View report page

26
particular, fattened on contaminated oyster-beds), ice
cream, watercresses, lemonade, etc. Special precautions
are now being taken with regard to milk-borne diseases
and oysters.
4. Direct Infection.—From person to person, or from soiled
linen, etc., of a typhoid patient, or want of cleanliness in
nursing a typhoid patient.
5. Pollution of Soil.—From a number of investigations it
appears that the Bacillus of Typhoid Fever can live in
the soil and possibly multiply there. In Clerkenwell for
various reasons this agency can have very little scope
It is difficult to say which of these five channels of infection is
most largely responsible for our high notification rate and death
rate for enteric fever. Inhalation of infected sewer air and pollution
of soil may, for various good reasons, be set on one side as
concerns Clerkenwell. Probably also infection through the water
supply may be considered as extremely unlikely, if not impossible.
It is well known that the London water supply is of a high degree
of purity. The Thames water unfiltered contains about 1,5002,000
microbes per cubic centimetre (i.e., about 20 drops) whilst
the New River water as delivered contains 8-10 microbes in 20
drops. The usual standard of purity accepted by bacteriologists
and water analysts is anything under 100 microbes per twenty
drops. So that the drinking water of the parish may be looked
upon as of very pure quality as regards bacteria. -Probably not
one of the 92 recorded cases of Typhoid Fever was derived from
our water supply. There is of course the further argument that if
the water supply was the cause of our high typhoid rate, we should
expect the disease to be more wide-spread. For the water supply
is common to the entire population.
From the distribution of the cases we must look for a cause
which is not common to the whole parish and which is not continually
operating. It is not unlikely that the cause of most of
the cases in Clerkenwell was either direct infection from a previous
case or infective food. It is difficult in a crowded population to