View report page

27
NOTES ON SMALLPOX.
Several medical practitioners in the Borough have stated that it would be of use to them
if a few notes on the. diagnosis of smallpox were circulated. I have therefore prepared
the following notes, setting out those points which appear to me to be of particular
value at the present time. I have placed the notes in what appears to me to be their
order of importance and in the form of the questions that occur to one when visiting a
suspected case. Some information as, for instance, incubation period and history of the
case, mode of onset, and so forth, obtained from relatives and friends may tend to
mislead, and this information should be regarded as corroborative. In "fact, the
diagnosis of smallpox depends not on one particular piece of evidence, -but on the
whole body of evidence.
IS THF. RASH A FACE AND LIMB RASH, OR A BODY RASH? This is a question
of the first and paramount importance. Smallpox is centrifugal, affecting the face,
and areas near the face, and limbs; it also affects irritated and exposed surfaces.
Chickenpox, though the face may be fairly heavily affected, is principally a body rash.
Smallpox is certainly infectious from the time of the appearance of the papular rash.
The distribution and the type of rash, aided by the corroborative evidence which can
always be obtained, should enable a diagnosis to be made in this papular stage of the
disease. Where the evidence is scanty, Consultant aid can be obtained by applying
to the Public Health Department.
WHAT IS THE DISTRIBUTION OF RASH ON THE BODY? Smallpox affects the
back more than the front, the shoulders more than the loins, the chest more than
the abdomen. Smallpox avoids the hollows, the flexures, and protected parts, it
attacks exposed or irritated parts.
WHAT IS THE CHARACTER OF THE RASH? A smallpox patient presents a rash
that may be described as homogeneous; it is roughly speaking papular at the same
time, vesicular at the same time; pustular at the same time. It is true that since the
rash comes out first on the face, the face at first may he more advanced than the
lower limbs, where it appears last, since the eruption is in an earlier stage on the
lower limbs, but the face, for example, should pass through papular, vesicular, and
pustular stages to be completely pustular on the sixth day, and pustulation is generally
complete over the whole body on the eighth day. There will not, for instance, be
present on the face, vesicles, pustules and scabs, neither will this phenomenon be
observed on any other region of the body, whereas in chickenpox, owing to "cropping,"
this phenomenon of a rash in different stages may be observed on the same region
of the body, as, for instance, on the face or the abdomen.
WHAT IS THE DEPTH OF THE RASH? Smallpox is a deep rash lying deep among
the epidermal cells, hence the "shotty" feel in the papular stage, which, however,
-should not be considered an all-important piece of information. The deep-seated pearly
look of the pustule on the hands or where the skin is thick is due to the deep-seated
focus of the lesion, whereas in chickenpox the rash is superficial, immediately under
the cuticle, and there are almost certain to be one or two of the fragile-looking
" glass" pocks or blister-like pocks, raised, obviously superficial vesicles, often of
varying shapes. Here again it must be remembered that a mild smallpox infection
tends to be more superficial than a severe infection.
HOW DID THE RASH DEVELOP? Smallpox first coming out on the face and wrists
and spreading principally over the limbs and areas near the face, the order of development
being face (especially forehead) and scalp, wrists, trunk and remaining parts of
upper extremities, lower extremities, develops generally through a regular progression
of papules, vesicles, and pustules, the rash generally becoming pustular after the fourth
day of the rash, that is to say, if the rash first appeared on the Sunday, it would
probably be vesicular on the Tuesday and Wednesday, and pustular from Thursday
to Sunday, beginning to dry on the Monday following. Chickenpox, on the other hand,
tends to be irregular in eruption and in maturation, many of the pocks maturing so
rapidly that they appear to begin .as vesicles. Here also it must be remembered that
the mild smallpox infection may not develop with such regularity, the rash maturing
more quickly than in a severe infection, but there will be the same sequence of
development.
WHAT WAS THE INVASION OR ONSET? It is, of course, an almost invariable
rule that immediately before the development of the rash in a case of smallpox of
the severe type, symptoms such as prostration, backache, pains, and vomiting are
experienced. This invasion period may last for two days. It may be entirely absent
from a mild case of smallpox. The number of cases under observation who have shown
no systemic disturbance prior to the development of the rash warrants the statement
that absence of prostration and systemic disturbance should not be permitted to
influence the diagnosis. In this connection it should be remembered that the "history"
given by patients and relatives is often incorrect and misleading.