MAN AND THE GNAT.
Almost at the beginning of their great task the Americans were faced
with a problem which involved the success or failure of the whole
enterprise. I have said something about the climate and health
conditions at the isthmus. It is fairly certain that yellow fever and
malaria would have wrecked the French undertaking even if there had been
no other obstacles to its success. It is not less probable that if the
Americans had been in no better a position to wage war with these
plagues, their work at the isthmus would also have been in vain. The
French had built excellent hospitals and provided efficiently for the
comfort and recovery of those who were stricken with these diseases. But
being totally ignorant of the sources and method of transmission of
malaria and yellow fever, they could do nothing effectual in the way of
prevention and eradication. They could only take the individual victim
when they found him and do their best to cure him. They still believed
that malaria was produced by climatic conditions, by marshy emanations,
mists, and so forth. The fleecy clouds which gather round the isthmian
hills in the rainy season were given the very undeserved title of "the
white death" by the French workers at the isthmus. Yellow fever, again,
was just as mistakenly attributed to the climate, and especially to
filthy ways of living. It is not surprising that, with these
misconceptions, medical skill should have been almost useless during the
French occupation, and that the employees at the isthmus should have
died in their thousands.
But since the days of the Lesseps company, science had thrown a flood of
light on the nature of these tropical scourges and the secret of their
transmission. As these medical and scientific pioneers made a Panama
Canal possible, though their names are not directly linked with its
construction, we may look back for a few moments at their triumphs of
discovery. The credit for first discovering that malaria is not due to
poisonous emanations or contagion but is carried from people infected
with the disease by the _anopheles_ mosquito belongs to Major (now Sir)
Ronald Ross, formerly of the Indian Medical Service, who devoted himself
to this subject during the last years of the 19th century. By a series
of experiments he proved that malaria is due to the presence in the
human blood of an organism which is conveyed from person to person by
this mosquito, and that the mosquito is harmless unless it has become
infected with the germ by biting a person who has caught malaria. The
value of this discovery was soon shown by practical applications. Major
Ross was engaged by the Suez Canal Company to deal with the malaria
which had become firmly established at Ismailia, a little town of 10,000
inhabitants on that canal. No fewer than 2,500 cases had been supplied
in one year by this small population. The new methods founded on the new
discovery proved so effectual that in three years the disease was
stamped out, and there has been no relapse ever since. The same results
were achieved at Port Said.
Now, if malaria is thus caused by mosquito bite, there was some _a
priori_ reason for thinking that yellow fever might be transmitted in
the same way. At any rate the insect was again laid under a very grave
suspicion. The opportunity for studying this further question was
afforded during the Spanish-American war, when a serious outbreak
occurred among the troops occupying Havana, in Cuba. The doctors were
quite unable to deal with this most terrible of all diseases. Knowing
nothing whatever of its cause, their treatment of it could be only
experimental and casual. So a board of inquiry was formed consisting of
four army surgeons serving in Cuba--Walter Reed, James Carroll, Jesse W.
Lazear, and Aristides Agramonte. The experiments were begun in June
1900, and continued into the next year. Of these four, Dr. Agramonte was
not liable to the disease, and Dr. Reed was called away on duty to
Washington. The other two determined to experiment on their own persons
rather than risk the lives of other people.
Dr. Carroll first allowed himself to be bitten by the mosquitoes, not
the _anopheles_ but another variety known as the _stegomyia_. He fell
ill with a bad attack of yellow fever, which very nearly cost him his
life. Later, in the yellow fever hospital, Dr. Lazear deliberately
allowed a mosquito to feed on his hand. In four days he was down with
the disease in so acute a form that he died of it--a true martyr, if
ever there was, to the cause of science and the welfare of mankind.
These and other experiments proved conclusively that yellow fever, like
malaria, is transmitted by mosquito bites, but it was still uncertain
how soon after biting an infected person the mosquito becomes itself
harmful and how soon a person stricken with malaria is able to infect a
healthy mosquito. So further experiments were necessary, and volunteers
were invited to offer themselves for this service. Everybody in the army
knew what had happened to Doctors Carroll and Lazear, but in spite of
this plenty of willing martyrs appeared. The first to present themselves
were two young soldiers from Ohio, John R. Kissinger and John J. Moran.
