PLEURO-PNEUMONIA.

The cattle plague, which is creating so much anxiety throughout the

Eastern States, is a contagious fever, affecting cows chiefly,

characterized by extensive exudations into the respiratory organs, and

attended by a low typhus inflammation of the lungs, pluræ, and

bronchia. It has prevailed in Europe for ages, at times developing

into wide-spread scourges, causing incalculable loss. It was imported

into England in 1839, and again three years later; and it was

estimated that within twenty-five years thereafter the losses by

deaths alone in England had amounted to $450,000,000. In 1858 the

disease was carried to Australia by an English cow, and, spreading to

the cattle ranges, almost depopulated them.

In 1843 an infected Dutch cow brought the disease to Brooklyn, where

it has since lingered, slowly spreading among the cattle in Kings and

Queens counties. In 1847 several head of infected English cattle were

imported into New Jersey, and, spreading among a herd of valuable

cattle, made it necessary for them all to be slaughtered, the only

certain method of stamping out the disease. In 1859 four infected cows

were imported into Massachusetts from Holland; the plague spread

rapidly, and was stamped out only by persistent effort, the State

paying for over 1,000 slaughtered cattle. Since 1867 the disease has

not been known there. Meantime the pest had invaded Eastern

Pennsylvania, Delaware, and Maryland, where it has since prevailed in

isolated localities. The absence of large herds of moving cattle in

these districts, except for speedy slaughter, has prevented the

disease from developing into a general plague.

The recent action of the British Council in forbidding the importation

of American live cattle is likely to prove of inestimable benefit to

this country, in forcibly calling attention to the grave risk that the

presence of the disease on Long Island and elsewhere constantly

entails. Fortunately the drift of the cattle traffic is eastward, and

as yet there has been no propagation of the poison in the great cattle

ranges of the West. Unless summarily arrested, however, the disease

will surely reach those sources of our cattle supply, and occasion

losses that can be estimated only in hundreds of millions of dollars.

The experience of all countries into which this disease has gained

access appears to prove that there is only one way of getting rid of

it--namely, the immediate killing of all infected cattle, and the

thorough disinfection of the premises in which they are found.

The disease is purely infectious, and is never found in regions where

it has not gained a foothold by importation. Palliative measures have

in every instance failed to eradicate the disease, and are only

justifiable, as in Australia, after the plague has reached dimensions

utterly beyond the reach of any process of extermination.

Professor Law, of Cornell University, one of our best informed

veterinary surgeons, most emphatically opposes every attempt to

control the disease by quarantining the sick or by the inoculation of

the healthy. "We may quarantine the sick," he says, "but we cannot

quarantine the air." To establish quarantine yards is simply to

maintain prolific manufacturers of the poison, which is given off by

the breath of the sick, and by their excretions, to such an extent

that no watchfulness can insure against its dissemination. Besides,

the expense of thorough quarantining operations would amount to more

than the value of the infected animals whose lives might be saved

thereby. Inoculation is still less to be tolerated at this stage of

the pest.

The Professor says: "Germany, Holland, Belgium, France, and England,

have been treating the victims of this plague for nearly half a

century, but the result has only been the increase of disease and

death. Our own infected States have been treating it for a third of a

century, and to-day it exists over a wider area than ever before.

Contrast this with the results in Massachusetts and Connecticut, where

the disease has been repeatedly crushed out at small expense, and

there can be no doubt as to which is the wisest course. As all the

plagues are alike in the propagation of the poison in the bodies of

the sick, I may be allowed to adduce the experience of two adjacent

counties in Scotland when invaded by the rinderpest. Aberdeen raised a

fund of £2,000, and though she suffered several successive

invasions, she speedily crushed out the poison wherever it appeared by

slaughtering the sick beasts and disinfecting the premises. The result

was that little more than half the fund was wanted to reimburse the

owners for their losses, and the splendid herds of the county were

preserved. Forfar, on the other hand, set herself to cure the plague,

with the result of a universal infection, the loss of many thousands

of cattle, and the ruin of hundreds of farmers. Finally the malady was

crushed out in the entire island by the method adopted by Aberdeen and

other well advised counties at the outset."

And again, "Cattle have been inoculated by the tens of thousands in

Belgium and Holland, and of all Europe these are the countries now

most extensively infected. France, Prussia, Italy, Austria, and

England have each practiced it on a large scale, and each remains a

home of the plague. Australia has followed the practice, and is now

and must continue an infected country. Our own infected States have

inoculated, and the disease has survived and spread in spite of it,

and even by its aid. Whatever country has definitively exterminated

the plague (Norway, Sweden, Denmark, Holstein, Mecklenburg,

Switzerland, Massachusetts, and Connecticut), that country has

prohibited inoculation and all other methods that prevail on the

principle of preserving the sick, and has relied on the slaughter of

the infected and the thorough disinfection of their surroundings. So

will it be with us. If any State adopts or allows any of these

temporizing measures, that State will only repeat the experience of

the past alike in the Old World and the New, will perpetuate the

disease in the country, will entail great losses on its citizens, will

keep up the need for constant watchfulness and great expense by the

adjoining States for their own protection, and will indefinitely

postpone the resumption of the foreign live stock trade, which, a few

months ago, promised to be one of the most valuable branches of our

international commerce."

We are persuaded that the position taken by Professor Law, and other

similar-minded veterinary surgeons, is the only safe one. The disease

can be stamped out now with comparatively small loss. If trifled with,

and tolerated, it cannot but result in a great national calamity.

* * * * *

Scientific American, Volume 40, No. 13, March 29, 1879 A Weekly Journal of Practical Information, Art, Science, Mechanics, Chemistry, and Manufactures · 第 24 / 162 题