The Kennewick courier-reporter. [volume] (Kennewick, Wash.) 1939-1949, 1940-03-07
Illumination
Against Sleeping
Sickness is Urged
Vaccination Proving Eff
fective in Preventing
Horse Disease

,-ompts consideration of Sleeping
sickness among olir horses. So that
70 may be able to analyze our po-
.ition. let us review the situation
briefly. My first experience with this
endemic, writes Geo. Sellick, who
has been treating the disease in the
-o,lev dates pack to 1887 when
.ho,,t dozen sporadic cases came
.rder INV observation. No attempt
.,oe made to treat these cases since
a. that time no treatment was
Known. What happened in 1888 re-
n,,ires no repetition. It is still too
vivid in the minds of everyone. The
disease came rather early in 1899.
First case appeared late in March.
There was lapse after this case
the second appearing late in May.
This second case Immediately
simulated active interest in vaccin-
alton as prophylactic measure in
preventing the disease. From May
TO mid-September about forty cases
came to my attention. OF these %
we're given treatment by means of
intrayenous injections. OF those so
treated is recovered, six died. Of
the eighteen not treated twelve died,
nix recovered without treatment.
Thus last year, using observed
cases only, the mortality without
treatment was 66 percent; % per-
cent where treatment was attempt
ed and an overall mortality of As
percent. This would seem to indicate
that p roper treatment used early in
the disease IS decidedly worth while.
It seems evident that these cpl
denies have certain characteristics.
The first year there are usually
limited number of cases, a rapidly
increasing number the second year
with high mortality, followed by
slowly descending gradient during
the following years. Our epidemic
shows this tendency tho our vaccin-
alton. campaign has introduced SER
ious Obstacles to securing a charact-
erstic graf. During the period from
May TO late September almost two
thousand horses were vaccinated be-
tween Wallula and Cold Greek. Many
Of these were vaccinated after the
appearance Of the disease which
means that many of them had been
exposed to possible infection.
In mid-september the disease
stopped abruptly with only four
cases IN the following six weeks and
~ OF these unvaccinated horses. OF
those which were vaccinated only
two contracted the disease within
iour days after the first injection.
As the disease has an incubative
period Of from seven to fourteen
DAYS 1t Is easy to see that these two
noeSes had contracted the disease
before the initial injection. In no
ease wnere q horse had received the
mitaal injection for seven days did
sne disease appear, though complete |
immunity does not develop in less
eaan tWenty-one days. This would !
seem to make a very good case for
.:mmmization, demonstrating that it |
Is as near perfection as any tyne of |
vaccination in use today.
But ! am convinced that 1t will
sun De menace to unprotected
horses We have no additional data
. !, to the length of the immun-
NY produced. In 1898 in October
some 80 horses were vaccinated. OF
sns number two head developed the
usease In mild form, one at ten
= after vaccination, the 9TH
= AZ eleven months. believe that
sls proper time to revaccinate is
. sa..n one year of previous vaccin-
ssaon. Unprotected stock should be
"ea.eo as soon as possible after
. salcn 10. Earlier will do no harm.
.uougn the early vaccination NAV
an esuls IN lowered immunity in late
, ra wnen the disease can be very
sesaient. Horses which have re-
.Oseteo from the disease are prob