Alexandria gazette. [volume] (Alexandria, D.C.) 1834-1974, 1884-06-26
DANGERS FROM FLIES.

In note communicated to the Gaz=etta
degli Ospiltali for August, 1883, and repub-
lished in the current number of the Archives
Naliennes de Biologie, DR.. B. Grassi calls at
tention to the fact that flies are winged
agents in the diffusion of infectious maadies,
epidemics, and even parasitic diseases.
During the summer season, when flies oc-
cur in swarms, it seems impossible to pre-
vent them from settling on any and every
object. In these countries, though some
times troublesome, they are scarcely ever
so numerous as in the warmer climates of
the continent, and even in these latter they
are not often to be found such plaques as
they are in Egypt; but in all these coun-
tries alike they may be seen to alight on all
may be the cxpectorations of phthisical
or the ejecta of typhoid patient that have
last attracted these inquiring diptera; but,
irrespective of the material they may
have been investigating, their next visit
may be to the moist lips or eyes of
human being. Their feet, their
mouth and the pectoral portion of their
bodies will have all come in con-
tact with the iniective mass, and will all in
turn be more or less cleansed Of it by the
moisture of tho freshly visited mucous men,
branes But this danger has already been
known and recognized and it seems scarce
ly doubtful that in Egypt ophthalmia is
constantly carried to the eyes Of the infant
natives by such winged visitors. DR.. Grass
calls our attention to even greater danger,
and this from the ejecta Of the flies them
selves. Every housekeeper knows how the
bright surface of a mirror or the gilt mould
ing Of a picture frame can be covered over
with the little tlecks left by these nies-no
English words occur to us to translate there
with the phrase "lcs mcfaHc dcs mouchcs." !"
The following experiences of DR.: Grassi
relate to these: AT Rovellasca, between
his laboratory, which is on a first floor, and
his kitchen, which is Oh the ground floor,
there lies a court yard, with a distance be-
tween the windows Of the two rooms of
about ten metres On plate on the table
of his laboratory he placed large number
of tho eggs Of human parasite (Tricho-
cephalus). After few hours he found, on
some white sheets of paper hanging in the
kitchen, the well known spots produced
by the excreta Of the flies, and on a
microscopical examination of these spots,
several eggs Of the parasite were
found in them Some flies coming into the
kitchen were now caught and their intesti-
nal tract was found quite filed with an
enormous mass of focal matter, in which
the presence of eggs Of Trchocephali were
detected. AS it was practically impossible
to keep all alimentary substances from con-
tact with these flies, it follows that the
chances Of Dr. Grassi and his family being
infected with Trichocephai were very great
AS a matter Of fact, the experiment was
tried with non -segmented eggs of this worm.
Another experiment was in the same direc-
ton. DR.. Grassi took the ripe segments of
a Tmaia solium (which had been in spilits Of
wine) and broke them up in water SO that
great number Of the tapeworm eggs re-
NAMED suspended in the fluid. The flies
came to the mixture, attracted by the sugar.
and in about half an hour the ova OF the
tapeworms were to be found in their lntes-
tines and in the spots. Had these eggs
been in o recent and living state, they would
doubtless have been just as easily trans
ported. To those who care to try these eX-
periments, it is suggested that lycopod
powder mixed with sugar and water is u
good material, as the lycopod spores are
easily detected.-Naturc.