[Study of sensitivity of laboratory animals to a causative agent of argentine hemorrhagic fever].

AIM: Study sensitivity of laboratory animals to a causative agent ofArgentine hemorrhagic fever. MATERIALS AND METHODS: Junin virus strain XJ P37 was obtained from the State Collection of Causative Agents of Viral Hemorrhagic Fevers of the Pathogenicity Group I of Scientific Research Center of the 33rd Central Scientific Research Test Institute (SRC of the 33rd CSRTI). Junin virus strain XJ P37 culture with biological activity of 5.2 1g PFU x ml was used in the experiments. Mice (2 - 4 and 7 - 14 days old), guinea pigs (250 - 300 g), 1.8 - 2.5 kg shinshilla breed rabbits, 2.0 - 3.0 kg javanese macaque monkeys were obtained from vivarium of the SRC of the 33rd CSRTI. Vero (B) and GMK-AH-1 (D) cell cultures were obtained from cell culture collection of the SRC of the 33rd CSRTI. Biological activity calculation of Junin virus was carried out by Kerber in I.P. Amsharin modification. RESULTS: Lethality in animals was from 12.5 to 50% after intranasal and intraperitoneal infection of guinea pigs, intramuscular, intraperitoneal and subcutaneous infection of rabbits, intracerebral and intranasal infection of mice at the doses from 0.4 to 1.0 x 10(5) PFU. Death of infected monkeys after intramuscular administration of the virus at 1.0 x 10(4) PFU dose was not observed. In 100% of surviving animals formation of virus-neutralizing antibodies was registered. CONCLUSION: Evaluation of sensitivity of laboratory animals to Junin virus has shown that intracerebrally infected mice may be used to maintain causative agent culture, infected guinea pigs - to prepare virus-containing cultures and modelling infection exacerbation in humans. Intramuscularly infected rabbits may be used to obtain hyper-immune sera.

[Bolivian hemorrhagic fever].

Analysis of data of the available literature on epidemiology of Bolivian hemorrhagic fever, manifestations of human disease, biological properties of the causative agent and development carried out abroad of means and methods of diagnostics, prophylaxis and therapy of this infection that presents a potential threat for the population and economy of the Russian Federation in case of introduction of the causative agent is presented.

[The application of external and internal control objects in case of using of polymerase chain reaction and reverse transcription of polymerase chain reaction].

The external and internal control samples are used in case of polymerase chain reaction application to ensure validity of results. The external control samples are used to establish operability of reagents included into diagnostic kit. The internal control samples make it possible to check not only all the stages of reaction but also the process of amplification in each individual test tube with reaction mixture.

[Optimization of conditions of quantitative evaluation of argentine hemorrhagic fever causative agent].

AIM: Optimization of conditions of quantitative evaluation of Argentine hemorrhagic fever causative agent. MATERIALS AND METHODS: Junin virus (XJ P37 strain) was obtained from National collection of viral hemorrhagic fever causative agents of the 1st pathogenicity group of the 33rd Central Research Testing Institute. Junin virus (XJ P37 strain) culture with biological activity of 5.2 lg PFUxm(-1) was used in the experiments. Vero B, 6619-1(D) and GMK-AH-1(D) were obtained from collection of cell culture of the Research Scientific Centre of the 33rd Central Research Testing Institute. Calculation of biological activity of Junin virus during titration in cell cultures was carried out by Kerber method with modification by I.P. Ashmarin. RESULTS: During incubation for 4 - 7 days after the infection of cell monolayer the determined biological activity was 4.4 - 6.4 lg PFUxml(-1); the size of the formed negative colonies--(1.5 +/- 0.5) mm. CONCLUSION: The conditions of quantitative evaluation of Argentine hemorrhagic fever were optimized by negative colonies method (using 5 - 7 day Vero B cell culture monolayer with staining of monolayer on day 5 of secondary incubation, recording of results at day 7 after the infection).

[Rift valley fever].

In the last quarter of century virus of Rift valley fever (RVF) sharply extended its distribution by moving from Africa to Asia and evolving from low- to high pathogenic for humans causing severe hemorrhagic disease, practically equaling in this respect with some members ofa group of extremely dangerous pathogens. Morbidity and epidemics of RVF are analyzed. Evolution of epidemic development of the infection is examined. Necessity of development of means and methods for diagnostics, prophylaxis and therapy of RVF is underlined.

[Argentine hemorrhagic fever].

Features of the Argentine hemorrhagic fever are described in the review. Epidemiology, etiology, clinical presentation and pathogenesis of the disease are examined. Special consideration is given to the features of the pathological agent of Argentine hemorrhagic fever--the Junin virus. Features of the disease diagnostics are indicated--virological and serological studies, immunochemical and molecular-biological methods of identification of the pathological agent and antibodies against it. Approaches to etiotropic therapy of this disease and vaccination are examined. Based on the foreign experience perspective guidance for the creation of the system of protection of the population of the Russian Federation against Argentine hemorrhagic fever are presented.

[Hantapulmonary syndrome].

Features of hantavirus pulmonary syndrome are considered in the review - zoonosis natural focal polyetiological viral infection, that is characterized by lung injury. Etiology of the disease, main characteristics of the agents, epidemiology, contagiousness, pathogenesis, clinical presentation of this pathology are examined. Laboratory diagnostics, therapy and prophylaxis ofhantavirus pulmonary syndrome are described.

[Stabilization of peroxidase conjugates used in enzyme immunoassay systems to detect Ebola and Marburg virus antigens].

The time course of changes in the activity of solutions of horseradish peroxidase conjugates with immunoglobulins against Ebola and Marburg fevers was studied in the presence of different components. The series of the conjugates of ELISA kits for the detection of Ebola and Marburg virus antigens, which were prepared on the basis of the designed stabilizing solution, preserved at less than 90% of its baseline activity during 10 months at a storage temperature of 2 to 8 degrees C.

[Chemotherapy for Bolivian hemorrhagic fever in experimentally infected guinea pigs].

The efficacy of the antiviral agents nucleoside analogues manufactured in Russia and foreign countries against Bolivian hemorrhagic fever in the treatment and rapid prevention regimens was studied in guinea pigs. In rapid prevention and treatment of guinea pigs, the intraperitoneal injection of 1/10 of the equivalent dose of vero-ribavirin for this animal species was ascertained to protect 70% of the animals infected with Machupo virus strain Carvallo in doses 8 and 10 LD50.

[Use of guinea pigs to evaluate the efficacy of a heterological immunoglobulin against Bolivian hemorrhagic fever].

The use of guinea pigs as a laboratory model was proven to be appropriate in investigating the protective properties of a heterological immunoglobulin against Bolivian hemorrhagic fever at the preclinical stage of the study. A highly pathogenic Machupo virus strain that caused guinea pigs' death with respect with an agent's dose was cultivated. Injection of 1.0 ml of the immunoglobulin provided a 100% protective effect for the guinea pigs infected with the highly pathogenic Machupo virus strain in a dose of 10 LD50.

[Use of guinea pigs for assessing the efficacy of vaccines against Lassa fever]. / Ispol'zovanie morskikh svinok dlia otsenki éffektivnosti vaktsin protiv likhoradki Lassa.

The use of guinea pigs as a laboratory model was proven to be appropriate in investigating the vaccines developed against Lassa fever at the preclinical study stage. An adapted variant of Lassa virus was cultivated, which caused death of guinea pigs with respect for an agent's dose. Finally, it was shown to be possible to investigate the immunogenic and protective properties of the inactivated antigen of Lassa virus in experiments with guinea pigs.