Measles is one of the most contagious diseases, ranking in this respect
with small pox. It was apparently observed by the earliest medical
writers and has been known throughout the world for several hundred
years as a common epidemic disease. It is characteristic of measles
that it usually occurs in epidemics which vary much in severity, and
which appear especially in the spring months. At such times almost
every one in a community who has not had measles is affected. After
a longer or shorter interval when susceptible persons have again
accumulated, a new introduction results in another epidemic. In
cities a few cases occur every year and about every two or three
years epidemic outbreaks appear. Almost every person is susceptible
to measles until he contracts the disease after which there is almost
perfect immunity for life. Second attacks are very rare. As high as
98 or 99 per cent of people are originally susceptible. The disease
is usually contracted at the first exposure. If persons have escaped
in earlier life they may be affected in adult years, even at advanced
age. Among people who have never had measles, epidemics may take on
alarming proportions. When this disease was introduced into the Faroe
Islands in 1846, over 6,000 of the 7,782 inhabitants were attacked.
In 1775 measles was introduced into the Sandwich Islands and in four
months 40,000 of the population of 150,000 died. In 1875, measles
was carried to the Fiji Islands with the resulting death of one-fifth
of the population (20,000). In the late war many young men from rural
districts, who had never had measles, were brought together in military
camps. When measles gained entrance extensive epidemics resulted.
Because of the great contagiousness of measles, and its almost
universal susceptibility most persons are attacked early in life. While
it is especially a disease of childhood, it rarely occurs in infants
below six months of age. By the time 15 years has been reached about 90
per cent of children have had the disease.
Healthy children living in good hygienic surroundings usually pass
through measles without much trouble. Delicate, poorly nourished
children who live in institutions and in parts of cities where there is
overcrowding in unhygienic conditions often do badly and many of them
die. This is especially true of young children. As a cause of death
among children measles ranks third among the acute contagious diseases.
In the registration area of the United States in 1920, there were 7,712
deaths from measles of which 78 per cent were in children under 5 years
of age. In Chicago from 1917 to 1921, 718 deaths from measles occurred,
over 90 per cent of which were children under 5 years of age. In this
country 2 to 3 per cent of children in private families who have
measles die, but in institutions and hospitals the deaths may reach 6
to 10 per cent.
Emphasis has been placed on the fact that measles causes many deaths,
especially among young children, in order to draw attention to the
fact that young children, especially those not very strong, should be
kept away from this disease as long as possible. To willfully expose
young children to measles, as is sometimes done, is dangerous and open
to the severest criticism.