Human plague in the United States.
To the Editor:— The Aug 5, 1962 issue ofThe Journalcarried a cover picture of a painting by Arnold Bocklin entitled "Plague" and an article entitled "Human Plague in the United States" by Caten and Kartman. This article and the caption next to the cover picture carry misleading statements which I would like to call to your attention. Discussing the distribution of wild-rodent plague in the United States, Caten and Kartman state, "The reason why plague does not extend beyond the 100th meridian is poorly understood." While it is true that all human cases associated with wild rodents for which adequate data are available have been acquired west of the 100th meridian, and this corresponds quite well to the known distribution of wild-rodent plague, as shown by Caten and Kartman, very limited surveys of wild rodents and fleas for plague have been conducted east of the 100th meridian. 1 Many investigators believe that wild-rodent plague does not extend into the eastern states, largely on the basis of the distribution of human cases associated with wild rodents. On the other hand, plague-infected wild rodents or their ectoparasites have been identified from over 130 counties in the western
THE PREVENTION OF PLAGUE IN THE LIGHT OF NEWER KNOWLEDGE
Knowledgc of the nature of the majority of pestilences which scourged the world in bygone ages is, admittedly, vague. It is certain, however, that plague is a disease of grcat antiquity, for, occasionally, some of the oldest records contain descriptions of a disease, sufficiently explicit to remove all doubt of its being plague.' Interest in the nefarious history of this malady has never varied. Pandemics and epidemics have been recorded in detail. However, explanation of the causes of their origin and development, as distinguished from the conditions which have generally been observed to favor their continuance and spread, has always been within the realm of speculation. All that is definitely known is that they were generally associated with unusual seasons, which bring distress and misery : with war and famine and their attendant ills, and with political, social or economic conditions which engender laxity or neglect of ranitary administration and thus hinder or entirely prevent prompt handling of early cases. Plague has acquired its ascendancy, both in the past and present, because knowledge of the different modes by which it spreads has been incomplete and, more frequently, because of ignorance of the biological laws governing these modes. Some of the modes are known. Since others, however, are unknown, there is always a risk that preventive measures employed may only be partially successful in checking and controlling the disease. Plague, the hydra-headed monster, has stretched its tentacles from continent to continent for nearly 3,000 years. Today, in fact, it appears to be even more widespread than during the great epidemics which began in the eleventh century and which, in the fourteenth century, culminated in a pandemic whose destructiveness cannot be matched in historical record. The present pandemic began in 1894, in Hong Kong. Except in India and a few other Asiatic regions, it has not caused a mortality comparable to that of old, although the prevailing types are as severe as in the past and the expansion of the
Rodents, Rabbits and Tularemia in North America: Some Zoological and Epidemiological Considerations1
The term “rodents” is often used to include all small mammals, particularly those of an injurious nature, yet, properly speaking, the rodents, Order Rodentia, are a definite zoological group best characterized by the chisel-like incisor teeth, four in number, and the absence of canine teeth. The rabbits, which were previously classed as a suborder of the rodents, are now placed by most mam-malogists in a separate order, the Lagomorpha, which was proposed by Gidley (1912). The rabbits differ markedly from the true rodents in their parasites, diseases, and reactions to disease.
Tularemia is stated by most writers to be a rodent disease but practically all have failed to distinguish between true rodents and rabbits.
Simpson (1929) states, “Tularemia exists primarily as an infectious disease of wild rodents particularly rabbits.”
Green (1931) says, “Tularemia is known to be a disease of rabbits as well as many other rodents.”