An Outbreak of Psittacosis in Pigeons, Involving the Production of Inclusion Bodies, and Transfer of the Disease to Man

Abstract

An epizootic disease in pigeons associated with atypical pneumonia in two persons handling the birds has been studied. Most of the observations made during the work were consistent with the idea that we were dealing with an infection caused by a member of the psittacosis-lymphogranuloma venereum group of viruses. The outbreak was peculiar, however, in that tissues of the diseased pigeons contained many intranuclear inclusions and that the viruses isolated from these birds produced both intranuclear inclusions and elementary bodies in the cytoplasm of cells of chorio-allantoic membranes of the developing egg. Whether the pigeons were simultaneously infected with two viruses or whether the virus of pigeon psittacosis can produce intranuclear inclusions under certain conditions remains to be determined.

A New Virus Disease of Pigeons

“…In general birds infected with both psittacosis and I.N.I. viruses presented histopathological findings essentially identical with those previously encountered in pigeons in New York (1). Lesions observed in the two birds with uncomplicated psittacosis were similar to those described by others in pigeons (3,4) and parrots (5).…”

“…The procedures employed in the present study were, with the few exceptions mentioned in the text, those used in investigating the New York epizootic (1). The New York P-4 strain of psittacosis (1) served as the reference virus in the current work.…”

“…These newly isolated strains of virus, i.e., E.T., P-l-M, P-2-M, P-6-M, and P-8-M, were maintained by serial intracerebral passage in mice for seven to thirteen transfers while they were being identified. The strains maintained in mice were typical of psittacosis virus of pigeon origin (1,3,4). They were lethal for mice when injected intracerebrally in great dilution; thus after several passages they titered 10 -~ to 10-L Yet, even in high concentration they rarely killed mice when injected intraperitoneally.…”

Cell-wall Constituents of Rickettsiae and Psittacosis-Lymphogranuloma Organisms

“…Psittacosis (Ornithosis) P-4 pigeon strain isolated in 1942 from a sick pigeon in New York (Smadel, Wall & Gregg, 1943), material from a 42nd yolk-sac passage was used. Mouse pneumonitis (Nigg) Hampstead strain, isolated by Andrewes (see Andrewes & Horstmann, 1949) and passaged in mouse lungs.…”

Occurrence of Two Types of Intranuclear Inclusions in the Pancreas of Turkeys, of Which One Suggests a Virus Infection

“…Smadel, Wall and Gregg (1943) have described intranuclear inclusions in the acinar tissue of pigeons which they termed INI disease. In addition, there is a definite tissue pathology accompanying the cellular alterations which also would suggest that foreign agents of some sort were at work.…”