TABLE OF CONTENTS PAGE THE FACTORS IN EPIDEMICS. By Alexander C. Abbott, Sc. D.... THE ARCHITECTURE OF JAPAN. By Warren P. Laird, Sc.D.............. PREFACE Prefatory words are scarcely necessary for the lectures contained in the present volume. They follow the course adopted in all previous years. These lectures bring the best thought of some of the most distinguished teachers in the teaching staff of the University of Pennsylvania. It is a pleasure to lay them before the friends of the University. THE FACTORS IN EPIDEMICS BY ALEXANDER C. ABBOTT Pepper Professor of Hygiene and Bacteriology, and Director of the Laboratory of Hygiene Since the pandemic of Influenza of last year, I have been asked so frequently questions bearing on various phases of the outbreak that I thought we might profitably consider this afternoon, the subject of Epidemics and Pandemics in general, and discuss those particular features of such outbreaks as may give an idea of the important factors concerned in the spread, and in the prevention of disease. In the first place there are terms employed that it may be well to define before beginning our discussion. The term "pandemic" refers to a world-wide spread of any particular disease. The term "epidemic" refers to a spread of a disease, not necessarily beyond the confines of a country or even a circumscribed community-but still a spread that is numerically so much greater than is customary to the place under consideration as to call for action and unusual effort at suppression; while the term "endemic" refers to the continuous presence of diseases of a transmissible character, among the population of a place. Thus we speak of typhoid and malarial fevers as endemic in those localities that are rarely free from a few cases of them. If in such places there be an advent of conditions favorable to a quick, sharp multiplication of the number of cases of those fevers, we say the disease has become epidemic. Diseases that become pandemic are rare, exotic and are often disseminated in ways not at first glance evident. It is this that accounts for the delay in checking their spread. Among the many questions that have been asked since the Influenza Pandemic are some that relate specifically to that disease, and others having a more general bearing. |