Dr. Reed talked the matter over with them, explaining fully the danger
and suffering involved, and stating the money consideration offered by
General Wood. Both young men declared that they were prepared to
undergo the experiment, but only on condition that they should receive
no pecuniary reward. When he heard this declaration, Dr. Reed touched
his hat with profound respect, saying, "Gentlemen, I salute you!"[8]
Kissinger took the disease from the mosquito bites, and recovered. A
room was prepared for Moran, a sort of mosquito den into which fifteen
gnats, all suffering from yellow fever, had been admitted. Major Reed
describes what happened:--
At noon on the same day, five minutes after the mosquitoes
had been placed therein, a plucky Ohio boy, Moran by name,
clad only in his night-shirt and fresh from a bath, entered
the room containing the mosquitoes, where he lay down for a
period of thirty minutes. Within two minutes of Moran's
entrance he was being bitten about the face and hands by the
insects, that had promptly settled down upon him. Seven, in
all, bit him at this visit. At 4.30 p.m. the same day, he
again entered and remained twenty minutes, during which time
five others bit him. The following day, at 4.30 p.m., he
again entered and remained fifteen minutes, during which
time three insects bit him; making the number fifteen that
had fed at these three visits. On Christmas morning, at 11
a.m., this brave lad was stricken with yellow fever, and had
a sharp attack, which he bore without a murmur.
But still the demonstration was not complete. It was necessary to prove
by equally undeniable evidence that yellow fever is not conveyed by
contagion with the clothes and persons of infected people. These
experiments were even more trying and heroic than those which preceded.
A small wooden hut, 14 by 20 feet, was prepared, and into this was
stored a large amount of bedding and clothes which had been used and
worn by persons suffering from the fever. The building was carefully
guarded against the intrusion of mosquitoes, and a temperature of
seventy-six degrees, with a sufficient moisture, maintained. For twenty
consecutive days Dr. Clarke and his men went into this room, handled,
wore, and slept in the contaminated clothing, although the stench was so
offensive as to be almost appalling. They emerged from the ordeal in
perfect health, proving beyond possibility of dispute that the disease
was not contagious, and that the mosquito was the sole method of
transmission.
When distributing the credit for the new channel of world-traffic
through the isthmus of Panama, let us not forget Dr. Lazear who
sacrificed his life and the many others who cheerfully risked their
lives to establish truths and facts without which the construction and
continued operation of the canal would almost certainly have been
impossible.
One mosquito may look very much like another, but the _stegomyia_ and
the _anopheles_ differ in many important respects. The latter finds its
most favourable breeding-places in stagnant pools of fresh water, such
as are left by the heavy rains of the isthmus. It is essentially a gnat
of the country-side. The _stegomyia_, on the other hand, inclines to a
more frivolous town life. Cisterns and tanks and other receptacles for
storing water are his favourite haunts. In length of life and power of
flight the species also differ, though these details are not yet fully
ascertained. The _stegomyia_ is said to live three months. Dr. Cornish
states that it becomes dangerous only by attacking man during the first
three days of yellow fever, and that, even then, twelve days elapse
before its bite is infectious. Six days after a man has been bitten by
an infected _stegomyia_ he falls ill with yellow fever, and for the next
three days he is capable of transmitting it to the healthy mosquito. Mr.
Bishop informs us that if there is no fresh case of yellow fever within
a period of sixty days after the latest one in an epidemic, it is a safe
conclusion that the disease has been stamped out, because there is no
mosquito alive to carry the parasite. After a period of ninety days all
doubt on the subject is removed.[9] If a community, therefore, which has
thus got rid of its last case of yellow fever could be completely
isolated, yellow fever could never possibly return. It could only be
reintroduced from outside. It should be possible, with a proper system
of sanitation and quarantine, to free any district entirely from this
awful scourge.
The case of the _anopheles_ and his little contribution to human
suffering is very different. Whereas the victim of yellow fever either
dies or gets better and quickly ceases to be a source of infection to
the mosquito, the victim of malaria seldom dies of the disease, but he
remains infectious to the _anopheles_ for three years. The disease does
not simply attack new-comers or white people. Natives of the isthmus and
the West Indies are subject to it, and, indeed, seem to be in a
chronically malarious condition. It is said that 50 per cent. of the
population of the isthmus were found in 1904-5 to have the parasite of
malaria in their systems. It is difficult to estimate or imagine the
part played by this widespread malady on conditions of life and
civilization within the tropics.
