Appx.

XIX. Investigating, etc., of infectious disease.

     2.  Interchange of Information .—Medical officers should work in the
closest possible collaboration with the Deputy Assistant Directors of
Hygiene and of Pathology and officers in charge of brigade laboratories,
and should also maintain touch with the civil public health authorities
of their station or district. They should arrange with the latter for
the mutual exchange of information as to the occurrence of infectious
disease in their respective spheres.

     3.  Lines of investigation.— In investigating outbreaks of infectious
disease the main inquiry should be directed to the known routes of
infection for the particular disease concerned and to the discovery of
a possible " carrier ". The possibility of cases having been missed,
either through errors in diagnosis or through failure of the patient to
report sick, should be borne in mind. Early information should be
obtained as to the movements of the first patients during the three.
weeks immediately preceding the onset of their illness. The subsequent
series of cases and its connection with the first cases or with a common
cause should be carefully traced, recorded in detail, and plotted out
on a spot map. Attention should be directed to any sanitary defects,
in the camp, barracks or their surroundings. Investigations should
be made regarding food, water, milk and other supplies, both official
and private; the method of disposal of refuse and excreta; over-
crowding and ventilation; the existence of breeding places of flies.
and other disease vectors, and their presence in excessive numbers.

     In reporting on the outbreak, reference should be made to methods
adopted for the isolation of the sick, segregation and observation of
contacts, disinfection, and other general sanitary measures which
have been taken.

     The early and accurate diagnosis of all cases of infectious disease,
and the isolation of patients, is of the utmost importance.

     4.  Disinfection.— As soon as possible after the removal of any case
of infectious disease, disinfection will be carried out as laid down in
paras. 533-554.

     In cases where isolation of the patient is effected in quarters,.
disinfection will be carried out immediately after the disposal of the
case.

     The following paragraphs give a synopsis of present knowledge
as to the methods of spread and necessary preventive measures in the
case of the principal diseases (arranged in alphabetical order).

ANTHRAX.

     5.  Spread.— By close association with infected cases, human or
animal, by carcases, hides, hair or bristles, by shaving or tooth brushes
containing spores. The route of invasion is commonly through
abrasions.

     6.  Preventive measures .—The patient should be isolated and dis-
infection carried out as indicated in para. 554.

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