THE MORBIDITY AND MORTALITY OF PERTUSSIS AND MEASLES WITH PARTICULAR REFERENCE TO AGE

ADDRESS BY THE CHAIRMAN

BORDEN S. VEEDER, M. D., St. Louis

Before taking up each disease separately it is of interest to note the position occupied by measles and pertussis in relation to the chief causes of mortality in infancy and childhood. In Chart I the percentage of deaths from different causes (74 per cent of the total) to the total number of deaths in children under two years (infancy) and in children under ten years is graphically shown. With the exception of accidents, birth injuries and congenital malformations, these represent the chief causes of deaths at this period of life. The great preponderance of deaths due to diarrhea and enteritis, premature birth and congenital debility (marasmus, atrophy, etc.) result in 65.7 per cent of all of the deaths under ten years occurring in the first year of life and about 80 per cent in the first two years. The percentage distribution of deaths in the first ten years of life is shown in the small insert in Chart I.

In Chart II the curve of each disease is plotted by year periods up to five years, and for the 5-9 year period. This chart shows the relative position of the different diseases as a cause of death at each age period. As there is such a preponderance of deaths in the first year of life the absolute number of deaths from a given cause may be very much larger in the first than in any succeeding year, but its relative position may be lower.

Although it will be seen that measles and pertussis together form but 5 per cent of the total mortality under ten years and 4.3 per cent of the mortality of infancy, Chart III shows why these diseases may be regarded as suitable for discussion by this society. In Chart III the age distribution of the deaths from these diseases is shown. Over onehalf (55.2 per cent) of the deaths from pertussis occur in infants under one year and over three-quarters (78.5 per cent) under two years. The mortality of measles is not so largely confined to infancy but nearly one-quarter (23.8 per cent) occurs in the first year of life and, as the result of the high death rate (31.5 per cent) for measles in the second year, over half of the deaths (55.3 per cent) in infants under two. These two diseases are in marked contrast to the two other contagious diseases of childhood which have an appreciable mortality and hence similar charts for diphtheria and scarlet fever are given for purposes of comparison.

Morbidity of Pertussis

Morbidity reports and statistics are very unsatisfactory. In many states and communities notification is of recent date and not compulsory for many diseases, and even when supposedly compulsory is very imperfectly carried out. This is due to a number of causes among which may be mentioned the lack of interest of some physicians who do not appreciate its importance, lack of power to enforce notification, questionable diagnosis, and the fact that many cases are never seen by physicians unless the child becomes extremely ill. At the present time measles is a notifiable disease in 38 of our 52 states and territories, and pertussis in 36, but the percentage of unreported cases is unknown. Examination of the Public Health Service records shows a marked fluctuation above and below the mean fatality rate that cannot be accounted for by differences in the virulence of epidemics alone, but

1 1 Reprint No. 332, Public Health Reports, 1916-xxvi-881