Sir Ronald Ross, the greatest living authority on the subject, made some
interesting remarks in an address at the Royal Colonial Institute in
January of this year. He said:--
Nothing has been more carefully studied of recent years than
the existence of malaria amongst indigenous populations. It
often affects every one of the children, probably kills a
large proportion of the new-born infants, and renders the
survivors ill for years; only a partial immunity in adult
life relieves them of the incessant sickness. Here in Europe
nearly all our children suffer from certain
diseases--measles, scarlatina, and so on. But these maladies
are short and slight compared with the enduring infection of
malaria. When I was studying malaria in Greece in 1906, I
was struck with the impossibility of conceiving that the
people who are now intensely afflicted with malaria could be
like the ancient Greeks who did so much for the world; and I
therefore suggested the hypothesis that malaria could only
have entered Greece at about the time of the great Persian
wars. One can scarcely imagine that the physically fine race
and the magnificent athletes figured in Greek sculpture
could ever have spent a malarious and splenomegalous
childhood. And, conversely, it is difficult to imagine that
many of the malarious natives in the tropics will ever rise
to any great height of civilization while that disease
endures amongst them. I am aware that Africa has produced
some magnificent races, such as those of the Zulus and
Masai, but I have heard that the countries inhabited by them
are not nearly so disease-ridden as many of the larger
tracts. At all events, whatever may be the effect of a
malarious childhood upon the physique of adult life, its
effects on the mental development must certainly be very
bad, while the disease always paralyzes the material
prosperity of the country where it exists in an intense
form.
The isthmus of Panama was beautifully adapted to the breeding of the
_anopheles_ and the widest dissemination of malaria. In fact, the canal
zone taken over by the Americans was perhaps the most malarial strip of
territory in the world. The heavy rains leave the country covered with
those marshes and pools from which these little ghostly insects are
always rising in swarms, ready to carry the germs of disease from the
sick to the healthy and thus perpetuate and extend the domain of this
distressing malady. The reader will notice that, as the yellow fever
victim is only infectious to the mosquito for three days, while the
malarial person can convey the poison for three years, it is a much more
practical problem to eradicate yellow fever than to stamp out malaria.
It is true the causes of malaria are now fully known and the only
effective methods of propagation ascertained. If one could isolate all
malarial patients, including all who are capable of transmitting the
disease, in buildings screened with fine copper-gauze to keep out the
mosquitoes and thus gradually diminish the area of infection to
vanishing point, it would not be necessary to deal with the
breeding-places of the mosquitoes, and man and the gnat might live
together in perfect amity. But with fifty and even seventy per cent. of
the people malarially infected, such a heroic course is obviously
impossible, and one can hope only to diminish to a considerable degree
the prevalence of the disease.
The first two and a half years of the American occupation of the isthmus
was spent in looking round and preparing for the great work. It soon
became evident that the most pressing and immediate task was one of
cleaning up and sanitation. In July 1904, Colonel W. C. Gorgas, whose
name will always be associated with the triumphs won over disease at the
isthmus, became the head of the department of sanitation under the Canal
Commission. He quickly recognized that everything depended on the
efficiency and success of his own department. "The experience of our
predecessors," he wrote, "was ample to convince us that unless we could
protect our force against yellow fever and malaria we would be unable to
accomplish the work."[10] When the Americans took over, yellow fever,
though present, was quiescent, but the figures began almost at once to
mount up. In December 1904 there were six cases on the isthmus and one
death. In January 1905 there were nineteen cases and eight deaths, seven
and one respectively among the canal employees. In May there were
thirty-three cases, twenty-two on the canal, with seven deaths in all,
including three employees. In June there was an alarming advance.
Sixty-two cases occurred on the isthmus, thirty-four of them among the
employees. There were nineteen deaths, six on the canal. Something like
a panic then set in among the Americans engaged on the canal works. Many
threw up their positions, and the homeward-bound steamers were filled
with employees fleeing from this real "yellow peril." In the annual
report of the Commission for 1905 we read:--
A feeling of alarm, almost amounting to panic, spread among
the Americans on the isthmus. Many resigned their positions
to return to the United States, while those who remained
became possessed with a feeling of lethargy or fatalism,
resulting from a conviction that no remedy existed for the
peril. There was a disposition to partly ignore or openly
condemn all preventive measures. The gravity of the crisis
was apparent to all.
