3
Liebermeister says : " When typhoid fever is oriceestablised'in any locality, it may
disappear for a long while and then suddenly reappear without the introduc-
tion of a new case." "Infection, says the same. author, " can be produced by
the air we breathe and the water we drink".
The usual modes of propagation are thus given by Aitken :—
" By. percolation through the soil into the wells which supply drinking water to the
inhabitants; (2) by issuing through defects in the sewers into the air of an inhabited area;
(3) by exhalation through the aperture of small ill-trapped water closets or privies which are
at once the receptacles of the discharges from the sick and the daily resort of the healthy;
(4) by overflow water-pipe connections between drinking water cisterns and the drain; (5) by
contamination of milk from a polluted water source."
Other medical men, however, are not satisfied with the hypothesis that every
case of enteric fever is of specific origin, and hold with Murchison, who, in his
great work on continued fevers, lays down that it may originate spontaneously
or de novo, and that " enteric fever is traceable to air or drinking water polluted
with the products of decomposing sewage or other forms of putrefying animal
matter". This is known as the Pythogenic (Filth-begotten) Theory. Dr.
Murchison makes the following remark, which is very valuable to sanitary
officers in India :—
" In connection with the discussions which have taken place on the origin of enteric
fever it is not immaterial to observe that there is an analogy on many points between enteric
fever and diseases acknowledged to be malarious : a, the prevalence of both varies with
season, temperature, &c.; b, recent residence predisposes to both; c, both only prevail under
certain known infractions of sanitary laws; d, the quality of the poison varies with the
locality. The varieties of small-pox and scarlatina can be proved to be due not to any
difference in the quantity or the quality of the poison, but to the varying constitutions of the
recipients. On the other hand, the varieties' of malarious remittent fever are due in a great
measure to the dose of the poison or the locality where this has been generated, and the same
remark applies to enteric fever.
" The etiology of enteric fever may be thus summed up :—
1. Enteric fever is an endemic disease, or its epidemics are circumscribed.
2. It is most prevalent in autumn and after hot weather.
3. It is independent of overcrowding and attacks the rich and poor indiscriminately.
4. It may be generated independently of a previous case by fermentation of fæcal and
perhaps other forms of organic matter.
5. It may be communicated by the sick to persons in health ; but even then the poison
is not like that of small-pox given off from the body in a virulent form, but is
developed by the decomposition of the excreta after their discharge.
6. Consequently an outbreak of enteric fever implies poisoning of air, drinking water,
or other ingesta with decomposing excrement."
Dr. Richardson, one of the greatest living authorities on hygiene, dissents
entirely from the germ theory and contends that " the poisons of the various
communicable diseases are modified secretions, and thus, though products of
living organs, are not themselves living but really dead matter, and that
different diseases are caused by secretions of different glands ". In his report
on the sanitary condition of Brighton, published in the Lancet of November 4th,
1882, he says :—
" There is a dispute among the learned regarding the nature of the exciting organic
particle as to whether it be living or dead, or whether it comes from without or from man
himself. It is sufficient for the present practical purpose to know that the particle is
necessary as a factor in an epidemic outbreak; that, as a rule, to which there are few
exceptions, it passes from affected. persons, and in those who are susceptible to it, it
produces disease if it reaches them. The particle is absorbed by the susceptible; it is, as it
were, planted in them; and after a certain definite period, called the period of incubation, it
causes in them phenomena or symptoms which are the same as were presented in the person
from whom it was derived."
And, again:—
" The disease called typhoid fever is one of those affections which can be conveyed
extensively by food or drink in any community after the accident of its introduction and in
ignorance of its danger. The organic exciting particle or poison of typhoid is usually, and as
many think always, conveyed by fluids taken into the body as drink. The poison may possibly
be conveyed for a short distance by the air; but so little is this event feared, that in some
hospitals for the sick typhoid patients are allowed to remain in the general wards separated