Introduction to Myiasis


Image from Insect Ecology & Veterinary Parasitology. 2002-2004. University of Bristol. 1 May 2006.9

 

Myiasis has been found to be the fourth most common travel-associated skin disease1. In Greek, myia means fly, and myiasis is defined as infestation of tissue by fly larvae2. (The word is pronounced my-eye-a-sis).

In 1840, Hope came up with the term myiasis ti distinguish the human disease caused by dipterous larvae, rather than insect larvae in general, (which was called scholechiasis)15. Myiasis is also known as “fly-strike” or fly-blown” as well as several other species specific colloquialisms4.

In 1965, German entymologist Zumpt defined myiasis as “the infestation of live vertebrate animals with dipterous larvae, which, at least for a certain period, feed on the host's dead or living tissue, liquid body substances, or ingested food8".

Myiasis might develop in a number of ways (this also affects how it presents clinically). Some flies lay their eggs in open wounds, while others invade unbroken skin or enter the nose or ears. Eggs may be deposited on lips/mouth/food and subsequently be swallowed to cause myiasis to develop in the stomach or intestine. The same is true for the genital/urinary orifices, and scrotal cases of myiasis have been reported!

Because myiasis involves so many different fly types and habits, much of its signs and symptoms will depend on what bit or infected you. However, most people who end up with myiasis are either travelers going through jungles or fly-heavy areas, or in rural regions where people are often near domestic animals.

 

Ack! Do I have to worry?

Well, maybe…but myiasis is much much worse for animals than it is for humans. Humans are actually quite often the accidental host for fly eggs.

Read onwards to see!