This loss of moral tone was the most dangerous symptom of all. A feeling
of "let us eat and drink, for to-morrow we die" gained possession of
the canal workers, and in the indifference of despair many tore down the
nettings over the windows of the canal building and began to neglect all
the sanitary precautions enjoined on them by the department. Evidently a
calamity was in prospect which would have brought to an end, perhaps for
ever, American canal ambitions at the isthmus. The restoration of public
confidence and sense of responsibility seems to have been due largely to
Mr. Charles E. Magoon, governor of the canal zone. He set himself to
rebuke and remove the morbid bravado then prevailing. "He began by
frankly and publicly declaring that he, personally, was afraid of the
fever, and that in his opinion all non-immunes who professed not to be
afraid were 'talking rot!' Then he ordered all the window-screens to be
repaired and kept in place, and announced that if any man was caught
leaving them open or tearing holes in them, something uncommonly
unpleasant would happen to him. Now when a man of Judge Magoon's mental
and physical stature admits that he is afraid, any lesser man is a fool
to say he isn't; and when a man of Judge Magoon's resolution gives an
order and prescribes a penalty for its violation, that order is very
likely to be obeyed."[11]
[Illustration: _Clinedinst--Washington, D.C._
COL. WILLIAM C. GORGAS,
Medical Dept., U.S. Army, Head of the Department of Sanitation,
Ancon.]
Governor Magoon arrived at the isthmus in May 1905, just as the yellow
fever epidemic was reaching its climax. From that moment he and Colonel
Gorgas, to whom he gave the most complete support, set themselves to
fight the fever. The first thing to do was to get all the patients
within screened buildings, whether the hospital or their own homes, so
that no _stegomyia_ mosquitoes could saunter in and take the poison.
Then the towns of Colon and Panama were handed over to a campaign of
spring-cleaning such as the world has never witnessed. Then the canal
building was thoroughly fumigated with pyrethrum powder or sulphur, and
not simply the official building but every single house in the city of
Panama was similarly disinfected. Dust and refuse were everywhere burnt.
A very efficient system of inspection was adopted, and a rigid
quarantine enforced against all foreign places whence the yellow plague
could be imported into the zone.
But more important than the immediate expedients were the more
permanent sanitary improvements carried out in Colon and Panama. These
towns were repaired with brick or cement, and provided with what they
had never yet enjoyed, a proper system of drainage. Waterworks were also
constructed outside the towns, and a supply of pure water made available
for every household. Hitherto water had had to be stored during the dry
season in tanks and cisterns, in which the _stegomyia_ mosquito revelled
exceedingly. These were now no longer necessary, and stagnant water,
wherever it collected in the town, was drained away. In order to
expedite these splendid reforms, Governor Magoon withdrew the workers
from the canal and concentrated all efforts on the sewers and
waterworks. So speedily was the work carried forward that the water was
turned on for public use from the main in the Cathedral Plaza on July 4.
The results of this drastic campaign were soon apparent in the dwindling
of the yellow fever returns. In July there were still forty-two cases
and thirteen deaths on the isthmus, with twenty-seven cases and ten
deaths among the employees. August showed a great improvement, with
twenty-seven cases and nine deaths on the isthmus, and twelve cases and
only one death on the canal. The improvement continued through
September, October, November, and in December only one case was reported
on the isthmus and one on the canal. Three months having elapsed since
the last case, and, therefore, every _stegomyia_ which could possibly be
infected with malaria having departed this life, the epidemic was
entirely past and over. As I have pointed out, there cannot possibly be
any return of it under these conditions unless the infection is brought
from without. And if any new cases are at once isolated and screened
from afternoon calls of the mosquito, the outbreak may be easily and
infallibly suppressed. We may say, therefore, that the yellow spectre at
the isthmus has been shorn of all its terrors.
Malaria is, however, a very different proposition. A corresponding
crusade has been carried on for six years against the little _anopheles_
gnat, the little criminal who carries the malarial poison. His happy
breeding-grounds are in open country marshes and pools, and there is no
lack of these in the canal zone. It was impossible to deal with the
entire three-quarters of a million acres of that territory, but wherever
the canal workers were settled determined war was waged against the
mosquitoes. It should be remembered that the _anopheles_ can fly only
about a hundred or two hundred yards. The jungle was therefore cleared
away for a few hundred yards round each village and settlement, marshes
and pools in this area were drained off, and into all the ditches where
stagnant water had collected oil was poured, which so effectually turns
the mosquito's stomach that it never recovers. Some 1,200 acres of the
zone were thus treated, and of course the regulations as to
house-screening applied to malaria no less than to yellow fever. The
employees were also supplied freely and generously with quinine.
