A nested polymerase chain reaction (PCR) assay has been developed and used in the diagnosis of fatal and benign cases of Mediterranean spotted fever (MSF). The test was based on specific primers derived from a Rickettsia conorii 17-kD protein gene. A positive signal was obtained from spotted fever group (SFG) and typhus group (TG) rickettsiae. Discrimination between SFG and TG rickettsiae was based on a restriction fragment length polymorphism test. Other gram-negative bacterial species tested did not generate a signal, attesting for the specificity of the assay. The SFG-specific DNA fragment was detected in four of 29 acute-phase sera from serologically confirmed patients with MSF, while acute-phase sera from 25 patients without MSF were PCR negative. Acute-phase sera samples (five of five) and tissue autopsies (six of seven) from fatal suspected cases of MSF were PCR positive. The results demonstrate that sera and tissue samples are suitable specimens for the nested PCR tests, especially in fatal cases.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.4269/ajtmh.2002.67.166 | DOI Listing |
Pract Neurol
January 2025
Neurology Department, Hospital Clínico Universitario San Carlos, Madrid, Comunidad de Madrid, Spain.
Acta Trop
December 2024
Centro de Investigación en Alimentación y Desarrollo, A. C. (CIAD), 83304 Hermosillo, Sonora, Mexico. Electronic address:
Ticks are significant ectoparasites that transmit a variety of pathogens, leading to serious human and animal diseases, including Lyme disease, Rocky Mountain spotted fever, anaplasmosis and many others. The emergence of acaricide resistance in hard ticks presents a formidable challenge for public health and livestock management, exacerbated by the increasing incidence of tick-borne diseases and associated economic losses, estimated at $20 billion annually in the livestock sector alone. This review examines the mechanisms underlying acaricide resistance, focusing on genetic mutations, metabolic detoxification processes, and behavioral adaptations in tick populations.
View Article and Find Full Text PDFPLoS Negl Trop Dis
January 2025
State Key Laboratory of Pathogen and Biosecurity, Academy of Military Medical Sciences, Beijing, P.R. China.
Background: Tick-borne infectious diseases caused by the spotted fever group Rickettsia (SFGR) have continuously emerging, with many previously unidentified SFGR species reported. The prevalence of SFGRs in northwestern China remains unclear. This study aimed to examine the prevalence of SFGRs and Anaplasma species by analyzing tick samples collected from the Ningxia region.
View Article and Find Full Text PDFFront Cell Infect Microbiol
December 2024
Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA, United States.
Ixodid ticks serve as hosts and transmission vectors for several obligate intracellular bacteria, including members of the spotted fever group (SFG) of . Although ticks generate an immune response to bacterial insults, many of the signaling molecules associated with the response and how they may contribute to vector competence for are undefined. In this study, we isolated a full-length transcript from , which encoded a Relish-type NF-κB.
View Article and Find Full Text PDFExp Appl Acarol
December 2024
Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, SP, Brazil.
The tick fauna of El Salvador is currently represented by 10 species of hard ticks (family Ixodidae) and 2 species of soft ticks (family Argasidae). This study aimed to report new and additional records of ticks and rickettsiae in El Salvador. During 2019-2021, a total of 216 specimens of ticks were collected from eight host species (domestic and wild animals) and in the environment among 15 geographic localities of El Salvador.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!