The Baltimore County union. [volume] (Towsontown, Md.) 1865-1909, 1902-05-24
HEAT AND DISEASE.

the cause or some or the most fatal
infectious diseases that aff1ict the hu-
man race. In fact, the greatest dis
infectant in nature is light, or, to be
more exact, the radiations of the sun,
including heat rays, light rays and
the invisible rays at the violet end of
the solar spectrum.
An infectious disease is one which
may be contracted by the introduction
into the living body of living disease
germs, which may be contained in
different kinds of infectious material.
Thus the disease germ (bacillus)
which produces diphtheria is contain
ed in the "exudate" or false men,
brane" deposited in the throat or
nasal passages of those suffering from
this disease, and the material cough
ed up by a patient with diphtheria is
infectious material. In cholera and
in typhoid fever the discharges from
the bowels contain the germs and are
consequently infectious material.
Now, the object of disinfection is
to prevent the extension of infectious
diseases by destroying the specific in
fectious agents-germs-which give
rise to them and this is accomplish
ed by the use of disinfectants. Hav-
ing, as hope, made this clear.
Any chemical agent which destroys
or masks bad odors is commonly spo-
ken of as disinfectaht, and there are
large number of so called "disinfec-
tants'' in the market which are sim
ply deodorants and which are entire
ly untrustworthy for the destruction
of infectious material-that is, mate
rial containing living disease germs.
These disease germs belong to the
class of low vegetable organisms
microscopic plants-kpown as bacte-
ria, which as rule thrive better in
the darkness than when exposed to
daylight, and some of them are quick
ly destroyed by exposure to direct
sunlight. In experiments made by
me in 1898 it was demonstrated that
the cholera bacillus is infa1libly killed
by exposure to direct sunlight for an
hour or two, and the distinguished
German bacteriologist, DIR. Robert
Koch, has shown that the bacillus of
consumption-tubercle bacillus : is
destroyed by similar exposure in a
time varying from few minutes to
several hours, depending upon the
thickness of the layer material in
which it is imbedded.
AS a result of this it is evident that
the material coughed up by patients
with consumption and containing tu-
becle bacilli in vast number is far
less dangerous to the community in
regions where the patient can live out
of doors and where the sun shines
nearly every day in the year.
Some disease germs which are not
killed outright by exposure to the
suns rays are greatly restrained in
their development. This is true of
the bacillus of typhoid fever. AL
though it has been shown by care
fully conducted experiments that GER
tain disease germs are promptly de-
stroyed by the luminous radiations
from the sun, and especially by those
at the violet end of the solar spectrum,
it is also true that the heat rays play
an important part in the destruction
Of harmful bacteria.
This is partly due to the fact that
certain disease germs are quickly de-
stroyed by being deprived of all mois-
ture-by desiccation. Thus the germs
of cholera and of pneumonia quickly
perish when completely dried.
Other germs, however, as those of
typhoid fever, of diphtheria and OF
consumption, may retain their vitality
in a dried condition for several
months. But the germs of all these
diseases are destroyed by a compara-
lively low temperature. In expert
ments which made several years age
1 ascertained that the germs of pneu-
monia and of cholera were killed by
exposure for a few minutes to a tenn
perature of I26 degrees F.
A still lower temperature is affec-
tive if the time of exposure is pro-
longed. It is therefore evident that
prolonged exposure to the direct ray:
of the sun would destroy these germ:
independently of the disinfecting pow
er or germicidal action of the lumin.
Gus rays or the fatal results of desic
cation.
Other disease germs require high
er temperature for their destruction
The typhoid bacillus and the bacillu:
Of diphtheria are killed by exposure
to a temperature of I4o degrees F
for ten minutes. In general, it may
be stated that this temperature i:
fatal to all the most important dis
ease germs.
The facts stated furnish a scientif
ic basis for practical disinfection, anC
it is evident that when sunshine i!
available no chemical agents are es
sential for the destruction of disease
germs. Any article of food or drink
which has been heated for few min
utes to something near the boiling
point of water is absolutely safe, 81
far as any danger from disease germ.
is concerned, and any article of cloth
ing which has been put through the
ordinary operations of the laundry i
as safe as if it had been placed for ar
hour in an expensive steam disinfec
tor or immersed in a strong disinfect
ing solution.
1t will be seen that scientific inves
LEGATIONS fully justify the practice 0
good housewives, who at frequent in
tervals expose their blankets and arti
cles of wooden clothing, which canno
be placed in boiling water without in
jury, to prolonged sun bath, wh'
scald out milk pans and kitchen uten
sils aud place them in the sun to DIR,
and who open up their sleeping apart
ments for the admission of sunligh
and fresh air. = Surgeon Genera