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edge and adventure.
chapter 10
Felix d Herelle
Bacteriophages Discoverer
It began with a plague of locusts in the state of Yucatan, Mex-
ico. Felix d Herelle, a self-taught French-Canadian bacteriologist,
was working for the Mexican government in 1909 when locusts
began attacking the crops in the area. The local people told
d Herelle that there were places where the ground was strewn
with the corpses of these insects, as he wrote in an article trans-
lated by J. L. Crammer and published in Science News in 1949.
I went there and collected sick locusts, easily picked out since
their principle symptom was an abundant blackish diarrhoea.
This malady had not yet been described, so I studied it. It was
a septicaemia [septic shock caused by a rapid fall in blood
pressure] with intestinal symptoms. It was caused by bacteria,
the locust coccobacilli, which were present almost in the pure
state in a diarrhoeal liquid. I could start epidemics in columns
of healthy insects by dusting cultures of the coccobacillus in
front of the advancing columns: the insects infected them-
selves as they devoured the soiled plants.
Conducting a series of tests on the bacteria, d Herelle made
an observation that would later prove to be of great importance:
In the course of these researches I noted an anomaly, shown by
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204 It Doesn t Take a Rocket Scientist
some cultures of the coccobacillus which intrigued me greatly,
although in fact the observation was ordinary enough, so banal
indeed that many bacteriologists had certainly made it before on
a variety of cultures. The anomaly consisted of clear spots, quite
circular, two or three millimeters in diameter, speckling the cul-
tures grown on agar. Noticing something and following up on
it are two very different matters, however. Nineteen years later,
Alexander Fleming would have a similar experience. Fleming
noticed a mold growing in an uncovered petri dish at his labora-
tory; around the mold was a clear area. Analyzing the mold, he
discovered penicillin, although it would be another decade before
it became technically possible to produce the mold in sufficient
quantities to test it as an antibiotic. In a paper on his discovery,
however, Fleming suggested that it might have antibiotic proper-
ties, an aside that brought him the Nobel Prize along with the
two men whose work made commercial production possible,
Lord Florey and Ernst Chain. Like d Herelle, Fleming suggested
that others must have noticed the same kind of culture, but sim-
ply thrown it out as contaminated.
In 1909, d Herelle did not carry out any further experiments
on the anomaly he had noted, but he would return to it later
when he had more time for pure research. Throughout his life,
d Herelle was a wanderer, taking jobs where he could get them
and seldom staying put in one country or at a single institution
for more than a few years. Born in 1873 in Montreal, Quebec, he
was the only child of a wealthy French-Canadian father and a
Dutch mother. His father died when he was six, and his mother
then moved to Paris. William C. Summers of Yale University es-
tablished in his 1999 book, Felix d Herelle and the Origins of Molec-
ular Biology, that d Herelle s formal education never went beyond
high school, but he had a brilliant mind, and his mother s lar-
gesse made it possible for him to travel widely. Little is known
about his early life, and indeed there are holes even in the chro-
nology painstakingly established by Summers. As a young man,
Felix d Herelle 205
d Herelle developed an interest in bacteriology, and landed a job
in Guatemala City as a hospital bacteriologist in 1901. Questions
remain as to whether he passed himself off as a doctor or was
simply assumed to be one on the basis of his knowledge. He did
not treat patients, but taught at a medical school in Guatemala,
and would later state that he gained much of his scientific
grounding during the several years he spent in that country.
In 1907, d Herelle moved on to Mexico, working on the fer-
mentation of sisal, as well as serving as a government bacteriol-
ogist during a period when epidemics of yellow fever and other
infectious diseases were widespread. Shortly after his encounter
with the locusts, d Herelle returned to Paris to work at the Pas-
teur Institute. He made several journeys abroad over the next
few years, to Argentina, Turkey, and Tunisia, trying to use the
methods of locust control he had employed in Mexico, dusting
plants with the coccobacillus he had discovered. While in Tuni-
sia, he again encountered the clear spots in cultures that he had
first noticed in Mexico. Charles Nicolle, the director of the Pas-
teur Institute branch in Tunisia, later claimed to have suggested
to d Herelle that they were a virus.
Returning to Paris, d Herelle was put to work at the Pasteur
Institute on finding ways to control the deadly outbreaks of
dysentery that were felling so many World War I allied soldiers.
The cause of the dysentery was soon uncovered: Shigella bacte-
ria. Once again, clear spots showed up in cultures of dysentery
bacillus (rod-like bacteria). This time he followed through and
investigated them thoroughly. He recognized that the clear spots,
called plaques, were appearing because something was killing the
bacteria. A series of tests using the feces of a particular patient
produced more plaques on agar plates. (Agar is a jellylike carbo-
hydrate from seaweed that is not broken down by microorga-
nisms, and thus remains a solid neutral surface during the course
of an experiment.) The next step was to take a plaque and mix
it with a fresh culture of the bacteria in a flask.
206 It Doesn t Take a Rocket Scientist
The next morning, he would write toward the end of his
life, in the account published in 1949 in Science News, on open-
ing the incubator, I experienced one of those moments of in-
tense emotion which reward the research worker for all his pains:
at first glance I saw that the culture which the night before had
been very turbid, was perfectly clear: all the bacteria had van-
ished, they had dissolved away like sugar in water. As for the
agar spread, it was devoid of all growth and what caused my
emotion was that in a flash I understood: what caused my clear
spots was in fact an invisible microbe, a filterable virus, but a
virus which is parasitic on bacteria.
D Herelle gave his discovery the name bacteriophages phage
means to eat in Greek, thus giving us bacteria-eaters. They
are now generally referred to simply as phages. In his first paper
on the subject, published in French in 1917, he gave a more
sober account of the significance of his discovery. In summary,
he wrote at its conclusion, in certain convalescents from dys-
entery, I have shown that the disappearance of the dysentery
bacillus coincides with the appearance of an invisible microbe
endowed with antagonistic properties with respect to the path-
ogen bacillus. This microbe, the true microbe of immunity, is
an obligatory bacteriophage; its parasiticism is strictly specific,
but if it is limited to the species at a given moment, it may de-
velop antagonism in turn against diverse germs by accustomi-
zation. Here, d Herelle pointed toward the work that would
continue for the rest of his life: trying to find phages that could
be used against a variety of bacterial diseases. During 1917
1918, d Herelle noted thirty-four cases in which patients were
cured of dysentery when the appropriate bacteriophages he sup-
plied attacked the bacteria. If such applications of phages could
be extended to other diseases, it could provide medicine with a
potent new weapon.
Following the publication of this paper, it turned out that
the English biochemist Frederick Twort had made the same dis-
Felix d Herelle 207
covery in 1915. The superintendent of London s Brown Institu-
tion, Twort began experiments with viruses to determine if they
could thrive without a cellular host. He too used an agar plate.
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