In what is perhaps a play on words, the botfly species
Dermatobia hominis is called the Human Botfly. In spite
of its name, the insect is known to infest many other
mammals, including dogs, cattle, rabbits, and monkeys.
When it is time to reproduce, the female botfly captures a
female mosquito and, without harming it, lays her botfly
eggs on it in a sticky substance she secretes. (It sounds
incredible, but this actually happens.) The mosquito is
released from the fly’s grip, and if it eventually lands on a
human, a botfly egg hatches as the mosquito is feeding—
so you get a mosquito bite and a botfly. A tiny larval
botfly burrows into the skin of the human host. This is
a condition called myiasis, a medical term that means
“you have a maggot growing in you.” The subcutaneously
growing maggot is covered with tiny spines and it has
a propensity to move, creating intense irritation on the
site. You soon become aware that something is amiss,
and you will likely notice a raised and perhaps reddened
lesion on your skin, signaling the home of the botfly
larva. Local itching and occasional sharp pain continues,
as the spine- infested larva moves and grows within
you. If left untreated, the maggot will continue to grow,
passing through several developmental stages called
instars. This process requires anywhere from five to 12
weeks, a long time to play host to a maggot. But if the
maggot matures, it emerges, drops from the host, and
pupates in the soil. Once that happens an adult human
botfly emerges and, using its superb olfactory sense, flies
off to find another botfly with which to mate.
I have personally experienced two bouts with human
botflies and know many people who have had multiple
bouts with them. So what to do? The maggots need air
and breathe through two tubelike spiracles, openings
at the tip of their abdomen. It is possible to deprive the
maggot of air, thus killing it. Even if not killed it will come
near the surface of the lesion where it can be removed
with forceps or be gently and carefully squeezed out. This
solution worked for me. Another solution is, believe it or
not, to bribe it. Some folks claim to have taped a piece
of bacon or other meat over the lesion area, and the
maggot subsequently exited the human and entered the
bacon. I cannot vouch for the efficacy or veracity of this
approach. The most conventional approach is to have
the maggot surgically removed. Or you could simply
ignore the creature within you, let nature take its course,
and watch as the remarkable insect eventually takes its
leave of you. There you have it.
Sand Flies and Leishmaniasis
Sand flies are tiny flies in the family Ceratopogonidae
that are often abundant along sandy rivers and beaches
in the tropics. They can be active throughout the day
but are a most active at dawn, dusk, and at night. They
are sometimes called no- see- ums, but there are biting
midges that are also called no- see- ums. The two should
not be confused. Sand fly bites, like mosquito bites,
result in reddened itchy spots that are really annoying.
But that is not what should concern you. Sand flies
are vectors for various species of a protozoan that can
produce a condition known as leishmaniasis. Weeks
to months after the protozoan is introduced into the
bloodstream via the bite of a sand fly, you may notice
skin lesions around the face or arms and legs that
appear without explanation. These lesions could be
sensitive to touch, even outright painful. The lesions,
caused by the leishmania protozoans take months to
resolve and can reappear in the future. Worse yet, the
condition may become severe, affecting the spleen
and liver. Leishmaniasis is a serious medical condition
that has the potential to be fatal and thus requires
monitoring and treatment.Bees and Wasps
Bees and wasps abound in the Neotropics, and many are
formidable stingers that become aggressive if disturbed.
Wasp and bee nests are readily visible in trees (plate A-
1). Recall that oropendolas and other bird species often
nest in proximity to a colony of wasps or bees, gainingPlate A- 1. Do not disturb. A colonial wasp nest in understory
vegetation rather near the trail. Best to leave these alone.
Photo by John Kricher.390 appendix appendix