Epidemiological Situation on Tick-Borne Spotted Fever Group Rickettsioses in the Russian Federation in 2012–2021, Prognosis for 2022–2026

The aim of the review was to characterize the epidemiological situation on rickettsiosis of the tick-borne spotted fever (TSF) group in the constituent entities of the Russian Federation in 2012–2021 and provide a long-term forecast for 2022–2026. In 2020–2021, indicators of registered incidence of tick-borne rickettsiosis in Russia on the whole decreased relative to the average long-term pre-pandemic level in 2012–2019 by 2 fold for all forms of the TSF group on average (Siberian tick-borne typhus – STT, Astrakhan spotted fever and Mediterranean fever). A comparative analysis of the territories revealed a correlation between the incidence of STT and the number of medical facility visits due to “tick bites” (r=0.67, p=0.015), which, against the background of an increase in the frequency of contacts of the population with vectors in 2020–2021 in most regions and a decrease in the incidence in the same regions indicates the credible nature of the changes. The ranking of territories according to average long-term incidence rates made it possible to classify the Republic of Altai and the Altai Territory as regions of extremely high epidemic hazard as regards STT; high hazard – the Republic of Tuva; above average – the Republic of Khakassia, Khabarovsk Territory and the Jewish Autonomous Region. The established downward trend in the incidence of tick-borne rickettsiosis among the population will be sustained in most entities of the Russian Federation within the next 5 years, excluding the Republic of Altai, the Altai Territory, the Republic of Crimea and the city of Sevastopol, where current incidence or an increase should be expected. The results of the analysis indicate the need to put more emphasis on natural-focal infections at the time of COVID-19 pandemic

THE PRESENT STATE OF THE PROBLEM OF RICKETTSIOSES IN RUSSIA AND NEW APPROACHES TO THE CLASSIFICATION OF DISEASES CAUSED BY SPOTTED FEVER GROUP RICKETTSIAE

The paper presents analysis of the development and the current status of the doctrine about rickettsia and rickettsiosis. Progress in the study of Rickettsia is associated with, improved methods for their detection and isolation - using live biotechnological systems (cultivation in the experimental lines of ticks-sensitive lines of eukaryotic cells) in combination with methods of genotyping and. classical ricketsial methods. The development and. use of new methodological approaches to the study of tick-borne rickettsiae and other alpha-proteobacteria led to an important revision of ideas about genetic diversity, heterogeneity of antigenic and. biological characteristics, ecology and. contribution to the infectious pathology of various representatives of the order Rickettsiales in Russia

Clinical and laboratory characteristics of tick-borne rickettsiosis related to <i>Rickettsia sibirica</i> and <i>Candidatus Rickettsia tarasevichiae</i>

The Siberian tick-borne typhus (STT) is the most common tick-borne rickettsiosis (TBR) in Russia, registered in 17 administrative territories of the Southern Siberia and the Far East. The aim of this study was to describe clinical picture, pathological data and results of laboratory diagnostics during fatal mixed infection caused by two Rickettsia species most common in Russia — pathogenic Rickettsia sibirica and poorly examined Candidatus R. tarasevichiae, including identification of its etiological agents. A four-year-old girl in Krasnoyarsk Krai in a hyperendemic focus of the Siberian tick-borne typhus after tick sucking revealed typical TBR symptoms (scab at the site of tick suction, fever, spotted rash, myalgia) and meningeal syndrome, which is not typical for the Siberian tick-borne typhus. The child died on the seventh day of illness. Autopsy data (hepatosplenomegaly; cerebral edema, which was the immediate cause of death) and the results of histological examination (productive vasculitis of the brain, spinal cord and skin, polymorphic cell perivascular infiltrates in the liver and lungs, serous meningitis, myeloid hyperplasia of the spleen and lymph nodes, interstitial lymphoid infiltration in the myocardium) confirmed the clinical diagnosis of tick-borne rickettsiosis. The patient’s blood and brain samples were tested for a wide range of tick-borne pathogens and enteric viruses that cause brain damage using PCR followed by sequencing of the positive samples. The DNA of Rickettsia sibirica and Candidatus Rickettsia tarasevichiae was found in both blood and brain samples. R. sibirica was identified by the nucleotide sequences of gene fragments gltA, ompA and ompB, and Candidatus R. tarasevichiae — by the gltA and ompB genes using nested PCR and sequencing. All amplified fragments were sequenced in both directions; the obtained sequences were deposited in the GenBank database under the inventory numbers MK048467–MK048475. We have not identified other tick-borne pathogens or intestinal viruses in the patient samples able to result in meningeal syndrome. The area where the child was sucked by the tick belongs to the regions with a high incidence of STT. Several species of mites coexist in this area; of these, Haemaphisalis concinna, the carrier of R. sibirica, dominates the populations of Ixodes mites, while Ixodes persulcatus, the main reservoir of Candidatus R. tarasevichiae, is less common. As a result of the conducted studies, for the first time in the Russian Federation, a verified case of a lethal infection associated with two species of Rickettsia — Rickettsia sibirica and Candidatus R. tarasevichiae — was identified and described

Application of Molecular Typing Methods for Analysis of Strains of Rickettsiae of the Spotted Fever Group and Rabies Virus

50 strains of spotted fever group (SFG) rickettsiae and 36 lyssaviruses strains from the collection of Omsk Research Institute of Natural Focus Infections were identified and typed using the approaches of molecular biology, epidemiology and bioinformatics. The taxonomic status of the studied cultures of SFG rickettsiae was identified. Zonation of the Russian Federation territories according to the spread of SFG pathogenic rickettsiae in their hosts - ixodic ticks was carried out. Lyssaviruses distribution in the territory of Siberia was considered

Observation of Coherent Elastic Neutrino-Nucleus Scattering

The coherent elastic scattering of neutrinos off nuclei has eluded detection for four decades, even though its predicted cross-section is the largest by far of all low-energy neutrino couplings. This mode of interaction provides new opportunities to study neutrino properties, and leads to a miniaturization of detector size, with potential technological applications. We observe this process at a 6.7-sigma confidence level, using a low-background, 14.6-kg CsI[Na] scintillator exposed to the neutrino emissions from the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory. Characteristic signatures in energy and time, predicted by the Standard Model for this process, are observed in high signal-to-background conditions. Improved constraints on non-standard neutrino interactions with quarks are derived from this initial dataset