<< contents

PHYSICAL AND BIOLOGICAL SAFETY IN CENTERS WORKING WITH PATHOGENS

N.A. Staritsyn, E.A. Tjurin, N.P. Stegantsev, T.A. Djakova, L.I. Marinin, V.J. Volkov

State Research Center for Applied Microbiology

Research work with pathogenic microorganisms is connected with risk of emergency situations, laboratory infection of working personnel, and also with other consequences (Pike et al).

The cases of infection of humans in microbiological laboratories were registered during all the history of microbiology and are considered as convincing confirmation of professional danger or professional risk.

The urgency of a problem of protection of working stuff and environment during work with pathogens increased in conditions of wide introduction of achievements of microbiology, gene engineering, development of a microbiological industry, and also probable use of biological agents in the terrorist purposes.

Question of probable consequences of inadvertent or deliberate introduction of microorganisms into environment and, accordingly, readiness for liquidation of consequences of such events is always important.

The readiness for unpredictible situations is connected to reception of new knowledge about origin of pathogens, infection and development on this basis of new means of diagnostics, preventive maintenance and treatment, which will serve for the minimization of negative consequences. There are exist specialized facilities for realization of such investigations, in which due to complex measures the safe operations are provided. For example, in USA exist more than 40 laboratories of a level BSL-3, 4.

Research work with pathogens is always conducted in special conditions of a safe biological mode, however risk still possible. The risk of infection for working staff is connected with many technical details and depends on series of reasons. First it is the species of microorganism and its danger to the person. In the majority of countries, including in Russia, microorganisms are divided depending on a degree of danger to 4 groups according to the recommendations of the World Health Organization.

The microorganisms of 1 and 2 groups of pathogenicity in Russian classification namely plague, natural smallpox, hemorrhagic fevers, anthrax, tularemia, melioidosis, encephalitis etc. are most dangerous.

Classification accepted in USA, Canada and Japan, differs from existing in Russia by the return order: the microorganisms of the highest degree of pathogenicity are referred to 4-th group.

The work with microorganisms, their account, storage and transportation are regulated by the Sanitary rules - SR 3.1.1381-03, which are directed on maintenance of personal and public safety at transportation, and also exception of the non-authorized transfer and non accountable storage.

With the purpose of a safety for staff and exception of release of dangerous pathogens into environment the principle of zones or categories of premises is used. According to Sanitary rules laboratories depending upon a degree of danger for staff are divided into three regions (zones): II - infectious region (zone) - the researches with microorganisms of 1-2 groups of pathogenicity are conducted; IIa - conditionally infectious free region (zone) - the researches are not conducted, the preparatory work is carried out; I - pure (clean) region (zone). Accordingly to the American classification depending on a risk level premises (room) divided into four categories.

BSL-4 - the premises in which carried out work with microorganisms of I group of pathogenicity-Russian II category.
BSL-3 - the premises where carried out work with II group of pathogenicity-Russian II category.
BSL-2 - the premises where carried out work with microorganisms of III-IV group of pathogenicity -Russian I category.
BSL-1 - the premises where carried out work with microorganisms of IV group of pathogenicity-Russian I category.

Separation to the categories is sustained by several measures, one of which is the maintenance of hermetic enclosuring building designs. With the purpose to check the hermetic sealing the specific tests are carried out once per 12 months and more often if necessary.

Microbiological, genetic, biochemical, immunological researches with microorganisms of 1-st and 2 groups of pathogenicity (plague, anthrax, tularemia, melioidosis), and also with microorganisms of 3-rd and 4-th groups of pathogenicity are conducted in SRCAM according to scientific, including International programs. The properties of wild virulent isolates with determination of virulence and also vaccine strains are studied.

Modern methods of researches of dangerous and partly dangerous pathogens also should be supplied with a complex measures of physical and biological safety, which would exclude risks of an output of microorganisms and infection of stuff. It is necessary to have in mind, that wide experience on sources of intralaboratory infection accumulated for the present moment, and low enough doses of many pathogens for humans once again confirm importance of integrated approach of measures of engineering and biological character (Pike et al).

There are three basic aspects of a problem of a biosafety: organizational and control questions, engineering decisions, medicobiological measures. All of them are interdependent. Only comprehensive systemic approach towards development and realization of necessary measures can ensure the effective decision of a problem as a whole.

Measures of organizational character include coordination of all works in range of safety, regulation and rules for work. It is necessary to relate: the control of serviceability and efficacy of works of systems of safety, control of specific infection rate of air, workrooms, material flows, constant visual and tool control of fulfillment by staff of requests of safety.

High saturation by engineering systems and equipment force to have significant on number, well theoretically and practically readied service staff. Therefore significant attention is given to professional training of staff.

For achievement of the basic aim that is the protection of environment and working staff separate engineering systems as well as their complexes exist. They work on principles:

Safety work with microorganisms is provided with set of measures:

One of directions is the medicobiological safety of work with pathogenic microorganism, which includes a complex of preventive, medical and antiepidemic measures.

The medical support of staff involved in work with dangerous pathogens includes a dispensary observation for the employees and daily medical survey before the beginning of work. The periodic survey of the employees is carried out by the doctors of the specialized medical stuff.

Important component of medicobiological safety is the daily medical survey, which is carried out before an entrance into laboratory premises by the medical worker.

The specific preventive medical measures is vaccination of personnel accordingly definite schedules. Important direction of activity is physical safety of facility, which is provided with multilevel system of the control of access.

Modern laboratory base with levels of protection BSL2 and BSL3 exist in SCRAM which corresponds to WHO regulations and requirements for work with dangerous pathogens. The engineering and medicobiological measures permit to ensure safety of the people and environment due to normal functioning and maintenance in an efficient state of engineering systems, realization of preventive repair work.

<< contents

Proceedings of First Russian Workshop on Biological Security
Copyright © Committee of Scientists for Global Security and Arms Control