TRANSMISSION AND CULTIVATION EXPERIMENTS WITH HUMAN TRACHOMA AND THE EXPERIMENTAL DISEASE IN MONKEYS.

1. Conjunctival tissue derived from alien and native American white persons in New York City, having trachoma in an advanced stage, has been used successfully to induce in Macacus rhesus monkeys characteristic granular conjunctivitis. The transfer of infection was effected either by a single subconjunctival injection, or by repeated swabbing with conjunctival secretions. 2. Pathogenic strains of Bacterium granulosis have been recovered from the trachomatous tissues of six out of eleven patients. In addition, the organisms have been isolated from the monkeys infected with human material. 3. Repeated swabbing with secretions obtained from monkeys having experimental trachoma has given rise to characteristic granular conjunctivitis in normal animals. In addition, repeated instillations of suspensions of conjunctival tissue fragments derived from affected monkeys have led to characteristic infection of the conjunctivae of normal monkeys. 4. Contact infection occurs in monkeys, as it has long been known to occur in human beings; animals with smooth conjunctivae developing the experimental disease when merely caged with infected monkeys. 5. Repeated instillation of cultures followed by rubbing the eyelids will lead to the disease in monkeys, a method of transfer which indicates one manner in which the affection may be transmitted from man to man. Yet another manner of producing the experimental condition is by repeated swabbing with cultures of Bacterium granulosis. Noguchi has already reported the successful outcome of the subconjunctival inoculation of cultures and the spread of the disease from an infected conjunctiva to the other eye of the same animal. 6. Tissues derived from cases of human trachoma or from monkeys having the experimental disease induce, on conjunctival inoculation of Macacus rhesus monkeys, the same clinical and pathological effects as do cultures of Bacterium granulosis. The conjunctival lesions closely resemble, in clinical appearance and in microscopic changes, those of the follicular stages of trachoma in man.