off the top floor of Building 5 in the manner reminiscent of Dr. Armstrong’s attempt to
isolate the basement rooms of the old Hygienic Laboratory in Washington, DC in 1929,
when he was investigating psittacosis. Drs. Olson and Larson also donned rubber boots,
gloves and facemasks. Before leaving the laboratory they took showers and put on
complete changes of clothing.
Drs Olson and Larson were able to isolate an agent that they hypothesized was a
virus. It has gone by the name of “The Agent of Louisiana Pneumonitis.” The organism
possessed resemblances to psittacosis and was thought to represent a new member of the
psittacosis-lymphogranuloma venereum group now designated as Chlamidia. The
pathologic changes in the organs found at autopsy were similar to those found in
psittacosis. The organism has not been known to recur since the original outbreak. Drs.
Olson and Larson apparently were able to make a vaccine that protected laboratory
animals from infection with the organism. If the organism reacts like other members of
the Chlamydia group, it should respond to treatment with current antibiotics.
There was speculation about the origin of the organism. The investigators noted that the
first recognized site of occurrence was near old ocean beaches stranded in the Louisiana
coastal marshes. The Chenieres are the winter home of varieties of northern birds and are
along the path of one of the great “fly ways” for migratory birds moving to and from the
two Americas. It was not unreasonable to speculate that an organism similar to psittacosis
could have been hosted by an unknown migratory bird group.
The decade 1940 to 1950 was a time of many organizational and administrative
changes at the National Institute of Health as the scientific campus expanded in Bethesda.