The Bismarck tribune. [volume] (Bismarck, N.D.) 1916-current, 1930-07-24
Influenza Mortality

The Public Health service has recently completed a
study of influenza mortality in six epidcmics. This study
is based on weekly death rates from respiratory diseases
recorded as influenza and pneumonia in about 95 cities
of the United States during the period 1s2o-l92s.
From January /, 1920, to the middle of 1929 six cpl
denies of more or less national extent have occurred in
the United state-l92o, 1922, 1923, 1926. spring of 1928,
and the winter of l928-2e. Judging by the rates in the IS
cities, which seem to be only slightly higher than rates
for the country as a whole, these six epidenics caused III
excess of the normal or expected seasonal mortality from
respiratory diseases recorded as influenza and pneumonia,
approximately 250, 900 deaths in the country as a whole
a total of nearly one-half as many deaths as occurred in
the United States during the great pandcmic of 1888.
About one-fifth of these deaths, or $4,000, occurred dur
ing the recent epidemic of the winter of 1928-29, and
t%wo-fifths, or 100000, occurred during the sharp epidemic
of the early months of 1920.
Although these six cpidemicS were more or less nation
wide in extent, the various sections of the United States
were by no means equally affected. In the instance Of
several of the smaller cpidemics there appeared to be
whole sections of the country that were not affected. On
the other hand, certain sections of the country exper-
fenced fairly sharp ~epidenics in years when the rates for
the country as a whole did not indicate any Influenza
pneumonia deaths in excess of the median weekly rates.
An example OF this is an epidemic in the west south CEN
trail cities which occurred in the carly months of 1925,
a year when the remainder of the country appeared to be
relatively free from influenza.
The point of origin and direction of progress of these
six epidemics varies a great deal. Nearly every one Of
them arose in a different section of the country. The
le20 epidemic arose in the cast north central section and
progressed very rapidly to all other sections of the coun-
try. The 1922 epidemic arose in the east, probably in the
Middle Atlantic section, and the 1923 epidemic arose in
the cast south central section. The 1926 and the 1928-29
epidemics arose on the west coast, and the little epidemic
Of the spring of 1923 probably arose in the mountain or
west south central section.
The rate Of progress across the country varies a great
deal in the different epidenics. Considering the e5
cities as a whole, however, there is more uniformity in
the length of the epidemic. In 1920 the central half of
the deaths occurred in a period Of about is days. In the
epidemics Of l928-2o. 1922, and 1928 the central half of the
deaths occurred in periods of 81, %, and % days, re-
specuvely. In the small epidemic of the spring Of 1928
the period was - days, and in the epidemic of 1923 the
period was 30 days. The 1923 epidemic seems to show
the least INSTRUMENTATION of any of these recent out
breaks. In the case Of all the other epidemics the exces:
rate rose and fell at about the same rate, but in 1923 the
rise to the peak was considerably slower than the fall OF
the curve to the normal level again.