Investigations implicated the Lone Star tick (Amblyomma americanum) as vector, and an aggregate of signs consistent with Bullis fever was reproducible in volunteers and guinea pigs inoculated with emulsified tick extract.
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.
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.
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.
In 1949, however, a case report of Bullis fever was published by physicians at Walter Reed Army Hospital in Washington, DC.
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,