The syndrome, coined "Bullis fever," was self-limiting, but convalescence was protracted.
Although highly speculated, the etiology of Bullis fever was never proven, and a definitive retrospective diagnosis is unlikely.
Bullis fever typically commenced with subjective chills and fever from 102[degrees]-105[degrees]F.
A constant finding among patients with Bullis fever was leukopenia with associated neutropenia occurring on or about the second or third day of symptoms.
Typically, patients with Bullis fever suffered a mild, self-limiting, febrile illness of 7-10 days duration.
(3) Another study, conducted by the Army's 8th Service Command Laboratory, described the induction of an illness resembling Bullis fever in animals inoculated with clinical specimens.
A third paper, an epidemiologic study published at about the same time, reiterated the likelihood of A americanum as the vector for Bullis fever. (5) Collectively, these studies suggested that Bullis fever represented a previously unknown rickettsial illness with the Lone Star tick as likely vector.
In 1944, for example, there were 47 patients admitted with Bullis fever to Brooke General Hospital, compared to more than 500 cases the preceding year.1 Interestingly, 13 of these patients were treated with penicillin without therapeutic benefit, further implicating a rickettsial etiology.
These researchers found that a syndrome resembling Bullis fever could be reproduced in humans by inoculation with either whole blood from natural cases or with emulsified A americanum ticks.
Subsequent to that case report, there was a dearth of references to Bullis fever in the literature until 1975, when Anigstein and Anigstein published a review of the subject and proposed the name Rickettsia texiana for the hitherto unnamed etiologic agent.
the association of generalized lymphadenopathy with Bullis fever and its absence in human ehrlichiosis,