Michael A. W. Hattwick

Rocky Mountain spotted fever: epidemiology of an increasing problem.

Reported cases of Rocky Mountain spotted fever in the United States have been increasing since 1960 and reached an all-time high of 754 cases in 1974. Detailed clinical and epidemiologic information was obtained on 1522 (55%) of the 2757 cases reported in the 5-year period 1970 through 1974. Fifty-one percent of cases were confirmed by one or more laboratory test. The increase has occurred predominantly in the southeastern part of the United States. A comparison of laboratory-confirmed and unconfirmed cases suggests that a variety of febrile exanthems may be confused with Rocky Mountain spotted fever. Neither a history of tick bite nor rash was universally present, and both were significantly less frequent in fatal cases. The overall death-to-case ratio during this period was 6.8%. Death-to-case ratios were significantly higher for nonwhites (13.9) than whites (5.8), for male patients (8.2) than female patients (4.5), and for person older than 30 (13.9) than persons younger than 30 (5.4).

A nationwide outbreak of Reye's syndrome: Its epidemiologic relationship to influenza B

Between December 15 and June 30, 1974, 379 cases of confirmed Reyes syndrome were reported to the Center for Disease Control. Of these, 316 occurred during February and March 1974. A simultaneous surveillance system for influenza B indicated that this clustering of cases of Reyes syndrome correlated both temporally and geographically with influenza B outbreaks. The incidence of Reyes syndrome was higher in rural than in urban centers. Epidemiologically, two groups of cases of Reyes syndrome emerge: those which occur in older children (median age 11 years), cluster in time and geographic region, and are associated with antecedent influenza B infection; and those which occur sporadically thoughout the year, are isolated in occurrence, occur in younger children (median age 6 years), and are associated with a wide variety of antecedent viral illnesses.

Dealing with possible rabies exposure.

When a patient has come in contact with a domestic or wild animal that may be rabid, the physician must decide whether postexposure rabies prophylaxis is warranted. Among the factors that must be weighed are the animal species involved, the epizootiology of rabies, and the circumstances surrounding the exposure.

Limiting the effects of influenza epidemics.

Fewer than a third of the persons who would be at highest risk of dying during an influenza epidemic are receiving influenza vaccine. The federal Advisory Committee on Immunization Practices recommends selective administration of the vaccine to persons over age 65, those with chronic disease of heart, lungs, or kidneys, and those with diabetes or other chronic metabolic disease.