Reactions of Monkeys to Experimentally Induced Streptococcus Hemolyticus, Group C, Infection

Abstract

Attempts to utilize animals for the experimental study of hemolytic streptococcus infections v/a the natural upper respiratory route, have rarely been successful. In 1913 Wollstein and Meltzer (1) induced a lobular pneumonia in dogs following intrabronchial insufflation of 15 to 20 cc. of a streptococcus culture. Graham and Bell (2) described similar findings following intratracheal insuffiation of 2 to 5 cc. of fluid obtained from a streptococcus empyema. Introducing intratmcheally, by means of a catheter, quantities of culture varying from 0.01 to 10 cc., Gay and Rhodes (3) induced bronchopneumonia in rabbits. Stillman and Branch (4) found the mouse susceptible to intranasal inoculation with the streptococcus. Subsequent investigators have confirmed the finding that the mouse is a suitable experimental animal for this bacterium.Blake and Cecil (5) produced pneumonia following intratracheal inoculations of a hemolytic streptococcus in Macaca syrichta but no respiratory infection occurred in a monkey receiving the inoculation via the nose and throat. The experiments described here were undertaken to observe the reaction of monkeys to intranasal instillation of Streptococcus hemolyticus, group C, under differing nutritional conditions. These studies were preliminary to investigations of the combined effects of influenza virus and streptococcus infections. Materials and Methods InfectiousAgent.--Streptococcu¢ hemolyticus, group C, isolated in 1936 at University Hospital from a case of scarlet fever, was maintained by storage al~ --78°C. The inoculum was prepared as follows: Virulent streptococci, as determined by mouse inoculations, were seeded on North's chocolate gelatin agar slants and incubated at 37°C. for 18 to 24 hours. The growth on the slants was gently washed off with sterile saline and the suspension adjusted to the desired turbidity. The larger particles were allowed to settle and the supematant was

Experimental production of respiratory tract disease in cebus monkeys after intratracheal or intranasal infection with influenza A/Victoria/3/75 or influenza A/New Jersey/76 virus

“…The severity of illness and magnitude of the antibody response are dependent upon the infecting strain of influenza virus, the dose of the inoculum, the route of inoculation, and the species of primate employed. Environmental alteration (i.e., nutritional deprivation and exposure to cold) has also been shown to influence the course of illness (16).…”