circulating in the body. Life-threatening complications including fatal encephalitis (inflammation of the brain) can occur when DEC is used in a person with very high levels of microfilariae in the body.  Therefore, in some cases, other medications are given first to decrease the microfilariae load in the body before DEC is given.  In endemic areas, treatment is reserved for those who have symptoms and also have low levels of microfilariae in the blood.

The good news?  

Loa loa is only passed from infected deerflies to humans in certain rain forests of West and Central Africa.  You cannot become infected with Loa loa from exposure to an infected person – you must be bitten by an infected deerfly to develop the infection.  So, if you haven’t travelled to that region, you are safe!  If you do find yourself traveling to West and Central Africa, there is medication that can be prescribed to prevent infection. In addition, wearing long pants and long sleeved shirts and avoiding times of day when the deerfly is most active will also help prevent infection.

Check out this video showing removal of a Loa loa worm from the eye of an infected patient by a physician in Nigeria.  ***(Not for the squeamish!)

Header Image: NIH NIAID on Flickr

 

Edited to add:  A June 15, 2017 article in Huffington Post explains more about how this disease continues to affect millions in Africa and the difficulties in treating those afflicted by it.

 

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