Antibodies to Tick Salivary Antigens AV422 and Calreticulin in Patients With Spotted Fever Group Rickettsioses and Other Febrile Illnesses in Northern Tanzania.

ABSTRACT:

Background

Timely and accurate diagnosis of spotted fever rickettsioses (SFR) is difficult due to nonspecific symptoms and testing challenges. We evaluated serum antibodies to the tick salivary proteins AV422 and calreticulin as potential markers of recent tick exposure in febrile patients from northern Tanzania.

Methods

We recruited febrile patients at 2 hospitals in Moshi, Tanzania, from February 2012 through May 2014. Acute and convalescent sera from enrolled participants were tested against Rickettsia africae antigen using indirect immunofluorescence assays (IFAs). Participants with ≥4-fold rise in R africae IFA immunoglobulin G reciprocal titer between sera were classified as cases (n = 70), those with paired sera with reciprocal titer ≥64 but no ≥4-fold rise as exposed

SUBMITTER: Moorthy GS 

PROVIDER: S-EPMC12530327 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature