Genetic sequencing of a 1944 Rocky Mountain spotted fever vaccine

• Published in: Scientific reports Vol. 13; no. 1; p. 4687
• Main Authors: Xiao, Yongli, Beare, Paul A., Best, Sonja M., Morens, David M., Bloom, Marshall E., Taubenberger, Jeffery K.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 22-03-2023; Nature Publishing Group; Nature Portfolio
• Subjects: 631/326; 631/337; Animals; Coxiella burnetii; Deoxyribonucleic acid; DNA; Genomes; Humanities and Social Sciences; Infectious diseases; multidisciplinary; Next-generation sequencing; Pathogens; Phenols; Q fever; Rickettsia rickettsii; Rickettsia rickettsii - genetics; Rocky Mountain spotted fever; Rocky Mountain Spotted Fever - microbiology; Rocky Mountain Spotted Fever - prevention & control; Science; Science (multidisciplinary); Tick-borne diseases; Ticks - microbiology; Vaccines
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-023-31894-0

Rocky Mountain spotted fever (RMSF) is a rapidly progressive and often fatal tick-borne disease caused by
Rickettsia rickettsii
. Its discovery and characterization by Howard Ricketts has been hailed as a remarkable historical example of detection and control of an emerging infectious disease, and subsequently led to the establishment of the Rocky Mountain Laboratories (RML). Here, we examined an unopened bottle of a vaccine, labeled as containing RMSF inactivated by phenol-formalin of infected ticks, developed prior to 1944 at RML by DNA analysis using Illumina high throughput sequencing technology. We found that it contains DNA from the Rocky Mountain wood tick (
Dermacentor andersoni
), the vector of RMSF, the complete genome of
Rickettsia rickettsii
, the pathogen of RMSF, as well as the complete genome of
Coxiella burnetii
, the pathogen of Q-fever. In addition to genomic reads of
Rickettsia rickettsii
and
Coxiella burnetii
, smaller percentages of the reads are from
Rickettsia rhipicephali
and
Arsenophonus nasoniae
, suggesting that the infected ticks used to prepare the vaccine carried more than one pathogen. Together, these findings suggest that this early vaccine was likely a bivalent vaccine for RMSF and Q-fever. This study is the among the first molecular level examinations of an historically important vaccine.