The result has been not the eradication of malaria, but the reduction of
the cases to about one-third the number at which they stood in 1906. Yet
even so, among the 40,000 employees on the canal during the year ending
June 30, 1912, there were 7,000 malaria cases in the hospitals, with 32
deaths, 22 of these being white people. The heavy rainfalls at the
isthmus will probably prevent the complete sanitation of the country in
this respect, for the simple reason that the destruction of the
_anopheles_ mosquito or the eradication of the malarial germ can never
be complete. There will always be people going about with the malarial
organism in their blood, and always _anopheles_ mosquitoes ready to
become infected with it and to carry the infection about. But, as we
have seen, much can be done by the means described to reduce the ravages
of the disease. In 1906, out of a working force of 26,000, there were
21,739 cases of malaria. We have seen how this figure had been brought
down in 1912. In 1906 it was almost certain that any white person coming
to reside at the isthmus would catch malaria. Now it is quite possible
to live there in perfect health, quite free from any malarial infection.
It may be useful to mention that the entire death-roll among the
employees on the Panama Canal and railway from the American occupation
down to June 30, 1912--that is, about eight years--was 5,141, of whom
284 were Americans. Of this total, 4,119 died of disease and 1,022 from
violence or accident. During the same period 49 American women and 87
American children died.[12] Sir Ronald Ross, as I have said, was told by
the British Consul at Panama in 1904 that the French lost in the nine
years of their occupancy some 50,000 lives, principally from malaria and
yellow fever. This may be an over-estimate, but there is no doubt that
the American figure shows an enormous improvement on the French.
It is easy to conclude that what has been done in sanitation at the
isthmus of Panama may be done anywhere else in the tropics, where
malaria and yellow fever prevail. That may be true, but we must also
remember that the work of Panama had behind it all the wealth and
resources of a mighty republic of 90,000,000 citizens. The expenditure
on these hygienic purposes at the isthmus has been enormous, though not
a penny has been wasted. Down to the end of December, 1912, the total
outlay of the Department of Sanitation was $15,500,000. Waterworks,
sewers, etc., accounted for another $2,500,000, so that we get a grand
total expenditure on sanitation of $18,000,000. This will certainly rise
to $20,000,000 before the canal is finished, so that for the ten and a
half years of its construction there will have been an annual
expenditure for all health purposes of $1,900,000. It is not likely that
there will be many tropical areas of this kind with so large a sum
available for the luxury of scientific sanitation. Again, it must be
noticed that the administration had special advantages at the isthmus.
It exercised something like military authority. It had absolute powers
of deportation, and could enforce its regulations as it pleased. And in
considering the statistics it must also be borne in mind that not only
the physical but the moral and mental health of the work-people at the
isthmus was promoted in every way. We shall look into the life of the
Panama construction camps in the next chapter. The social interest and
amusement provided for the employee must have counted for something
beside the sewering and screening and mosquito-hunting. All the same,
the success achieved at Panama is full of hope and promise for tropical
life in the future. Colonel Gorgas writes encouragingly:--
I think the sanitarian can now show that any population
coming into the tropics can protect itself against these two
diseases (malaria and yellow fever) by measures that are
both simple and inexpensive; that with these two diseases
eliminated life in the tropics for the Anglo-Saxon will be
more healthful than in the temperate zones; that gradually,
within the next two or three centuries, tropical countries,
which offer a much greater return for man's labour than do
the temperate zones, will be settled up by the white races,
and that again the centres of wealth, civilization, and
population will be in the tropics, as they were in the dawn
of man's history, rather than in the temperate zone, as at
present.
Apart from the question of disease, it is far from certain that the
white man can ever remain as "fit," as capable of bodily labour, in
equatorial regions as in his native temperate conditions, or that his
descendants will also maintain the same standard of health and strength.
Ordinary non-professional opinion would perhaps discount Colonel
Gorgas's forecast as a little too optimistic.
FOOTNOTES:
[8] "Sanitation of the Isthmus." Mr. J. B. Bishop in _Scribner's
Monthly_, February 1913.
[9] _Scribner's Monthly_, February 1913, p. 248.
[10] _Journal American Medical Association_, July 6, 1907.
[11] "Four Centuries of the Panama Canal."
[12] See _Scribner's Magazine_, February 1913, p. 251.