Creative Nonfiction – July 2019

(Brent) #1

CREATIVE NONFICTION 47


He decided to set me up with houseflies.
Houseflies, I knew, were not only uninteresting
but were also nothing more than adult mag-
gots. I kept my mouth shut. It was the start of
my senior year, and I had thirty dollars to my
name. Plus, I was an English major and lucky to
be in the lab in the first place. An entomology
minor, afraid of the two years of chemistry,
physics, and other weed-out classes the major
then required, I’d impressed Drion with my
writing in his “Principles of Entomology” class,
but I knew he could have taken on any number
of science students in my stead.
So, when he dispatched me down the road to
the U.S. Department of Agriculture’s Center for
Medical, Agricultural, and Veterinary Entomol-
ogy to learn how to rear flies from their fly guy,
I hustled.
The fly guy at the USDA was a grad student
from Argentina with a backward baseball cap
and a belly I found attractive. He gave me a tour
of the fly-rearing facility, opening one of the
large walk-in incubators that housed the many
colonies.
“You want to keep it humid,” he instructed.
“And simulate the natural cycle: twelve hours of
light, twelve hours of darkness.”
The larvae were kept in deep trays of com-
post material stacked on the wheeled racks
typically found in cafeterias. He pulled one out
and turned the dirt over with a bare hand to
expose a mass of maggots. “Here are the little
guys. You don’t even need to cover the trays—
they can’t climb out.”
I looked down at thousands of wriggling
bodies: blind, limbless, and with those two
tiny hooks at the end of what would be, in
another animal, the head. They were the
elephant seals of the insect world. Unforgiv-
ably ugly.
The f ly guy gave me a box of pupae to start.
The pupae—the life stage between larva and
adult—were much easier on the eyes; the
repulsive forms of the maggots were hidden
inside clean, brown shells with neatly spaced
striations. When I shook the container, it made
a heavy sound, like a box of beads. I biked back
to the lab, clutching the colony against my
handlebars.


in the early nineties, Drion was part of a
research group that discovered a naturally oc-
curring disease in populations of wild houseflies
in the dairies of north Florida. Known as Musca
domestica salivary gland hypertrophy virus, or
MdSGHV, the virus causes severe hyperplasia of
a fly’s salivary glands, meaning the glands swell
enormously. Sometimes they grow so large they
coil and contort over themselves to fill most of
the fly’s body cavity. In the worst cases of infec-
tion, the virus can inhibit feeding altogether,
starving the fly to death. However, this is quite
rare; the virus has developed the ability to rep-
licate exponentially in the glands of an infected
fly without killing its host. Keeping a fly alive is
extraordinarily beneficial to the virus, particu-
larly as its main means of transmission is per os,
that is, by mouth. MdSGHV-carrying flies can
contaminate whatever surface they feed on, and
only one droplet of saliva is needed to trigger
the complete infection of another fly.
After publishing a description of the virus,
Drion’s lab had moved on to other diseases, not
seeing any profit in pursuing MdSGHV further.
But with my work-study labor at his disposal,
Drion decided to return to his study of the
virus, focusing on other possible means of trans-
mission. Specifically, he wanted me to conduct
an experiment that would either confirm or rule
out the possibility that it could be passed sexu-
ally and/or vertically—from infected parent to
progeny.
While houseflies don’t directly vector diseases
through a bite, as many other insects do, they
can mechanically transmit pathogens that
cause illnesses such as salmonella poisoning and
dysentery. And they can be a nuisance, espe-
cially in dairies, where fly populations can reach
plague-like proportions. Since MdSGHV is a
disease that can’t be transmitted to mammals or
humans, Drion was interested in the possibil-
ity of using the disease as a biological control
of flies, a novel concept as most other controls
target the immature life stages of the fly, not the
adults.

salivary glands are crucial to a fly because
of their role in digestion. The housefly cannot
chew. If you look a housefly in the face, under
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