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BLACKWATER FEVER 
By J. W. W. STEPHENS, M.D., Cantab. 
WALTER MYERS LECTURER IN TROPICAL MEDICINE, LIVERPOOL 
I. THE DISTRIBUTION OF BLACKWATER FEVER 
ONE of the commonest objections urged against the malarial origin of blackwater 
is that the distribution of blackwater and malaria is not identical. But it is 
equally true that the distribution of mild malaria and severe malaria is not 
identical, and the conclusion that blackwater is non-malarial is, for this reason alone, 
by no means justifiable. Thus, for instance, the mortality from malaria in the few 
still remaining foci of Northern Europe is not on a par with that of the Roman Cam- 
pagna, nor again is the severity of malaria in Northern Italy and Austria at all com- 
parable with that in Southern Italy and Sicily. Thus, Schaudinn 1 says, ' in I stria (on 
the Adriatic) the "tropica" always is very mild. There are no records of deaths, 
which are frequent in Italy.' The aspect of the 'virulence' of a particular species 
of parasite has, in this argument, been overlooked, and we cannot speak vaguely of 
malaria as a whole. The factors which determine ' virulence ' of a parasite are almost 
entirely unknown. Those factors which constitute the climate of a country are, in all 
probability, the determining factors also of ' virulence,' whether this results from 
altered ' virulence ' of the parasite itself or from altered blood conditions of the 
patient or from both. 
In this paper, then, I propose to consider the distribution of blackwater fever, 
with a view to shewing that, so far as the data allow, there is a close correspondence between 
that of blackwater fever and of severe malaria. I do not propose to argue therefrom 
that blackwater fever is malarial, because the proof of this statement is not merely a 
matter of argument, but is based on definite facts. To these I shall return in a sub- 
sequent article. We may first consider the United States as here the data, more 
especially those regarding malaria, are sufficiently complete for a comparison to be 
made. 
According to Hirsch, 2 the first records of blackwater fever in the United 
States date from 1866, in Texas and Louisiana, and subsequently in Mississipi, 
Arkansas, North Carolina. Davidson 5 gives the same list, Georgia, however, instead of 
Arkansas. Weber 4 mentions Alabama, Mississippi, Louisiana, Arkansas and also Florida, 
a 1 
