View report page

73
When a person is attacked by one of the more common infectious
diseases, it can be assumed that he contracted the infection in his home or
at his work or his immediate surroundings in the recent weeks. In the
case of tuberculosis, however, this is not so; the patient may have been
developing the disease for many months, during which time he may
have moved from his place of residence or his place of work at which
he was when the disease first started to overcome his resistance. For this
reason, then, the notification rate might not be an index of the healthiness
of a community, particularly if for any reason there is much movement of
population. Another factor is present in the case of a community which
is growing by the influx of new population. The patient once notified
remains notified for a long time. In any population which moves into
a new district, then, there will be not only those who have been notified
within the last year, but all those notified over the previous years. All
these might, as they should, be notified to the new authority very shortly
after their transference into the new district. The number of notifications
received in the district, then, will be swollen by a much bigger figure when
a population moves into the district. These factors do not arise in
stable communities, but they are of much importance in developing
districts. If the notification rates are to be accepted as any guide to the
healthiness of the community, as they might well be, only those of persons
who are considered to have contracted the infection while living there
should be counted. In view of the usual slow rate of onset, some arbitrary
period such as six months from the date of first residence in the district
might be taken, it being assumed that a person in whom the disease was
first recognised within six months of his coming to live in any area must
have contracted the disease because of the conditions in which he was
living or working before he transferred.
Register.
The names of all patients notified or otherwise brought to notice
are entered on the register. While names are constantly being added,
some are being removed, and this for one of a number of reasons. The
patient might have left the district; he might have died. In some cases
a patient is later discovered to have been notified in error and the notification
is withdrawn. Some patients recover completely. Before
the name of such a patient can be removed, it is necessary that the disease
shall seem to have been arrested for a number of years, and the names are
not removed until the lapse of an appreciable time after the disease has
reached a quiescent stage, one in which the patient has apparently
recovered. Most of the names removed are of those who have moved
from the district. Most of these are learned of either from the physician
at the chest clinic that the patient attended or from the Medical Officer of
Health of the district to which the patients have removed. Information
is not received about all, and unless special enquiries are made, the
number accumulates each year of persons whose names are still on the
register of an area although the persons no longer reside there. These
inaccuracies result in there being an inflated figure of the number
on the register.