ABSTRACT
In recent years, members of the Coronaviridae family have caused outbreaks of respiratory diseases (MERS, SARS, and COVID-19). At the same time, the potential of radiation-induced inactivation of this group of viruses have been little studied, although radiation technologies can be widely used both in the processing of personal protective equipment and in the sterilization of vaccines. In the present work, the effect of 10 MeV electron beams and 7.6 MeV bremsstrahlung on the coronavirus infection pathogen (transmissible gastroenteritis virus) has been studied in vitro. In the given experimental conditions, irradiation with photons turned out to be more effective. The virus-containing suspension frozen at -86°C was the most resistant to radiation: the dose required for complete inactivation of the virus in this case was from 15 kGy, while for the liquid suspension and lyophilized form the sterilizing dose was from 10 kGy. At lower radiation doses for all samples during passaging in cell culture, residual infectious activity of the virus was observed. These differences in the efficiency of inactivation of liquid and frozen virus-containing samples indicate a significant contribution of the direct effect of radiation.
ABSTRACT
Purpose: The article covers issues related to providing personal protection equipment (PPE) for medical staff exposed to coronavirus (or similar infection) in the face of global pandemic and insufficient supply of infectious hospitals with disposable overalls. As many polymeric materials used to make such overalls do not feature required thermal stability and consequently they cannot be treated with heat disinfection, radiation treatment of protective overalls with electron accelerators for the purpose of their reuse was considered. Due to rich experience in addressing the issues of providing high-efficient, physiologically acceptable PPE for the personnel of radiation and chemical hazardous facilities, in particular during Chernobyl nuclear disaster elimination, the Laboratory of PPE for the Personnel of Hazardous Production Facilities, Burnasyan Federal Medical Biophysical Center, could extend methods of assessment and techniques of human protection against high-toxic substances to establishment of protection against microbiological threats. Results: The article provides results of analysis and tests of materials for overalls and respiratory PPE currently in use. Based on the material tests for radiation stability, air permeability, liquid penetration and protective properties with respect to aerosols, recommendations for improvement of efficiency and comfort of the PPE suite have been developed. Conclusion: The study showed feasibility of reusing overalls after radiation treatment. However, such treatment is appropriate only in periods of major emergencies during peacetime and wartime, when there are no production capabilities for manufacturing of new products. Location of the irradiation facility in the vicinity of consumers (e.g. medical institutions) is a prerequisite for this treatment. It should be emphasized that radiation treatment must be performed under strict supervision of accredited test facilities. Further research is required for development and enhancement of PPE and system of its application. This will allow to make longtime wear of PPE more comfortable without sacrificing its protective efficiency and develop a manual on product-specific radiation treatment. © 2020 State Research Center, Burnasyan Federal Medical Biophysical Center of Federal Medical Biological Agency. All rights reserved.