The purpose of this surveillance (non-interventional) clinical study is to genotype the causative agents of rickettsioses in biological samples of patients from the regions of Russia. This is a solely observational study in the patients with diagnosed or suspected tick-borne rickettsioses, with no intervention to the routine treatment and diagnostic process. During the study the medical history, diseases progress and symptoms, as well as treatments are being registered in individual case report forms. The rests of the samples used for standard diagnostics (blood, plasma, buffy coat, or serum, and/or swab of the eschar) are being collected and afterwards analyzed for rickettsial genotypes. These data are being compared to the medical history and symptoms of the patients in order to identify clinical patterns specific for causative agents of rickettsioses. Informed consent from all patients or their legal representatives are being collecting. The study was approved by the ethical committee.

This is an observational study with no intervention by the Sponsor or CRO in routine treatment or diagnostic process. Patient treatment strategy is not influenced by the study protocol or by the physician's intention to include the patient in the study; instead, is based on current standards of medical care for patients with rickettsioses.

The researcher (practicing physician) are being required to obtain written informed consent form (ICF) from each patient prior to inclusion. Biological sample collection are carried out using residual samples from standard diagnostics of patients who have signed an informed consent agreement. The researcher (practicing physician) start complete an individual case report form (CRF) for each patient who signed informed consent and whose biological samples have been collected.

Prior to the commencement of the study, the sponsor obtained approval from the ethics committee to conduct the study.

Inclusion Criteria:

To be included in the study, the subject must meet all the following criteria:

• Written informed consent by the subject (or their legal representative) to participate in the study;
• Men and women of any age, including children, who:

have sought medical care (outpatient or inpatient) with suspected or diagnosed rickettsiosis; or have sought medical care (inpatient) with a history of tick bites and elevated body temperature (at least 37.2 °C lasting at least 48 hours).

Exclusion Criteria:

- Inability or unwillingness of the subject (or their legal representative) to participate in the study

Male and female patients of any age with diagnosed or suspected tick-born rickettsioses.